TW200414183A - Method of manufacturing original disk for optical disks, and method of manufacturing optical disk - Google Patents

Abstract

The present invention provides a method of producing an optical disk-use original and a method of producing an optical disk, capable of realizing the higher storage capacity of an optical disk by using an existing exposure system. The present invention is characterized in using an original formed with a specified uneven pattern that is formed by forming on a substrate a resist layer consisting of a resist material containing the imperfect oxide of a transition metal such as W and Mo, the imperfect oxide having an oxygen content smaller than that of a stoichiometric composition according to a valency capable of being possessed by the transition metal, and then by selectively exposing and developing the resist layer by a laser beam in conformity with a recording signal pattern, the uneven pattern then being transferred onto the optical disk.

Description

183. Description of the invention: [Technical field to which the invention belongs] and uses The present invention relates to a method for manufacturing a high-precision optical disc original disc. [Prior technology] First cited. The development of recorded media for all kinds of tribute is very significant, especially for small-sized recording media, while the recording method is being transferred from magnetic recording media to a mass of media, the increase in the recording capacity of s is recorded by MB (Mega shame (Megabit) level towards GB (GigaByte: Gigabit) level. In recent years, in the optical recording medium, the migration from compact discs (registered trademarks) toward light has also progressed, and 12-cm diameter read-only discs have a capacity of 4.7 GB on one side. This allows 2 hours of image recording in color standard mode (ntsc). However, with the rapid development of information communication and image processing technology in recent years, achieving several times the current recording capacity has become a problem in the above-mentioned optical discs. For example, the next generation of optical discs located on the extension line of digital video discs requires a single disc with a diameter of 12 cm to have a data capacity of 25 gb. This is the level at which digital high-day quality images can be recorded for about 2 hours. The above-mentioned optical disc has a fine uneven pattern such as a pit (Pit) or a groove (Groove) representing an information signal on one main surface of an optically transparent substrate such as polycarbonate, and aluminum is formed thereon. And a reflective film composed of a metal thin film, and further forming a protective film structure on the reflective film. In such a recording medium, the above-mentioned uneven pattern can be made finer.

O: \ 87 \ 87377.DOC -6- 200414183 to increase the recording density and thus increase the recording capacity. Here, FIG. 10 will be described below to explain the manufacturing process of the optical disc with the miniaturization of the concave-convex pattern of the optical disc. First, a photoresist layer 91 is uniformly formed on the substrate 90 (FIG. 10 (a)). Next, a selective exposure corresponding to the signal pattern is applied to the photoresist layer 91 to make it photosensitive (FIG. 10 (b)). By developing the photoresist layer 91, an original disc 92 (FIG. 10 (c )). Regarding the production of this master disk, the following is an example of the method performed previously. A glass substrate with a sufficiently smooth surface is used as a substrate, and the substrate is placed on a rotating base, so that the glass substrate is rotated at a specific rotation number, and a photosensitive photoresist (organic photoresist) is supplied onto the glass substrate. Coated. Next, the glass substrate is rotated to extend the photoresist, and the entire surface is spin-coated to form a photoresist layer. Secondly, by using the laser light for recording, the exposure photoresist has a specific pattern to form a latent image corresponding to the lean signal. Next, this is developed with a developing solution to remove the exposed or unexposed portions. Thereby, a photoresist master made of a specific uneven pattern formed by photoresist is obtained on a glass substrate. Next, a metal nickel film is deposited on the concave-convex pattern surface of the photoresist master disk 92 by the electroforming method (FIG. 10 (d)), and after the photoresist master disk 92 is peeled off, a specific process is applied to obtain the photoresist master disk 92. The stamping die 93 for molding to which the uneven pattern is transferred (FIG. 10 (e)). Using this molding die 93, a resin-made disc substrate 94 made of polycarbonate made of thermoplastic resin is molded by injection molding (Fig. 10 (f)). Next, the stamping die (Fig. 10 (g)) was obtained by forming a reflective film 95 (Fig. 10 (h)) and a protective film% of the A1 alloy film formed on the uneven surface of the resin-made disc substrate material.

O: \ 87 \ 87377.DOC 200414183 disc (Figure 10 (i)). In this way, the micro-embossed pattern of the optical disc is faithfully and instantly copied on the substrate by using a high-precision 'micro-embossed pattern stamping die': the process of Figure 1 was produced by the producer, and if traced further, it is based on the use of laser = Latent image is formed by exposure to the photoresist layer, that is, determined by cutting how to form a ^ fine uneven pattern. For example, in the previously described DVD-ROM with an information capacity of 4 7GB, the shortest pits with a length of 0.4 μηι and a track interval of 0.74 μπm are formed in a spiral shape on the stamping die to apply cutting. In this cutting, a laser with a wavelength of 413 mn is used, and the numerical aperture! ^ Is around 0.90 (for example, an objective lens. If the wavelength of the light source is set to; I (μιη), the numerical aperture of the objective lens is set to να , The shortest pit length P (μιη) that is exposed is represented by the following formula (丨). Furthermore: κ is a proportionality constant. Ρ = κ · λ / NA… (1) Here, the wavelength λ of the light source, and the length of the objective lens The numerical aperture NA is an item determined according to the style of the laser device that becomes the light source, and the proportionality constant rule is an item determined by the combination of the laser device and the photoresist master disk. In the case of making the aforementioned 4.7GB optical disc, Since the wavelength is 0.413 μm, the numerical aperture NA is 0.90, and the shortest pit length is 0.40 pm, according to the above formula (1), the proportionality constant K = 0.8 8. In contrast, in order to respond to the above 25 GB For the requirements of optical discs, the shortest pit length must be miniaturized to 0 · 17 μπι, and the interval between tracks must be miniaturized to a degree of 0.32.

