WO2013137444A1 - Tape for continuity tests and continuity test method using said tape - Google Patents

Description

Continuity test tape and continuity test method using the tape

The present invention relates to a continuity test tape for conducting a continuity test in a state where a semiconductor wafer or a semiconductor chip is bonded.

Conventionally, a semiconductor wafer made of silicon, gallium, arsenic or the like is manufactured in a large diameter state, and then a semiconductor wafer continuity inspection is performed by an inspection process. Thereafter, the semiconductor wafer is affixed to a dicing sheet and subjected to a dicing process, a cleaning process, an expanding process, a pick-up process, and a mounting process. In addition, a continuity test of the semiconductor chip may be performed after the dicing process.

As a pressure-sensitive adhesive sheet for inspection used in the above inspection process, Patent Document 1 discloses a pressure-sensitive adhesive layer on a base film made of metal foil or a base film having a structure in which a conductive vapor deposition layer is provided on the base. A pressure-sensitive adhesive sheet in which is laminated is disclosed.

JP 2009-114394 A

According to the study by the present inventors, the pressure-sensitive adhesive sheet for inspection described in Patent Document 1 has no flexibility when the metal foil is used as the base film, and when bent, the original pressure-sensitive plastic deformation causes bending. There is a problem that the shape does not return. That is, the test adhesive sheet described in Patent Document 1 has poor handling properties. Further, the metal foil may damage the guide roll and the like, which may cause the apparatus to fail. Moreover, when using the base material which provided the electroconductive vapor deposition layer as a base film, it does not have electroconductivity in the lamination direction (thickness direction) of this adhesive sheet.

The present invention has been made in view of the above circumstances. That is, an object of the present invention is to provide a continuity test tape that is excellent in handling properties and that can easily perform a continuity test.

The present invention includes the following gist.
[1] A laminate comprising a base material provided with a plurality of through holes and a metal-coated base material made of a metal film, and a conductive pressure-sensitive adhesive layer.
Tape for continuity testing that has conductivity in the stacking direction.

[2] The tape for continuity testing according to [1], wherein a difference t1-t2 between the thickness t1 of the base material at the peripheral portion of the through hole and the thickness t2 of the base material other than the peripheral portion of the through hole is 60 μm or less.

[3] The continuity testing tape according to [1] or [2], wherein the through hole is formed by laser light.

[4] The continuity test tape according to any one of [1] to [3], wherein the metal film has a thickness of 60 to 1000 nm.

[5] The continuity testing tape according to any one of [1] to [4], wherein the total area of the through holes on one surface of the substrate is 1 to 10% with respect to the area of the substrate.

[6] The continuity testing tape according to any one of [1] to [5], wherein the conductive adhesive layer has removability.

[7] A continuity test method using the continuity test tape according to any one of [1] to [6].

According to the present invention, by providing a metal film on a base material provided with a through-hole and further providing a conductive pressure-sensitive adhesive layer, a continuity test excellent in continuity and handling properties in the thickness direction (stacking direction) and the surface direction. Tape can be obtained. According to the continuity test tape of the present invention, the continuity test can be easily performed.

The sectional view of the tape for continuity inspection concerning one embodiment of the present invention is shown. Sectional drawing of the tape for a continuity test which concerns on other embodiment of this invention is shown. Sectional drawing of the tape for a continuity test concerning another embodiment of the present invention is shown. The enlarged view of FIG. 1 is shown.

Hereinafter, the present invention will be described more specifically, including its best mode. As shown in FIGS. 1 to 3, a continuity test tape 10 according to the present invention includes a metal-coated substrate 6 composed of a substrate 1 and a metal film 2 provided with a plurality of through holes 4, and a conductive adhesive layer 3. And is conductive in the stacking direction.

[Metal-coated substrate]
The metal-coated substrate in the present invention comprises a substrate and a metal film provided with a plurality of through holes, and specifically, the surface of the substrate is coated with a metal film. Below, a base material and a metal film are demonstrated.

(Base material)
A plurality of through holes 4 are formed in the substrate 1.

