JPH0476916A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To improve productivity and quality with the steps of resist coating and peeling cut down and residuals of resist and chemicals eliminated by sticking a polymer resin film directly to a substrate without use of resist film. CONSTITUTION:The surface of a semiconductor substrate 1 is stuck as a first polymer resin film 2 entirely with a rubbery high polymer resin tape 2 slightly extendable and back-coated with adhesive, and the tape is cut on the substrate 1 side. Next, an excel coat liquid of vinyl chloride that is a second polymer resin is applied by covering the edge side face of the substrate 1 and the tape 2 and naturally dried to volatilize flux, thereby forming a vinyl chloride film 3. Then, the substrate 1 is ground and polished in three stages using a polisher of semiconductor substrate back. The polished substrate 1 rid of the tape 2 by peeling together with the film 3. Use of no resist film like this prevents residuals of resist peeling liquid and deposits of resist and contribute improvement in productivity and quality with the surface kept clean.

Description

Detailed Description of the Invention [Summary] The present invention relates to a method for manufacturing a semiconductor device, and in particular to a method for polishing a semiconductor substrate. a step of pasting a molecular resin film;
a step of drying to form a second polymer resin film, then a step of polishing the back surface of the semiconductor substrate to a certain thickness, and a step of drying the second polymer resin film and the first polymer resin film on the surface of the semiconductor substrate.
The method is configured to include a step of simultaneously peeling off and removing the polymer resin film.

[Industrial application field]

The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for polishing a semiconductor substrate.

The current semiconductor substrate grinding process is long and has problems such as when removing the resist used as a mask with a special solution, the resist remains on the surface of the semiconductor substrate, or the resist stripping solution remains on the surface. A solution to this problem is necessary.

[Conventional technology] Figure 1 is an explanatory diagram of a conventional example.

In the figure, 21 is a semiconductor substrate, 22 is a resist film 23
is a polymer resin film.

In the conventional semiconductor substrate grinding process, in order to prevent the surface of the substrate on which semiconductor elements are formed from being damaged during the grinding process, a thick resist film is applied and ICROSS tape made of a polymer resin film is pasted on top of the resist film. The back was being ground.

This method requires a long process of applying the resist, drying it, and peeling off the resist film after grinding, and also has the disadvantages that small pieces of the resist remain without being removed, and that the residue of the resist stripping solution may cause unevenness on the surface of the semiconductor substrate. There were many problems that remained.

(Problems to be Solved by the Invention) Therefore, in the conventional process, resist coating and stripping exist as independent steps, the steps are long, and there are problems in that residues of the resist and stripping solution remain.

In view of the above points, the present invention solves these drawbacks, and
The object of the present invention is to provide a method that shortens the process of grinding a semiconductor substrate and eliminates various surface residues.

[Means to solve the problem]

FIG. 1 is an explanatory diagram of the principle of the present invention and a schematic cross-sectional view of the process order of back polishing of a semiconductor substrate.

In the figure, 1 is a semiconductor substrate, 2 is a first polymer resin film, 3 is a second polymer resin film, 4 is a dicing line groove, 5 is a gap, 6 is a ground surface, and 7 is a polished surface. .

In the present invention, in order to solve the above-mentioned problems, a rubbery and somewhat extensible first polymer resin film, for example, a Microstave, is directly attached to the element surface on a semiconductor substrate through two dicing line grooves. In order to prevent grinding fluid such as water from entering from the periphery of the semiconductor substrate, a second layer of vinyl chloride gate is installed.
By applying, for example, an Excel coat solution containing a polymer resin in a solvent, no resist is used, i.e., the process of applying and peeling off a resist film is eliminated, and the generation of residues such as resist is prevented. do.

That is, one object of the present invention is the process of attaching a first polymer resin film 2 to the surface of a semiconductor substrate 1, as shown in FIG. 1 and the first polymer resin film 2.

After that, a second polymer resin coating solution is applied and dried to form a second polymer resin film 3, as shown in FIG.
), the step of polishing the back surface of the semiconductor substrate 1 to a certain thickness and simultaneously peeling off and removing the second polymer resin film 3 and the first polymer resin film 2 on the surface of the semiconductor substrate 1 This is achieved by including the steps.

[Function] In the present invention, a polymer resin film is attached directly to the substrate without using a resist film, so the steps of resist application and peeling are reduced, and there is no resist or chemical residue.

〔Example〕

FIG. 2 is a schematic cross-sectional view of the steps of polishing the back surface of a semiconductor substrate according to an embodiment of the present invention. FIG. 3 is a perspective view of a semiconductor substrate back surface polishing apparatus.