O: \ 87 \ 87377.DOC 200414183 In general, the miniaturization of the uneven pattern (formation of extremely fine pits) described earlier is achieved by shortening the wavelength of the laser wavelength. That is, 'in order to obtain the shortest pit length of 1.7 μm required for a single-sided 25 GB high-density optical disc, a laser must be used in the case of a proportionality constant κ = 0.87 and a numerical aperture of 1 ^ 8 = 0095'. Light source with a wavelength of λ = 〇 · 丨 8 μιη. The wavelength required here is 0.18 μm, which is shorter than the wavelength of 193 nmiArF laser developed as a light source for next-generation semiconductor lithography. Realizing such a short-wavelength exposure device is not only a laser for a light source, but also optical components such as lenses require special ones, which are very expensive. In other words, the number of exposure wavelengths and short wavelengths and the numerical aperture NA of the objective lens have been increased to increase the optical resolution to correspond to the ultra-fine processing. With the progress of miniaturization, it is not possible to use the existing exposure device. Since an expensive exposure device is not introduced, it is extremely unsuitable to achieve the purpose of providing a low cost. Therefore, there is a limit to increase the memory capacity of the optical disc by increasing the function of the laser device in the exposure device. ~ 卞 / 久 八 7TG r and 3 camera photoresistance, and the exposure method of ultraviolet light as an exposure source is generally widely accepted. Organic pre-resistance is universal, and is widely used in the field of lithography. However, the exposed part and the unexposed part are clear due to the high volume, which corresponds to the earphone problem at the high level of 25GB. In contrast, the fine processing system of the Lixian disc has a fine pattern. In contrast, the small structure of the inorganic photoresist has a clear pattern at the boundary portion of the atomic level. In particular, the inorganic photoresist of the amorphous silicon can obtain exposure because of its largest size. And unexposed 'compared with organic photoresist, it can achieve high precision

O: \ 87 \ 87377.DOC 200414183 is considered to be suitable for high-capacity optical discs. This system is provided with MoO3 or W03 as photoresist materials, and ion beams as exposure sources. Gonghe J (Reference 1J Shikou: Nobuyoshi Koshida, Kazuyoshi

Yoshida, Shinichi Watanuki, Masanori Komuro and Nobufumi Atoda 'ff50-nm Metal Line Fabrication by Focused Ion Beam and Oxide Resists' ·, Jpn · J · Appl. Phys. Vol. 30 (1991)

ρρ3 246. ). In addition, there is a processing example using SiO 2 as a photoresist material and using an electron beam as an exposure source (refer to, for example, Sucheta M Gorwadkar,

Toshimi Wada? Satoshi Hiraichi, Hiroshi Hiroshima, Kenichi Ishii and Masanori Komuro · f, Si02 / c-Si Bilayer

Electron-Beam Resist Process for Nano-Fabrication (Si〇2 / c-Si double-layer electron beam photoresistance process), Jpn. J. Appl. Phys. Vol. 35 (1996) pp6673). Furthermore, the method of using selenium-selenium-tellurium glass as a photoresist material, using lasers with a wavelength of 476 nm and a wavelength of 532 nm, and ultraviolet light from a mercury-xenon lamp as an exposure source is also reviewed (refer to, for example, ······ Kostyukevych: " Investigations and modelling of physical processes in inorganic resists for the use in UV and laser lithography (SPIE Vol. 3424 (1998) pp20.). However, in the case of using an ion beam or an electron beam as an exposure source, various types of inorganic photoresist materials can be combined, and the concavo-convex pattern can be miniaturized by narrowing congregation electron beams or ion beams. Beam and ion beam irradiation source devices have complicated structures and are extremely expensive, so they are not suitable for the supply of O: \ 87 \ 87377 DOC -10- cheap discs. Regarding this point, you can use the existing heaters. The first to find, that is, the ultraviolet or keratin clothes are placed in the center. The ultraviolet or the machine first resists the material into the right furnace to become the first knife. The material of 彳 is limited. Materials. This is because of ultraviolet rays. Inorganic photoresist materials other than inorganic light-resistance materials are considered to pass through sulfur-coded tellurium materials. 'The absorption of energy is significantly less, and the existing exposure device and sulfur-selenium hoof are not practical. The combination of trembling is practical in economic terms. The sulfur field hoof material has

Ag2Se-GeSe, etc. on gAs2S3,. "The problem of harmful materials is difficult to use from the point of view of work." As mentioned above, 所述 ΓΓ has not yet achieved the high record valley 3 with the existing exposure device. : Manufacture of optical discs. Ben ': The author proposed to solve this kind of previous problems, and its purpose was to propose the safety of micromachining with high precision without using expensive irradiation equipment such as electron beam or ion beam. Resist material, using the existing exposure device, can realize 弁; 隹 _ _ _ _ _ _ _ _ _ _ _ _ _ is now a nine-disc further high memory capacity of the original disc manufacturing method and optical disc manufacturing method. [Summary of the Invention] As mentioned above, previously, a complete reduction of a transition metal such as 0.30 or 0.33 has been used as a photoresist material for electron beam or ion beam, and for UV or visible light, etc. Because it is transparent and its absorption is obviously small, it is difficult to perform microfabrication using ultraviolet or visible light as an exposure source. In contrast, as a result of a review by the inventors, it was found that as long as the oxygen content

O: \ 87 \ 87377.DOC -11-200414183 Slightly deviates from the stoichiometric composition of the transition metal oxide. This oxide's absorption of ultraviolet or visible light will suddenly increase. At the same time, by absorbing ultraviolet or visible light, its chemical The change in property f can be applied to the manufacturing methods of photoresist materials and optical masters. Also 'by this, the improvement of the proportional constant κ of the above formula (i)' can reduce the shortest pit length ρ. The manufacturing method of the original disc for optical discs of the present invention is designed based on the above considerations, and is characterized in that a film containing transition metal incomplete: oxide is formed on the substrate, and the oxygen content of the incomplete oxide is contained A photoresist layer composed of a photoresist material having a smaller oxygen content than the stoichiometric composition of the transition metal according to the aforementioned transition metal can be used to selectively expose and develop the photoresist layer corresponding to the signal pattern for recording to form a specific photoresist layer. Bump pattern. In addition, the manufacturing method of the optical disc according to the present invention is characterized in that a non-single lice compound containing a transition metal is formed on a substrate, and the oxygen content ratio of the incomplete oxide is in accordance with the transition described above. After the photoresist layer composed of a photoresist material with a small stoichiometric composition of metal and oxygen content is used, the photoresist layer is used to selectively expose and develop the signal pattern corresponding to the recorded signal pattern in § to form the original disc with a specific uneven pattern. , Making a disc transferred with the uneven pattern. The so-called incomplete oxide of a transition metal is defined herein as a compound that deviates in a direction that contains less oxygen than the stoichiometric composition of the recoverable valence of the transition metal, that is, the oxygen of the incomplete oxide of the transition metal. The content ratio is based on the compound of the transition metal described above. The number is reduced to f and the oxygen content is small. Furthermore, when there are multiple types of transition metals, there are crystal transition structures of U transition metal atoms—part of them may be replaced by other transition metal atoms.

O: \ 87 \ 87377.DOC -12- 200414183…, and the transition of these plural types with oxygen content ^ Doctrine 10 Jin Xiangshi θ and the metal can be mined, and is it enough? Judge whether it is an incomplete oxide. For the incomplete oxide system of the transition metal used in the material, external lines or visible light show absorption. Therefore, exposure can be performed without using an electron beam or ion beam to find a special exposure source. In addition, the transition = low-molecule, so compared to the organic light composed of high-molecular = can be ::: 2 :: The realm is clear, so by using this as a photoresist material, the photoresist pattern with 3 accuracy is returned. [Embodiment] The following describes in detail the "manufacturing of an optical disc according to the present invention" with reference to the drawings. Hereinafter, the outline of the manufacturing process of the optical disc to which the present invention is applied will be described with reference to FIG. First of all, on the substrate 100, a photoresist layer 1G2 composed of a first resistive material is uniformly formed by a low-intensity shot method. (The photoresist layer forms a guard order, and the figure shows the material suitable for the photoresist layer 1G2. In addition, in order to change the exposure sensitivity of the photoresist, a special intermediate layer 101 may be formed between the substrate 100 and the photoresist layer 102. Fig. 1 (a) shows the state. Furthermore, light The film thickness of the resist layer 10 can be arbitrarily set. However, it is better to be within the range of 10 to 80 g. Second, using an exposure device with an existing laser device, a signal is applied to the photoresistor 102. Selective exposure of the pattern to make it photosensitive (photoresist layer: photo process diagram 1 (b)). Furthermore, by developing the photoresist layer 102, a master 103 (photoresist layer development) forming a special uneven pattern is obtained. Process, figure ⑽) Next, metal is deposited on the uneven pattern surface of the original plate 103 by the electroforming method.

O: \ 87 \ 87377.DOC -13- 200414183 Nickel film (Figure 1 (d)). After peeling this from the original plate 103, a specific process is applied to obtain the stamping die for molding 1 transferred from the uneven pattern of the original plate 103 〇4 (Figure 1 (e)). Using this stamping die for molding, a resin-made disc substrate 105 made of polycarbonate made of a thermoplastic resin by injection molding was molded (Fig. 1 (f)). It is a person, peeling the stamping die (Fig. 1 (g), and forming a reflective film such as A1 alloy, etc. (Fig. 1 (h)) and a film thickness of about 0.1 mm due to the uneven surface of the resin-made disc substrate. The protective film 107 is used to obtain an optical disc (Fig. 1 (1)). In addition, the above steps until the optical disc is obtained from a photoresist original disc can be manufactured by a conventional technique. The photoresist material is suitable for the above photoresist layer 10.2. Photoresistive materials are incomplete liceates of transition metals. Here, incomplete oxides of transition metals are defined as compounds whose oxygen content deviates in a direction that is less than the stoichiometric composition of the transition metal based on its recoverable valence, That is, compounds containing oxygen in the incomplete oxides of transition metals that contain less oxygen than the oxygen content of the recoverable stoichiometric composition according to the valence of the transition metals described above. For example: Example: Chemical formula M03 as a transition metal oxide For explanation, if the oxidation state of the chemical formula MQ〇3 is converted to the composition ratio MQix〇x, it is a complete oxide with respect to the case of X-0.75, and the I * monthly condition expressed by 〇 < χ < 〇.75 is available. The oxygen content ratio is not the stoichiometric composition Incomplete oxides. In transition metals, there are 丨 elements that can form oxides with different valences. However, in this case, the scope of the present invention means that the actual oxygen contains the liberty in accordance with the transition. Insufficient stoichiometric composition of metal's recoverable value

O: \ 87 \ 87377 DOC -14- 200414183〉 Brother. / 列 士 口 · Λ / f _ • 10 is based on the trivalent oxide (Mo〇3) described previously as the most stable. He also exists monovalent oxide (Mo0). In this case, if t is replaced by the composition ratio M0ΐχ0χ, then within the range of 0 < x < 0.5, it can be said that the oxygen 3 has an incomplete oxide having a lower stoichiometric composition. Furthermore, the value of excessive metal lice can be analyzed by a commercially available analysis device. The incomplete oxide of this transition metal shows absorption of ultraviolet or visible light, and its chemical properties change due to being irradiated by ultraviolet or visible light. The details will be described later. However, as a result, although the photoresist is an inorganic photoresist, in the developing process, the etching speed of the exposed portion and the unexposed portion differs, and a so-called selection ^ is obtained. In addition, since the photoresist material composed of incomplete oxide of transition metal is smaller than the fine particles of the film material, the pattern of the boundary portion between the unexposed portion and the exposed portion is clear, and the resolution can be improved. However, due to the degree of oxidation of incomplete oxides of transition metals, their characteristics as photoresist materials also change. Therefore, the most appropriate degree of oxidation should be appropriately selected: For example, the chemical content of oxygen content is significantly higher than that of complete oxides of transition metals. Incomplete oxides with a small amount of composition are those that require a large amount with the exposure process: the injecting power, or the development process requires a long time and other inconveniences. Because of & oxygen: the amount is slightly less than the stoichiometric composition of the complete oxide of the transition metal = complete oxide is preferred. Specific transition metals constituting the photoresist material can be exemplified.

