JPH0485944A - Film carrier tape and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a satisfactory contact condition by a method wherein a plating layer on the one of the surfaces of a lead and a plating layer on the other surface are made of same type of metal and their respective thicknesses are different from each other. CONSTITUTION:After a Cu layer 12 is formed on a base film 11, a resist film 13a which has patterns of leads and the like is provided. After Cu is selectively deposited on the Cu layer 12 by an electrolytic plating method to form the leads 14, Au plating is applied to form an Au plating layer 15a. Then a resist film 13b which has patterns of a device hole, an OLB hole, sprocket holes, etc., is provided on the upper surface of the base film 11 and the base film 11 is etched to form the sprocket holes 16a, the OLB hole 16b, the device hole 16c, etc. After the resist films 13a and 13b are removed, Cu is etched as a whole and Au plating is applied to the leads 14 to form Au plating layers 15b. With this constitution, a semiconductor chip can be bonded to the leads and the pad of a substrate can be bonded to the leads under satisfactory conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a film carrier tape that constitutes a film carrier semiconductor device by bonding semiconductor chips to its leads, and a method for manufacturing the same.

[Prior Art] Fig. 4 is a plan view showing a conventional film carrier tape;
FIG. 5 is also a sectional view thereof.

The base film 1 is a band-shaped insulating film made of polyimide or the like, and sprocket holes 2 for conveyance and positioning are provided at regular intervals on both side edges thereof. Further, in the widthwise central portion of the base film 1, rectangular device holes 3 are provided at a predetermined pitch in the longitudinal direction of the base film 1. A beam 4 is arranged around each device hole 3. The adhesive 4 is, for example, made by bonding a metal foil such as copper onto the base film 1 and selectively etching this metal foil into a predetermined shape using a photoresist method or the like. The end of the lead 4 on the device hole 3 side extends into the device hole 3, and the other end of the lead 4 has an electrical selection pad 5 formed at the same time as the lead 4.

A suspender 6, which is a frame of an insulating film, is provided around the device hole 3, and a LB hole (outer lead bonding hole) 3a is provided outside the suspender 6.

The lead 4, whose tip end protrudes into the device hole 3, is prevented from being deformed by having its middle part supported by suspenders 6.

Next, an example of a conventional method for manufacturing a film carrier tape will be described.

First, a Cu layer is formed on a base film 1 made of polyimide or the like by electroless plating or vapor deposition. Next, a resist film is formed in a predetermined pattern on this Cu layer by a photoresist method, and then Cu is selectively deposited on the Cu layer on which the resist film is not adhered by an electrolytic plating method. Leads 4 and pads 5 are formed. Thereafter, the base film 1 is selectively etched using a photoresist method to form device holes 3, OLB holes 3a, sprocket holes 2, etc. Next, after removing the resist film, the entire Cu layer is etched to remove the Cu layer remaining between the leads 4 and the like. and,
Apply predetermined plating to lead 4, etc. This completes the film carrier tape.

Next, a method for manufacturing a film carrier semiconductor device using a film carrier tape will be described.

A semiconductor chip 7 is placed in the center of the device hole 3 of the film carrier tape. Bumps 7a, which are metal protrusions, are formed on the electrode terminals of this semiconductor chip 7. Then, the bump 7a and the lead 4 are connected by inner lead bonding (hereinafter referred to as ``LB'') using a thermocompression bonding method or a eutectic method.

In this way, after placing the semiconductor chip 7 in the device hole 3 and fixing the semiconductor chip 7 to the film carrier tape via the leads 4 and bumps 7a, as shown in FIG. , liquid resin 8a is dropped by a so-called potting method. Then, by curing the resin 8a, the surface of the semiconductor chip 8a is sealed with the resin.

Thereafter, with the semiconductor chip 7 mounted on the film carrier tape, an electrical selection test and a bias test are performed on the semiconductor chip 7 by bringing a contact into contact with the electrical selection pad 5 to remove defective products. (Thus, the film carrier semiconductor device is completed.

This film carrier semiconductor device is mounted on a printed circuit board 10 as shown in FIG.

That is, first, the leads 4 are cut to a desired length and the semiconductor chip 7 is separated from the film carrier tape. Then, this semiconductor chip 7 is fixed onto the printed circuit board 10 with an adhesive 8b. Next, connect the leads 4 to the printed circuit board 1.
Outer lead bonding (hereinafter referred to as OLB) is performed to the bonding pad 9 on the 0. This completes the mounting of the film carrier semiconductor device onto the printed circuit board 10.