The shape of the through hole is not particularly limited. The through hole in the present invention is formed by, for example, a method of piercing a thin needle into a substrate, a method of forming using a punch, or a method of forming using a spindle or laser light. Among these, a method of forming a through hole using a laser beam is preferable.

The laser beam that can be used in the present invention is not particularly limited, and examples thereof include a YAG laser and a carbon dioxide (CO ₂ ) laser. The repetition frequency of such laser light is preferably 5000 to 10,000 Hz. The pulse width is preferably 5 to 50 μsec. According to said laser beam, a desired through-hole can be formed, suppressing that a base material deform | transforms with the heat | fever generate | occur | produced with irradiation of a laser beam.

In the through hole formed by the above method, the diameter of the through hole on one surface of the substrate (surface 1a in FIGS. 1 to 3) is preferably 300 μm or less, more preferably 250 μm or less, and even more preferably 50 to 200 μm. It is.
When the diameter of the through-hole on one surface of the substrate exceeds 300 μm, when the conductive adhesive layer described later is formed on the substrate, the conductive adhesive layer may ooze out on the opposite surface, It may be difficult to form a smooth conductive pressure-sensitive adhesive layer.
In the present invention, the “one surface of the substrate” means a substrate surface on the side to which a needle, a punch blade or a spindle are pressed or a substrate surface on which a laser beam is incident when forming a through hole. (Substrate surface 1a in FIGS. 1 to 3). Further, the substrate surface opposite to the one surface of the substrate is referred to as “the other surface of the substrate” (the substrate surface 1b in FIGS. 1 to 3).

Further, the total area of the through holes on one surface of the substrate is preferably 1 to 10%, more preferably 2 to 10%, still more preferably 3 to 10%, particularly preferably 3 to the area of the substrate. ~ 5%. By making the total area of the through holes with respect to the area of the base material within the above range, it is easy to ensure conductivity in the thickness direction (stacking direction) of the tape for continuity testing, and smoothness is also maintained and continuity testing is performed. Accuracy can be maintained.

The through-hole may be formed on the entire surface of the base material, or may be formed only in a range where an adherend (a chip or the like for continuity inspection) is attached.

Also, the difference (t1−t2) between the thickness (t1) of the base material at the peripheral portion of the through hole and the thickness (t2) of the base material other than the peripheral portion of the through hole shown in FIG. 4 is preferably 60 μm or less. More preferably, it is 30 μm or less, and further preferably 5 to 15 μm. When the through hole is formed by the above method, irregularities may be formed in the peripheral portion of the through hole on the other surface of the substrate. When the conductive adhesive layer to be described later is formed on the other surface of the substrate, the unevenness generated on the other surface of the substrate can be embedded, and a smooth conductive adhesive layer can be obtained. In this case, by setting the difference (t1-t2) within the above range, the unevenness of the other surface of the substrate can be reduced, and the effect can be obtained even when a thin conductive adhesive layer is formed. be able to. When the conductive pressure-sensitive adhesive layer is smooth, the inclination of the adherend adhered to the conductive pressure-sensitive adhesive layer is suppressed, the contact area of each adherend to the conductive pressure-sensitive adhesive layer becomes substantially constant, and the continuity test Improves accuracy. Moreover, the manufacturing cost of the continuity test tape can be reduced by reducing the thickness of the conductive adhesive layer.
By forming the through hole using laser light, the difference (t1−t2) can be easily within the above range. In addition, as shown in FIG. 4, the “thickness (t1) of the base material at the peripheral portion of the through hole” in the present invention is the thickness of the base material in the portion at the maximum height from the base material surface at the peripheral portion of the through hole. It is thickness. Further, “the thickness of the base material other than the peripheral portion of the through hole (t2)” is a substantial thickness of the base material.

Although the material of the base material in which the above through holes are formed is not particularly limited, for example, PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), PPS (polyphenylene sulfide), PI ( Polyimide), PEEK (polyetheretherketone), aramid, polylactic acid, or other resin insulating film is used. Among these, it is preferable to use PET, PBT, PEN, and PI from the viewpoints of heat resistance, followability, cost, and the like.