-, Fe, Nb, CU, Ni, C0, M0, Ta, W, ZrTiR, LG, r, ru, a, etc. Among them, it is better to use Mo, W, Cr, Fe, Nb. Visible light can obtain the viewpoint of large chemical changes ,:

Mo and W are preferred. Specially

O: \ 87 \ 87377.DOC -15- 200414183 In addition, as an incomplete oxide of a transition metal, in addition to an incomplete oxide of a transition metal, a second transition metal is added, or even a plurality of types of transition metals are added. Those metals other than transition metals are included in the scope of the present invention, and those containing a plurality of metal elements are particularly preferred. In addition, in addition to the incomplete oxide of one transition metal, in the case of adding a second transition metal, or even adding three or more transition metals, a part of one transition metal atom with a crystalline structure may be transitioned by other The metal rhenium is replaced by an atom. However, whether the oxygen content is sufficient relative to the recoverable stoichiometric composition of these plural kinds of transition metals is sufficient to judge whether it is an incomplete oxide. For other elements other than the transition metal, at least one of A1, c, B, Si, and Ge can be used. By combining two or more kinds of transition metals or adding other elements than the transition metals, the crystal grains of the incomplete oxides of the transition metals become smaller, so the boundary between the exposed and non-exposed parts is better and clearer, achieving a large The purpose of improving the resolution can also improve the exposure sensitivity. In addition, the above-mentioned photoresist material can be produced by a sputtering method in an Ar + 02 atmosphere using a target material containing a specific transition metal. For example: Relative to the total flow of gas introduced into the reaction chamber '〇2 is 5 ~ 2 ()%, and the gas pressure is the gas pressure (1 ~ 10Pa) of the usual sputtering method. Manufacturing method of optical disc master Next, a detailed description will be given of a manufacturing method of the optical disc master which constitutes the fundamental method of manufacturing the optical disc. As one embodiment of the manufacturing method of the original disc for optical discs of the present invention, its O: \ 87 \ 87377.DOC -16- is composed of, for example, as described above; an incomplete 41 of the transition metal formed on the substrate Photoresist material 丨 ...

The process of taking the special resist layer; the process of exposing and photosensitizing the photoresist, especially the concave of the layer I & Figure ^ "_Photoresist layer 'is made into a specific thin." The following explains the detailed process of forming the photoresist layer in each step. A photoresist layer composed of an incomplete emulsion of a transition metal is formed on a substrate with a sufficiently smooth surface. The specific film formation method can be exemplified by using money. The single metal is formed by the method of film formation in the argon or oxygen atmosphere by coinjection method. 々 ^ In this situation, the transition metal can be controlled by changing the oxygen gas concentration in the vacuum atmosphere. Degree of oxidation of incomplete oxides. In the case of forming incomplete oxides of transition metals containing two or more types of transition metals by the low-level shot method, the substrate is often rotated on the sputtering target J of a different type, and A plurality of kinds of transition metals are mixed. The mixing ratio is controlled by changing the power of each sputtering input. In addition, the mechanical injection method in an oxygen atmosphere using a dry metal material as described above is used. Use pre-containment period A dry material composed of an incomplete oxide of a transition metal in an amount of oxygen is subjected to a low-temperature shot method in a general argon atmosphere, and a photoresist layer composed of an incomplete oxide of a transition metal can also be formed into a film. In addition to the radiation method, a photoresist layer composed of incomplete oxides of transition metals can also be easily formed by evaporation. The substrate can be made of plastic such as glass, polycarbonate, silicon, alumina titanium carbide, nickel, etc. The film thickness of the resist layer can be arbitrarily set, for example, it can be set within the range of O: \ 87 \ 87377.DOC -17- 200414183 of 10 ~ 8011111. The photoresist layer exposure process is followed by the film formation of the photoresist layer. The substrate (hereinafter referred to as the photoresist substrate 1) is arranged on the upper side with a photoresist film-forming surface and is mounted on the rotating table 11 of the exposure device shown in Fig. 2. This exposure device is provided with an exposure photoresist layer, for example: laser light is generated The light beam generating source 12 has a structure in which the laser light generated thereby is focused and irradiated on the photoresist layer of the photoresist substrate 1 through the collimator lens π, the beam splitter 14, and the objective lens 15. Also, this exposure device With reflected light from the photoresist substrate 1 ' The beam splitter 14 and the condenser objective lens 16 are connected to the divided light sensor 17. The divided light sensor 17 detects the reflected light from the photoresist substrate 1 and forms the light obtained from the detection result. The focus error signal is transmitted to the main focus actuator 19. The focus actuator 19 is a position controller for the height direction of the objective lens 15. A transfer mechanism (omitted diagram) is provided on the rotary table, which can be changed with good accuracy. The exposure position of the photoresist substrate 1. In this exposure device, the laser driving circuit 23 is based on the data signal 20, the reflected light amount signal 21, and the compliance error signal 22, while controlling the light beam generating source 12, and performing exposure or focusing. In addition, a spindle motor control system and a 24 are set on the center axis of the rotary table, and the optimal spindle rotation number is set according to the radial position of the optical system and the desired linear speed to control the spindle motor. First, in the exposure process of a photoresist layer composed of an organic photoresist, the light source itself, which is not exposed, & the photoresist layer is focused. This is because the exposure of the organic photoresist is continuous to the change in the chemical f, so even if the necessary degree of water coke is weak &

O: \ 87 \ 87377.DOC -18- 200414183

The composition of the photoresist layer will cause unnecessary exposure. Therefore, prepare an organic photoresist that has no sensitivity. A long light source, such as a red light source with a wavelength of 633 nm, is used to focus the light. In this way, the first exposure device for organic photoresist uses two different wavelengths of chirp and original light. Because of this, there is no need to set up an optical system with separable wavelengths, so the optical system becomes very complicated, or its The cost and power are lacking. ”4 In the previous exposure devices for organic photoresistors, the resolution of the focus error signal used for the height and position control of the objective lens was determined by the light source used for detection (for example, a wavelength of 633 nm). ) Is proportional to the wavelength, so the resolution obtained with a light source for exposure cannot be obtained, and there is a problem that high-precision and stable focusing cannot be performed. In contrast, the photoresist material of the present invention of inorganic materials is shown in the relationship between the irradiation power of the light source for exposure and the difference (contrast) between the engraved speed of the exposed and unexposed parts. The change in chemical properties is extremely steep, that is, the irradiation power of the irradiation threshold power P0 for the incomplete exposure start is not performed even for repeated irradiation. Therefore, with the irradiation power of less than p0, Focusing can be performed with the exposure light source itself. Therefore: The manufacturing method of the original disc for optical discs of the present invention does not require a wavelength-separated optical system 'so as to reduce the cost of the exposure device, and at the same time achieve high-precision focusing equivalent to the exposure wavelength, and achieve accurate micro-processing. In addition, the weak light of the threshold power P0 is not fully irradiated, and the 1-resistance material of the present invention of the inorganic photoresist will not be exposed. Therefore, it is not necessary to use the ordinary organic photoresist to block indoor lighting. UV light. As described above, after focusing with light under the irradiation threshold power P0, the rotary stage 丨 丨 is moved to a desired radial position. Here, fixed 2 mirrors, 15 etc.

