JPH1187604A - Semiconductor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the manufacturing cost and the manufacturing time of a lead frame by omitting a processing and a sticking step of a polyimide tape, and to eliminate a defective shape of a lead frame to thereby reduce the reliability of the device. To improve SOLUTION: The lead frame 11 is bonded to a single-layer thermoplastic silicon-modified polyimide 14 applied on the upper surface of a semiconductor chip 13 to thereby form a lead frame 1.
1, the upper surface of the semiconductor chip 13 is fixed. This allows
Since it is not necessary to equip the lead frame 11 with a polyimide tape, a processing step of processing the polyimide tape into an arbitrary shape and an attaching step of attaching the cut polyimide tape to a predetermined position of the lead frame 11 are omitted. Can be.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-encapsulated semiconductor device and a method of manufacturing the same, and more particularly, to a LOC (Lead On On).
The present invention relates to a structure in which a semiconductor chip is fixed to a lead frame in a package structure.

[0002]

2. Description of the Related Art In recent years, semiconductor chips have become larger in size with higher integration of semiconductor devices, which has led to larger packages. As one method for solving this problem, a resin-encapsulated semiconductor device having a LOC structure in which a lead frame (envelope terminal) is fixed on a circuit forming surface of a semiconductor chip has been used.

A resin-sealed semiconductor device having this LOC structure is provided on the lower surface of a lead frame 1 as shown in FIG.
And a polyimide coating (not shown) on the lower surface of the polyimide tape 2 to prevent the occurrence of errors due to alpha rays as shown in FIGS. The semiconductor chip 3 covered with is fixed. The semiconductor chip 3 and the lead frame 1 are electrically connected by wire bonding using a bonding wire (not shown). Then, the semiconductor chip, the lead frame, and the bonding wire are sealed and covered with an insulating resin (not shown).

[0004]

When a semiconductor device having a LOC structure is manufactured as described above, a lead frame on which a polyimide tape is mounted is required. In order to form the lead frame, the polyimide tape is formed into an arbitrary shape. Cutting process (hereinafter referred to as processing step)
Then, a taping step (hereinafter, referred to as an attaching step) of attaching the cut polyimide tape to a predetermined position of the lead frame is required.

[0005] In these processing steps and the sticking step, there is a problem that the lead frame has a defective shape due to the miniaturization of the polyimide tape, thereby reducing the reliability of the semiconductor device. Further, since the lead frame on which the polyimide tape is mounted is manufactured through the processing step and the attaching step, the manufacturing time of the semiconductor device is increased, and the manufacturing cost of the lead frame is increased. There was a problem that also becomes high.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems in the prior art, and aims to reduce the manufacturing cost and the manufacturing time of a lead frame by omitting a processing step and a bonding step of a polyimide tape. It is possible,
Further, it is an object of the present invention to provide a semiconductor device capable of improving the reliability of the device by eliminating the shape defect of the lead frame, and a method of manufacturing the same.

[0007]

In order to achieve the above object, a first aspect of the present invention is a semiconductor chip having a circuit formed on a surface thereof, a lead frame electrically connected to the semiconductor chip, A single adhesive layer made of a thermoplastic adhesive that is directly applied to the circuit forming surface of the semiconductor chip and adheres the lead frame and the circuit forming surface of the semiconductor chip; and the lead frame and the semiconductor chip. And a wire for electrical connection.

According to the first aspect of the present invention, the lower surface of the lead frame is bonded to an adhesive layer such as a single silicon-modified polyimide which is also used for countermeasures against alpha rays and is directly applied to the circuit forming surface of the semiconductor chip. Therefore, it is not necessary to equip the lead frame with a polyimide tape, so that the processing step of attaching the polyimide tape to be attached to the lower surface of the lead frame and the attaching step to the lead frame are omitted, and in a very simple form. The lead frame is fixed to the semiconductor chip.

A second aspect of the present invention is characterized in that a semiconductor chip having a circuit formed on a surface thereof, a lead frame electrically connected to the semiconductor chip, and the lead is applied directly to a circuit forming surface of the semiconductor chip. A single adhesive layer made of a thermoplastic adhesive for adhering a frame and a circuit forming surface of the semiconductor chip, wires for electrically connecting the lead frame and the semiconductor chip, the semiconductor chip and the leads There is provided a frame and a package formed by sealing a resin around the wires.

According to a third aspect of the present invention, in the first or second aspect, a step of applying a single adhesive layer made of a thermoplastic adhesive to a circuit forming surface of the semiconductor chip; Fixing the circuit forming surface of the semiconductor chip to the lower surface of the semiconductor chip with the adhesive layer.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line BB of FIG. Referring to the figure, a silicon-modified polyimide 14 is applied on the circuit-forming surface of semiconductor chip 13, and the circuit-forming surface of the semiconductor chip is fixed to the lower surface of lead frame 11 by this silicon-modified polyimide 14. Further, the lead frame 11 and the semiconductor chip 13 are electrically connected by wire bonding using the wires 15.

