Photoetching mask manufacturing method based on nanoparticle monolayer array
Technical Field
The invention belongs to the technical field of micro-nano structure photoetching processing, and particularly relates to a photoetching mask manufacturing method based on a nanoparticle monolayer array.
Background
The array nano-structure is widely applied in the manufacturing fields of functional devices such as data storage, photovoltaics, energy storage, piezoelectricity, sensing and the like, and the manufacturing method of the nano-array structure comprises laser processing, electron beam etching, focused ion beam etching, micro-contact imprinting technology, photoetching technology and the like, wherein the photoetching technology is most widely applied due to the advantages of high manufacturing efficiency, good stability, low process cost and the like. In the photoetching technology, a mask is used for projecting incident light on photoresist, a nano structure is formed on the photoresist after development, and the projection constraint of the mask on the incident light is difficult to manufacture a nano array structure with a three-dimensional morphology.
Scientists use the regulation and control effect of nano particles on a light field, propose a photoetching technology (ACS appl. Mater. Interfaces 2014,6,20837-20841, doi. Org/10.1021/am505221 g) with a dielectric nano particle monolayer array as a mask, and realize the direct manufacture of the complex three-dimensional nano structure of the photoresist layer. However, the method for manufacturing the nanoparticle mask is limited to forming a large-area single-layer array of single nanoparticles, and is difficult to manufacture a complex photoetching mask formed by combining multiple single-layer arrays of nanoparticles, so that the wide application of the single-layer array of nanoparticles in the manufacturing process of the nano device is limited. Therefore, development of a complex mask manufacturing method capable of simply and controllably realizing localized arrangement of various nanoparticle single-layer arrays is needed, and efficient manufacturing of a power-assisted three-dimensional nano array structure is needed.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a photoetching mask manufacturing method based on a nanoparticle monolayer array, which is used for locally manufacturing nanoparticle monolayer array combinations with different diameters through inkjet printing, breaks through the limitation that the nanoparticle array mask can only be manufactured into a single morphology structure, and forms a nanoparticle monolayer array manufacturing technology with simple process, high efficiency and controllability.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a method for preparing photoetching mask based on nano particle array includes utilizing ink jet to print controllable water drop array, aligning nano particle array with different diameter on surface of water drop array, forming nano particle single layer film on surface of water drop by nano particle dispersion liquid and water drop being not mutually dissolved, forming nano particle single layer array after heating and drying, transferring nano particle single layer array to flexible transparent substrate, forming photoetching mask based on nano particle single layer array by regulating nano particle colloid material and diameter of water drop surface ink jet printing at different position.
A method of fabricating a photolithographic mask based on a nanoparticle array, comprising the steps of:
1) Preparing dielectric nanoparticle colloid ink;
2) Cleaning a substrate, and performing hydrophobic treatment on the surface of the substrate;
3) Performing hydrophilic treatment in the array pattern area on the hydrophobic surface of the substrate;
4) Performing water drop printing in a hydrophilic array pattern area on the surface of the substrate by using an ink-jet printer by taking ultrapure water as printing ink;
5) Using the dielectric nanoparticle colloid ink prepared in the step 1) as printing ink, and performing ink jet printing on the surface of water drops to form a nanoparticle monolayer film on the surface of the water drops;
6) Heating a substrate, and forming a nanoparticle monolayer array after water drops and dispersion liquid in dielectric nanoparticle colloid ink are completely evaporated;
7) And transferring the nanoparticle monolayer array to the surface of the flexible film to form a photoetching mask based on the nanoparticle monolayer array.
The nano particles in the step 1) are made of silicon dioxide, polystyrene, polymethyl methacrylate and the like, the nano particles are in a spherical or spherical core-shell structure, the dispersion liquid of particle colloid is n-butanol, cyclohexane, n-hexane, benzene, toluene, n-heptane, isooctane and the like, the diameter of the nano particles is 300-1200 nm, and the mass fraction of the particles is 8-20%.
The substrate in the step 2) is made of glass, metal and plastic polymers with flat surfaces, and the contact angle theta 1 of the surface of the substrate subjected to hydrophobic treatment meets the requirement that theta 1 is more than or equal to 100 degrees;
The contact angle theta 2 of the surface of the array pattern area subjected to hydrophilic treatment in the step 3) meets the requirement that theta 2 is less than or equal to 60 degrees;
the area S of the water drops after being fully paved in the hydrophilic array graphic area unit in the step 4) of water drop printing is more than or equal to 5mm multiplied by 5mm;
the multi-nozzle of the ink-jet printer in the step 5) sprays dielectric nanoparticle colloid ink with different materials and diameters on the surfaces of water drops at different positions in the water drop array, and the ratio K of the total area of the nanoparticle monolayer film to the bottom area of the water drops is more than or equal to 0.8 and less than or equal to 1.2;
in the step 6), a hot plate is used for heating the substrate for 2-6 min, and the temperature of the hot plate is 50-90 ℃;
And in the step 7), a film with the thickness of 3-8 mm is formed as a uniform and stable transparent flexible substrate after Polydimethylsiloxane (PDMS) is coated on the surface of the nano particle monolayer array for curing, and the nano particle monolayer array is transferred into the PDMS film to form a photoetching mask.