O: \ 87 \ 87377 DOC -19- 200414183 The position of the optical system in the face direction changes the exposure position of the photoresistive substrate 1 by moving the rotation ⑼. However, without further description, the photoresistive substrate 1 can be fixedly mounted The rotating table 11 changes the position of the optical system. Further, 'the laser light is irradiated from the light beam generating source 12 while rotating, and the photoresist layer is exposed. This exposure is based on the rotation of the rotary table by the _ side, and the rotary table 11 is continuously moved a little distance toward the radial direction of the photoresist substrate i by the _ side to form a latent image with fine unevenness, that is, the case of a recording disc A spiral guide groove is formed. x, In the case of optical discs, the concave and convex pits and guide grooves for information and data are formed as latent images of fine unevenness. In addition, when manufacturing concentric circular disks such as magnetic hard disks, it is possible to respond to the rotation stage or optical system step by step instead of successively. Based on the above, according to the information, the irradiation pulse or continuous light corresponding to the desired power of the irradiation threshold power P0 of the pit or the guide groove is sequentially irradiated from the desired position of the photoresist substrate 1 to Photoresist layer for exposure. Examples of the irradiation pulse are shown in Figs. 4A and 4B, and examples of the continuous light are shown in Fig. 4C. '' The photoresist material composed of the incomplete oxide of the transition metal of the present invention, by irradiating the threshold power? 〇 Irradiation of ultraviolet rays or visible light above, the chemical conversion of raw beaker and wheat, the etching rate for alkali or acid is different in the exposed part and the unexposed part, and the selection ratio can also be obtained. σ This means that the lower the irradiation power, the shorter and narrower pits can be formed. However, the irradiation power is extremely low, and it is difficult to form a stable pattern because it is close to the irradiation threshold power. Therefore, it is necessary to appropriately set the optimum irradiation power for exposure.

O: \ 87 \ 87377.DOC -20- 200414183 Furthermore, the present inventors have actually confirmed that by combining the photoresist material of the present invention, a red semiconductor laser with a wavelength of 660 nm, And exposure of a mercury lamp with a peak of about 405 nm, a selection ratio can be obtained to form a fine pit pattern. Photoresist layer development process is followed by 'developing the photoresist substrate 1 exposed in such a pattern to obtain a photoresist master for optical discs, which is formed by forming fine depressions or depressions according to a specific exposure pattern . Song shirt treatment can be obtained through the wet process of acid or test liquid, and the selection ratio can be appropriately used according to the purpose, application, equipment and so on. For the alkaline developer used in the dry process, an inorganic alkali aqueous solution such as a tetramethylammonium hydroxide solution, KOH, NaOH, and NaWO3 can be used, and as the acid developer, hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid can be used. In addition, the inventors have confirmed that, in addition to the wet process, even by a dry process called plasma or reactive ion etching (Reactlve Ion Etchlng: RIE), the type of gas and the mixing ratio of plural gases can be adjusted by Develop. Here, a method for adjusting the exposure sensitivity will be described. For example, when the oxide of a transition metal represented by the chemical formula w03 is converted into a composition ratio, a good exposure X sensitivity can be obtained in the range of "0" and "less than 0.75". At this time, a critical value of inconvenience such as a large irradiation power required for the mg exposure step, or a long time required for the development process, etc. _04 ~ 0.7 degree 'can obtain the highest exposure sensitivity. In addition, when the oxide of the transition metal represented by the chemical formula M03 is converted to the composition ratio M1 · Λ, it can be obtained in a range where x is larger than 0 · 1 and less than 0.75.

O: \ 87 \ 87377 DOC -21-200414183 Good exposure sensitivity. At this time, the threshold value of the inconvenience such as the large exposure and radiation power required for the exposure process or the long time required for the development process: and X is about G.4 to G.7, which can obtain the highest exposure sensitivity. Also, when the oxide of the transition metal represented by the chemical formula MoQ is converted into a composition ratio MO1-χ〇χ, a good exposure sensitivity can be obtained in a range where X is larger than 0.1 and less than 0.5. At this time , Χ = 〇1 is the critical value of inconvenience such as the large exposure and radiation power required for the exposure process to occur or the development process requires a long time. The higher the exposure range of the photoresist material, the more it can reduce the exposure power during exposure. It can shorten the exposure time corresponding to the pulse width or line speed, etc. k 2 However, on the other hand, the right sensitivity is too high, 'unnecessary exposure occurred during focus setting', or the inconvenience caused by the lighting environment of the process room is inconvenient, so it is appropriate according to the application. Select the optimal exposure sensitivity. In addition to increasing or decreasing the oxygen content, the adjustment of the exposure sensitivity of the photoresist material of the present invention is also effective by adding a second transition metal to an incomplete oxide of the transition metal. : By adding Mo to WhOx, the exposure sensitivity can be improved by about 30%. In addition to adjusting the sensitivity of the exposure, in addition to changing the composition of the photoresist material, the substrate can be selected by selecting a substrate material or applying a pre-exposure treatment to the substrate.实际上. In fact, when using quartz, silicon, glass, and plastic (polycarbonate) as the substrate, investigate the difference in exposure sensitivity due to the type of substrate. 'Confirm that the sensitivity of the substrate is not the same as the exposure sensitivity.' Specifically, the order of sensitivity is Shi Xi, Quartz, Glass, and Plastic. This order corresponds to the order of thermal conductivity. As a result, the smaller the thermal conductivity, the better the exposure sensitivity. This is because the more the thermal conductivity The smaller the substrate, the more obvious the temperature rise during exposure, so as the temperature rises, the chemical properties of the photoresist material

