JPS61290734A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PURPOSE:To do precise and easy screening of semiconductor devices, by forming a fuse circuit for probe-inspection identification on a semiconductor pellet, and by marking the good-or-bad result of the probe inspection by employing cut or non-cut of the fuse circuit. CONSTITUTION:On a semiconductor pellet, a fuse circuit for probe-inspection identification is formed. The fuse circuit is comprised of a polysilicon layer 3 on a field insulating layer 2, a first passivation layer 5 having an opening 4, a wiring layer 6, and a second passivation film 9 having an opening 8 for a pad 7. When an electrical defect is found on any portion of the circuit as a result of the probe inspection, excess current flows across the pad 7 and the ground to melt the fuse circuit, thus identifying defective ones. In this way, precise and easy screening of semiconductor pellets can be done.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a technique that is effective when applied to the manufacture of semiconductor devices.

(Background Art) Semiconductor devices are usually manufactured by housing semiconductor pellets in a package.

The semiconductor pellets loaded at this time must be perfect. Therefore, at the wafer stage before semiconductor pellets are formed, circuit blocks, which are units of semiconductor pellets, are checked for defects, and only good pellets are selected after dicing. The result of the check is marked with ink or the like on a part of the circuit block on the wafer, and after dancing, it is possible to judge the quality of the semiconductor pellet based on the mark.

As a result, it is possible to know the number of non-defective products, so semiconductor devices can be manufactured after calculating the yield.
It becomes possible to manage the manufacturing process.

By the way, some types of semiconductor pellets require probe inspection more than once. For example, there is a case where an analog circuit and a digital circuit have significantly different limit voltages. In this case, each circuit must be probed separately using a tester with an appropriate voltage.

For semiconductor pellets that require multiple probe tests as described above, if the results of the probe test are marked as described above, the marks will be added for each test. Items with marks will also appear. That is, if one mark is attached when a defect is found in one circuit, then if two circuits are defective, there will be circuits with two marks attached.

Therefore, depending on the method of optically reading the number of marks and calculating the number of defective semiconductor pellets, the number of good semiconductor pellets is not accurate because pellets with defects in both circuits may be counted twice. There is a problem that it cannot be calculated.

The inventors have discovered that in order to make the above calculation possible, a large-scale device is required and it cannot be easily performed.

Regarding inspection of semiconductor devices, published by Science Forum, November 28, 1980,! It is explained in detail in ILsI Device Handbook JP254-P277.

[Purpose of the invention]

An object of the present invention is to provide a technique that allows easy selection of semiconductor pellets that require multiple probe inspections.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

That is, by forming a fuse circuit for probe test identification in a circuit block that requires multiple probe tests on a wafer, and recording the pass/fail result of the probe test as whether the fuse circuit is disconnected or not, the fuse circuit can be identified. Since the presence or absence of defects can be determined by the continuity test, accurate sorting of semiconductor pellets can be easily performed.

〔Example〕

FIG. 1 fal is a schematic plan view showing a fuse circuit formed in a bullet mounted on a semiconductor device according to a first embodiment of the present invention, and FIG. 1 fal is a sectional view of the fuse circuit. .

The above fuse circuit consists of a silicon substrate 1 of a semiconductor pellet.
A polysilicon layer 3 is formed on the field insulating layer (SiO□) 2 on top of the polysilicon layer 3, and a first puffing layer (SiO□) having an opening 4 through which a part of the polysilicon layer 3 is exposed is formed on the polysilicon layer 3. ) 5, an interconnect layer (AI) 6 is formed on the first passivation layer 5, and a second layer (AI) having an opening 8 for the pad 7 is formed on the interconnect layer 6.
It is constructed by forming a puffiness film 9. Its planar shape is shown in Figure 1 (al),
The constriction of polysilicon layer 3 is fuse 10 . This polysilicon layer 3 can be formed simultaneously when forming the gates of circuit elements on the wafer.

One end of the fuse circuit is electrically connected to pad 7, while the other end is connected to ground 1 as schematically shown in FIG.
1.

The semiconductor pellet mounted on the semiconductor device of Example 1 requires two probe inspections at the stage of a circuit block as large as a sea urchin fly to determine whether the circuit block is a good product or not. , the fuse circuit is used to record the results of the probe test. In other words, if an electrical defect in one of the circuits is found as a result of two probe tests, the defective product can be identified by passing an excessive current between the pad 7 and the ground and disconnecting it. It is something that can be done.

According to this method, only non-defective products are those that can establish continuity between the buff door and the ground 11, and these non-defective products can be easily identified by electrical means, making it possible to automate the counting of non-defective products.

In addition, in this case, if a defect is discovered during the first probe inspection, information as a defective product is recorded at that stage, so the next probe inspection can be omitted by reading this record. is also possible.

The semiconductor device of Example 1 is manufactured through normal manufacturing steps using semiconductor pellets of good quality formed by guising circuit blocks selected as good by the method described above.

As explained above, in the semiconductor device of Example 1, the probe inspection at the sea urchin fly level is carried out rationally, and the automation of process control such as the assembly process is promoted by automatic counting of good pellets, resulting in cost reduction. It is something that can be achieved.

