TW486766B - Film carrier tape for mounting electronic parts, and method for manufacturing the same - Google Patents

Abstract

A film carrier tape for mounting electronic parts has an insulating film. On which a copper foil is laminated, the copper foil being etched to form a desired circuit pattern. By plating tin over the almost entire circuit, a copper-diffused tin plating layer (a) is formed. On the desired positions of circuit pattern other than then terminal portions, a protective layer of hardened solder resist is formed. The terminal portions are provided with a tin-plating layer (b) substantially free of copper over the surface of the upper-diffused tin plating layer (a). More preferably, a copper tin-containing zone is provided between the copper-migrated tin-plating layer (a) and the pure tin plating layer (b).

Description

486766

Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 V. Invention Description (1), [Technical Field of the Invention] The present invention relates to a film-shaped mounting tape (TAB (Tape Automated Bonding) for assembling electronic components such as 1C or LSI) , Tape and tape automatic bonding) tape, T_BGA (Tape Ball Grid Array) tape, ASIC (Application Specific Integrated Circuit, special application integrated circuit) tape and so on) and manufacture of this carrier tape Method. In more detail, the present invention relates to a tape-like mounting tape (TAB (Tape Automated Bonding)), T -BGA (Tape Ball Grid Array), tape reel, ASIC (Application Specific Integrated

Circuit, special application integrated circuit) tape reel, etc.) and method of manufacturing the carrier tape. [Technical Background of the Invention] In recent years, electronic devices such as notebook computers have become smaller and lighter. In addition, the wiring of the semiconductor 1C is further miniaturized. With the miniaturization of such electronic devices, TAB tapes, electronic tapes, T-BGA tapes, and ASIC tapes have been widely used. The tendency of film-like mounting tapes for part assembly. This film-shaped mounting tape for assembling electronic components was manufactured as follows. For example, a copper foil is affixed to a base material film such as polyimide, and a photoresist is etched on the surface of the copper foil, and a portion other than the wiring pattern to be formed by the photoresist is exposed and removed. Exposure Photoresistance Flux. Next, the photoresist solder is removed by etching to further remove the photoresist solder to form a wiring pattern. In this way, except for the inner leads on the film-shaped mounting tape for the assembly of electronic parts with the wiring pattern formed ^ ----------------- ^ (Please read the precautions on the back before filling (This page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 1 310966 486766 A7 —-----_—____ V. Description of the invention (2) or connection parts such as solder ball terminals A sokter resist is applied as a circuit protective layer. After the solder resist is applied in this manner, a tin plating layer is formed on the connection portion of the exposed portion. However, when the solder resist is applied in this way, when it is dried and hardened and tin-plated, the plating solution will invade from the end of the solder resist along the wiring pattern and under the solder resist to form a local battery and dissolve the steel in this part. Out. That is, as shown in FIG. 2, after the copper foil 3q is pasted with the adhesive layer 12 on the base material 10 and the wiring pattern 30 is formed as usual, the solder resist 20 is applied and dried and hardened. When the tin plating layer 31 is formed on the wiring pattern 30, the plating solution will invade from the end 2 of the solder resist 20 to the bottom of the solder resist 20 and form a local battery here, and the steel foil in this part will be dug into a trench shape. Pitting. The cutout (cutout) is shown in FIG. 2 as 3 5. When a bending stress is applied to the film-shaped carrier tape for assembling an electronic part with the cutout 35 formed thereon, the stress is concentrated on the cutout 35, and in the worst case, the lead may be broken. The Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed on the end of the solder resist 3 () to prevent the plating solution from intruding into it. In a flexible circuit board having a conductive pattern formed on a film as a base material, a flexible circuit board characterized by coating a pattern with a solder resist applied for the purpose of protecting a circuit and then coating the pattern, and a method of manufacturing the same ". According to the invention described in the above publication, since this manufacturing method applies a solder resist after plating and heat-hardens it, the plating solution does not invade under the solder resist, and it is hardened by the solder resist. The time of heating also heats the tin plating layer, so there is no need to re-apply the Chinese paper standard (CNS) A4 specification (21〇X 297 public love) for this paper. 2 310966 310966 486766 V. Description of the invention (3) A heating step to prevent the occurrence of whiskers. However, in the actual process, it is difficult to continuously perform the plating step and the heating and hardening step of the solder resist. In fact, it is applied to the ribbon obtained through the plating step. Flux, which in turn heat-hardens the solder resist. In order to suppress the growth of whiskers, it is necessary to heat treat the power deposit immediately after the power mine, and the whiskers will grow over time. Furthermore, the temperature conditions when the solder resist is heat-hardened and the temperature conditions for suppressing the growth of whiskers are not the same. When one of the conditions is used for heating, there is a problem that the other effect cannot be fully obtained. Furthermore, using this heat treatment to suppress the growth of whiskers' Although autumn is very useful in a short period of time, after a long period (for example, 2 to 3 months), the effect of preventing whisker will be reduced. . However, as a method of suppressing the growth of whiskers, as described above, a method of heating (tempering) the ore tin layer after ore tin is performed to diffuse copper in the hafnium layer is known. If you use this method, you can prevent the occurrence of 4 crystals to a certain extent in a short period of time, but this method has the problem that you cannot prevent the growth of whiskers in a long period of time, such as 2 to 3 months. A method for suppressing the growth of such whiskers is disclosed in Japanese Patent Application Laid-Open No. 5_33187, which states that "when ore tin is applied to a fine pattern of steel or copper alloy, the thickness ㈢" is first applied, h Jiajiao :::: The pure tin layer is all used as a diffusion layer with the steel bottom layer: ',

"The surface is tin-plated" to form a pure tin-plated thickness of 0. The invention is characterized by tin plating whiskers whose m is characterized by 0.8V. That is, the "tin layer" described in this bulletin, and the heat treatment of this mineral tin paper scale makes copper expand