O: \ 87 \ 87377.DOC -22- 200414183 due to significant changes. * Photopre-treatment includes a process of forming an intermediate layer between the substrate and the photoresist material, such as heat treatment, ultraviolet irradiation treatment, and the like. In particular, a substrate with a large thermal conductivity, such as single crystal silicon, is used. By forming the substrate on the substrate, the lower layer of v is used as the middle g, which can appropriately improve the exposure sensitivity. Because of the dry layer of the straw field, the accumulation of the photoresist material during the exposure is improved. Furthermore, W dioxin (SiOi emulsification tank N), oxidized aluminum (Al203), etc. are suitable as materials having low thermal conductivity for forming the intermediate layer. The middle layer of the T layer may be formed by a sputtering method or another evaporation method. In addition, after spin-coating a 5 μm UV-curable resin on a quartz substrate, the substrate was cured by irradiating ultraviolet rays to the liquid resin, and it was confirmed that the exposure sensitivity was improved compared to the untreated quartz substrate. This can also be explained by the low thermal conductivity of the UV-curable resin. In addition, the exposure sensitivity can be improved by pre-exposure treatment such as heat treatment and ultraviolet irradiation. Because by applying such pre-exposure treatments, although not completely, the chemical properties of the photoresist material of the present invention have changed to some extent. As mentioned above, the photoresist composed of incomplete oxides of transition metals with various characteristics can be made functional by the choice of material composition, development conditions, and substrates. From the viewpoint of expanding the application range of photoresist materials, Here, the 2-layer photoresist method is extremely effective. Hereinafter, the outline of the two-layer photoresist method will be described with reference to FIGS. 5α to 5. f First, before the first photoresist layer 30 composed of the incomplete oxide of the transition metal of the present invention is stacked, as shown in FIG. 5A, the first photoresist layer 30 is formed on the substrate.

O: \ 87 \ 87377.DOC -23- 414183 j Between the incomplete oxides of the transition metals of the barrier layer 30, a material with a very low selection ratio can be stacked as the second photoresist layer 32. -Its-under, '' As shown in FIG. 5B, exposure and development processes are applied to the first photoresist layer 30, and the first photoresist layer 30 is patterned. "Second, the pattern formed by the first photoresist layer 30 is used as a mask, and the second photoresist layer is subjected to a high selection ratio of _ conditions at the second layer 32 '. Thus, the first photoresist layer is transferred by' ㈣ 所 不 ' The pattern of 30 is on the second photoresist layer 32. At the end of the second use, the pattern of the photoresist layer 32 is ended by removing the first photoresist layer 30, as shown in FIG. In the case where the method is applicable to the present invention, for example, by using Γying as a substrate 'using a rhenium transition metal as the second photoresist layer, and performing RIE, plasma rheology, etc. using i-hole rhenium gas, the transition metal constituting the first transition metal can be incomplete The oxide layer has an infinitely large selection ratio. "Between the first resistive layers" is obtained as described above. In the method for manufacturing an original disc for an optical disc of the present invention, it is composed of incomplete oxides of transition metals previously described. It is a photoresist material, so it has the advantage of using inorganic photoresist, „can be combined with UV or visible 2 for exposure. This first look at the light at 4m is not inconsistent because for UV or may == can not use these as exposure Source, electron beam or ion beam, etc. Hexapods can be used separately, you can use the ultraviolet light with fast daylight speed or the previous helmet machine that can use the electron beam. Compared with the mining, history, etc., the optical disc can be made using the original f method. Significantly reduce the time required for exposure.

O: \ 87 \ 87377 DOC -24- 200414183 It also uses an inorganic photoresist material composed of an incomplete oxide of a transition metal. The pattern of the boundary between the exposed and unexposed parts is clear, and high precision U fine processing is realized. . In addition, during exposure, focusing can be performed with the exposure source itself, and the resolution can be obtained. In this way, 'when forming a fine pattern, the manufacturing method of the original disc for optical discs of the present invention is a method of reducing the proportionality constant κ in the relationship represented by P = κ · λ / ΝΑ' $ Same as the exposure wavelength With the short wavelength, the previous method of increasing the numerical aperture NA of the objective lens to achieve microfabrication can be further refined by using the existing exposure device. Specifically, according to the present invention, the proportionality constant κ can be less than 0.8, and the minimum fine processing cycle f of the workpiece can be made as shown below. f < 0.8 λ / NA According to the present invention, by using the existing exposure device as it is, it is possible to provide an original disc for an optical disc which is cheaper and more finely processed than before. 〃 Examples The following describes specific examples to which the present invention is applicable based on experimental results. Example 1 Example 2 Example 1 uses a trivalent incomplete oxide of W (tungsten) as a photoresist material 'to actually make a photoresist master for optical discs. First, on a sufficiently smooth glass substrate, a photoresist layer composed of incomplete oxide of W was uniformly formed by a sputtering method. At this time, a dry base material composed of w monomer is used to shoot in a mixed atmosphere of argon and oxygen to change the oxygen gas concentration to control the degree of oxidation of incomplete oxides. 2. Energy Dispersive X-ray spectrometer

O: \ 87 \ 87377 DOC -25- 200414183

SpeCtrometei :: EDX) Analyze the stacked photoresist layer, and express from time to time with the composition ratio u, X = 0.63. The thickness of the photoresist layer is 40%. The wavelength dependence of the refractive index was measured by a spectroscopic ellipsometry method. The photoresist substrate on which the film formation of the photoresist layer is finished is placed on a rotating stage in the exposure setup shown in FIG. 2. In addition, once the suspicious port is rotated by a desired number of rotations, the laser beam is irradiated on the side of the laser beam, and the actuator is used to set the position of the objective lens in the height direction so as to focus on the photoresist layer. Secondly, in the case of fixed optics #, such as the dry and the first, the hunting mechanism is set on the rotating table to move the rotating table to help + the desired position of the master in accordance with the information. The photoresist layer is exposed by irradiating the photoresist layer with pulses on the photoresist layer. This… In the state of rotating the rotary table, while the rotary table is continuously moved a little distance toward the half-control direction of the photoresist substrate, exposure is performed. The exposure wavelength was 4.05 nm, and the numerical aperture NA of the exposure optical system was 0.95. The linear velocity during exposure was 2.5 m / s, and the irradiation power was 60 reads. " Second, a wet process using a developer is used to block the substrate before the exposure of the developer is completed. This development process is to immerse the photoresist substrate in a developing solution. In order to improve the uniformity of the last name, development is performed in the state of applying ultrasonic waves. After the development is completed, #wash thoroughly with pure water and isopropyl alcohol. Clean, and end with: wind ㈧ΓΒ1-wait for it to dry. A tetramethylbismuth hydrogenated aqueous solution was used as the developing solution, and the developing time was 30 minutes. FIG. 6 shows a photoresist pattern after development was observed with a scanning electron microscope (Scaring Electron scope · SEM). In Fig. 6, the photoresist layer corresponding to the exposed portion 'and the unexposed portion of the pit portion becomes a concave portion. In this way, a photoresist material composed of an incomplete oxide of W becomes a so-called positive photoresist.