Compared with the prior art, the invention has the beneficial effects that:
The conventional mask photoetching process can only obtain the quasi-three-dimensional structure of the re-etching mask, and is difficult to manufacture the three-dimensional structure with structural change in the vertical mask direction. The invention utilizes the ink jet printing technology to manufacture multi-size nano particle single-layer array locally, transfers the nano particle single-layer array to the flexible transparent substrate to form the photoetching mask, the nano particle single-layer array mask can regulate and control the energy distribution of a transmission light field, can directly manufacture a complex three-dimensional structure in a photoresist layer, is hopeful to form a resolvable photoetching structure capable of breaking through diffraction limit, and in addition, because the nano particle single-layer array structure photoetching mask is based on a flexible film, the nano particle single-layer array structure photoetching mask is easy to be tightly attached to the surface of the photoresist, particularly the surface of the photoresist of a micro-curved substrate, and the uniformity and the stability of the photoetching technology are improved.
Drawings
FIG. 1 is a schematic view of a smooth surface substrate according to the present invention.
FIG. 2 is a schematic representation of the surface hydrophobic treatment of a substrate according to the present invention.
FIG. 3 is a schematic illustration of a substrate with a patterned hydrophilic surface according to the present invention.
FIG. 4 is a schematic representation of an array of printed water droplets within a hydrophilic region of a substrate according to the present invention.
FIG. 5 is a schematic illustration of the alignment of the printed nanoparticle colloid on the surface of a water droplet according to the present invention.
FIG. 6 is a schematic diagram of a monolayer film array of different nanoparticles formed on the surface of a droplet of the present invention.
FIG. 7 is a schematic representation of a localized multi-sized nanoparticle monolayer array according to the present invention.
FIG. 8 is a schematic illustration of a flexible mask based on a monolayer array of nanoparticles according to the present invention.
Fig. 9 shows the electric field distribution on the surface of the EPG533 photoresist substrate after the incident 365nm uv light passes through the 400nm diameter polystyrene spherical particle array mask.
FIG. 10 is a diagram showing the structure of a photoresist layer on EPG533 after 365nm ultraviolet light passes through a 400nm diameter polystyrene spherical particle array mask.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
A method of fabricating a photolithographic mask based on a nanoparticle array, comprising the steps of:
1) Polystyrene spherical particles with the diameter of 400nm are selected to be dispersed in n-butyl alcohol in a mass fraction of 11%, so that uniform and stable nanoparticle colloid ink is formed;
2) Referring to FIG. 1, a glass slide with the thickness of 1mm is taken as a substrate 1, ultrasonic cleaning is sequentially carried out by adopting acetone, ethanol and deionized water, nitrogen is used for drying for 1h in a blast drying oven with the temperature of 150 ℃, and referring to FIG. 2, a C 4F8 film is deposited on the surface of the substrate 1 by using a plasma chemical deposition method to obtain a hydrophobic surface 2, wherein the contact angle theta 1 of the surface of the substrate subjected to the hydrophobic treatment is 128 degrees;
3) Referring to fig. 3, a mask is coated on a hydrophobic surface 2, and then a hydrophilic array pattern region 3 is manufactured on the hydrophobic surface 2 using an oxygen plasma cleaning machine, wherein a surface contact angle θ 2 of the hydrophilic array pattern region 3 is 50 °;
4) Referring to fig. 4, with ultrapure water as printing ink, water droplets are sequentially printed in the hydrophilic array pattern area 3 by using the head 4 of the inkjet printer to form a water droplet array 5, wherein the water droplets are spread with an area s=7mm×7mm in the hydrophilic array pattern area 3 unit;
5) Referring to fig. 5 and 6, the nanoparticle colloid ink prepared in step 1) is used as printing ink, nanoparticles 6 and 7 with different materials and diameters are respectively aligned and printed on the surface of a water drop array 5 to form a nanoparticle monolayer film 8 on the surface of the water drop, and the ratio k=1 of the total area of the nanoparticle monolayer film 8 to the bottom area of the water drop;
6) Referring to fig. 7, the substrate 1 is heated by a hot plate for 5 minutes at a temperature of 80 ℃ to obtain a plurality of different nanoparticle monolayer arrays 9 after the nanoparticle monolayer films 8 are heated;
7) Referring to fig. 8, a plurality of different nanoparticle monolayer arrays 9 were transferred to a Polydimethylsiloxane (PDMS) surface to obtain a nanoparticle array-based mask 10 having a thickness of 5mm.
For the FDTD simulation calculation of the transmission field of the polystyrene particle array in this embodiment, the electric field distribution is shown in FIG. 9, the maximum 10 times enhanced electric field hot zone can be formed in the photoresist layer at the bottom of the particle array, and the space three-dimensional array structure shown in FIG. 10 is obtained by developing the photoresist layer after exposure.
The foregoing is merely exemplary embodiments of the present application, and specific structures and features that are well known in the art are not described in detail herein. It should be noted that variations and modifications can be made by those skilled in the art without departing from the structure of the present application. These should also be construed as protecting the application, which does not affect the effect of the practice of the application and the utility of the patent. The protection scope of the present application is subject to the content of the claims, and the description of the specific embodiments and the like in the specification can be used for explaining the content of the claims.