JPS58142543A - Dicing method for semiconductor substrate - Google Patents

Abstract

PURPOSE:To dice an Si substrate into chips without producing cracks by a method wherein an adhesive sheet is adhered on the Si substrate and the substrate is bent. CONSTITUTION:An adhesive sheet 23 whereon a substrate 30 to be diced is adhered is fixed by holders 21 and 22, then a hollow part 24 is evacuated, and a gas is introduced into a hollow part 25 to a high pressure. Thereat, a force whereby the sheet 23 becomes a ball form generates thereon, then this force is applied on the bottom of grooves formed on the substrate 30, and accordingly it is diced into individual chips 32. Thereafter, the chips 32 are removed from the holders 21 and 22, and selected by a magnifier, etc. By this method, the substrate can be splitted with good yield.

Description

[Detailed description of the invention] The present invention relates to a method for dividing a semiconductor@board.

In the manufacturing process of semiconductor devices, each semiconductor device formed on a semiconductor wafer is processed through 1 dicing (scribing) 1, division 2, and die-ponding 3 as shown in Figure 1.
, wire bonding 4, sealing 6, and characteristic testing 6 before packaging. In such a process, the conventional method of dividing semiconductor sea urchins...
- Cut grooves are formed on the scribe lines formed on the surface by dicing and scribing. Next, as shown in FIG. 2(a), the semiconductor wafer 10 on which these grooves 18 have been formed is placed on a hard rubber 13 covered with a surface protection sheet 12 so that the back side of the four semiconductor wafers faces upward. Then, an electrostatic sheet 11 is placed on the semiconductor wafer 1o, and brought into close contact with the semiconductor wafer 1o1 and the protective sheet 12 around it.

Next, as shown in FIG. 2(b), the semiconductor wafer 1 is placed in close contact with the protective sheet 12 on the hard rubber rubber 13 and the electrostatic sheet 11.
A roller 14 is brought into contact with the back surface of the semiconductor wafer 1o to apply a load to the back surface of the semiconductor wafer 1o. When a load is applied to the back surface of the semiconductor wafer 10, the portion of the hard rubber sheet 13 where the load is applied collapses, and as a result, the load concentrates on the groove bottom 14 formed in the semiconductor wafer 10, causing it to crack. In this way, a load is applied to the back surface of the semiconductor sea urchin 10, as shown in FIG. 2(C).
It is divided into individual semiconductor chips 16 as shown in FIG.

However, in such a conventional semiconductor substrate dividing method, the chips 16 of the semiconductor wafer that are generated when a load is applied to the back surface of the semiconductor wafer 10 are
There is a risk that the surface of the semiconductor chips may be damaged or the semiconductor chips may come into contact with each other, causing cracks 17 and reducing the yield.

The present invention does not apply intensive load from the surface of the semiconductor wafer to a roller, etc., as in the conventional method.
This method provides a method for dividing semiconductor substrates into semiconductor chips by uniformly applying pressure due to a pressure difference to the entire back surface of a semiconductor substrate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for dividing a semiconductor substrate according to the present invention, which aims to divide the semiconductor chips into individual semiconductor chips without causing damage due to fragmentation and without cracking the semiconductor chips, will be described in detail with reference to the drawings. FIG. 3 shows the configuration of an apparatus configured to accomplish the semiconductor substrate dividing method of the present invention. In the apparatus shown in the figure, a diced semiconductor wafer 30 bonded to a shrinkable adhesive sheet 23 is housed between two holders 21 and 22 having hollow portions 24 and 26.

In order to create a vacuum inside the hollow portion 24 of the holder 21, a vacuum gauge 26 and an on-off valve 28 for determining the degree of vacuum are connected to the holder 21. In order to make the holder 22 and the inside of the hollow part 26 high pressure, a high pressure needle 27 and its opening/closing valve 2 are used to judge the high pressure level.
9 is connected to the holder 22.