Note that FIG. 2 is a cross-sectional view showing an example of the semiconductor device of the first embodiment. This semiconductor device is a so-called resin-sealed semiconductor device, and a semiconductor pellet 13 provided with the fuse circuit described above is attached to a tab 12 that is a pellet attachment portion. Electrodes of this semiconductor pellet 13 (not shown)
The inner ends of the leads 14 are electrically connected to each other via wires 15 made of gold or the like, and are molded and sealed with a resin pan cage 16.

[Example 2] This example 2 is a semiconductor device similar to the above-mentioned example 1, but two fuse circuits corresponding to the number of probe inspections in a sea urchin fly are formed on the mounted pellet. It is something.

That is, two fuse circuits formed in substantially the same manner as in the first embodiment are formed in a part of the pellet. As shown schematically in FIG. 3, the fuse 10 has pads 7 and 7a connected to both ends thereof.

The semiconductor pellet mounted on the semiconductor device of Example 2 records the results of two probe tests at the same time as the disconnection of two fuse circuits.
This makes it possible to easily identify good pellets.

For example, if it is decided to cut the fuse 10 when there is no defect, the product is good if no defect is found in both the first and second probe inspections, so the two fuses 10 are cut and electrical continuity is established. Only those that cannot be removed are considered to be of good quality.

Therefore, if the fuse is conductive at even one point, it can be excluded as a defective product, so the number of non-defective products can be accurately calculated, and counting can be automated.

〔effect〕

(1) By forming a fuse circuit for probe test identification in a circuit block that requires multiple probe tests on a wafer, and recording the pass/fail result of the probe test as whether the fuse circuit is disconnected or not. It is possible to determine whether a defect has developed or not by testing continuity of the fuse circuit.

(2) According to the above-mentioned (11), accurate sorting of semiconductor pellets can be easily performed, so automation of counting of non-defective products can be achieved.

(3) Through (2) above, automation of manufacturing process management is achieved.

(4) By forming one fuse circuit, performing successive probe inspections, and cutting the fuse when a defect is discovered in the circuit, defective products can be accurately identified even if subsequent probe inspections are omitted. Since it can be distinguished, the inspection process can be shortened.

(5) Through (3) and (4) above, cost reduction of semiconductor devices can be achieved.

(6) By forming a number of fuse circuits corresponding to the number of probe inspections, and cutting the corresponding fuses when no defects are found in each probe inspection, only those with all fuses cut are considered to be non-defective. Therefore, even if uninspected products are mixed in after dicing, only non-defective products can be sorted out, so it is possible to effectively prevent the occurrence of defective semiconductor devices due to uninspected products mixed in.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nor.

For example, although an example of two probe tests has been described, it goes without saying that the probe test can also be applied to cases where three or more probe tests are required.

Furthermore, although an example of two probe tests for a digital circuit and an analog circuit has been described, the present invention is not limited to this.

Further, in the first embodiment, an example was explained in which the fuse is cut when there is a defect, and in the second embodiment, when there is no defect, the fuse is cut, but the invention is not limited to these, and the opposite combination may be used. Needless to say.

[Application field]

In the above explanation, the invention made by the present inventor was mainly applied to a resin-sealed semiconductor device, which is the background field of application, but the invention is not limited thereto. It is an effective technique that can be applied to all types of semiconductor devices, regardless of the type of semiconductor device.

[Brief explanation of drawings]

FIG. 1(a) is a schematic plan view showing a fuse circuit formed in a bullet mounted on a semiconductor device according to a first embodiment of the present invention; FIG. 1(bl is a cross-sectional view of the fuse circuit); Figure 1 (
C) is a schematic explanatory diagram showing the connection state of the fuse circuit, FIG. 2 is a sectional view showing an example of the semiconductor device of the first embodiment, and FIG. FIG. 2 is a schematic explanatory diagram showing a connection state of a fuse circuit formed in a pellet mounted on the device. 1... Silicon substrate, 2... Field insulating layer, 3
... Polysilicon layer, 4... Opening, 5... First
Vanishing layer, 6... Wiring layer, 7... Pad, 8... Opening, 9... Second puffy basin film, 10... Fuse, 11... Ground, 12...
- Tab, 13... Semiconductor pellet, 14... Lead, 15... Wire, 16... Resin package. Figure 1 (α) Ri (C)

Claims (1)

[Scope of Claims] 1. A semiconductor device mounted with a pellet that requires multiple probe tests, the semiconductor device having a fuse circuit for probe test identification formed on the pellet. 2. The semiconductor device according to claim 1, wherein the fuse circuit is formed independently. 3. The semiconductor device according to claim 1, wherein the fuse circuit is formed as a part of the circuit. 4. By forming a fuse circuit for probe test identification in a circuit block formed on a wafer that requires multiple probe tests, and recording the result of the probe test as whether the fuse circuit is disconnected or not, In the subsequent process, only good pellets are selected depending on whether the fuse circuit is blown or not. 5. The method of manufacturing a semiconductor device according to claim 4, wherein the fuse circuit is formed independently. 6. The method of manufacturing a semiconductor device according to claim 4, wherein the fuse circuit is formed as a part of the circuit.