In the figure, 1 is a semiconductor substrate, 2 is a first polymer resin film, 3 is a second polymer resin film, 4 is a dicing line groove,
5 is a gap, 6 is a grinding surface, 7 is a polishing surface, 8 is a first wheel, and 9 is a second wheel.

10 is the third wheel, 11 is the first column, 12
14 is the second column, 13 is the third column, 14 is the electric heater 115 is the substrate loading arm, 16 is the adjustment arm 17 is the grinding table, 18 is the substrate removal arm, 19 is the control table, and 20 is the display panel. be.

An embodiment of the present invention will be described.

First, as shown in FIG. 1(a), a semiconductor substrate 1 having a diameter of 150 mm has elements formed on one surface thereof.

A first polymer resin film 2 made of a rubber-based material with some extensibility was formed on the surface of a silicon wafer having a thickness of about 625 μm. A 50 μm thick ICROS tape coated with adhesive on the back side is pasted on the entire surface of the wafer, and the tape is cut on the side of the wafer.

Next, as shown in FIG. 1(b), about 1 coat of Excel coating solution of vinyl chloride, which is a second polymer resin, is applied using a spinner to cover the end side surface of the wafer 1 and the ICROS tape 2.
Apply to a thickness of 0 μm, dry naturally to evaporate the solvent, and
Forms a vinyl chloride film.

Thereafter, as shown in FIG. 1C, the wafer 1 is ground and polished in three stages using the semiconductor substrate back polishing apparatus shown in a perspective view in FIG.

In the polishing apparatus, as shown in a perspective view in FIG.
Attach it to the grinding table and fix it by vacuum suction. The polishing table can be loaded with 150 mm diameter wafers.

The device is provided with three columns from a first column 11 to a third column 13, and each column is equipped with a rotating steel wheel. The tip of the wheel is embedded with fine grains of industrial diamond of different grain sizes, and the grain size becomes finer from the first to the third wheel.

While rotating at 1.500 rpm, the wheel sequentially grinds the wafer 1 on the slowly rotating grinding table 17 starting from the end.

As shown in FIG. 2(a), the wafer 1 is roughly ground with the first wheel 8 to a thickness of 540 μm.

Next, as shown in FIG. 2(b), the second wheel 9 is used to perform medium cutting to a thickness of 510 μm. Furthermore, Figure 2 (
As shown in c), finish cutting is performed using the third wheel 10 to cut down to 500 μm.

The total grinding time is 5 to 6 minutes, and one wafer is finished, and the wafer 1 is automatically sucked by the substrate removal arm 18 and placed in the Univac set.

After the back side of the wafer has been ground, the back side of the wafer is lightly etched for about 30 seconds using an etching solution of fluoronitric acid.

The wafer 1 is polished to a thickness of 490 μm.

The wafer that has been polished is shown in Figure 1 (d)! : As shown, peel off the ICROS tape 2 along with the EXCEL coat film 3 on it and remove it.

Since no resist film was used on the polished wafer in this manner, it was possible to maintain a clean surface without any residue of the resist stripping solution or adhesion of resist.

[Effects of the Invention] As described above, the present invention reduces the resist peeling process and eliminates resist and chemical residues, which greatly contributes to improved productivity and improved quality.

Figure 3 shows wafer back polishing equipment Figure 4 is an explanatory diagram of the conventional example. It is.

In fig.

] is a semiconductor substrate, and 2 is a first polymer resin film.

3 is the second polymer resin film 4, the dicing line groove 5 is the gap, 6 is the grinding surface 7 is the polishing surface 1, 8 is the first wheel 9 is the second wheel, 10 is the third wheel 11 is the first column,
12 is a second column 13 is a third column, 14 is an electric heater 15 is a substrate loading arm, and 16 is an adjustment arm.

17 is the grinding chiffle, 18 is the board removal arm 19 is the control chifur, and 20 is the display panel.

[Brief explanation of drawings]

Fig. 1 is a schematic sectional view of the process order of one embodiment of the present invention. Fig. 2 is a schematic sectional view of the process order of wafer polishing (d). ! iI Human cross section Figure 1 Figure 1 Figure 3

Claims (1)

[Claims] A step of pasting a first polymer resin film (2) on the surface of a semiconductor substrate (1), and an end side surface of the semiconductor substrate (1) and the first polymer resin film (2). a step of coating the semiconductor substrate (1) with a second polymer resin coating solution and drying it to form a second polymer resin film (3); It is characterized by comprising the step of polishing to a thickness, and the step of simultaneously peeling and removing the second polymer resin film (3) and the first polymer resin film (2) on the surface of the semiconductor substrate (1). A method for manufacturing a semiconductor device.