The substantial thickness of the substrate other than the peripheral portion of the through hole is not particularly limited, and is preferably 30 to 200 μm, more preferably 50 to 150 μm, and still more preferably 50 to 100 μm. If the thickness of the substrate is less than 30 μm, the substrate shrinks due to heat generated when the through hole is formed by laser light, and wrinkles may occur. On the other hand, when the thickness of the substrate exceeds 200 μm, the handling property in the manufacturing process of the continuity test tape may be deteriorated.

(Metal film)
The metal film is formed by vapor deposition or sputtering. The metal film formed by the vapor deposition method, the sputtering method, or the like covers one side of the substrate, preferably both sides of the substrate, and covers the peripheral side surface of the through hole. In addition, when a metal film is formed by a vapor deposition method, a sputtering method, or the like, the metal constituting the metal film may be filled in the through hole. As a result, the continuity test tape of the present invention has conductivity in the stacking direction (thickness direction). Such a metal film is not particularly limited, but is formed using, for example, aluminum, gold, silver, copper, platinum, nickel, or the like. In addition, when forming a metal film on one side of a base material, it is preferable to form a metal film on the base material surface 1a in FIG. 2, that is, “one side of the base material”. By forming a metal film on one surface of the base material, a smooth tape for continuity testing can be obtained, so that the accuracy of continuity testing is improved.

The thickness of the metal film is preferably 60 to 1000 nm, more preferably 100 to 500 nm, still more preferably 150 to 300 nm. By setting the thickness of the metal film in the above range, the conductivity in the thickness direction of the continuity test tape is excellent, and cracks in the metal film can be suppressed when the continuity test tape is handled. Moreover, the manufacturing cost of the continuity test tape can be reduced.

[Conductive adhesive layer]
The conductive adhesive layer is laminated on one side of the metal-coated substrate. An adherend can be favorably held by providing a conductive pressure-sensitive adhesive layer. Moreover, the adhesive composition which comprises a conductive adhesive layer penetrate | invades into a through-hole, and the electroconductivity of a thickness direction improves because it contacts a metal film. The surface on which the conductive pressure-sensitive adhesive layer is laminated is not particularly limited, but it is preferable to laminate the conductive pressure-sensitive adhesive layer on the substrate surface 1b side in FIG. 1, that is, on the “other surface of the substrate” side. When the conductive adhesive layer is laminated on the “other surface of the substrate” side, the conductive adhesive layer is laminated on the substrate surface 1a side in FIG. 1, that is, the “one surface of the substrate” side. As compared with the above, it is possible to reduce the influence of the unevenness generated on the “other surface of the base material” when forming the through hole on the handling property of the tape for continuity testing. In addition, by laminating a conductive pressure-sensitive adhesive layer on the other surface side of the base material, the unevenness can be embedded to obtain a smooth tape for continuity testing, improving the accuracy of continuity testing and conducting The handling property of the inspection tape can be improved. In addition, by reducing the thickness of the conductive pressure-sensitive adhesive layer, the manufacturing cost of the continuity test tape can be reduced.

The type of the pressure-sensitive adhesive that constitutes the conductive pressure-sensitive adhesive layer is not particularly limited, and may be formed of various conventionally known pressure-sensitive adhesives. As such an adhesive, for example, an adhesive such as rubber, acrylic, silicone, polyester, urethane, or polyvinyl ether is used. In addition, an energy ray curable pressure-sensitive adhesive that is cured by irradiation with energy rays and becomes removable, a heat-foaming type, or a water swelling type pressure-sensitive adhesive can also be used.

Among the above-mentioned pressure-sensitive adhesives, acrylic, polyester-based, and urethane-based pressure-sensitive adhesives are preferable, and acrylic pressure-sensitive adhesives are particularly preferable from the viewpoint of versatility and handleability.

