JPH0666392B2 - Method for manufacturing semiconductor device - Google Patents

Description

The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a so-called pelletizing method for separating a semiconductor wafer into individual elements.

[Conventional technology]

Conventional pelletizing, as shown in Figure 4 (a) ~ (d),
A semiconductor wafer (hereinafter, simply referred to as a wafer) 3 is attached to the surface of the first adhesive sheet 2 attached to the flat ring 1 (FIG. A), and then a play 4 having a thickness of about 20 to 50 μm is used. Wafer 3 to first adhesive sheet 2
To make a semiconductor element (hereinafter referred to as a pellet) 3 '(Fig. B) by making cuts 5 in a grid pattern at a depth reaching
A second adhesive sheet 6 larger than the first adhesive sheet 2 is attached to the back surface of the first adhesive sheet 2, that is, the surface opposite to the surface to which the pellets 3'are attached (FIG. C), The above-mentioned sheet is placed on the expansion ring 8 set on the base 7, and the end portion of the second adhesive sheet 6 is sandwiched by the expansion jig 9 and pushed down to expand the second adhesive sheet. Along with this, the first expansion sheet 2 was expanded by the method (FIG. D) for expanding the mutual intervals of the pellets 3 '.

Here, the interval between the pellets 3'is increased so that when the pellets 3'are picked up by pushing up with needles from the back side of the first and second adhesive sheets, adjacent pellets collide with each other, This is done to prevent the up jig from damaging by contacting adjacent pellets.

[Problems to be Solved by the Invention]

In the above-described conventional pelletizing method, the first adhesive sheet is indirectly expanded by expanding the second adhesive sheet, so that the peripheral portion of the second adhesive sheet is easily stretched.
The portion where the first and second adhesive sheets overlap is difficult to stretch,
There is a drawback that the mutual intervals of the pellets 3'cannot be sufficiently obtained. Particularly, in the case of a semiconductor element having a pellet size of about 1 mm, the number of cuts also increases, and the enlargement ratio of the first adhesive sheet must be increased in order to obtain a minimum pellet mutual interval (0.4 to 0.5 mm). . For that purpose, it is necessary to further increase the enlargement ratio of the second pressure-sensitive adhesive sheet, but before that, the second pressure-sensitive adhesive sheet was torn, and the above-mentioned necessary mutual interval of pellets could not be obtained.

[Differences from the Prior Art of the Invention]

It differs from the above-described conventional pelletizing method in that not only the overlapping portion of the first and second adhesive sheets can be efficiently enlarged, but also the enlargement ratio can be given directionality. .

[Means for solving the problem]

The method of pelletizing of the present invention comprises attaching at least two pieces of the third adhesive sheet to both the first and second adhesive sheets, and expanding the second and third adhesive sheets, It has a feature of enlarging the pressure-sensitive adhesive sheet of No. 1.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

FIG. 1 is a plan view (FIG. A) and a sectional view (FIG. B) showing an embodiment of the pelletizing of a linear sensor to which the present invention is applied. The linear sensor is an optical sensor in which 100 to 10000 photodiodes are arranged in a line, and the pellet size is a considerably long size of 1 mm x 5 to 100 mm. In the case of such pellets, the number of cuts in the wafer 3 is 100 or more in the X direction and 3 to 5 in the Y direction as shown in FIG. If the notch 5 of the wafer is to be widened to a distance of at least 0.4 to 0.5 mm, the enlargement ratio in the X direction must be increased. To achieve this, four strip-shaped third adhesive sheets 10 are used.
(a) It is effective to attach as shown in the figure. That is, a strip-shaped pressure-sensitive adhesive sheet having a width of about 25 mm and a length of about 50 mm is brought close to the X axis and is attached in a substantially symmetrical and radial manner with respect to the X axis and the Y axis. The overlapping width of the first and third adhesive sheets is about 10 mm
Then, the pressing by the expansion jig is made to be the overlapping portion of the second and third adhesive sheets. As a result, when enlarged by the method of FIG. 4, the enlargement of the first pressure-sensitive adhesive sheet becomes larger in the X direction than in the Y direction, and is enlarged in an elliptical shape as shown in FIG. 1 (c).

The enlargement ratios in the X and Y directions can be arbitrarily changed depending on the attachment position and the number of the third adhesive sheet.

For example, in the case of a linear sensor in which 5000 to 10000 photodiodes are arranged in a line, the pellet size is about 0.5 mm × 70 mm, and as shown in FIG. 2, effective pellets are in a line in the center of the wafer. I can only take it. In such a case, it is necessary to maximize the enlargement ratio in the X direction in the figure, and the third adhesive sheet 10 is
Just stick one. Of course, the size of the sheet 10 can be variously selected according to the materials and thicknesses of the first and second sheets, or the characteristics of the apparatus for enlarging the sheet. In this case as well, it goes without saying that the third sheet 10 needs to overlap a part of the first sheet 2 and the overlapping portion of the second sheet and the third sheet needs to be pressed by an expansion jig to be expanded. Yes.

Further, if it is desired to increase the enlargement ratio in the Y direction, the third adhesive sheet may be attached to the Y-axis as shown in FIG.
However, in the example of FIG. 3, since the dimensional ratio of the pellets in the X and Y directions is not so large as compared with the case of the previous example, the third adhesive sheet can be attached at an angle opened with respect to the Y axis.

Needless to say, the shape of the third adhesive sheet is not limited to a strip shape, and can be arbitrarily selected according to various characteristics such as an enlargement device and elongation rates of the first and second adhesive sheets such as an ellipse and a triangle. .

〔The invention's effect〕

As described above in detail, according to the present invention, the enlargement ratio of the wafer in the X direction and the Y direction can be arbitrarily changed,
Even for pellets having an extremely large aspect ratio such as an area sensor, the required pellet spacing can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view (a, c) and a cross-sectional view (b) showing an embodiment of the present invention, FIG. 2 and FIG. 3 are plan views showing another embodiment of the present invention, and FIG. [FIG. 6] is a cross-sectional view showing a conventional manufacturing method. 1 ... flat ring, 2 ... first adhesive sheet, 3
... Semiconductor wafer, 3 '... Semiconductor element (pellet), 4 ... Blade, 5 ... Notch, 6 ... Second adhesive sheet, 7 ... Table, 8 ... Expansion ring, 9 ... Expansion cure Tool, 10 ... Third adhesive sheet.

Claims (1)

[Claims] 1. A first adhesive sheet is attached to the back surface of a semiconductor wafer, and the semiconductor wafer is provided with notches in a grid pattern at a depth reaching the first adhesive sheet, and the first adhesive sheet is further provided. On the surface of the semiconductor wafer facing the semiconductor wafer.
A second adhesive sheet larger than the first adhesive sheet, and enlarging the second adhesive sheet to enlarge the mutual position of the cut semiconductor wafer pieces. And at least two pieces of the third pressure-sensitive adhesive sheet are attached to both surfaces so as not to overlap each other across only the second pressure-sensitive adhesive sheet, and the second and third pressure-sensitive adhesive sheets are enlarged so that the first pressure-sensitive adhesive sheet is expanded. 1. A method for manufacturing a semiconductor device, which comprises enlarging the pressure-sensitive adhesive sheet of 1.