• nn 1 «(Please read the note on the back? Matters before filling out this page) -H 1 H--III----- Order ----- --line · 486766 Employee Property Cooperatives, Intellectual Property Bureau, Ministry of Economic Affairs Printed 4 310966 A7 V. Description of the invention (4) After being scattered in the tin plating layer, 'plating (rapid plating) is performed again, and a pure tin plating layer is formed on the surface of the tin plating layer where copper is diffused to prevent whisker formation. . However, in the method disclosed in this publication, a solder resist is applied to a wiring pattern and hardened, and then ore tin is further processed by heat treatment to diffuse the steel into the tin plating layer. A tin plating layer was formed on the surface of the tin layer again. Therefore, although the invention described in this publication can control the formation of whiskers ^, since the plating is performed after the solder resist is applied and hardened, the same plating solution as the conventional plating still exists and the solder will penetrate into the solder resist. The problem is that the cutout 35 is formed below. [Objective of the Invention] An object of the present invention is to provide a film-shaped mounting for electronic component assembly that does not form a cutout portion on a wiring pattern even if an electroless plating solution is formed, and can suppress the growth of whiskers over a long period of time. Tape and method for manufacturing the film-shaped mounting tape for electronic component assembly. [Summary of the Invention] The film-shaped mounting tape for electronic component assembly of the present invention (the 臈 -shaped mounting tape for the first electronic component assembly) is made by attaching a steel foil to an insulating film and etching the steel box to form a desired A wiring pattern is characterized in that tin is plated on substantially the entire wiring pattern to form a tin-plated layer (a) with copper diffusion, and a solder resist is formed at a predetermined position other than the terminal portion of the wiring pattern. The protective layer formed by the hardened body, and at the same time, a tin-plated layer (b) containing substantially no copper is formed on the surface of the tin-plated layer (a) having steel diffusion on the terminal portion. The above-mentioned film-shaped mounting tape for the assembly of electronic parts of the present invention (the first film-shaped mounting tape for the assembly of the first electronic parts) is adhered to the insulating film with copper foil, and the etched scale is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 public love) " " ---- ---_----------------- Order --------- (Please read first (Notes on the back then fill out this page) 486766

Printed by A7 ______B7____, Consumer Cooperatives, Bureau of Intellectual Property, Ministry of Economic Affairs. 5. Description of the Invention (5) After the copper foil is engraved to form a desired wiring pattern, and a steel-plated tinned layer (a) is formed on the entire wiring pattern, A predetermined portion other than the terminal portion of the wiring pattern is coated with a solder resist and hardened, and after the solder resist is hardened, the terminal portion of the wiring pattern is tin-plated again to form tin plating that does not substantially contain copper. Layer (b). The film-shaped mounting tape for the assembly of electronic parts (the film-shaped mounting tape for the assembly of the second electronic parts) of the present invention is a copper foil adhered to an insulating film, and the copper foil is engraved to form a desired wiring pattern. It is characterized by forming a tin-plated layer (a) having a copper diffusion by tin plating on substantially the entire wiring pattern, and forming a hardened body made of a solder resist at a predetermined position other than the terminal portion of the wiring pattern. The formed protective layer also has a copper-diffused tin plating layer (a) on the terminal portion, and the copper diffusion concentration is directed from the surface of the copper-diffused tin plating layer (a) to a tin-plated layer that does not substantially contain copper. (B) A copper-tin-containing area having a gradually decreasing surface, and this area is formed continuously with the tin plating layer (b) which does not substantially contain copper. The above-mentioned film-shaped mounting tape for electronic component assembly (the second film-shaped mounting tape for electronic component assembly) of the present invention has a copper foil adhered to an insulating film, and the copper foil is etched to form a desired wiring pattern. Furthermore, the entire wiring pattern formed is tin-plated, and a solder resist is applied to a predetermined portion other than the terminal portion of the wiring pattern to harden it. After the solder resist is hardened, the terminal portion of the wiring pattern is hardened. The tin plating step is performed again, and is characterized in that a copper-diffused tin-plated layer (a) is formed on the terminal portion, and the copper diffusion concentration from the surface of the tin-plated layer (a) with steel diffusion does not substantially contain This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 5 310966 --------------------- ^ ------- -(Please read the precautions on the back before filling out this page) 6 A7 _B7 V. Description of the invention (6 Copper money tin layer (b) The copper and tin containing area on the surface gradually decreases, and this area is essentially the same as Continuous formation of a tin-free layer (b) that does not contain steel. The 臈 -shaped mounting tape for assembling electronic parts of the present invention A tin plating layer 形成 is formed on the surface of the t wiring pattern formed by a copper pig coated with a solder resist, and the tin plating layer ⑷ is used to diffuse copper from the wiring pattern by heating to form a tin-copper diffusion layer. After the tin plating layer (a) is formed in this manner, a solder resist is applied to a desired position on the surface of the tin plating layer 除了 except for the electrode joint portion, and the solder resist is dried and hardened. In this way, the solder resist is hardened. After that, the "re-use of tin" was used to form a tin-plated layer (b) that does not substantially contain copper on the surface of the tin layer ⑷. The carrier tape thus formed did not exist during the first tin plating. Solder resist, so it will not be formed on copper due to the formation of local batteries ^ And when tin plating is performed for the first time, tin / steel diffusion can be formed on the copper surface even if the plating solution will enter the solder underneath the solder resist. Layer, and steel Vb will not come into contact with the plating solution, so a local battery using steel as an electrode will not be formed, and therefore, a cutout 35 as shown in FIG. 2 will not be formed. After tinning once, hardened by solder resist The protective layer formed by the object, secondly, by performing a second tin plating, the growth of the whiskers can be suppressed and a short circuit caused by the whiskers can be prevented. Regarding the mechanism for forming the cutout 35 shown in FIG. 2 The entire content cannot be explained yet, but the present inventor believes that the excavation portion 35 can be formed as described below by forming a local battery. Fig. 3 is a model showing the mechanism of the excavation portion 35 due to the formation of the local battery. Figure. First, when the plating solution invades from the end of the solder resist to the bottom of the anti-tan agent, the paper size is subject to the Chinese National Standard (CNS) A4 specification ⑽χ tear public hair) 310966 (Please read the precautions on the back before filling this page ) Then fill in too 486766 A7 ------- 5. In the description of invention (7), due to the shrinkage force (internal stress) remaining in the solder resist, the solder resist will float and a plating solution will be formed. Liquid accumulation. In this plating solution, tin is in a form containing tin borofluoride, etc., and an electrochemical substitution reaction is started between tin and copper metal, and the copper ions that have been substituted are retained in a liquid deposit.