Acrylic pressure-sensitive adhesives include, for example, (meth) acrylic acid ester homopolymers, copolymers containing two or more (meth) acrylic acid ester units, and (meth) acrylic acid esters and other functional monomers. What contains at least 1 sort (s) chosen from the copolymer with a monomer is used. Examples of the (meth) acrylate ester include butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, and (meth) acrylic. Acid nonyl, decyl (meth) acrylate, and the like can be mentioned. Examples of the functional monomer include hydroxyl group-containing monomers such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate, carboxylic acid group-containing monomers such as (meth) acrylic acid, (Meth) acrylamide, dimethyl (meth) acrylamide, N-vinylmorpholine, N-allylmorpholine, N- (meth) acryloylmorpholine and the like can be mentioned.

As one of the functional monomer components, N-vinyl morpholine, N-allyl morpholine, which is an ethylenically unsaturated monomer having a 6-membered heterocyclic ring each having a nitrogen atom and an oxygen atom, N- Use of (meth) acryloylmorpholine or the like is preferable because it exhibits performance as a crosslinking accelerator in the reaction with a crosslinking agent described later. Among these, N- (meth) acryloylmorpholine is preferably used from the viewpoint of good copolymerizability with other monomer components.

The conductive test tape is applied to an adherend such as a semiconductor chip, and is particularly affixed to a conductive adherend. Therefore, from the viewpoint of suppressing oxidation (corrosion) on the surface of the conductive adherend, it is preferable to use a pressure-sensitive adhesive that does not contain an acid group. For example, a pressure-sensitive adhesive that does not use a carboxylic acid group-containing monomer is preferable. On the other hand, from the viewpoint of the dispersibility of the conductive particles described later, it is preferable to use an adhesive containing an acid group.

The pressure-sensitive adhesive may be crosslinked with a crosslinking agent such as an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, or a chelate crosslinking agent. As the isocyanate-based crosslinking agent, tolylene diisocyanate (TDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), xylene diisocyanate (XDI), hydrogenated tolylene diisocyanate, diphenylmethane diisocyanate, trimethylolpropane-modified TDI, or the like is used. . As the epoxy-based crosslinking agent, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidylaniline, diglycidylamine and the like are used. Examples of the aziridine-based crosslinking agent include 2,2-bishydroxymethylbutanol-tris ト リ [3- (1-aziridinyl) pronate], 4,4-bis (ethyleneiminocarboxyamino) diphenylmethane, tris-2,4,6- (1 -Aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) aziridinyl] phosphine oxide, hexa [1- (2-methyl) -aziridinyl] triphosphatriazine and the like are used. As the chelate-based crosslinking agent, aluminum chelate, titanium chelate or the like is used. By appropriately adjusting the amount of the crosslinking agent, it is possible to develop the necessary adhesive properties for various adherends. A crosslinking agent may be used not only alone but also in combination of two or more as required.

In the pressure-sensitive adhesive composition constituting the conductive pressure-sensitive adhesive layer, conductive particles are preferably blended in addition to the pressure-sensitive adhesive. By adding conductive particles to the conductive pressure-sensitive adhesive layer, conductivity can be imparted to the pressure-sensitive adhesive layer.

The conductive particles used in the present invention include carbon black and graphite such as furnace black and acetylene black, or metal such as carbon fiber, conductive whisker, conductive ceramic powder or nickel, copper, gold, silver, iron and chromium. One or more of the particles are used.

Further, the pressure-sensitive adhesive composition forming the conductive pressure-sensitive adhesive layer has additives generally contained in pressure-sensitive adhesives for ordinary pressure-sensitive adhesive sheets, such as tackifiers, ultraviolet absorbers, antioxidants, Or a coloring agent etc. may be contained as needed.

When the conductive test tape of the present invention configured as described above is applied to an adherend, the conductive adhesive layer comes into contact with the adherend, and the adherend and the conductive test tape are electrically connected. . Therefore, since it can conduct | electrically_connect in a lamination direction (thickness direction) and a surface direction, a conduction inspection can be performed simply.