Next, FIG. 4 (&) shows a method for dividing a semiconductor substrate according to the present invention.

This will be explained using (b) and (0).

First, in FIG. 4(&), an adhesive shrink sheet 23 on which a diced semiconductor wafer 3o is adhesively fixed is fixed between an upper holder 21 and a lower holder 22. As shown in FIG. At this time,
Upper holder 21, adhesive shrink sheet 23, lower holder 2
2 is in a state where they are in close contact with each other. Next, in FIG. 4(b), the hollow part 24 of the upper holder 21 is made into a vacuum state under the above conditions, and pressurized gas is introduced into the hollow part 26 of the inferior part holder 22 to make it into a high pressure state. Perform each operation simultaneously. By doing so, the adhesive shrink sheet 2 fixed between the upper holder 21 and the lower holder 22
3 is drawn into the hollow portion 24 of the upper holder 21 due to the pressure difference. At this time, the semiconductor sea urchin . However, in FIG. 4(c), the upper holder 21
A force is generated in the adhesive shrink sheet 23 pulled toward the hollow part 24 to make it into a spherical shape, and as a result, the adhesive shrink sheet 23 maintains its flat shape due to the semiconductor wafer 30 that is adhesively fixed. However, the force generated as described above is applied to the bottom of the groove formed in the semiconductor wafer 30, causing it to crack and be divided into individual semiconductor chips 32. Then, the adhesive shrink sheet 23 is attached to each semiconductor chip 3.
2 and form a spherical shape with a slight interval. After this, the semiconductor chip 3 is removed from the upper holder 21 and the lower holder 22.
2 is removed, and the semiconductor chips 32 are sorted using an expansion machine or the like.

Note that the adhesive shrink sheet 23 may be a film with no air permeability at all, or may be a film with some degree of air permeability. If the adhesive shrink sheet 23 has air permeability, even if the sheet is bent and chips are generated when the semiconductor wafer is divided, the hollow part 26 of the lower holder 22 will be removed from the hollow part of the upper holder 21. A flow of air is generated towards the section 25 , which effectively ejects the debris from the vacuum port 31 of the upper holder 21 .

As is clear from the above explanation, when the semiconductor wafer is divided, the semiconductor wafer surface is in a non-contact state, and the circuit elements formed on the semiconductor chip surface may be damaged or cracked due to the fragmentation of the semiconductor wafer that occurs during the division. It will never occur. Even if a piece of a semiconductor sea urchin occurs, if the adhesive sheet is made breathable, it will be discharged from the vacuum port of the upper holder and will not adhere to the semiconductor chip. There is no short circuit between wiring lines of the formed elements. Moreover, by introducing high temperature pressurized gas into the hollow part of the lower holder, the shrinkability of the adhesive shrink sheet can be suppressed, and the semiconductor wafer can be divided smoothly.

As explained above, the semiconductor substrate dividing method of the present invention can divide semiconductor substrates with a high yield, and has high industrial utility value.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the steps of the manufacturing process of a semiconductor winter board, Figs. 2 (a), (b), and (c) are diagrams showing a conventional method of dividing a semiconductor board, and Fig. 3 is a diagram showing the method of dividing a semiconductor board according to the present invention. Figures 4 (4) and 4 (4) are diagrams illustrating the configuration of an apparatus for carrying out the semiconductor winter board dividing method.
b). (c) is a diagram showing a method of dividing a semiconductor winter plate in an embodiment of the present invention. 21... Upper holder, 22... Lower holder, 23... Adhesive shrink sheet, 3o...
... Semiconductor wafer, 32 ... Semiconductor chip. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 112 Figure 2 ←175-! ! Figure I3

Claims (1)

[Claims] 1. A method for dividing a semiconductor substrate, which comprises dividing the semiconductor substrate by bending an adhesive sheet to which the semiconductor substrate is attached due to a pressure difference.