JPH03255641A - Film carrier tape - Google Patents

Abstract

PURPOSE:To prevent completely the deformation of leads as well as to widen the intervals between outer lead bondings(OLBs) to prevent the generation of a shortcircuit by a method wherein pads for OLB use are provided on the rear of a film carrier tape instead of outer lead bonding(OLB) leads. CONSTITUTION:A film carrier tape 6b is provided with sprocket holes 1b, a device hole 3b and leads 4. A semiconductor chip 2b is bonded to the leads 4b via bumps 7b provided on electrode terminals and the leads 4b are connected to OLB pads 14b on the rear of the tape 6b via through hole 13b in the tape 6. The pads 14b are arranged in two rows in a zigzag form and are alternately arranged in such a way as to face each other holding the holes 13b arranged in two rows between them. The pads 14b formed in one row of the two rows are formed between the hole 3b and the hole 13b and are respectively provided at positions, through which lead patterns located on the opposite surface, the tape 6b surface, pass.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a film carrier tape for a film carrier semiconductor device, and particularly to a film carrier tape for multiple leads.

[Conventional technology]

As shown in the plan view of FIG. 7 and the cross-sectional view of FIG. 1, the conventional method of manufacturing a semiconductor device using a film carrier tape includes a sedge rocket hole la for transportation and positioning and an opening into which the semiconductor chip 2a is inserted. The device hole 3a is
A film carrier tape 6a is prepared by bonding a metal foil such as copper on an insulating film such as polyimide having a . In addition, a semiconductor chip 2a in which bumps 7a, which are metal protrusions, are provided on the electrode terminals, is separately prepared, and then the leads 4a of the film carrier tape 6a and the bumps 7a of the semiconductor chip 2a are bonded by thermocompression bonding. The case is completed by inner lead bonding (hereinafter referred to as ILB) L using a eutectic method or the like, and by connecting a contactor on the electrical selection pad 5a in a film carrier tape state and conducting electrical selection and bias testing.

Here, in order to prevent deformation of the lead 4a, suspenders 8a, which are frames of an insulating film, are provided on the film carrier tape in advance, and in order to improve reliability and mechanical protection, a resin 9a is applied as shown in the cross-sectional view of FIG. In some cases, resin sealing is performed by botting.

When mounting the film carrier semiconductor device as described above, the leads 4a are cut to a desired length, and then the 10th lead 4a is cut to a desired length.
As shown in the cross-sectional view of the figure, for example, after fixing the semiconductor chip 2a onto the printed circuit board 11a with an adhesive 10a, the leads 4a are mounted on the bonding pads 12a on the printed circuit board by outer lead bonding (hereinafter referred to as 0LB). There is.

These film carrier semiconductor device manufacturing methods have advantages such as high bonding speed because bonding can be done at once regardless of the number of leads, and easy automation of work because film carrier tape is used. have.

[Problem to be solved by the invention]

The conventional film carrier semiconductor device described above is an OLB.
Since the leads used for this purpose are thin and thin, there is a drawback that lead deformation easily occurs and mounting is difficult.

In particular, semiconductor devices with a large number of leads have narrow lead pitches, so if they are joined by solder, short circuits may occur due to solder bridges, making mounting even more difficult.

It is generally said that the current limit for mounting with solder is that a lead pitch of 0.5 strands is stably possible, but
0.5 for multi-lead semiconductor devices with 300 pins or more
If a lead pitch of 6 is applied, the area of the semiconductor device becomes large, and the packaging density cannot be reduced. In recent semiconductor devices, the number of leads has increased significantly as their capacity has increased, but due to the above-mentioned problem of packaging density, film carrier semiconductor devices in particular can easily accommodate the number of leads on the OLB side, whereas ILBs can easily handle the number of leads. Due to restrictions, the mounting density is the same as other packages, and the leads are thin, making mounting difficult.

[Means to solve the problem]

The present invention provides a film carrier tape having at least a sprocket hole for conveyance and positioning, a device hole into which a semiconductor chip is inserted, and a plurality of leads each having one end protruding into the device hole, the other end of the lead being connected through a through hole. A film carrier tape that is connected to outer lead bonding pads provided on the opposite side of the film carrier tape, and has a structure in which the outer lead bonding pads are alternately arranged facing each other across the through hole rows. be.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1 and 2 are plan views of the front and back surfaces of a film carrier semiconductor device, respectively, showing an embodiment of the present invention.

As shown in FIGS. 1 and 2, the film carrier tape 6b has a sprocket hole lb and a device hole 3b.
and a lead 4b.

The semiconductor chip 2b has bumps 7b provided on the electrode terminals.
The lead 4b is bonded to the through hole 1 on the film carrier tape.
3b, it is connected to the OLB pad 14b on the back side of the film carrier tape, as shown in FIG.

The OLB pads 14b are arranged in two rows in a staggered manner and have buttons.
They are arranged alternately facing each other with two rows of through holes 13b in between, and one row of the two rows of bevel vice holes 3
b and through hole 13b, and is provided at a position through which the lead pattern on the surface of the film carrier tape on the opposite side passes.

The method for manufacturing the film carrier semiconductor device of this example is shown below.

1. As shown in FIGS. 1 and 2, a lead 4b with one end protruding into the device hole is provided on the surface of an insulating film made of polyimide or the like with a sprocket hole lb and a device hole 3btl, and The other end of the lead is connected to the through hole 13b, and the through hole 13
OLB pad 14b is attached to the back side of the insulating film through b.
A film carrier tape 6b is prepared. OL
The B pads 14b are alternately arranged facing the through holes 13b as described above.

Such a film carrier tape 6b having patterns on both sides can be easily manufactured by applying a ground tape commercially available from 3M Company in the United States. for example,
First, the polyimide film is selectively etched to form through holes, and then both sides of the polyimide film are thinly coated with Cu by electroless plating, and then only the pattern areas such as leads and OLB pads are selectively etched. Pattern formation and through-hole plating are performed by electrolytic plating of Cu, and further C
By etching u thinly, unnecessary thin Cu remaining between patterns is removed. Next, sprocket holes and device holes are selectively etched into the polyimide film, and the patterned portions are plated with Au+8n or the like to complete the process.

Next, the semiconductor chip 2b with the bumps 7b provided on the electrode terminals and the film carrier tape 6b are glued together as in the conventional case.
After bonding with the lead 4b, resin sealing is performed if necessary. Next, electrical selection is performed by applying a contact to the OLB pad 14b on the nose surface of the film carrier tape 6b.

Incidentally, electrical sorting may be carried out by providing a separate V electrical sorting pad on the surface of the film carrier tape as in the conventional method.

The method for mounting the film carrier semiconductor device completed in this way is to use an anisotropic conductive adhesive sheet between the bonding pad provided on the mounting board and the OLB pad provided on the back surface of the film of the film carrier semiconductor device. This can be easily carried out by sandwiching the film and applying heat and pressure from the surface of the film using a tool. For example, Nikkei My, i-long 1988 Yu1゜Kat1, Introduction 5ゎ, I,
8 Ritsukai Kogyo's anisotropic conductive sheet is approximately 150℃
It can be bonded at a temperature sufficiently low compared to the heat resistance of polyimide film.

When improving the connection reliability with the above-mentioned anisotropically conductive sheet, or when using anisotropically conductive rubber that establishes conduction by applying pressure, metal protrusions may be placed on the OLB pad of the film carrier semiconductor device. It is effective to provide

FIG. 3 is a sectional view showing an application example of this embodiment, in which a metal protrusion is provided, and the method of forming it is described in
2662. JP-A-60-194543. USP4,44
2,967, etc., only the Au pole 15b for wire bonding is formed on the OLB pad 14b.

FIG. 4 is a cross-sectional view showing the mounting state of the semiconductor device shown in FIG. 3. By inserting the bonding pad 12b and pressing from the opposite side of the Au ball 15b, conduction can be established and the device can be easily mounted.

In the above film carrier semiconductor device, OLB pads are placed on the film carrier tape instead of the OLH lead pattern, so there are no defects such as lead deformation, and OLB pads are arranged in two rows. This has the effect of maintaining a sufficient OLB pad pitch necessary for mounting, and since the lead pattern area for one row is used, the mounting area is not increased.

FIG. 5 is a sectional view of another application example of the present invention.

Similarly to the application example described above, solder projections 17C are formed by selectively applying solder plating to a thickness of about 10 μm or more on the OLB pads 14c arranged in a staggered manner using a photomask method.

Figure 6 is a cross-sectional view showing the mounting state υ, solder protrusion 1
7c is melted and connected onto the printed circuit board 11C. This application example eliminates the need for materials such as conductive rubber as in the above application example, and has the advantage that it can be manufactured all at once regardless of the number of pins.

〔Effect of the invention〕

As explained above, the present invention completely prevents lead deformation, which has been a problem in the past, by providing an OLB pad on the back side of the film carrier tape in place of the OLB lead, and also provides an OLB pad as a lead. By arranging the pads in a staggered manner, the spacing between the OLBs can be increased and short circuits can be prevented.

Also, by arranging OLB pads and dots facing each other across the through-hole, OLB pads can be made.

The lead pattern can be provided under the lead pattern on the opposite side, which has the effect of reducing the packaging density.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are plan views of an embodiment of the present invention, respectively;
FIG. 3 is a sectional view of the application example, FIG. 4 is a sectional view showing its mounting state, FIG. 5 is a sectional view showing another application example, FIG. 6 is a sectional view showing its mounting state, and FIG. The figure is a plan view of a conventional film carrier semiconductor device, FIGS. 8 and 9 are sectional views thereof, and FIG. 10 is a sectional view showing the mounting state thereof. 1a, 1b... Sprocket hole, 2a, 2
b. 2 C-...Semiconductor chip, 3a, 3b...
・Device hole, 4a, 4b...Lead,
5a...Electric screening pad, 5a, 5b, 5c
...Film carrier tape, 7a, 7b...
...Bump, 8a...Suspender 9a
, 9b, 9cm --- resin, lla. 1 l b, 11 C・-・°・Printed circuit board, 1
2a, 12b, 12c・Pa...bonding pad,
13b, 13C...Through hole, 14b, 1
4c...OLB pad, 15b...A
u ball, 16b... Anisotropic conductive rubber, 17c
...Solder protrusion.

Claims (2)

[Claims] (1) In a film carrier tape having at least a sprocket hole for conveyance and positioning, a device hole into which a semiconductor chip is inserted, and a plurality of leads with one end protruding into the device hole, the other end of the lead is connected through a through hole. It is connected to outer lead bonding pads provided on the opposite side of the film carrier tape, and has a structure in which the outer lead bonding pads are alternately arranged facing each other across the through hole rows. film carrier tape. (2) The film carrier tape according to claim (1), wherein a metal protrusion for connection to a bonding pad of a mounting board is provided on the outer lead bonding pad.