The thickness of the conductive pressure-sensitive adhesive layer is not particularly limited, and the difference (t1) between the adhesive strength and the thickness (t1) of the base material at the peripheral portion of the through hole and the thickness (t2) of the base material other than the peripheral portion of the through hole. It is preferably set according to -t2). The thickness of the conductive pressure-sensitive adhesive layer is preferably 10 to 80 μm, more preferably 15 to 50 μm, and still more preferably 20 to 35 μm. By setting the thickness of the conductive pressure-sensitive adhesive layer within the above range, the difference (t1-t2) can be embedded by the conductive pressure-sensitive adhesive layer. Therefore, a thin pressure-sensitive adhesive layer is formed on the metal-coated substrate. Can also obtain a smooth pressure-sensitive adhesive layer.

The conductive pressure-sensitive adhesive layer preferably has an appropriate removability to the adherend, and the adhesive strength to the adherend is preferably 1000 to 7000 mN / 25 mm, more preferably 2000 to 6000 mN / 25 mm, Preferably, it is 2500 to 5000 mN / 25 mm. When the adhesive strength of the conductive pressure-sensitive adhesive layer is in the above range, the adherend can be held well and the adherend can be easily peeled after the inspection. In accordance with JIS Z 0237; 2009, the adhesive strength is an adhesion by a 180 ° peeling method at 23 ° C. and 50% relative humidity of a continuity test tape after being attached to an adherend (SUS) after 30 minutes. It is power.

In the continuity test tape of the present invention, a release sheet may be laminated on the surface of the pressure-sensitive adhesive layer in order to protect the conductive pressure-sensitive adhesive layer before use. You may use a peeling sheet as it is, without peeling the peeling sheet used at the time of manufacture of the tape for a continuity test of this invention mentioned later from an adhesive layer.

There is no restriction | limiting in particular as a peeling base material in a peeling sheet, It can select suitably from various base materials conventionally known as a base material of a peeling sheet. Examples of such release substrates include polyester films such as PET, PBT, and PEN, polyolefin films such as polypropylene and polymethylpentene, plastic films such as polycarbonate films and cellulose acetate films, and laminated sheets containing these. Can be mentioned. The thickness of the release substrate is not particularly limited, but is usually preferably 10 to 150 μm.

When using a plastic film as the release substrate of the release sheet, if desired, for the purpose of improving the adhesion between the plastic film and the release agent layer, on the side of the plastic film on which the release agent layer is provided, if desired. Further, a physical or chemical surface treatment such as an oxidation method can be performed. Examples of the oxidation method include corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, and ozone / ultraviolet irradiation treatment. These surface treatment methods are appropriately selected depending on the type of the release substrate, but in general, the corona discharge treatment method is preferably used from the viewpoints of effects and operability. Moreover, primer treatment can also be performed.

The release agent for forming the release agent layer in the release sheet is silicone resin, long chain alkyl resin, alkyd resin, fluororesin, polybutadiene rubber, butyl rubber, styrene-butadiene copolymer, polyisoprene rubber, ethylene polypropylene copolymer. And rubber-based elastomers.

Coating of the release agent on the release substrate is conventionally known, for example, bar coating method, reverse roll coating method, knife coating method, roll knife coating method, gravure coating method, air doctor coating method, doctor blade coating method, etc. It can be performed by a coating method. The thickness of the release agent layer is not particularly limited, but is usually preferably 0.01 to 5 μm.

Next, a method for manufacturing a continuity test tape according to the present invention will be described.

In the first manufacturing method according to the present invention, first, a base material provided with a plurality of through holes is prepared. Next, a metal film is formed on the surface of the base material using a vapor deposition method, a sputtering method, or the like to obtain a metal-coated base material. The metal film is preferably formed by a vapor deposition method from the viewpoint of ease of manufacture and uniformity of the metal film. Thereafter, a conductive pressure-sensitive adhesive layer is laminated on the surface of the metal-coated substrate. The method of laminating the pressure-sensitive adhesive layer is as follows. The pressure-sensitive adhesive is diluted with an appropriate solvent as necessary to obtain a pressure-sensitive adhesive composition, and applied onto the release sheet and dried to give a predetermined dry film thickness. A layer may be formed and transferred to the surface of the metal-coated substrate, or the pressure-sensitive adhesive composition may be directly applied to the surface of the metal-coated substrate and dried to form a pressure-sensitive adhesive layer. In this way, the continuity test tape according to the present invention is obtained.

