JPH0341716A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the formation of a resist film on the peripheral part of a wafer and the rear surface of the wafer by forming a frame part comprising coarse-oil resin at the peripheral part of the wafer, and applying resist on the surface of the wafer on which the frame part is formed. CONSTITUTION:A resin 12 is injected through a resin injecting port 11 of an top force 9. A frame part 7 comprising a resin is formed in a doughnut shape so as to cover the peripheral part of a wafer 6. Resist 8 which is dropped on the central part spreads in a concentric circle pattern to the peripheral part by centrifugal force when a wafer sucking pipe 1 is rotated. Since the resist 8 at the lower layer stops at the sidewall of the frame part 7, a resist film is not formed at the peripheral part of the wafer. Meanwhile, the resist 8 at the upper layer spreads on the surface of the frame part 7. Since said part is formed with coarse-oil resin 12, however, the resist does not come into contact with the frame part 7 tightly. The resist 8 is repelled and splashed away.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a method of manufacturing a semiconductor device, more specifically, to a method of forming a resist film on a wafer, in which a resist (IFJ) is formed on the periphery of the wafer and on the back surface of the wafer. The purpose of the present invention is to provide a method for forming a resist film that can prevent the formation of a resist film. The method includes a step of applying .

(Industrial Field of Application J) The present invention relates to a method of manufacturing a semiconductor device, and more specifically, to a method of forming a resist 11Δ on a wafer.

[Prior Art] FIGS. 5(a) and 5(b) are perspective views explaining a resist cloth method using a conventional rotary coating device.

The same figure (a) shows the state before the resist t4 cloth, and the symbol I in the figure shows the state before the resist t4 cloth.
2 is a wafer suction tube, 2 is a wafer, and 3 is a resist.

First, after placing the wafer in the suction tube l and fixing it by suction,
When the wafer suction tube 1 is rotated, the resist 3 is transferred to the wafer 2.
Spread evenly over the top.

After that, when the rotation is stopped after a predetermined period of time has elapsed, the same figure (b)
), a thin resist film 3a is formed on the surface of the wafer 2.
is formed.

(The invention attempts to solve this problem!!!fl) However, according to the above-mentioned conventional method, as shown in FIG. 6(a), the wafer 2
The thickness of the resist film 3a becomes thicker in the peripheral area due to the shape effect. Since this variation in film thickness affects the inside of the wafer, when patterning the resist 1I93a,
There is a problem in that defective patterning occurs due to insufficient exposure, leading to a decrease in yield.

Furthermore, during the application of the resist 3, the resist 3 spreads in close contact with the surface of the wafer 2, and the resist 3 wraps around the wafer 2 from the edge to the back surface along the periphery of the wafer 2. Therefore, after patterning the resist 123a, During transportation or processing for moving on to the next process, the resist film 3a remaining in this area comes into contact with a wafer holder and peels off, causing the wafer 2
There is a problem in that it becomes dust and adheres to the surface, causing a decrease in yield.

To solve this problem, the resist film around the wafer is removed. That is, as shown in FIGS. 4(b) and 4(c), resist stripping liquid I is sprayed on the periphery and back surface of the wafer to remove the resist.

In addition, as shown in FIG. 3D, only the peripheral part and the back surface of the resist 1 pattern 3a are exposed and immersed in the developing fi5, thereby removing the resist film 3a in these parts.

However, since it is necessary to carry out this operation every time the resist film is parsed, there is a problem that a large number of man-hours are required and the throughput is reduced.

Therefore, the present invention was created in view of the above-mentioned interprinting problems of the conventional example, and provides a resist I that can prevent the formation of a resist film on the periphery of the wafer and the back surface of the wafer.
The purpose of this paper is to present a method for forming &f.

(Means for Solving Problem Ll!) The above problem consists of a step of forming a frame made of an oleophobic resin around the wafer, and a step of applying a resist to the wafer surface on which the frame is formed. This is achieved by a method of manufacturing a semiconductor device characterized by having the following characteristics.

[For production]

According to the method for manufacturing a semiconductor device of the present invention, since a frame made of an oleophobic resin is formed around the wafer, for example, when a resist is applied using a spin coating device, the lower layer is spread out due to centrifugal force. The resist of 461 is stopped at the resin frame and no resist film is formed around the wafer.On the other hand, the upper layer of resist spreads to the surface of the 461 resin frame, but this part is made of oleophobic resin. , the resist does not come into close contact with the frame and is repelled and scattered from the edge of the wafer.

In this way, first, the resist film is prevented from being formed in the periphery of the wafer where the resist film thickness becomes thinner due to shape effects, so that the resist film thickness is uniform over the entire wafer. Therefore, sufficient exposure is performed over the entire wafer, reducing patterning defects and improving yield.

Secondly, the resist is not 'PGHed' by the frame but is repelled and scattered from the edge of the wafer, so that the resist does not run around the wafer periphery to the back surface of the wafer.

In addition, if applied after the process of high-temperature heat treatment or chemical treatment that burns the resin on the frame, this frame can be used as is during patterning of the resist film without having to remove it. Can be used. This eliminates the need to remove the resist film on the periphery of the wafer and on the back surface each time the resist film is patterned, unlike the conventional method, and it is possible to improve throughput.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1(a) to 1(r) show resist n of examples of the present invention.
FIG. 2 is a diagram illustrating a method of forming No. 2;

Figure (a) is a cross-sectional view of a wafer on which a resist is applied to pattern the interlayer insulation film after depositing interlayer insulation 11Δ (not shown), and figure (b) is a top view of the wafer. . In the figure, 6 is a wafer to which a resist is applied.