(Please read the precautions on the back before filling out this page.) In order to electrically neutralize the retained positive steel ions, anions (such as borofluoride ions) in the plating layer are moved. At the end of the solder resist, positive tin ions remain due to the movement of the anions, and steel ions receive electrons from the dissolution part to precipitate metallic tin. By dissolution of steel ions, anions, and electrons, tin is precipitated in a chain to form a local battery with a copper elution portion as the anode and a tin precipitation portion as the cathode. It can be considered that the wiring pattern formed by the copper foil under the solder resist is partially dissolved by the above-mentioned mechanism to form a cutout.

Although the terminal portion of the film-shaped mounting tape for electronic component assembly of the present invention is formed with the copper-diffused mineral tin layer (a) and the tin-plated layer (b) that does not substantially contain steel as described above, Two film-like carriers for the assembly of electronic parts are formed on a tin-plated layer (a) (steel-diffused tin-plated layer (a)) with steel diffusion and a tin-plated layer (b) (pure tin-plated layer) that does not substantially contain steel. Between (b)), a steel-tin-containing region is formed in which the diffusion concentration gradually decreases from the surface of the tin-plated layer with steel diffusion toward the surface of the tin-plated layer (b) that does not substantially contain steel. That is, the film-shaped mounting tape for assembling the electronic parts of the present invention is attached to the film of the absolute film, and the steel film is engraved to form a desired wiring pattern. Approximately the entire surface is tin plated ^ Zhang ruler ^ iiii? _ (CNS) A4 specifications ⑵0 x 297 public love Γ 310966 486766 8 A7 B7 5. Description of the invention (8) to form a tin-plated layer with copper diffusion (a ), And a protective layer made of a hardened body of a solder resist is formed at a predetermined position other than the terminal portion of the wiring pattern, and a steel-diffused tin plating layer (a) and copper diffusion are formed on the terminal portion. A copper-tin-containing area whose concentration gradually decreases from the surface of the tin-plated layer (a) with copper diffusion toward the surface of the tin-plated layer (b) that does not substantially contain copper, and this area is similar to the tin-plated layer that does not actually contain copper Layer (b) is formed continuously. The second film-shaped mounting tape for assembling electronic components of the present invention has a copper pig on an insulating film, and the steel foil is etched to form a desired wiring pattern. The whole is tin-plated, and a resist is coated and hardened on a predetermined portion other than the terminal portion of the wiring pattern. After the solder resist is hardened, the terminal portion of the wiring pattern is tin-plated again. It is characterized in that a copper-diffused tin plated layer (a) is formed on the terminal portion, and the surface of the tin-plated layer (a) with a copper diffusion concentration from the surface of the copper-diffusion layer (a) faces the tin-plated layer (b) that does not substantially contain copper. The steel-tin-containing area gradually decreasing in surface, and the area is formed continuously with the tin-plated layer (b) which does not substantially contain steel. In this way, by continuously forming a copper-tin-containing region where the copper concentration is continuously reduced from the steel diffusion tin plating layer (a) to the pure tin plating layer (b) and the pure tin plating layer, it is more difficult to form the above-mentioned excavation. At the same time, it can be both permanent and almost completely prevent the formation of whiskers. [Specific description of the invention] Next, a film-shaped mounting tape for assembling an electronic component according to the present invention will be described in detail along a manufacturing method with reference to a drawing. In addition, as shown in the figure below, if the components are common, the common component numbers are noted. The paper size applies the til national standard (CNS) A4 specification (210x 297 public love "310966 ------- ------------ Order ---------- (Please read the notes on the back before filling this page)

486766 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Description of the Invention (9) The first diagram is a cross-sectional view of a model showing the cross section of the film-shaped mounting tape for assembling electronic parts of the present invention. In the film-shaped mounting tape 1 for assembling an electronic part of the present invention, an insulating film 10 and a wiring pattern 30 formed of an electrolytic steel foil adhered to this surface by, for example, an adhesive layer 12 are sequentially laminated. Then, this wiring pattern 30 is coated with a layer (hardened material) formed of the solder resist 20 to protect the surface. The insulating film 10 constituting the film-shaped mounting tape for assembling an electronic component of the present invention is formed of a flexible resin film. This insulating film 10 is in contact with fee or the like during etching, and therefore has chemical resistance that is not invaded by such chemicals, and heat resistance that does not deteriorate even when heated during bonding. Examples of the resin forming such a flexible resin ray include glass epoxy resin, B-butyl resin, polyester, polyamide, and polyamide. Particularly, in the present invention, it is preferable to use a film made of polyimide. Examples of the polyimide constituting the insulating film 10 include a wholly aromatic polyamidoamine synthesized from pyromellitic acid dianhydride and an aromatic diamine, and a biphenyltetracarbonic dianhydride Fully aromatic amidine of biphenyl skeleton synthesized with aromatic diamine group. In particular, it is better to use a fully aromatic polyamidine (for example, trade name: UPLEX, manufactured by Ube Kosan Co., Ltd.) with bibenzuki wood in this sun and moon towel. The thickness of such an insulating film 10 is usually in the range of 25 to 125 # m, and preferably in the range of 50 to 75 "m. The insulating film 10 is formed in a punching step. Device hole, sprocket hole, cut-out hole for external lead, etc. This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 9 310966