Moreover, in the second manufacturing method according to the present invention, first, a conductive pressure-sensitive adhesive layer is laminated on the surface of a base material provided with a plurality of through holes. The method for laminating the pressure-sensitive adhesive layer is the same as described above. Thereafter, a metal film is formed on one surface of the substrate (the surface opposite to the surface on which the pressure-sensitive adhesive layer is laminated) using a vapor deposition method, a sputtering method, or the like to obtain a metal-coated substrate. Thus, the tape for continuity testing according to the present invention can be obtained.

The tape for continuity testing according to the present invention has continuity in the laminating direction and the surface direction, and can easily inspect the continuity of a semiconductor chip or the like.

Next, a continuity test method using the continuity test tape according to the present invention will be described.

In the continuity test method of the present invention, the adherend is affixed to the conductive adhesive layer of the continuity test tape of the present invention, and then the conductive adhesive layer or metal film (conductivity) of the adherend and the continuity test tape. A tester probe is brought into contact with the surface opposite to the adhesive layer) to inspect the conductivity of the adherend. Since the tape for continuity testing of the present invention has conductivity in the laminating direction, it is preferable to inspect the conductivity in the laminating direction by bringing one tester into contact with the adherend and the other tester in contact with the metal film. More preferably, the tester is brought into contact with the metal film in a range where the adherend is adhered and the conductivity is inspected in the stacking direction (substantially vertical direction). According to the method for inspecting continuity in the stacking direction, it is easy to keep the distance between the testers substantially constant, and the continuity test can be performed easily while being excellent in accuracy of the continuity test.

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to these examples. “Diameter of through-hole”, “ratio of total area of through-hole to base-material area”, “thickness (t1) of base material in peripheral portion of through-hole, and peripheral portion of through-hole in examples and comparative examples below The difference (t1−t2) from the base material thickness (t2) ”,“ handling property ”,“ continuity test ”,“ chip tilt ”,“ adhesive strength ”and“ tack ”in the cases other than the above were evaluated as follows. .

<Diameter of through hole>
The diameter of the through hole was measured by observing the surface using a scanning electron microscope (Scanning Electron Microscope (SEM) VE-9800 manufactured by Keyence Corporation).

<Ratio of the total area of the through holes to the substrate area>
Count the number of through-holes formed in the substrate, and calculate the total area of the through-holes from the diameter of the through-holes on one side of the substrate measured as described above. The percentage was determined.

<Difference (t1−t2) between the thickness (t1) of the base material at the peripheral portion of the through hole and the thickness (t2) of the base material other than the peripheral portion of the through hole>
The base material in which the through hole is formed is observed with a laser microscope (VHS-1000 manufactured by Keyence Corporation), and the thickness (t1) of the base material at the peripheral part of the through hole and other than the peripheral part of the through hole The thickness (t2) of the base material was measured. In addition, as shown in FIG. 4, the thickness (t1) of the base material in the peripheral portion of the through hole was the thickness of the base material in the portion having the maximum height from the base material surface in the peripheral portion of the through hole. Moreover, the thickness (t2) of the base material other than the peripheral edge portion of the through hole is substantially the same as the thickness of the base material.

<Handling>
A 15 cm square continuity test tape was wrapped around a 5 cm diameter polyethylene rod and then checked for creases and curls. The case where no crease or curl occurred in the continuity test tape was evaluated as “good”, and the case where a crease or curl occurred was evaluated as “bad”.

<Continuity test>
The chip on which the electrode was formed was affixed to the conductive adhesive layer of the continuity test tape. After that, the probe on the tester (KIT-60, manufactured by Sanwa Denki Keiki Co., Ltd.) is brought into contact with the electrode on the chip and the metal film of the tape for continuity testing (the surface opposite to the conductive adhesive layer). Inspected. A continuity test is performed on 100 chips attached to the conductive adhesive layer, and “A” indicates that 100 chips are connected, and “B” indicates that the number of chips is 70 to 99. The case of 0 to 69 was evaluated as “C”.