O: \ 87 \ 87377.DOC -26- 414183 4. In the photoresist layer composed of incomplete oxides that are exposed to w, the insect engraving speed of the unexposed part is slower than that of the exposed part, so the light of the unexposed part is light. The film thickness of the resist layer after development is also maintained substantially after development. On the other hand, the exposed portion and the photoresist layer are exposed to the exposed portion by removing the surface of the glass substrate. Furthermore, among the four pits shown in FIG. 6, the smallest pit is 0.15 in width and 0.16 in length. In this way, it can be seen that by using the manufacturing method of the original disc for optical discs using the photoresist material of the present invention, compared with the concave width expected by the previous organic photoresist, the width is 0.39 μΐΏ, which can significantly improve the resolution. It can also be seen from Fig. 6 that the edges of the pits are very clear. It is also known that the width and length of the pits after development are changed by the irradiation power and pulse width of the exposure light source. Comparative Example 1 Comparative Example 1 uses W complete oxide W03 as a photoresist as a silk master for optical discs. 1 First, a photoresist layer composed of a complete oxide of w is deposited on a glass substrate by a sputtering method. When the stacked photoresist layer is analyzed by EDX and expressed in composition ratio WkOx, x = 0.75. Furthermore, from the analysis results of electron beam diffraction using a transmission electron beam microscope, it was confirmed that the crystal state before the exposure of the incomplete oxide was amorphous silicon. Exposing this photoresist layer with an irradiation power equal to or sufficient intensity as in Example 1 could not achieve a selectivity greater than 1, and a desired pit pattern could not be formed. In summary, the complete oxide of W is optically transparent to the exposure source, so it has a small absorption and does not cause chemical changes in the photoresist material. Example 2 O: \ 87 \ 87377.DOC -27- 200414183 As in Example 2 ', the trivalent and -trivalent incomplete oxides are used as f-resistance materials, and are actually produced according to the manufacturing process of ® 1 Discs with photoresist masters' Final sub-production discs. Hereinafter, implementation contents will be described with reference to FIG. 1. First, a Shixi wafer is used as the substrate 100. On the substrate, an intermediate layer 101 composed of amorphous silicon with a uniform film thickness of 80 nm is sputtered. Secondly, the photoresist layer 102 composed of the incomplete oxide that is formed on top of the film-forming method is wrong (Fig. I (a)). At this time, a sputtering target composed of an incomplete oxide of w & M0 was used, and sputtering was performed in an argon atmosphere. At this time, in order to analyze the stacked photoresist layer

The ratio of Mo is 80:20, and the oxygen content is 60%. The thickness of the photoresist layer was 55 nm. Furthermore, from the analysis results of electron beam diffraction using a transmission electron beam microscope, it was confirmed that the crystalline state before the exposure of the WMOO incomplete oxide was amorphous. After the exposure of the photoresist layer, except for the exposure conditions, the rest were processed under the same conditions as in Example 1 to produce a photoresist master 103 for optical discs (Fig. 1 (b), (c)). The exposure conditions of Example 2 are shown below. • Exposure wavelength: 405 nm • Numerical aperture of exposure optical system N A: 0.9 5

• Modulation: 17PP • Pit length: 112 nm • Track interval: 320 nm • Linear speed during exposure: 4.92 m / s

• Exposure irradiation power: 6.0 mW • Writing method: The same simple writing method as phase change discs: O: \ 87 \ 87377.DOC Photoresistance = case-example. W and M. The photoresist material composed of incomplete oxide becomes positive type. In the figure, the pits correspond to the exposed parts, and the photoresist layer in the unexposed part becomes the concave part. In addition, the formed pit length (diameter) ㈣ ~ was confirmed to be the shortest pit length required to achieve a high-density disc of 25 GB on the early side, and even the photoresist pattern was observed at 300 nm intervals in the direction of the pit row. ^ The state where pits of the same shape are formed toward a certain interval of 320 nm, and it is confirmed that the pits can be formed stably. Secondly, a metal nickel film is deposited on the concave-convex pattern surface of the photoresist master by electroforming (Fig. 1 (d)). After peeling from the photoresist master, a specific process is applied to obtain a concave-convex pattern on the photoresist master The transferred stamping die 104 (Fig. 1 (e)). '' Using this stamping die for molding, a resin-made disc substrate 105 made of polycarbonate made of a thermoplastic resin by injection molding is formed (Fig. 1 (f)). Next, the stamping die (Fig. 1 (g)) is peeled off, and a reflective film 106 (Fig. 1 (h)) of A1 alloy and a protective film 1 having a thickness of ^ mm are formed by forming the A1 alloy reflective film due to the uneven surface of the resin-made disc substrate. 〇7 to obtain a disc with a diameter of 12 cm (Figure 1 (i)). In addition, the above steps until the optical disc is obtained from the photoresist master are manufactured by a conventionally known technique. Fig. 8 shows an example of the pit pattern on the surface of the optical disc observed by SEM. Here, pits having a length of 150 nm, linear pits having a width of 130 nm, and the like are formed in a state corresponding to the actual signal pattern, and are confirmed to be a disc with a recording capacity of 25 GB. Next, the above-mentioned optical disc was read under the following conditions, the RIMt number thereof was obtained as an eye diagram, and a ## sweat estimate was performed. The results are shown in Figs. 9A to 9C. O: \ 87 \ 87377.DOC -29- 200414183 • Obedient servo: Push-pull calculation positioning method • Modulation: 17PP 1 • Pit length · 1 12 nm • Road interval · 320 nm • Reading line speed · 4.92 m / s

• Reading irradiation power ... 0.4 mW For the eye diagram (Figure 9A), the eye diagram (Figure 9B) that has undergone the basic equalization process has a jitter value of 8.0% and the eye diagram that has undergone the limiting equalization process ( The jitter value of Fig. 9c) is 4.6%, which is an extremely low value. As a disc with a recording capacity of 25 GB2 ROM, a good result without practical problems is obtained. Furthermore, the photolithography technology from the formation of the photoresist layer to the development of the present invention can also be applied to DRAM (Dynamic Random Access Memory): flash memory, ⑽❿ ㈤ρΓ 〇__

Unit Central Processing Unit), ASIC (Application Specific IC) and other semiconductor components; magnetic components such as magnetic heads; liquid crystal, EL (EleCtro Luminescence: electroluminescence),

Panel (plasma display panel) and other display elements; optical recording media, light modulation elements and other optical elements and other components. According to the above-mentioned X, in the manufacturing method of the original disc for optical discs of the present invention, since the layer is composed of non-π oxide of a transition metal that absorbs ultraviolet or visible light, it can be used in the existing ultraviolet or The visible light is the light of the exposure device of the exposure source. According to the present invention, a transition metal with a smaller molecular size is used as a photoresist material, so a good edge pattern can be obtained in the development stage of the photoresist layer, and a high-precision map can be achieved.