Installation --- (Please read the precautions on the back before filling in this page). · --- Line · 486766 A7 __B7 V. Description of the invention (10) The wiring pattern 30 'is on the insulating film 形成 formed with the predetermined hole as described above. An insulating adhesive is applied to form an adhesive layer 12, and a copper foil is adhered by using the adhesive layer 12, and is formed by etching the copper foil. Although the steel foil here may be any of electrolytic steel foil and rolled steel foil, it has recently been made to use electrolytic copper foil that can achieve fine pitch. When sticking copper foil, you don't need to use adhesive, or you can use adhesive. The adhesive used here is preferably one having properties such as heat resistance, chemical resistance, adhesion, and flexibility. Examples of the adhesive having such characteristics include an epoxy-based adhesive and a phenol-based adhesive. Such an adhesive may be a denatured resin such as urethane resin, melamine resin, or polyvinylidene resin, or a rubber denatured epoxy resin itself. This kind of adhesive is heat-hardening. The thickness of such an adhesive layer is usually in the range of 8 to 23 ㈣, and the more preferable range is in the range of PD to 21 mm. The adhesive layer 12 composed of such an adhesive may also be coated on the surface of the insulating film 10 or on the surface of the electrolytic copper foil. The electrolytic steel foil used here can be a copper box with a thickness generally used in the manufacture of film-shaped mounting tapes for electronic component assembly, but in order to manufacture film-shaped mounting tapes for macro electronic component assembly, steel reeds Steel reeds which are usually used in the range of 6 to 25 / zm, and more preferably in the range of today to ^ are more desirable. With such a thin electrolytic steel foil, a narrow-pitch inner lead can be easily formed. After the copper drop is pasted on the surface of the insulating film in this manner, a photoresistive tanning agent (hereinafter referred to as a photoresist) is coated on the surface of the copper drop, and the paper size applies the Chinese national standard (CNS) for this photoresist. ) A4 size (210 X 297 public love) 10

310966 486766 A7

A7 5. Description of the invention (U). From this point of view, 1 tin layer _ of # ^ ^ or more is preferred. 1 ... on the better. .3 = upper 'and the upper limit of the thickness of this layer 31 is usually 0 & The ore tin layer ⑷31 is formed on the entire surface of the wiring pattern except that the interface with the adhesive 12 is removed. ,, "pattern Note

By spreading copper on the ore tin layer ⑷31 thus formed, whisker formation can be prevented. A method of diffusing steel on the ore tin layer ⑷31 includes a method of simultaneously heating the tin plating layer ⑷31 and the wiring pattern. At this time, the second degree is usually 70i 200t, preferably 100 to 15 generations, and the time between heating is also determined by the thickness of the mineral tin ', but it is usually 30 seconds to 120 minutes, and preferably 30 minutes. To 60 minutes. By heating in this way, copper diffusion is formed on the tin plating layer ⑷31 originally formed of tin and containing substantially no other metal, and this layer (a) becomes a tin-copper diffusion layer. In addition, it is not necessary to heat the tin-copper diffusion layer.

In this process, after the next solder resist is applied, the heating time for curing the solder resist 20 is short. It can also be printed by the employee ’s consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs when the solder resist 20 is cured. Hot. In this case, the tin plating layer (a) 31 is a tin-plated layer (a) 31 having steel diffusion, and thus a tin-plated layer (a) 3 i having copper diffusion or a tin-plating layer having copper diffusion ( a) 31 is coated with solder resist 20. This solder resist 20 is preferably a thermosetting resin having a high heat resistance. Although a thermosetting resin such as an epoxy resin, a polyimide, or an amino amino acid can be used, it is also possible to use the same. Use a UV-sensitive solder resist. Such anti-turbidity agent will affect the copper-diffused (or diffusible) tin-plated layer (a) 3i and insulating film formed as described above. This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm). 1212 310966 48 () 766 A7 V. Description of the invention (I3) The adhesiveness is not good. Such a solder resist is, for example, coated on the surface of the bell tin layer ⑷31 by screen printing technology. However, the wiring pattern 3 〇Electric joint and its vicinity, such a solder resist 20 is not coated. The coating thickness of this solder resist 20 is usually 5 to 50 mm, preferably cut to 40 mm Within this range, by applying the solder resist to such a thickness, the wiring patterns can be physically protected, and the electrical insulation between the wiring patterns can be more assured. In this way, after the solder resist is applied, if it is a thermosetting resin In this case, the flux is hardened by heating. Although the heating temperature used to harden this flux varies depending on the type of flux used, it is usually 100 to 180 ° C, preferably 130. To 160t, and the heating time is usually from 180 minutes to 180 minutes, preferably It is 60 minutes to 120 minutes. In addition, in order to prevent the occurrence of gaps in the solder resist, heating may be performed in a step (step cure) in which the heating temperature is increased stepwise. Here, it is performed here. In the case of drying, a vacuum drying method, an infrared drying method, etc. can be used. As described above, the solder resist 20 is sufficiently hardened by the heating during drying, and at the same time, the tin plating layer (a) 31 is also heated, and copper is further processed. Then, when the above solder resist is applied without heat treatment, the heating conditions when the solder resist is hardened may be regarded as a suitable heating condition for the hard solder resist to harden the solder resist. Further, the heat treatment for infiltrating copper diffusion is continuously performed as described above. After the solder resist 20 is applied and hardened, tin plating is applied to the surface of the wiring pattern where the solder resist 20 is not applied in the present invention. The size of this paper is in line with China Standard 1 ^ (CNS) A4 size coffee (viewing public) 13 310966