<Tilt tilt>
A semiconductor chip (1 mm × 1 mm, thickness 200 μm) is attached to the conductive adhesive layer, and the angle between the chip and the adhesive layer (angle α shown in FIG. 3) using a laser microscope (VHS-1000 manufactured by Keyence Corporation). Was measured.

<Adhesive strength>
In accordance with JIS Z 0237; 2009, the adhesive strength was measured by a 180 ° peeling method at 23 ° C. and 50% relative humidity of a continuity test tape after 30 minutes after being attached to an adherend (SUS). .

<Tack>
The pressure-sensitive adhesive layer surface was touched with a finger to confirm the presence or absence of tack.

(Example 1)
[Preparation of substrate]
Two shot burst processing (repetition frequency: 10000 Hz, pulse width: 25 μs) using a CO ₂ laser (CO ₂ laser processing machine “YB-HCS03” manufactured by Panasonic Welding Systems Co., Ltd.) on a 100 μm thick PET film ) / 50 μsec (second shot)), through-holes were formed to obtain a substrate. The ratio of the total area of the through holes to the substrate area was 3%.

[Formation of metal film]
By using a vapor deposition method (deposition rate: 2 Å / sec, film thickness: 200 nm, resistance heating conditions: 40 A, 2.0 V) on both surfaces of the base material obtained above, aluminum is formed to a film thickness of 200 nm. And a metal coated substrate was obtained.

[Preparation of pressure-sensitive adhesive composition]
For 100 parts by mass of acrylic adhesive (butyl acrylate / acrylic acid = 95/5 (mass ratio), weight average molecular weight = 600,000), 12 parts by mass of conductive particles (Lion's carbon black) and isocyanate crosslinking agent ( 0.1 part by mass of Toyo Ink Co., Ltd. BHS-8515) was mixed in a solvent to obtain an adhesive composition. The weight average molecular weight is obtained using a commercially available molecular weight measuring instrument (main product name “HLC-8220GPC”, manufactured by Tosoh Corporation; column product name “TSKGel SuperHZM-M”, manufactured by Tosoh Corporation; developing solvent tetrahydrofuran). (The same applies hereinafter). Moreover, even if a mass part is a thing of the packing form diluted with a solvent, all are values of solid content conversion (hereinafter, the same).

[Preparation of tape for continuity test]
The above pressure-sensitive adhesive composition is applied to a release sheet (SP-PET 381031LK manufactured by Lintec Corporation) so that the thickness after drying is 35 μm (drying conditions: 100 ° C., 1 minute), and formed on the release sheet. Thus obtained conductive adhesive layer was obtained. Next, the conductive pressure-sensitive adhesive layer and the metal-coated substrate were bonded together to obtain a continuity test tape. Each evaluation was performed by removing the release sheet. The results are shown in Table 1. In addition, the conductive adhesive layer was laminated | stacked on the opposite side (the other surface side of a base material) of the base material surface by which the laser beam enters.

(Example 2)
In the preparation of the pressure-sensitive adhesive composition, a continuity test tape was obtained in the same manner as in Example 1 except that the amount of conductive particles added was 15 parts by mass. The results are shown in Table 1.

(Example 3)
In the production of the pressure-sensitive adhesive composition, the same electrical conductivity as in Example 1 was used except that nickel metal particles (HCA-1 manufactured by Vale Japan Co., Ltd.) were used as the conductive particles and the addition amount was 75 parts by mass. A test tape was obtained. The results are shown in Table 1.

(Example 4)
In the production of the pressure-sensitive adhesive composition, the same as in Example 1 except that nickel metal particles (# 255 manufactured by Novamet Specialty Products Corporation) were used as the conductive particles and the addition amount was 60 parts by mass. I got a tape. The results are shown in Table 1.

(Example 5)
In the production of the base material, a continuity test tape was obtained in the same manner as in Example 1 except that the number of through holes formed was increased and the ratio of the total area of the through holes to the base material area was 8%. . The results are shown in Table 1.