O: \ 87 \ 87377 DOC -30- 200414183. Therefore, by using such a disc to shake the original disc and the method of producing clothes, the _ γ 糸 can be made by using the existing exposure device manufacturing method, and the capacity disc. Yixin has a memory capacity as high as 25GB. [Schematic description] Figures 1 (a) to 1 (i) show the process diagrams applicable to this disc. Light of the manufacturing method of the pre-disc of u Figure 2 is a schematic diagram showing an exposure device used in the manufacturing method of the original disc for the pre-disc to which the present invention is applied. Chen & Wanfa's Figure 3 shows the exposure of the light source used for exposure, the exposure power, and the difference in etching speed between the exposed and unexposed parts of the light source used for exposure. The relationship between the characteristic map. The figure shows a characteristic diagram of an example of an irradiation pattern in an exposure process. Fig. 4A and Fig. 1 show examples of irradiation pulses, and Fig. 4 shows examples of continuous light. ㈣ to Tuwan are schematic cross-sectional views of the important part of the 2-layer photoresist. FIG. 5A is a step of forming a photoresist layer and a second photoresist layer, and FIG. 5β is a first photoresist layer pattern step. FIG.% Is a second photoresist layer engraving step, and FIG. Π is a first photoresist layer removal. Procedure. Fig. 6 is a photograph of a photoresist layer composed of incomplete oxides of w (tungsten) after development, observed by SEM. Fig. 7 is a SEM observation of a photoresist layer composed of% incomplete oxide and ^^ after development. 8 is a SEM observation of a recording capacity of 25 gb manufactured in Example 2.

O: \ 87 \ 87377 DOC -31-200414183 Photo of the pit pattern on the surface of the disc. 9A to 9C are diagrams showing signal evaluation results of an optical disc with a recording capacity of 25 manufactured in Example 2. FIG. FIG. 10 (a) to FIG. 10 (i) are process diagrams showing a conventional optical disc. [Illustration of representative symbols of the drawings] 1 Photoresistive substrate 11 Rotary table 12 Beam generation source 13 Collimator lens 14 Beam splitter 15 Objective lens 16 Condensing objective lens 17 Split light sensor 18 Focus error signal 19 Focus actuator 20 Information Signal 21 Reflected light signal 22 Compliance error signal 23 Laser drive circuit 24 Spindle motor control system 30 First photoresist layer 31, 90, 100 Substrate 32 Second photoresist layer 91, 102 Photoresist layer O: \ 87 \ 87377 .DOC -32- 200414183 92, 103 Original discs 93, 104 Stamping dies 94, 105 Resin-made disc substrates 95, 106 Reflective films 96, 107 Protective films 101 Intermediate layer f Minimum fine processing cycle K Proportional constant NA NA Numerical aperture P Shortest pit length P0 Radiation threshold power λ (of the light source) Wavelength, exposure wavelength O: \ 87 \ 87377.DOC-33-

Claims (1)

Scope of patent application: A method for manufacturing a master disc for optical discs, which is characterized in that: a metal-containing incomplete oxide is contained on the substrate, and the incomplete oxide is included; The stoichiometry of the valence number and the formation of the photoresist layer made of a green material with a small milk content, after forming the photoresist layer, the far-resistance layer should be selected to have a satin pattern and a specific concave-convex pattern corresponding to the recording pattern. A 2. 3. 4. 5. For the manufacturing method of the original disc for optical discs in the scope of patent application item i, wherein the aforementioned photoresist material is an amorphous inorganic material with an oxide. For example, the manufacturing method of the original disc for optical discs in the scope of the patent application, the transition metals in beans are Tl, v, Cr, Mn, Fe, Nb, Cu, Ni, co, Mo, Ta, W, Zr, Ru, From w to Ag. For example, in the method for manufacturing an original disc for an optical disc in the scope of application for patent i, the transition metal is either one or both of Mo and W. For example, the manufacturing method of the original disc for optical discs according to item 1 of the patent application, wherein an element other than a transition metal is further added to the incomplete oxide of the transition metal. 6. The manufacturing method of the original disc for optical discs according to item 5 of the scope of patent application, wherein the elements other than the transition metal are at least one of A, B, Si, and Ge. 7. The manufacturing method of the original disc for the optical disc as described in item 1 of the patent application scope, wherein the exposure is performed by ultraviolet or visible light. 8. The manufacturing method of the original disc for the optical disc as described in the item 1 of the scope of patent application, wherein the above-mentioned I, external line or visible light has a wavelength of 150 nm to 410 nm. O: \ 87 \ 87377.DOC 200414183 9. 10. 11. 12. 13. Manufacturing method, in which at least one kind of nickel is grouped as in the scope of patent application! The original disc for optical discs is made of glass, plastic, silicon The titanium oxide is used to form the photoresist layer on the substrate. ;: The manufacturing method for the application of 9 items of the optical disc is described below. Between the substrate and the aforementioned photoresist layer, an intermediate layer having a lower thermal conductivity than the substrate is formed. For example, in the method for manufacturing a master disc for an optical disc in the tenth aspect of the patent application, the above intermediate layer is a thin film composed of at least one of amorphous dream, stone dioxide, nitride stone, and oxide inscription. The method for manufacturing an original disc for an optical disc in the item i of the patent application, wherein the above-mentioned photoresist layer is formed by a sputtering method or an evaporation method. A method for manufacturing an optical disc, characterized in that an incomplete oxide of a transition metal is contained on a substrate, and an oxygen content ratio of the incomplete oxide is based on a stoichiometric composition of the foregoing valence of the transition metal. After forming a photoresist layer composed of a photoresist material having a small oxygen content, the light is selectively exposed and developed with the signal pattern corresponding to the recording layer to develop a master with a specific uneven pattern. The master is used to make a transferred bump Graphic disc. ^ O: \ 87 \ 87377.DOC