Μ .------ (Please read the notes on the back before filling this page) Order ·-• Wire-486766 A7 V. Description of the invention (l4) This tin plating (b) 3 3 does not contain The metal component other than tin is different from the above-mentioned tin-plated layer (a) 31 having copper diffusion. The thickness of the tin-plated layer (b) 33 formed in this manner is usually from 0.001 to 0.05 # 111 ', preferably from 0.1 to 0.05 // m, and more preferably from 0.001 to. In the present invention, the tin plating layer (b) 33 formed by such an electroless plating method is described as flash plating. By setting the thickness of the tin-plated layer (b) 33 within the above-mentioned range, it is possible to perform reliable bonding ', and at the same time, there is no occurrence of poor plating and short-circuiting is unlikely to occur. In addition, when the solder resist is an ultraviolet light-sensitive photo solder resist, after applying the solder resist on the surface of the tin plating layer by screen printing technology, temporarily drying it, exposing and developing the pattern of the covered portion and the plated portion, and further developing Heating to improve the adhesion between the tin plating layer and the photoresist. At this time, the heating temperature is usually 100 to 18 (rc, preferably 13 to 16). (:, And the heating time is usually 40 minutes to 120 minutes, preferably 60 minutes to 90 minutes. The tin plating layer (b) 33 is the surface of the above-mentioned copper-plated tin plating layer (a), and is formed on the surface not covered with the solder resist 20. That is, the film-shaped mounting tape for electronic component assembly of the present invention The portion of the wiring pattern that is not coated with solder resist, especially the lead wire portion, is formed on the surface of the wiring pattern 30 formed of copper foil, and a copper-diffused tin plating layer (a) 3l is formed. On the surface of the tin plating layer (a) 31, a tin plating layer (b) 33 which does not substantially contain steel is formed. A tin-plated layer (a) having a steel diffusion formed on one surface of a wiring pattern formed of the above-mentioned steel and Tin plating that does not contain copper (the total thickness of this paper is applicable to the Chinese National Standard (CNS) A4 specification (21Q X 297)) " '' ----- ----14 310966 (Please read first (Notes on the back ^ write this page again) 111111. # · Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economy 486766 Economy Printed by A7 _ B7__ of the Intellectual Property Bureau's Consumer Cooperative Fifth, the description of the invention (15) degrees [(a) + (b)] 'usually the range of return ~ Wai'5, the better is 0.2 to 0.6 Within the range of / zm, more preferably in the range of 〇4 to 〇5 / ζιη. As described above, by using rapid plating to form a thin layer of tin plating layer (b) 33 ', it is possible to substantially completely prevent the Whiskers grow. This tin-plated layer (b) 3 3 is essentially formed of tin. When assembling a component with a gold bump electrode, the tin and gold system form a eutectic compound and bumps. The electrode and the wiring pattern 30 (lead wire) can be firmly and surely bonded. In addition, when the tin plating layer (b) is formed by the rapid plating technique, the tin plating layer with copper diffusion and dispersion due to the solder resist ( a) Strong bonding, and the tin plating layer (a) 31 and the solder resist 20 will be strongly adhered, so that the plating solution will not invade between the solder resist 20 and the tin plating layer (a), and even if the plating solution is temporarily Knowing this, 'Because the surface of the wiring pattern 30 is covered with a tin plating layer (api and the copper is not exposed, it is not Since a 4-pack cell is formed due to the invading plating solution, according to the present invention, the cut-out portion (pitting corrosion) at the time of tin plating does not occur on the conventional film-shaped mounting tape for electronic component assembly 35 In addition, it is difficult to cause lead breakage, etc. By using the rapid electroplating technique to form the tin plating layer (b) 33, the generation of tin whisker crystals can be substantially prevented permanently. At this time, it is different from the tin plating layer (a) 31. It is not necessary to perform a heat treatment on the tin plating layer (b) 33. Since the tin plating layer (a) 31 is formed on the wiring pattern, and steel is diffused on the tin plating layer (a) 31, if For a short time, the use of this tin plating layer (a) 31 can control the growth of whiskers, and even after coating the subsequent solder resist and using rapid plating to form the national standard of tin plating layer (b) 33 ( CNS) A4 size (2K) X 297 male ϋ- ~-15 310966 ^ -------- ^ --------- line (please read the precautions on the back before filling this page) 486766 A7 Printed by Consumer Cooperatives, Bureau of Intellectual Property, Ministry of Economic Affairs V. Invention Description (16) There will be a certain period of time before the film-like loading of electronic parts is carried out The performance with reduced. Therefore, according to the present invention, management of manufacturing steps becomes easy. In addition, although the pure tin plating layer (b) 3 3 can usually be produced by one electroplating process step, in order to form the tin plating layer (b) 33, the electroplating process step can be divided into several times. Therefore, in this case, the tin plating layer (b) 33 becomes a composite of a plurality of tin plating layers. The electroplated layer of the present invention consisting of the tin-plated layer (a) with copper diffusion and the tin-plated layer (b) which does not substantially contain copper, and the conventional tin-plated layer can be used for X-ray refraction. Distinguish between method and AES analysis. For example, when the X-ray refraction intensity of Cu3Sn and Cu6Sn5 in the layer is measured by the X-ray refraction method, the plating layer in the film-like placement ▼ of the electronic component assembly of the present invention is usually 1: 0.3 to 0.5 Within this range, in contrast, the conventional plating layer is in the range of 1: 1 to 15. According to the AES analysis method, it can be confirmed that the vicinity of the surface of the plating layer of the present invention is a pure tin plating layer. In contrast, in the conventional plating layer, the steel system diffuses to the vicinity of the surface. The film-shaped mounting tape for electronic component assembly of the present invention is preferably formed by the above-mentioned method, and is used for electronic component assembly for forming a desired wiring pattern by attaching a copper foil to an insulating film and etching the copper foil. A film-shaped carrier tape is formed with a copper-diffused tin plating layer (a) on substantially the entire wiring pattern, and a hardened body of a solder resist can be formed at a predetermined position other than the terminal portion of the wiring pattern. At the same time, the tin-plated layer (a) with copper diffusion on the terminal part can form a mineral tin layer (b) that does not contain copper, and various modifications can be made within the range that does not impair its characteristics. Paper size is applicable to Zhongguanjia Standard (CNS) A4 size ⑵〇x 297 meals) ----------- 1 ^ ί 1 (Please read the note on the back first? Matters written on this page}% Package Too1111111 «

486766 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of Invention (Π). '' For example, in terms of copper vl, not only copper foil but also copper alloy foil can be used, while tin plating is preferably pure tin plating, but in the range of such tin plating layers, the characteristics are not impaired. Contains other metals. The film-shaped mounting tape for assembling the first electronic component of the present invention is formed with a tin-plated layer (a) having copper diffusion over substantially the entire surface of the wiring pattern as described above (the present invention may be described only as "copper diffusion"). Mineral tin layer ⑷ ") and a tin plating layer (b) which does not substantially contain copper on the surface of the terminal portion of this copper diffusion tin plating layer ((the present invention is sometimes only described as" pure tin plating layer (b) ", However, the second film-shaped mounting tape for electronic component assembly of the present invention has a copper-tin-containing area where the copper content rate gradually decreases from the copper diffusion tin plating layer (a) toward the pure tin plating layer over substantially the entire wiring pattern. This copper-tin-containing area 'contains copper in such a way that the copper concentration gradually decreases toward the pure tin-plated layer (b). This copper-tin-containing area is located in the pure bond tin layer of the electric ore, which is a tin layer that is diffused by copper. (B) The method of transferring copper from the copper diffusion tin plating layer ⑷ to the pure tin plating layer (b) is formed continuously with the pure tin plating layer (b). In this second film-shaped mounting tape for electronic component assembly, The insulating film, adhesive layer, solder resist, and wiring pattern are the same as those shown in the figure! The copper diffusion tin plating layer (&) on this wiring pattern is also the same as that shown in the above-mentioned figure 1. 'Before applying the solder resist, tin plating is performed on the surface of the wiring pattern formed by etching. Former. Although the copper diffusion tin plating layer (a) has almost a tin composition after tin plating, the copper used to form the terminals is diffused to this plating by heating when a solder resist is applied and hardened. On the tin layer (a), and this layer becomes the steel diffusion tin plating layer. The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -----