(Example 6)
In the formation of the metal film, a continuity test tape was obtained in the same manner as in Example 1 except that the film thickness of aluminum was 60 nm. The results are shown in Table 1.

(Example 7)
In the formation of the metal film, a continuity test tape was obtained in the same manner as in Example 1 except that the film thickness of aluminum was 900 nm. The results are shown in Table 1.

(Example 8)
In the production of the base material, a continuity test tape was obtained in the same manner as in Example 1 except that a base material was obtained by forming a through hole in a 100 μm thick PET film using a needle (silk needle No. 5). It was. The results are shown in Table 1.

Example 9
In the formation of the metal film, a continuity test tape was obtained in the same manner as in Example 1 except that the film thickness of aluminum was 500 nm. The results are shown in Table 1.

(Example 10)
In the production of the base material, a continuity test tape was obtained in the same manner as in Example 1 except that the number of through holes formed was increased and the ratio of the total area of the through holes to the base material area was 5%. . The results are shown in Table 1.

(Example 11)
In the production of the base material, a continuity test tape was obtained in the same manner as in Example 1 except that the number of through holes formed was increased and the ratio of the total area of the through holes to the base material area was 10%. . The results are shown in Table 1.

Example 12
A continuity test tape was obtained in the same manner as in Example 8 except that the diameter of the through-hole formed was changed in the production of the substrate. The results are shown in Table 1.

(Comparative Example 1)
A continuity test tape was obtained in the same manner as in Example 1 except that a rolled copper foil having a thickness of 35 μm without a through hole was used as the substrate. The results are shown in Table 2.

(Comparative Example 2)
A continuity test tape was obtained in the same manner as in Example 1 except that a 50 μm thick aluminum foil without through holes was used as the substrate. The results are shown in Table 2.

(Comparative Example 3)
In the formation of the metal film, a continuity test tape was obtained in the same manner as in Example 1 except that the film thickness of aluminum was 50 nm. The results are shown in Table 2. In Comparative Example 3, since an extremely thin metal film was formed, a metal film continuous on the peripheral side surface of the through hole could not be formed, and as a result, it was considered that the conductivity in the thickness direction could not be obtained.
Whether or not a metal film was formed on the peripheral side surface of the through hole was confirmed as follows.
Cutting the continuity test tape and observing the cross section using a scanning electron microscope (Scanning Electron Microscope (SEM) VE-9800 manufactured by Keyence Corporation), an energy dispersive X-ray spectrometer manufactured by Ametech Corporation ( X-ray analysis of the cross section was performed using EDX). Element mapping measurement was performed, and it was confirmed whether or not Al element was present on the peripheral side surface of the through hole and that Al element was not present in the other cross section of the tape for continuity testing.
In the continuity test tape of Comparative Example 3, it was confirmed that no Al element was present on the peripheral side surface of the through hole, and no Al element was present on the other cross sections.
In the continuity test tapes of Examples 1 to 12, it was confirmed that Al element was present on the peripheral side surface of the through hole and Al element was not present on the other cross sections.

10: Tape for continuity test 1: Base material 2: Metal film 3: Conductive adhesive layer 4: Through hole 5: Semiconductor chip 6: Metal-coated base material

Claims (7)

A laminate comprising a base material provided with a plurality of through holes and a metal-coated base material made of a metal film, and a conductive pressure-sensitive adhesive layer,
Tape for continuity testing that has conductivity in the stacking direction. The tape for continuity testing according to claim 1, wherein a difference t1-t2 between the thickness t1 of the base material at the peripheral portion of the through hole and the thickness t2 of the base material other than the peripheral portion of the through hole is 60 µm or less. The continuity test tape according to claim 1 or 2, wherein the through hole is formed by laser light. 4. The continuity testing tape according to claim 1, wherein the metal film has a thickness of 60 to 1000 nm. The tape for continuity testing according to any one of claims 1 to 4, wherein the total area of the through holes on one surface of the substrate is 1 to 10% with respect to the area of the substrate. 6. The continuity testing tape according to claim 1, wherein the conductive adhesive layer has removability. A continuity test method using the continuity test tape according to any one of claims 1 to 6.

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