First, in order to form a resin frame around the periphery of the wafer 6, the wafer is set in a molding device.

FIG. 2 is a cross-sectional view of such a molding device.
In the figure, 9 is the upper mold, IO is the lower mold, 11 is the resin injection port,
It also works to bleed air. Further, 12 is an injected hydrophobic resin, which is a fluorine-based thermally polymerizable monomer, such as 2.
2.2-) Acrylic resin monomers such as trifluoroethyl methacrylate and trifluoromethyl methacrylate are used. Furthermore, 13 is a suction port for suctioning and fixing the wafer 6.

As shown in the figure, resin is injected from the resin injection port 11 of the upper mold 9!
2 is injected to form a donut-shaped frame 7 made of resin with a thickness of about 5 μm and a width of about 30 mm so as to cover the peripheral area of the wafer 6 (FIGS. 1(c) and (d)). .

Thereafter, the wood j112 is hardened at a temperature of 150°C.

Next, a resist 8 is applied onto the surface of the wafer 6 on which the frame portion 7 is formed using a spin coating apparatus shown in FIG.

That is, as shown in FIG. 3(a), when the wafer suction tube 1 rotates, the resist 8 dropped in the center spreads concentrically around the periphery due to centrifugal force.

Since the lower resist 8 is stopped at the side wall of the frame 7, no resist film is formed around the wafer.
The resist 8 on the dirt floor also spreads over the surface of the frame 7, but since this part is made of the sparsely retractable resin 12, the resist 8 does not come into close contact with the frame 7 but is repelled and blown apart. Therefore, it is possible to suppress the fluctuation of 1I2Iv due to the shape effect of the wafer periphery 8!1, and form a uniform resist 1 8a on the entire wafer, and also to form resist 1 on the edges and back surface of the wafer, unlike the conventional method. 8 does not go around.

After that, after rotating for a predetermined amount of time, the rotation is stopped (third
Figure (b)).

Next, the resist is hardened by baking to form a resist film 8a (FIG. 1(e), H).

Next, after exposure using a reduction projection exposure device or the like, development is performed to form Resist II! ! ! Perform patterning of 8a, at this time resist with uniform W/i thickness over the entire wafer) 1!8
Since a is formed, the entire wafer is exposed to light as necessary and sufficient. Thereby, defective patterning can be reduced and yield can be improved.

Subsequently, the wafer 6 is placed in a reaction chamber of a sputter etching apparatus, and the small area between the eyebrows is etched using CF4 gas.

At this time, since the resist film 8a is not formed on the wafer 6@ part or the back surface, dust may be generated due to peeling of the resist film 8a due to contact between the wafer 6 and a wafer holder, etc., during transportation or processing of the wafer 6. can be prevented from occurring. Further, the resin frame portion 7 is not etched by CF or gas.

Thereafter, the resist film 8a is removed using a resist stripping solution such as xylene or orthodichlorobenzene. At this time as well, the resin frame 7 is not exposed to the resist stripping solution, so that the frame 7 can be used as is when patterning the next resist film.

In this way, patterning of the resist 1 can be performed many times with the frame portion 7 formed as it is.
Unlike the conventional method, there is no reduction in throughput.

Finally, the frame portion 7 is removed by dry etching using oxygen as a reaction gas.

Next, another embodiment of the present invention will be described with reference to FIG. 4.

This figure is a top view of a wafer showing the shape of a frame made of resin of a loose drawing 111- according to another embodiment of the present invention, in which the frame 7a is formed to match the shape of the chip.

It goes without saying that even in this case, the same effects as those of the above-mentioned embodiments can be obtained. Note that the reference numeral 6a in the figure indicates a wafer.

〔Effect of the invention〕

As described above, according to the manufacturing method of the present invention, since the frame made of oleophobic resin is formed around the wafer, the formation of the resist 119 on the wafer periphery and the back surface of the wafer is prevented. It can be prevented.

Therefore, it is possible to prevent dust from being generated due to resist peeling due to contact with the wafer while holding the wafer.

Thereby, it is possible to improve the yield of semiconductor devices.

Further, after forming the frame portion, the frame portion can be used as many times as desired during patterning of the resist film. Therefore, the throughput does not decrease as in the conventional case.

[Brief explanation of drawings]

1(a) to (f) are diagrams explaining the manufacturing method of the embodiment of the present invention; FIG. 2 is a sectional view of a molding device used for forming the frame portion of the embodiment of the present invention; Figures (a) and (b) are perspective views illustrating a resist cloth according to an embodiment of the present invention; Figure 4 is a top view of a wafer showing the shape of a frame according to another embodiment of the present invention; 5(a) and 5(b) are perspective views illustrating conventional resist coating, and FIG. 6 is a perspective view illustrating conventional resist coating. (Explanation of symbols) l...Wafer suction tube, 2.6.6a...Wafer, 3.8...Resist, 3a, 8a...Resist film, 7.7a...Frame part, 9 ...Upper mold, 10...Lower mold, 11...Resin injection port, 12...Resin, 13...Suction port. A cross-sectional diagram explaining the problems of the conventional example.

Claims (1)

[Claims] A semiconductor device comprising the steps of: forming a frame made of an oleophobic resin around a wafer; and applying a resist to the wafer surface on which the frame is formed. Production method.