A film carrier semiconductor device using a film carrier tape has a large number of bumps 7a and leads 4.
Since all the bumps 7a and leads 4 can be bonded at the same time, there is an advantage that the time required for ILB is short, and since a film carrier tape is used, there are also advantages such as easy automation of the work. There is.

By the way, the film carrier semiconductor device is made of Au-Au.
It is mounted on a printed circuit board by thermocompression bonding, Au-8n eutectic method, brazing using conductive adhesive and solder, etc. Further, components such as semiconductor devices in which a resistor, a capacitor, and a semiconductor chip are sealed in a plastic package or a ceramic package are generally mounted on a printed circuit board by brazing using solder.

In this case, first, solder paste is applied onto the bonding pads of the printed circuit board using a printing method, and then components such as semiconductor devices and resistors are bonded to predetermined positions on the printed circuit board using an adhesive. Then, the printed circuit board is inserted into an infrared heating furnace, a hot air heating furnace, a heated steam tank, etc., the solder paste is melted, and components such as semiconductor devices and resistors are mounted on the printed circuit board. Mounting using such a solder reflow method has advantages such as being able to mount many components at the same time and improving work efficiency.

However, in the case of a film carrier semiconductor device, when mounting is performed by the solder reflow method, as described above, since the suspenders 6 are formed of an insulating film, the suspenders 6 are deformed due to the heat during mounting. , office lady
Variations occur in the height of the lead tips on the B side. Therefore, when mounting a film carrier semiconductor device using the solder reflow method, it is necessary to press the lead tips toward the printed circuit board during mounting. Therefore, mounting of a film carrier semiconductor device is generally carried out by pressing a heating tool against the leads.

In addition, since general printed circuit boards are mainly composed of resins such as glass epoxy or glass phenol, their heat resistance is relatively low.
Implementation using the U-8N common product method is not suitable. For this reason,
When components such as semiconductor devices are mounted on a printed circuit board whose main component is a resin such as glass epoxy or glass phenol, they are often connected using a conductive adhesive or solder.

Although conductive adhesives are widely used in OLBs of film carrier semiconductor devices, they have the disadvantage of high connection electrical resistance, which limits the types of semiconductor devices that can be used.

For example, mounting with a conductive adhesive is not suitable for semiconductor devices that operate at high speed, such as memories, microcomputers, and gate arrays.

These semiconductor devices are preferably mounted using solder.

By the way, in the case of a film carrier semiconductor device, the leads are plated with metal such as Au1Sn or solder.

Leads plated with Sn or solder are suitable when a semiconductor device is mounted by soldering. However, Sn-plated leads have the disadvantage that Sn whiskers are likely to occur.

On the other hand, solder-plated leads have connection parts (
The solder in the solder plating layer near the bonding part will melt,
There is a risk that this solder will concentrate at the connection portion and form solder balls, which will connect the leads and the semiconductor chip. Therefore, in order to avoid such a situation, it is necessary to manage the plating conditions so that the thickness of the solder plating layer is as thin as about 1 μm, and also to appropriately manage the ILB conditions. However, even if the thickness of the solder plating layer is controlled in this manner, OLB cannot be performed stably during OLB because the thickness of the solder plating layer is as thin as about 1 μm.

Further, when the leads are plated with Au, the leads and the semiconductor chip can be easily and stably bonded. However, when the Au plating layer is thick, during OLB using solder, an intermetallic compound is generated by diffusion of Au, Sn, etc. at the connection interface between the Au plating layer and the solder, and the connection strength is significantly reduced. For example, about 2.
When a lead plated with Au with a thickness exceeding 0 μm is connected to a printed circuit board by soldering, the connection part initially has a thickness of 50 μm.
It has sufficient strength from 100 g to 100 g or more. However, the semiconductor device connected to this printed circuit board,
When an accelerated test is performed for 200 to 300 hours at a temperature of 150° C., the strength of the connection portion deteriorates to 10 g or less.