17 310966 (Please read the notes on the back before filling this page) 486766 A7

• 螬 (Fairy -------- Order -------- (Please read the notes on the back before ^ this page) 18 310966 4〇6766 V. Description of the invention (19) Excavation section At the same time, the occurrence of whiskers can be suppressed. The thickness of the rain a ^, the tin plating layer (b) is the same as the one shown in the figure above! ... 0 · 01 to 05 / " m 'The better is 01 to 0 · 5 / ζ m, more preferably # to 〇 · 3 # m. The thickness of this pure tin plating layer (b) can be set within the range of ^, and the actual bonding can be performed without The occurrence of electroplating 7 can almost completely prevent the occurrence of whiskers, and it is not easy to short-circuit. The film-shaped mounting tape for electronic component assembly of the present invention is as described above, and has a steel diffusion tin plating layer, steel and tin containing Area and pure tin-plated layer (b), and the thickness of each layer can be appropriately swallowed within the above range considering the effect of tritium. The average thickness of the copper-tin-containing area where the steel diffusion degree gradually decreases. , = Is from .01 to 05 ... preferably in the range of .0 ... m, and more preferably in the range of 0.1 to 0.3 / Z m. In the second embodiment of the present invention, the film-like mounting for the assembly of electronic parts In the belt,: Diffusion plating The total degree of the tin layer ⑷, the copper-tin-containing area, and the pure tin plating layer (b) is usually in the range of 0.02 to 〇1, preferably in the range of 0.03, and more preferably in the range of 0.02 to 〇- Within the range, it is more preferably within the target range of 0.4 to al. By forming a tin plated layer, the film-shaped mounting for electronic component assembly at a flnepitch is also reliable. Moreover, by forming such a bond tin layer, the mechanical strength of the wire can be improved, while the occurrence of whiskers can be completely prevented, and the incidence of short circuits can be significantly reduced. [Effects of the Invention] ^ * According to the invention The film for electronic component assembly is large in size. The paper size is applicable to the Chinese National Standard (CNS) A4 specification. 〇χ 297 公 爱 486766 A7 V. Description of the invention (2) It can completely prevent the growth of whiskers from wiring patterns, and simultaneously The bulk electrode and the wiring pattern can be firmly and surely bonded. Furthermore, according to the present invention, the plating solution hardly penetrates between the underside of the solder resist and the tin plating layer (a), and even if the plating solution temporarily penetrates there, the surface of the wiring pattern is a tin plating layer ( a) The covered copper is not exposed, so there is no digging (hole erosion) 35 of tinning in conventional coils, and the film-shaped mounting tape leads for electronic component assembly of the present invention are not easily broken. Off and other phenomena. In the film-shaped mounting tape for assembling electronic parts of the present invention, it is difficult to grow whiskers. In particular, the film-shaped carrier tape for assembling the second electronic component assembly of the present invention that forms a copper-tin-containing region can almost completely prevent the occurrence of a cutout, and can also prevent the occurrence of whiskers permanently. Furthermore, according to the manufacturing method of the present invention, since whiskers do not grow during manufacturing, management of manufacturing steps becomes easy. [Examples] Although the examples of the present invention are shown below and the present invention will be described in further detail, the present invention is not limited by these. Example 1 A wiring pattern made of a copper foil having a thickness of 18 // 111 was formed on a polyurethane film. A tin plating layer having a thickness of 4 μm was formed on the entire wiring pattern of the mounting tape, and heat treatment was performed at 125 t for 60 minutes. Next, the lead portion of this pattern is left and coated with solder resist at 80. It was heated at 0 ° C for 45 minutes and then exposed for 8 seconds. After 40 seconds of development, it was heated at 15 ° C for 60 minutes to completely harden the solder resist. 310966 pages

This paper size applies to China National Standard (CNS) A4 specification (21G x 297 public love) 486766

A7 V. Description of the Invention (η) After the solder resist is hardened in this way, the lead portion exposed to a thickness of 0 2 # m is tin-plated and heat-treated at 120 ° C for 60 minutes. Observation of the obtained film-shaped mounting tape for electronic component assembly using an electron microscope revealed that no cutout was formed in the lead portion. Also, the phenomenon that the plating sneaks under the solder resist is not seen. Furthermore, no whiskers were seen growing in the lead portions thus formed. Example 2 A tin plating layer having a thickness of 0.4 / zm was formed on the entire wiring pattern of the mounting tape formed in the same manner as in Example 1, and heat-treated at 125 t for 60 minutes. Next, 'lead the wiring part of the wiring pattern and apply solder resist, heat it at 80 ° C for 45 minutes, and then expose for 8 seconds, highlight 40 seconds, and then heat it at 150 ° C for 60 minutes to Allow the solder resist to harden completely. After the solder resist is hardened in this way, a tin plating layer is formed on the portion of the lead which is exposed to a thickness of 0.2 // m. Observation of the obtained film-shaped mounting tape for electronic component assembly using an electron microscope revealed that no cutout was formed in the lead portion. There was also no sign that the plating had penetrated under the solder resist. Furthermore, no whisker growth was observed in the lead portions thus formed over a long period of time. Example A tin plated layer with a thickness of 0.2 / zm was formed on the entire wiring pattern of the mounting tape formed in the same manner as in Example 1, and it was heat-treated at 125 ° C for 60 minutes. Secondly, leave the lead portion of this wiring pattern and apply solder resist, heat it at 80 ° C for 45 minutes, and then expose it for 8 seconds and develop it for 40 seconds. (Please read the precautions on the back before filling in this page)