In the case of the present embodiment, the lead frame 11 is formed by cutting a metal material or the like. Separately from the production of the lead frame 11, a thermoplastic, single-composition silicon-modified polyimide 1 is formed on the circuit forming surface of the semiconductor chip 13.
4 is applied by spin coating.

Next, the circuit forming surface of the semiconductor chip 13 is fixed to the lower surface of the lead frame 11 which has been prepared in advance, using silicon-modified polyimide 14. After that, the semiconductor chip 13 and the lead frame 11 are electrically connected by wire bonding using the wires 15 and then sealed with an insulating resin and packaged.

Here, as a method of applying the above-mentioned polyimide 14 on a semiconductor chip, as a chip surface protective film used in a semiconductor manufacturing process, a thermoplastic resin used in a polyimide tape instead of a conventional polyimide resin is used. The silicon-modified polyimide resin described above may be used, and thereafter, the patterning may be performed in the conventional manner.

According to the present embodiment, the semiconductor chip 13
Since the silicon-modified polyimide 14 applied thereon plays a role of fixing the lead frame 11 and the semiconductor chip 13, there is no need to attach a conventionally cut polyimide tape to a predetermined position of the lead frame 11. Thus, the steps of processing and attaching the polyimide tape can be omitted.

Moreover, the processing and sticking costs of the polyimide tape, which were conventionally required, account for about 40% or more of the manufacturing cost. In this example, since these steps are omitted,
The manufacturing cost of the semiconductor device can be significantly reduced, and the manufacturing time of the semiconductor device can be reduced.

By omitting the two steps described above, not only can the shape defect of the lead frame 11 due to miniaturization of the polyimide tape be eliminated, but also the semiconductor chip 13
And the lead frame 11 can be fixed with a single layer of the silicon-modified polyimide 14, so that the reliability of the manufactured semiconductor device can be improved.

The semiconductor chip 13 and the lead frame 1
The thermoplastic synthetic resin for fixing 1 is not limited to the silicon-modified polyimide 14 described above, and the same effect can be obtained by using any other suitable resin as long as it is an adhesive resin that does not transmit alpha rays and has an adhesive property. In particular, patterning can be performed using photosensitive polyimide. In addition, it goes without saying that the above-mentioned silicon-modified polyimide 14 also fulfills the function of preventing alpha rays.

Further, when the thermoplastic silicon-modified polyimide 14 is applied to the upper surface of the semiconductor chip 13 by the spin coating described above, the thickness can be easily changed to an arbitrary thickness. Therefore, by controlling the film thickness, foreign matters such as chips on the upper surface of the semiconductor chip 13 are taken into the polyimide 14 layer, and the foreign matter is formed on the upper surface of the semiconductor chip 13. It is easy to make the film thickness so as not to damage the film.

[0020]

As described above in detail, according to the semiconductor device and the method of manufacturing the same of the present invention, the manufacturing cost and the manufacturing time of the lead frame can be reduced by omitting the processing and attaching steps of the polyimide tape. It is possible to improve the reliability of the device by eliminating the shape defect of the lead frame.

[Brief description of the drawings]

FIG. 1 is a plan view of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a plan view showing an example of a conventional lead frame.

FIG. 4 is a plan view showing an example of a shape of a polyimide tape mounted on the lead frame shown in FIG. 3;

FIG. 5 is a plan view showing an example of a conventional semiconductor device.

6 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Lead frame 13 Semiconductor chip 14 Silicon-modified polyimide 15 Wire

Claims (3)

[Claims] 1. A semiconductor chip having a circuit formed on a surface thereof, a lead frame electrically connected to the semiconductor chip, and a lead frame which is directly applied to a circuit forming surface of the semiconductor chip to form a connection between the lead frame and the semiconductor chip. A semiconductor device comprising: a single adhesive layer made of a thermoplastic adhesive for bonding a circuit forming surface; and a wire for electrically connecting the lead frame and the semiconductor chip. 2. A semiconductor chip having a circuit formed on a surface thereof, a lead frame electrically connected to the semiconductor chip, and a semiconductor chip having a circuit formed directly on the circuit forming surface of the semiconductor chip. A single adhesive layer made of a thermoplastic adhesive for bonding the circuit forming surface, a wire for electrically connecting the lead frame and the semiconductor chip, and a periphery of the semiconductor chip, the lead frame and the wire And a package formed by sealing a resin. 3. A step of applying a single adhesive layer made of a thermoplastic adhesive to a circuit forming surface of the semiconductor chip, and fixing the circuit forming surface of the semiconductor chip to the lower surface of the lead frame by the adhesive layer. 3. The method of manufacturing a semiconductor device according to claim 1, further comprising the step of: