JPS61259536A - Inspecting device for semiconductor wafer - Google Patents

Abstract

PURPOSE:To improve the efficiency of a trouble case search by placing the shape or material of the edges of a plurality of styluses of a scratching marker to immediately detect the stylus which has a damage on a semiconductor chip. CONSTITUTION:When chips on a semiconductor chip are measured, for example, with four as a unit, four styluses having edges (a)-(d) are mounted on a scratch marker. Then, four types of improper identifying marks are attached. Since these markers can be distinctly distringuished, the marks of the styluses can be observed at a glance. Thus, this can largely contribute to a trouble search in the inspecting steps of a wafer.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a semiconductor wafer inspection apparatus.

[Conventional technology]

,, A large number of semiconductor devices (hereinafter referred to as semiconductor chips) separated by scribe lines are formed on a semiconductor wafer. Before these semiconductor chips are separated into individual chips, the electrical characteristics of each chip are measured, and the surface of the chip determined to be defective is scratched, for example, with a needle, as a defect identification mark. These defective chips are then separated in a dicing process and then selectively removed.

This scratch for identifying defects is made with a scratch marker immediately after measuring the electrical characteristics. When a plurality of semiconductor chips, for example, four chips B, C, and D arranged side by side as shown in FIG. 3, are measured simultaneously by the probe of the probe card, the scratch marker has Four needles corresponding to these four chips are provided.

When the fourth chip of A=D□ is determined to be defective, these four needles simultaneously scratch the surfaces of the four chips as defect identification marks.

In the inspection process for semiconductor chips on which semiconductor devices have been formed, the semiconductor chip may be judged as defective even though it is not defective due to failure of the scratch marker or failure of the measuring device.
Alternatively, all the products may be determined to be good.

For example, as shown in FIG. 3, the results of inspecting chips in units of four indicate that among chips 2 on semiconductor wafer 1, all of the chips in rows A, 1, and N2 are found to be defective, as shown in FIG. If a defective identification mark 3 is attached to the chips, or if all the chips in the C1 and C2 rows are determined to be good, it is necessary to immediately investigate the cause.

As soon as it is determined which of the multiple needles (four in this case) the needle that has been continuously judged to be good or defective is identified, the condition of the needle, the scratch marker, the measurement system, the manufacturing process, etc. can be immediately investigated. The cause can be investigated.

[Problem that the invention seeks to solve]

However, since the shape and material of the tips of the scratch marker needles are all the same, the shapes of the scratches made are also the same, and it is therefore difficult to immediately determine which needle has successively judged semiconductor chips as good or defective. This has the disadvantage that investigating the cause requires a lot of man-hours.

The purpose of the present invention is to eliminate the above-mentioned drawbacks and to immediately remove the needles that caused the scratches from the ulcers made on the semiconductor chip by changing the shape and/or material of the needle tips of the plurality of needles of the scratch marker. An object of the present invention is to provide a semiconductor wafer inspection device that can detect semiconductor wafers.

[Means to solve the problem]

The semiconductor wafer inspection device of the present invention has a function of simultaneously measuring the electrical characteristics of a plurality of semiconductor chips formed on a semiconductor wafer, and has a plurality of needles corresponding to the measurement chips between the plurality of electrical characteristics. An inspection device having a scratch marker that scratches the surface of a defective chip with a characteristic characteristic,
The needle tips of the scratch markers have different shapes and/or materials.

According to the present invention, since the shapes of the scratches made by each needle of the scratch marker are all different, it is possible to immediately know which needle made the scratch on the chip which is the defective work mark.

〔Example〕

Next, embodiments of the present invention will be described using the drawings.

FIGS. 1(a) to (d) are plan views showing the shape of the tip of a scratch marker needle used in one embodiment of the present invention, and FIGS. FIG. 3 is a diagram showing the shape of a scratch formed on a chip by the tip.

For example, the needle of a scratch marker with the needle tip shown in FIGS. 1(a) and (b) is pushed out diagonally above the surface of the chip when the electrical characteristics of two corresponding chips are determined to be poor. , due to the tip of the needle, Figure 2(a), (
A scratch as shown in b) is formed on the chip surface.

When four chips on a semiconductor wafer are measured as one unit as shown in Figure 3, for example, Figure 1 (a)
) ~ If four needles with the needle tips shown in (d) are attached to the scratch marker, four types of defect identification marks will be attached, and these marks are shown in Figure 2 fa) ~
Since they are clearly distinguishable as shown in (d), it can be seen at a glance by which needle the identification mark was applied.

The flaw, which is a defect identification mark, can be made easily visible by appropriately selecting it depending on the surface condition of the semiconductor chip, for example, whether a thick protective film is formed or whether there are many wirings. Further, even if the needle tip has the same shape, it is possible to change the state of the wound by changing its material.

For example, if the needle tip is made of iron or diamond, the scratches will be shallow in the former case and deep in the latter case. Therefore, the amount of light reflected from the surface of a pellet with scratches is greater when the scratches are shallow than when the scratches are deep, and because the scratches have different hues, they can be clearly distinguished visually or by a sensor. .

In this way, by appropriately combining the shape of the needle tip and its material, it is possible to obtain a large number of needle tips that are capable of creating different scratches. For this reason, the shapes and/or materials of the needle tips of the plurality of needles included in the scratch marker can all be made different, so it becomes easy to find the correspondence between the needles and the scratches.

Therefore, in the semiconductor wafer inspection process, if all of a particular row is determined to be good or defective as shown in Figure 4, the needles of the corresponding scratch markers can be immediately identified. The condition can be checked, and if there are no abnormalities, the investigation can proceed quickly to the condition of the scratch marker, then to the measuring device and manufacturing process.

In the above embodiment, a scratch marker having four needle tips of different shapes has been described, but the present invention is not limited thereto, and needles having needle tips of various other shapes may be used. Of course.

〔Effect of the invention〕

As described above in detail, the present invention provides a semiconductor wafer inspection apparatus that can immediately identify the scratch marker needle that has caused a scratch on a chip, which is a defect identification mark, in the semiconductor wafer inspection process. Therefore, it is highly effective in investigating troubles in the semiconductor wafer inspection process.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the needle tip of a scratch marker needle used in an embodiment of the present invention, FIG. 2 is a diagram showing the shape of the scratch made by the needle tip shown in FIG. 1, and FIG. 4 is a diagram for explaining electrical measurement of a semiconductor chip, and FIG. 4 is a diagram showing inspection results of a semiconductor wafer. 1... Semiconductor wafer, 2... Chip,
3... Defective identification mark (paper). 1st (CI) (b) (C) (d) Kaya 2
Figure I V e IN ((21lb) (C) (d) Kaya
3 times 4y! J

Claims (1)

[Claims] It has the function of simultaneously measuring the electrical characteristics of multiple semiconductor chips formed on a semiconductor wafer, and has multiple needles corresponding to the multiple measurement chips, and is capable of scratching the surface of chips with defective electrical characteristics. What is claimed is: 1. A semiconductor wafer inspection device having a scratch marker for marking a semiconductor wafer, wherein the diagonal tips of the plurality of needles have different shapes and/or materials.