Printed on paper by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. The paper has been printed in accordance with the Chinese National Standard (CNS) A4 specification (21 × χ 297 mm 21 310966). CNS) A4 specification (210 X 297 cm ¥ 22) ίου / υο 5. Description of the invention (22 Heating at 0 ° C for 60 minutes to completely harden the solder resist. After hardening the solder resist in this way, the thickness of 0 4 A m is exposed. Part of the bow I line. * Using an electron microscope to observe the obtained 臈 -shaped mounting tape for assembling electronic parts, as a result, no cutout was formed on the lead portion. No phenomenon of electric money infiltrating the solder resist was observed. After a long period of time, no whisker grows in the lead portion thus formed. Example 4 The entire wiring pattern of the mounting tape formed in the same manner as in Example 1 is formed with a tin plating layer having a thickness of · 2 # m. Secondly, the lead of this wiring pattern was left one-knife and coated with an anti-knowledge agent, and heated at 80 ° C for a minute, and then exposed for 8 minutes, and after developing for 40 seconds, it was heated at 15 ° C for 60 minutes. So that the solder resist is finished After hardening, the solder resist is hardened in this manner, and then the exposed lead portion having a thickness of 0.4 m is tin-plated, and then heat-treated at 125 t for 60 seconds. The obtained film-shaped mounting tape for electronic component assembly was observed using an electron microscope. As a result, no cutout was formed on the lead portion. The phenomenon of plating infiltrating under the solder resist was not seen. Furthermore, 'whisker whiskers were not seen growing in the lead portion thus formed. Examples 5 to 1 〇 On the entire wiring pattern of the mounting tape formed in the same manner as in Example 1, a tin plating layer (a) having a thickness described in Table 1 was formed under the conditions described in ^, 310966

486766 A7 5. Description of the invention (23) and heat treatment at 125C for 60 minutes. Next, as in Example 1, the lead portion of this wiring pattern was left, and a solder resist was applied and hardened. After the solder resist is hardened in this way, a tin plating layer (b) is formed on the exposed lead portion. After the tin-plated layer (b) was formed in this manner, the total thickness of the tin-plated layer (a) and the tin-plated layer (b) was measured using fluorescent X-rays, and the results are shown in Table 1. Using an electron microscope to observe the obtained film-shaped mounting tape for assembling electronic parts, no whisker growth was observed. Nor did the plating sneak into the underside of the solder resist. [Table 1] Loading --- (Please read the precautions on the back before filling this page) Order.

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. Table 1 Plating, layer Plating layer thickness Plating time Plating temperature Plating layer (a) Electric money layer [(a) + (b) l (sec) (° C) m) ( Am) Example 5 1 30 0.023 0.542 ~ Example 6 3 30 0.033 0.525 Example 7 1 45 0.041 0.543 ~ Fly Example 8 3 45 0.044 0.543 Example 9 1 70 0.040 0.581 — Example 10 3 70 0.043 0.598 • Wire . Form a wiring pattern made of steel foil with a thickness of 18 // m on a polyurethane film. A tin plating layer having a thickness is formed on the entire wiring pattern on which f is placed. Secondly, the lead portion of the wiring pattern is left and a solder resist is coated thereon, and heated at 80 ° C for 45 minutes, and then exposed for 8 seconds. After 40 seconds of development ', heating at 150 ° C for 60 minutes to completely harden the solder resist. “The tensile scale is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm 310966 486766 A7. Employee Consumer Cooperatives, Intellectual Property Bureau, Ministry of Economic Affairs) Printed Γ-21 --- 5. Description of the invention (24) In the dry heat curing process, copper in the wiring pattern will diffuse onto this tin plating layer to form a copper diffusion tin plating layer (a). After the solder is hardened, a 0- 4 # m-thick tin plating layer is formed on the wire portion, and a portion of the copper in the steel diffusion tin plating layer (a) and the copper in the wiring pattern are moved to the heat by making it heat sensitive. The thickness of the pure tin-plated layer in the film-shaped carrier tape for this electronic component assembly is 〇21 # m on the tin-plated layer thus formed to form a copper-tin-containing area having a thickness of 0.19 // m. 〇Steel diffusion in the film-shaped carrier tape for electronic component assembly The total thickness of the tin layer (a), the copper-tin-containing area, and the pure tin-plated layer (1)) is 044 / zm. The total thickness of the tin-plated layer of the present invention is measured using a fluorescent X-ray film thickness. Device for determination. Observation of the obtained film-shaped mounting tape for electronic component assembly using an electron microscope revealed that no cutout was formed in the lead portion. Nor did the plating sink into the solder mask. It is also not seen that whiskers grow in the lead portions thus formed. The thickness of the pure tin-plated layer measured with a Kegel film thickness measuring device was 0.21 # m, and the steel diffusion tin-plated layer (a) and steel-tin-containing areas measured with a fluorescent x-ray film thickness measuring device The total thickness of the pure tin plating layer (b) is 0 material / m ', and the thickness of the above-mentioned copper diffusion tin plating layer is 〇44 ", so the thickness of the copper-tin-containing diffusion region is 019 mm. ^. In addition, this Kogel thickness measurement device is based on the electrolytic solution dripping on the predetermined surface of the tin plating layer to perform electrolysis. When the potential rises, it will stop. This paper scale applies the Chinese National Standard (CNS) A4 standard. (2ig χ 297 public love) ---__ 24 310966 Please read first-Note on the back! Matter | Item 1

Order I

A7 V. Description of the invention (25) Electrolytic action, and push you from the current of each order and the area of the mother's area at this time: install: from the measured area and the tin-tin layer: the degree is obtained as above 4 ^ „^ The pancreas-shaped mounting belt for clothing does not dig, and crystals are not used for the assembly of electronic components. No need to occur on the belt-shaped mounting belt [Simplified description of the drawing] Section 1 Fig. 2 is a cross-sectional view showing an example of a cross section of a bow I-line portion in a film-shaped mounting tape for electronic component assembly of the present invention. Sectional view. Figure 3 is an explanatory diagram of the mechanism with a cutout. [Element number description] 10 Insulation 臈 12 Adhesive layer 20 Solder resist 30 Wiring pattern (copper box) 31 Tin-plated layer with steel diffusion (a ) (Copper diffusion tin plating (a)) 32 Tin plating that does not substantially contain steel (b) (Pure tin plating (b)) (Please read the precautions on the back before filling this page) Intellectual Property of the Ministry of Economic Affairs Bureau of the Consumer Cooperatives printed this paper standard applicable _ house standard (CNS) A4 specifications (21Q χ 297 public love) 25 310966

Claims (1)

public I amended '·,' ,,, and No. 88119626 Patent Application Amendment (December 13, 1990) — a film-shaped mounting tape for electronic component assembly, which is attached to an insulating film to occupy a copper box. And etching the copper pig to form a desired wiring pattern; characterized in that tin plating is performed on substantially the entire wiring pattern to form a copper-diffused tin-plated layer (a) 'the average thickness of the tin-plated layer (a) It is within the range of 001 to 005; and a protective layer made of a hardened body of a solder resist is formed at a predetermined position other than the terminal portion of the wiring pattern, and at the same time there is copper diffusion in the terminal portion A tin-plated layer (b) containing substantially no copper is formed on the surface of the tin-plated layer (a), and the average thickness of the tin-plated layer (13) is in the range of 0.001 to 0.5 / zm. Ί For example, the 貘 -shaped mounting tape for assembling electronic parts according to item 1 of the patent scope, wherein the tin-plated layer (a) with copper diffusion formed on the surface of the wiring pattern formed of the above copper and substantially no copper The total thickness of the tinned layer (b) is in the range of 0.02 to 0.6 m. D. Baker Welfare Committee of the Central Standards Bureau of the Ministry of Economic Affairs: BEI will print film-shaped carrier tapes for assembling electronic components. Those who stick a steel foil on an insulating film and etch the copper foil to form a desired wiring pattern; It is characterized in that the entire wiring pattern is plated with tin to form a copper-diffused coin tin layer (a), and a hardened body made of a solder resist is formed at a predetermined position other than the terminal portion of the wiring pattern. The protective layer also has a tin-plated layer (a) having copper diffusion on the terminal portion and a copper-diffusion layer (a) having a copper diffusion concentration from the surface of the steel-plated bell tin layer (a) facing the tin-plated layer (b) not substantially containing copper. Steel and tin containing areas with gradually decreasing surface, and this area and the tin-plated layer that does not actually contain copper (b) are successively shaped gems; Genb ibf Ι3Π on rPr / ^ T ^. \. \ ^ 7 ^, ^.. ^ 7 ^ v 1 310966, the average thickness of the tin plated layer ⑷ is within the range of to, and the average thickness of the tin plated layer 系 is within the range of 0.001 to 0.05. 4. The film-shaped mounting tape for electronic component assembly as described in the scope of patent application No. 3, in which a copper-diffused mineral tin layer formed on the surface of a wiring pattern formed of the above-mentioned steel, steel, tin-containing areas, and solid f The total thickness of the copper-tin-free tin layer (b) is in the range of G.G2 to G " m. A method for manufacturing a film-shaped carrier tape for assembling electronic parts, characterized in that a copper foil is adhered to an insulating film, and the steel foil is etched to form a desired wiring pattern, and the entire wiring pattern is formed After the tin-plated layer 平均 having an average thickness of copper diffusion in the range of 0.01 to 0.5 / zm, a solder resist is applied and hardened at a predetermined position other than the terminal portion of the wiring pattern, and when the solder resist After hardening, tin plating is performed again on the terminal portion of the wiring pattern to form a tin layer (b) having an average thickness that does not substantially contain copper in the range of 0.01 to G.5 # m. Before soldering, the wiring pattern is heated at 80 to 50 ° :. 6 'The method of manufacturing a film-shaped carrier tape for assembling electronic parts according to item 5 of the patent application, wherein a tin-plated layer (a) having a steel diffusion formed on a surface of a wiring pattern formed of the above-mentioned steel is formed. The total thickness of the tin-plated layer (b) which does not substantially contain steel is in the range of 0.02 to 0'6 # m. 7. · A method for manufacturing a film-shaped carrier tape for assembling electronic parts, comprising attaching a copper foil to an insulating film and etching the copper foil to form a desired wiring pattern. Tin plated, and coated with paper on a predetermined portion other than the terminal portion of the wiring pattern; applicable to China National Standards (CNS) A4 specification (21〇χ 297 public) 2 310966 ΓΓ agent and make the child mine tin again Step, characterized in that: the sub-section ± is formed with a bell tin layer 钢 having an average thickness of steel diffusion within a range of r: m, and heating the wiring pattern 2 coated with anti-tanning agent 80 to 150t; and copper The surface of the ore tin layer that is scattered loosely does not substantially contain steel = 2: The surface of the ore tin layer in the range of 01 to ° · 5 ° (b) gradually decreases to 2 copper and tin containing areas, and this area is related to In fact does not contain = mirror tin layer (b) continuous formation. 8. The above-mentioned copper diffusion concentrations in the film-shaped mounting tapes for electronic component assembly of item ΠΠ, Γ7 are gradually reduced, and the average thickness is ′. ·. … .5… Scope: The t-two method of the film-shaped carrier tape for rabbit parts for electronic parts with the scope of patent No. 7, wherein a copper-diffusion bell tin layer formed on the surface of the wiring pattern formed by the copper The total thickness of the tin plating sound (b) which does not substantially contain steel is in the range of G.G2 to 0.6 center. Printed by the Staff Welfare Committee of the Central Bureau of Standards of the Ministry of Economic Affairs 10. Method for making k-shaped mounting tapes for assembling electronic parts such as in the scope of patent application No. 7 'Method in which the above-mentioned copper diffusion concentration gradually decreases in the steel containing tin area The copper concentration is lower than the average steel concentration in the tin ore layer with copper diffusion. 310966