JPH02123757A - Resin sealed semiconductor device characterized by high heat-resistance - Google Patents

Abstract

PURPOSE:To prevent the occurrence of deterioration and disconnection at a connecting part of an Al pad and an Au wire on an Si element by constituting a semiconductor device with a thermosetting resin layer comprising a specified material. CONSTITUTION:A semiconductor device is composed of a thermosetting resin layer whose weight reducing rate in heating when 200 deg.C is kept for 1,000 hours is 0.5% or less and whose size reducing rate is 0.05% or less. As the thermosetting resin, epoxy resin, polyester resin, polyimide resin, polyamide resin and the like are listed. In this constitution, deterioration and disconnection at the connecting part of an Al pad and an Au wire on an Si element are prevented under the high temperature state of 200 deg.C for a long time of 1,000 hours.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermosetting resin-encapsulated semiconductor device with excellent heat resistance.

[Conventional technology]

The heat resistance test for resin-sealed semiconductor devices is 12 times for consumer use.
5°C, i, ooo time (h), 150”C for industrial use
, 1,0OOh has been commonly practiced. These tests are for predicting life under normal use conditions, e.g. continuous operation at an ambient temperature of 55°C, and at 150"C, 1
, 0OOh, it is generally estimated that it has a lifespan of 5 years or more under normal use, and this relationship holds true in reality.

Recently, the quality of resin-sealed semiconductor devices has improved and the mass production effect has reduced costs, resulting in a dramatic expansion of applications. As part of this expansion of applications, resin-encapsulated semiconductor devices are now being adopted in the information and communications field, where conventionally only ceramic-encapsulated semiconductor devices have been used to ensure high reliability. It's here. Ceramic-encapsulated semiconductor devices have been proven to have a lifespan of more than 20 years when operated at 55°C, and accelerated tests at 175°C and 120°C have been conducted to predict this.
It is evaluated to be able to withstand even 00 hours.

However, as mentioned above, resin-encapsulated semiconductor devices have traditionally been able to withstand temperatures of 125°C, 150°C, and 1.0OOh, but it is difficult to withstand heat resistance tests of 175°C and 2.0OOh. I realized that this improvement was necessary. 175
When an accelerated test is performed at 12,000h at °C and 1,000h at 200°C to further shorten the test, it is found that the
The problem is that the joint of the U-wire is relatively easily eroded and disconnected.

Under conventional test conditions 125-150"C1,000h,
No such deterioration or disconnection of the Al-Au joint occurred. Therefore 175°c12°000h and 2
It became necessary to tackle the prevention of deterioration and disconnection of the AR-Au joint at 00°C and 1.0OOh as a new issue.

Problems to be Solved by the Invention] The present invention solves the problem that the Al-Au joint in a resin-sealed semiconductor device is susceptible to deterioration and disconnection during accelerated tests at 175°C for 12,000 hours and 200°C for 1,000 hours in conventional components. The purpose is to solve the problem.

[Means to solve the problem]

The present inventors have discovered that the angle of 20° in a resin-sealed semiconductor device is
When C1i, oooh's descendant temperature long-term heat resistance test was conducted,
In order to prevent the occurrence of deterioration and disconnection at the joint between the F-pad on the Si element and the Au wire, we conducted a detailed study from the viewpoint of the material of the constituent sealing material. As a result, the inventors discovered that the above-mentioned problems could be solved by constructing a semiconductor device using a thermosetting resin layer made of a specific material, and completed the present invention.

That is, the present invention constitutes a semiconductor device with a thermosetting resin layer having a heating weight reduction rate of 0.5% or less and a dimensional reduction rate of 0.05% or less after being held at 200°C for 1.000 hours. This feature provides a semiconductor device with excellent heat resistance, in which the Al-Au joint is stable even at 200°C1I, 0OOh and does not deteriorate or break.

If the heating weight reduction rate exceeds 0.5% or the dimensional reduction rate exceeds 0.05%, the desired heat resistance cannot be satisfied.

The heating weight loss rate and dimensional change rate were measured by the method described in Examples below.

In the present invention, examples of the thermosetting resin used include epoxy resins, polyester resins, polyimide resins, and polyamideimide resins.

〔Example〕

Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

Using 8 types of various sealing materials, D according to the molding conditions in Table 1.
Thirty pieces of each IP16piN were molded.

The element used was 5μm(7)A 1. This is a 7% 4M test chip with a wiring pattern. The gold wire is 25μmφ
(SR type manufactured by Nichi-no-Kizoku), and bonding was performed with a salmonic wire bonder (manufactured by Nippon Avionics). Each test element had eight bonding wires, and a failure was determined by a continuity test from a lead bin, and if even one of the eight bonding wires had a continuity failure, all of them were counted as failures.

The surface weight reduction rate and dimensional reduction rate were measured using a 127' x 12.7'' x 6.1L test piece molded under the conditions in Table 1.
= 5, the weight reduction rate was measured using a precision balance, and the dimensional reduction rate was measured using a vernier caliper as a change of 127 mm in the length direction. Test results are shown as average values for each sample.

Each sample "C) subjected to f$WJ was left in a constant temperature bath for 1,000 hours. Figure 1 shows the relationship between the weight loss rate and gold wire breakage defect rate after 1,000 hours at 200°C for each sample. The figure shows 200 of each sample.
The figure shows the relationship between the dimensional reduction rate after °C, 1, OOOh and the gold wire breakage defect rate. 0.5 in terms of weight reduction rate
% or less, and from the dimensional reduction rate of 0.05% or less, it can be seen that no disconnection defects have occurred. FIG. 3 shows these correlations in relation to the disconnection defect rate. If the weight reduction rate is 0.5% or less and the dimensional reduction rate is 0.05 or less, it can be seen that no disconnection failure occurred after 200°C 11,000h.

[Effect of the invention] According to the present invention, a resin-sealed semiconductor device of 200″C1i,
In the high temperature long-term test of oooh, A1 on the Si element
Deterioration and disconnection of the bond between the pad and the Au wire can be prevented. As a result, the operating life of the resin-sealed semiconductor device under normal usage conditions, which was conventionally said to be 5 years or more, can be dramatically extended to 20 years or more.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the weight reduction rate and the gold wire breakage failure rate. FIG. 2 is a graph showing the relationship between the dimensional change rate and the gold wire breakage failure rate. FIG. 3 is a graph showing the relationship between weight loss rate, dimensional change rate, and gold wire breakage defect rate. 200'C, 1000hKtt(n!t*・, dael('
/=)Figure 200@C, 1oooh'5kLr1'T 2'JX・
y drop ('/=) 2nd Figure 200'C, I (X: It; Au collar (ya ω)
Figure 3

Claims (1)

[Claims] 1. A thermosetting resin layer comprising a thermosetting resin layer having a weight reduction rate of 0.5% or less and a dimensional reduction rate of 0.05% or less after being held at 200°C for 1,000 hours. resin-encapsulated semiconductor device.