This deterioration in the strength of the connection portion is caused by intermetallic compounds generated in the connection portion, and is accelerated as the amount of Au increases. Therefore, conventionally, film carrier tapes for film carrier semiconductor devices mounted by solder are made of Au.
Manufactured by controlling the thickness of the plating layer. In this case, it is known that the upper limit of the proportion of Au to the solder in the connection portion is preferably about 2% by weight.

[Problems to be Solved by the Invention] However, conventional film carrier tapes have the following problems.

That is, in recent years, there has been a remarkable tendency for semiconductor devices including film carrier semiconductor devices to have a large number of pins, and as a result, the lead pitch has become narrower, such as 0.5 mm or less. Therefore, the connection area between the leads and the board is reduced, and the OL
At time B, the amount of solder may not be sufficient for the Au plated on the lead. It may be possible to adjust the ratio of Au and solder in the connection part by reducing the thickness of the Au plating layer on the lead, but it is possible to obtain a stable connection between the semiconductor chip and the lead in the ILB, and to reduce the thickness of the Au plating layer on the lead.
In order to ensure the initial strength of the connection part in LB, there is a limit to the reduction in plating thickness.

In other words, in the film carrier semiconductor device, it is preferable that an Au plating layer be formed on the ILB side portion of the lead to a thickness of a certain value or more, or a solder plating layer be formed to a thickness of a certain value or less. , while the lead O
It is preferable that an Au plating layer is formed on the LB side portion with a thickness of a certain value or less, or a solder plating layer is formed with a thickness of a certain value or more. In other words, by partially changing the lead thickness of the film carrier tape,
It is preferable to partially plate different metals with two or more metals.

In the case of semiconductor devices in plastic packages, the leads may be partially plated by mechanical masking. However, in the case of film carrier tape, - for boat fishing, the lead is made of Cu with a thickness of about 35 μm and a width of about 100 μm, and its mechanical strength is relatively low and lead deformation easily occurs, so mechanical masking is required. It is difficult to make the plating thickness different between the ILB side and OLB side of the lead by partial plating using. It is also possible to perform partial plating or different plating while protecting the leads by repeating masking using a photoresist method, but this would increase and complicate the manufacturing process, making the manufacturing of the film carrier tape extremely complicated. become.

The present invention has been made in view of such problems, and includes:
It is an object of the present invention to provide a film carrier tape that is easy to manufacture, can perform ILB and OLB using solder reliably even when the lead pitch is small, and has high reliability, and a method for manufacturing the same.

[Means for Solving the Problems] The film carrier tape according to the present invention includes a base film provided with sprocket holes and device holes, and a base film provided on one side of the base film extending to the device holes, and both sides of the base film. The lead is plated with metal, and the plating layer on one side and the plating layer on the other side of the lead are made of the same kind of metal and have different thicknesses.

The first method for manufacturing a film carrier tape according to the present invention includes the steps of: forming a metal layer on an insulating base film; providing a resist film having openings in a predetermined pattern on the metal layer; forming a lead by depositing metal in the predetermined pattern on the metal layer using the resist film as a mask; forming a first plating layer on the lead using the resist film as a mask;
The method is characterized by comprising a step of removing the resist film, a step of providing a device hole in the base film, and a step of plating the lead to form a second plating layer.

In addition, the second method for manufacturing a film carrier tape according to the present invention includes a step of providing a device hole in an insulating base film, a step of bonding a metal foil onto this base film, and a resist on both sides of the base film. a step of forming the resist film on the metal foil into a predetermined pattern; a step of etching the metal foil using the resist film as a mask to obtain a lead; a step of removing the resist film; a step of plating the lead to form a first plating layer; a step of removing the remaining resist film; and a step of plating the lead to form a second plating layer. The method is characterized in that the step of forming a plating layer is performed overnight.

[Operations] In the present invention, the thicknesses of the plating layers formed on both sides of the lead are different from each other. For example, if the plating metal is Au, the leads can be bonded to the semiconductor chip on one side where the Au plating layer is thick, and the leads can be bonded to the printed circuit board on the other side where the plating layer is thin. By bonding to rLB and OLB, it is possible to connect with both rLB and OLB in a good bonding state. For example, if the plated metal is solder, connect the leads to the printed circuit board on one side with a thick solder plating layer, and connect the leads to the semiconductor chip on the other side with a thin solder plating layer. By connecting them, it is possible to obtain a good connection state with both the ILB and OLB.

The preferred plating thickness for ILB and OLB differs depending on the lead pitch, bonding size of the printed circuit board, etc. When the plating metal plated on the lead is Au, the plating thickness on the ILB side surface needs to be thicker than the plating thickness on the OLB side surface. In order to connect the leads and the semiconductor chip in good condition, the ILB
It is preferable that the Au plating thickness on the side surface is 0.2 μm or more. Also, the Au plating thickness on the OLB side surface is 2.
If it exceeds 0 μm, an intermetallic compound between the solder and Au will be generated during OLB and the strength of the connection will decrease.
The plating thickness on the B side surface is preferably 2.0 μm or less.

Similarly, if the plating metal plated on the lead is solder, the plating thickness on the ILB side surface needs to be thinner than the plating thickness on the OLB side surface. In order to bond the leads and the semiconductor chip in good condition,
It is preferable that the solder plating thickness on the ILB side surface is 3.0 μm or less.

Further, the solder plating thickness on the OLB side surface is preferably 2.0 μm or more in order to perform OLE with a good bonding state.

Further, in the first manufacturing method of the present invention, leads are formed in a predetermined pattern on a base film using a resist film, and then a first plating layer is formed on the leads using the resist film. form. After a device hole or the like is provided in the base film to expose the back surface of the lead, the lead is plated to form a second plating layer. As a result, two plating layers are provided on the top surface of the lead, and one plating layer is provided on the bottom surface of the lead, making it possible to obtain a lead in which the thickness of the plating layer differs between the front and back surfaces. In this case, since the first plating layer uses the resist film used when forming the leads as is, an increase in the number of manufacturing steps can be suppressed.

Furthermore, in the second manufacturing method of the present invention, first, device holes and the like are provided in a base film, and then a metal foil is bonded onto this base film.

A resist film is applied to both sides of the base film,
After patterning the resist film on the metal foil,
Using this resist film as a mask, the metal foil is etched to obtain leads. Next, the resist film on the lead is removed, and the lead is plated to form a first plating layer. Next, after completely removing the remaining resist, the leads are plated to form a second plating layer. This makes it possible to obtain a lead in which the thickness of the plating layer differs between the front and back surfaces.

[Embodiments] Next, embodiments of the present invention will be described with reference to the accompanying drawings.

FIGS. 1(a) to 1(d) are cross-sectional views showing a method for manufacturing a film carrier tape according to a first embodiment of the present invention in order of steps.

First, as shown in FIG. 1(a), a base film 1 made of polyimide or the like is formed by electroless plating or vapor deposition.
A Cu layer 12 is formed on top of the Cu layer 12.

Next, as shown in FIG. 1(b), a resist M 13 a in which a pattern such as a lead is opened is provided on the 00 layer 12 by a photoresist method. Then, Cu is selectively deposited on the 00 layer 12 by electrolytic plating to form the leads 14. After that, Au is placed on this lead 14.
is plated to form a first Au plating layer 15a.

Next, a device hole is formed on the upper surface of the base film 11.
Resist j with patterns such as LB holes and sprocket holes opened! 13b! Let's go.

Next, as shown in FIG. 1(C), the resist film 13b is
- Apply anti-etching to the base film 11 as a mask, and sprocket holes 16a10LB holes 16b
A device hole 16c and the like are formed.

Next, as shown in FIG. 1(d), the resist film 13a,
After removing 13b, the entire Cu is etched.

As a result, portions of the Cu layer 12 that are not in contact with the base film 11 are removed.

Thereafter, the lead 14 is plated with Au by electrolytic plating to form a second Au plating layer 15b.

In the film carrier tape manufactured in this way, two Au plating layers 15a and 15b are provided on the upper surface of the lead 14, and one Au plating layer 15b is provided on the lower surface of the lead 14. Therefore, the Au plating layer on the top surface of the lead 14 is thicker than the Au plating layer on the bottom surface. Furthermore, in this embodiment, the first Au plating layer 15a is selectively formed on the leads 14 using the resist film 13a used to form the leads 14.
Compared to conventional manufacturing methods, the number of manufacturing steps increases less.

Furthermore, since Au plating is performed with the leads 14 fixed on the base film 11, deformation of the leads during the plating process can be suppressed. Furthermore, the method of this embodiment can be applied to film carrier tapes that are not provided with suspenders, unlike conventional partial thickness plating and dissimilar plating.

FIG. 2 is a sectional view showing a method for mounting a semiconductor device using the film carrier tape of this example.

First, one surface of the lead 14 having two Au plating layers is brought into contact with the bump 7a of the semiconductor chip 7, and the IJ-)' 14 and the semiconductor chip 7 are bonded together by thermocompression bonding, eutectic method, etc.
to join. Then, the surface of the semiconductor chip 7 on which the bumps 7a are formed, including this joint portion, is sealed with a resin 8a. Next, each lead 14 is cut at the outer edge side of the OLB hole 16b,
The other surface of the IJ-)' 14 having one Au plating layer is brought into contact with the pad 9 of the printed circuit board 10, and the lead 14 and the pad 9 are joined by, for example, solder.

In this case, the bonding between the leads 14 and the semiconductor chip 7 is as follows:
Since two Au plating layers are provided and the process is performed on the side having a relatively thick Au plating layer, LB can be performed in good condition. Further, since the thickness of the Au plating layer on the OLB side surface is relatively thin, an intermetallic compound between Au and solder is not generated in the OLB, and OLB can be performed in a good condition.

In addition, in order to perform ILB in a good bonding state, ILB
The total thickness of the Au plating layer on the side surface is 0.2 μm or more, preferably 0.5 μm or more. Further, the appropriate thickness of the Au plating layer on the OLB side surface varies depending on the size of the bonding pad of the printed circuit board and the amount of solder supplied to the joint during OLB.

However, in order to perform OLB in a good bonding state, OLB
The thickness of the Au plating layer on the side surface is 2.0 μm or less, more preferably 0.5 μm or less.

Moreover, although the above-mentioned embodiment is a case where the leads are plated with Au, the metal to be plated on the leads is not limited to this, and may be solder, for example.

When plating solder on the leads, make sure the joint is in good condition.
In order to perform LB and OLE, the plating thickness on the ILB side surface is thinner than the plating thickness on the OLB side surface, and
The thickness of the solder plating layer on the B side surface is 3.0 μm or less,
The thickness of the solder plating layer on the OLB side surface is controlled to be 2.0 μm or more.

FIGS. 3(a) to 3(e) are cross-sectional views showing, in order of steps, a method for manufacturing a form carrier tape according to a second embodiment of the present invention.

First, as shown in FIG. 3(a), a sprocket hole 26a is formed in the base film 21 coated with the tape adhesive 22 by a northing process or the like.

An OLB hole 26b, a device hole 26c, etc. are formed. After that, Cu foil 24 is placed on this base film 21.
Glue a.

Next, on both sides of the base film 21, a resist film 23a,
Apply 23b. That is, the resist film 23a is applied on the Cu foil 24a, and the sprocket holes 26a,
OLB hole/l/ 26 b and device hole 26c
A resist film 23b is applied so as to embed it.

Next, as shown in FIG. 3(C), the resist film 23a is opened in a predetermined pattern by a photoresist method, and
Leads 24 and the like are formed by selectively etching the U foil 24a.

Next, as shown in FIG. 3(d), only the resist film 23a on the side where the leads 24 are formed is selectively removed. For this purpose, for example, the resist film 2 on the side where the leads 24 are formed is
3a and the resist film 2 buried in the device hole 260, etc.
3b is formed with a different type of resist, and the resist film 2
3a is removed using a suitable solvent or the like. Thereby, only the resist film 23a can be selectively removed. next,
Au plating is performed to form a first Au plating layer 25a on the lead 24.

Next, as shown in FIG. 3(e), the resist film 23b is
remove. After that, Au plating is performed, and a second Au plating is applied to the part of the glue 24 that is not in contact with the base film 21.
A u plating layer 25b is deposited.

In the carrier film tapes manufactured in this way, the thicknesses of the Au plating layers formed on both sides of the leads 24 are different from each other. Therefore, as explained in the first embodiment, if the leads and the semiconductor chip are bonded on the surface where the total thickness of the Au plating layer is thick, ILB can be performed in a good bonding state, and the thickness of the Au plating layer If OLE is performed using solder on a thin surface, the formation of intermetallic compounds between Au and solder can be suppressed, and a good bonding state can be obtained.

Note that in this embodiment as well, the leads may be plated with solder instead of Au, as described in the first embodiment.

Further, in this embodiment, the resist film 23a on the upper surface of the lead 24 was removed before the resist film 23b filled with the device hole 26 etc., but after the process shown in FIG. 3(b), the resist film 23b was removed. may be removed, the leads 24 may be plated with Au from the device hole 26 side, and then the resist film 23 may be removed and Au plating may be performed again.

This makes it possible to manufacture a film carrier tape in which the Au plating layer on the upper surface of the lead 24 is thinner than the Au plating layer on the lower surface.

Furthermore, before forming the Au plating layer 25a, the surface of the lead 24 may be plated with Ni as base plating.

[Effects of the Invention] As explained above, according to the present invention, since the thickness of the plating applied to the lead is different on both sides of the lead, ILB and OLB can be performed on separate lead surfaces. Accordingly, both the semiconductor chip and the leads and the pads of the substrate and the leads can be bonded in good condition.

Further, according to the method of the present invention, plating is performed with a resist film adhered to one surface of the lead to form a first plating layer on the other surface, and then the resist film is removed and plating is performed. Since the second plating layer is formed on the leads, the film carrier tape having the above-described structure can be easily manufactured.

[Brief explanation of drawings]

FIGS. 1(a) to (d) are cross-sectional views showing the manufacturing method of a film carrier tape according to the first embodiment of the present invention in the order of steps, and FIG. 2 is a mounting of a semiconductor device using the same film carrier tape. Cross-sectional view showing the method, Figure 3(a)
7(e) are cross-sectional views showing the manufacturing method of a form carrier tape according to the second embodiment of the present invention in order of steps, FIG. 4 is a plan view showing a conventional film carrier tape, and FIG. 5 is a cross-sectional view thereof. FIG. 6 is a sectional view showing a semiconductor device using the same film carrier tape, and FIG. 7 is a sectional view showing a method of mounting a semiconductor device using the same film carrier tape. 1.11, 21; Base film, 2 lI Ei a
+26a; Sprocket hole, 3, 16 C, 26
C; Device hole, 3a, 18b, 26b; OLB hole, 4, 14, 24; Lead, 5; Pad, 6; Suspender 7; Semiconductor chip, 7a; Bump, 8a;
Resin, 8b; Adhesive, 9: Bonding pad, 10;
Printed circuit board, 12; Cu layer, 13a, 13b, 23a
+ 23b; resist film, 15a + 15b, 25a
, 25b; Au plating layer, 22; tape adhesive

Claims (5)

[Claims] (1) A base film provided with a sprocket hole and a device hole, and a lead provided on one side of the base film to extend into the device hole and metal plated on both sides, and the lead A film carrier tape characterized in that the plating layer on one side and the plating layer on the other side are made of the same kind of metal and have different thicknesses. (2) The metal plated on the lead is Au, and the thickness of the plating layer on one side of the lead is 0.2 μm.
As described above, the thickness of the plating layer on the other side of the lead is thinner than the thickness of the plating layer on the one side, and 2.
The film carrier tape according to claim 1, wherein the film carrier tape has a thickness of 0 μm or less. (3) The metal plated on the lead is solder, and the thickness of the plating layer on one side of the lead is 2.0 μm.
3. The thickness of the plating layer on the other side of the lead is thinner than the thickness of the plating layer on the one side.
The film carrier tape according to claim 1, wherein the film carrier tape has a thickness of 0 μm or less. (4) A step of forming a metal layer on an insulating base film, a step of providing a resist film having openings in a predetermined pattern on this metal layer, and a step of forming a metal layer on the metal layer using this resist film as a mask. forming a lead by depositing metal in a predetermined pattern; forming a first plating layer on the lead using the resist film as a mask; removing the resist film; A method for producing a film carrier tape, comprising the steps of providing a device hole and plating the leads to form a second plating layer. (5) A step of providing a device hole in an insulating base film, a step of bonding a metal foil onto this base film, a step of covering both sides of the base film with a resist film, and a step of forming a device hole on the metal foil. a step of forming a resist film into a predetermined pattern; a step of etching the metal foil using the resist film as a mask to obtain a lead; a step of removing the resist film on the lead; and a step of plating the lead. a step of plating the leads to form a first plating layer; a step of removing the remaining resist film; and a step of plating the leads to form a second plating layer. Method for manufacturing film carrier tape.