JPS6042843A - Semiconductor wafer - Google Patents

Abstract

PURPOSE:To secure the test position by elimination of the photo irregular reflection at the line at the time of pellet characteristic test with a line as the base line by a method wherein, when scribe lines for pellet splitting are provided in the semiconductor wafer, a metallic film is adhered along the line while excluding the center of the line. CONSTITUTION:Groove-form scribe lines 2 for pellet splitting are formed in the surface of the semiconductor wafer 1. At this time, the part other than the center 2a of the line 2 is kept covered with the metallic film 3 of Al or the like. In other words, the film 3 is formed in checkered form by being extended from the line 2 to the peripheral edge of a chip 4 the pellet. In such a manner, when the characteristics of each chip 4 are tested by means of a multi-probe device with the line 2 as the base line, the detection of the secure position is enabled without photo irregular reflection at the line 2.

Description

[Detailed description of the invention] The present invention relates to semiconductor ware 7.

Conventionally, semiconductor wafers with vapor-deposited wiring are subjected to characteristic tests using a so-called multi-probe device having a mechanical contact probe. When performing this characteristic test, it is first necessary to set the semiconductor wafer at a test position using a test device. To this end, when a semiconductor wafer is installed, it is necessary to be able to read its installation position and to be able to adjust the installation position according to the read position. In this way, the semiconductor wafer can be placed in the required test position, and once installed, the required test or test is automatically and continuously carried out for each individual chip according to the automatic operation of the test equipment. becomes possible. The installation position can be read by selecting an arbitrary base point (or base line) on the semiconductor wafer, reading it optically, and knowing the position of this reading position from the vertical and horizontal reference line. be.

Conventionally, a scribe line has been used as this baseline. This scribe line is for scribing a semiconductor wafer in the shape of a substrate, and a conventional scribe line will be explained. FIG. 1 is a plan view of a conventional semiconductor wafer (A), with scribe lines (a)
is formed in the shape of a base. FIG. 2(,) is a partially enlarged view of the semiconductor wafer (A) in FIG.
1]) is a sectional view taken along the line ■-■ in FIG. 2(a).

Since the scribe line a is formed by plasma etching, the scribe line ib has a highly uneven shape in the direction of the scribe line.

Even if such scribe line El is irradiated with light for base line detection and an attempt is made to detect scribe line a using the reflected light, the light will be diffusely reflected by the edge l) of the unevenness, and as a result, the detection signal C The waveform of is shown in Figure 2 (c
). That is, the detection center position d of the baseline detection signal 0 does not match the center position e of the scribe line a, and an error of distance f occurs between the two positions d and e. Therefore, in the conventional example, when the base line ' is detected by the scribe line, a detection error is likely to occur when the detection center position d by the scribe line detection signal C is detected as the center position Ne of the scribe line a, and position d.

The two positions are matched by taking into account the difference in e.

However, there were some drawbacks such as the long time required for detection.
An object of the present invention is to solve the above-mentioned technical problems and provide a semiconductor wafer whose position can be easily detected for testing the characteristics of chips on the semiconductor wafer.

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 is a plan view of one embodiment of the present invention.
The figure is an enlarged plan view of a part thereof, and FIG. 5 is a view corresponding to FIG. 2, and FIG. FIG. 5(1)) is a sectional view taken along the line V-V in FIG. 5(,), and FIG. 5(c) shows the base line detection signal of the multi-probe device.

The semiconductor wafer (1) according to the present invention has a groove-shaped scribe line (2) and
) A metal coating (3) made of aluminum or the like is formed by a method such as photo-etching, except for the central part (2a). This metal coating (3) is shown in FIG.
), it extends from the scribe line (2) to the periphery of the semiconductor chip (4). This metal coating (3)
are formed in the shape of a base along the scribe line (2).

As described above, in the semiconductor wafer (1) according to the present invention, since the metal coating (3) is formed on the scribe line (2) except for the central part (2a), the scribe line (2) can be used as the base line on the semiconductor wafer 7. When performing a characteristic test using a multi-probe device, light is not diffusely reflected at the scribe line (2). As a result, as shown in Figure 5 ('C), the detection center (9) indicated by the baseline detection signal (7)
and the true center (8) exactly match, which ensures reliable position detection. Note that this metal coating (
3) It becomes possible to display a certain display, such as a code number or a fail mark, on the screened portion.

Further, this metal coating (3) also serves as a force guard to prevent ion implantation from the outside. Furthermore, if the metal coating (3) is formed over the entire surface, it will also have a shielding effect.

In the above embodiment, aluminum was described as the metal coating (3), but as a further embodiment of the present invention,
It may be formed by vapor depositing tantalum, which makes it possible to prevent clogging of the outer dicer when the semiconductor wafer 7(1) is scribed. The metal coating (3) may be formed by sputtering instead of this vapor deposition.

In addition, as a means for recognizing the scribe line, there is a method using a laser, but a television or C, C, D can also be used.

As described above, according to the present invention, since the metal coating is formed along the scribe line and except for the central part of the scribe line, the light irradiated to the scribe line is not diffusely reflected, and thereby the semiconductor It is possible to reliably and easily detect the position of the wear 7 chip for characteristic testing. Furthermore, it becomes possible to display a certain mark on the metal coating.

[Brief explanation of the drawing]

Figures 1 and 2 show a conventional example; Figure 1 is a plan view;
Figure 2 (a) is a partially enlarged view of Figure 1, Figure 2 (1)) is a sectional view taken along the line ■-■ in Figure 2 (8), and Figure 2 (C) shows the baseline detection signal. 3 to 5 show an embodiment of the present invention, FIG. 3 is a plan view, FIG. 4 is a partially enlarged view of FIG. 3, and FIG. Co., Ltd. Agent Patent Attorney Oka 1) Hide Kazu Figure 1 Figure 3 Figure 2 Figure 4IA 97

Claims (1)

[Claims] (1) One semiconductor with a metal coating formed along the scribe line and excluding the central part of the scribe line.