JPH065508A - Manufacture equipment of semiconductor - Google Patents

Abstract

PURPOSE:To improve the yield of a semiconductor element by a method wherein the whole area on a wafer having a part wherefrom a good element can be obtained is exposed by one shot and a part in the shot wherefrom the good element cannot be obtained is not exposed, when a plurality of patterns are exposed at once by one shot by a stepper or the like. CONSTITUTION:An exposure shield cover 109 is fitted to a part outside the limit on a wafer 105 on a stepper device inside of which a good element can be obtained. Thereby shot exposure is conducted for the whole part on the wafer 105 which needs to be exposed, and an area not to be exposed is prepared only in the outer peripheral end of the wafer 105 which is not desired to be exposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus for exposing and transferring a pattern of a semiconductor integrated circuit or the like onto a photosensitive organic film on a semiconductor substrate (hereinafter referred to as a wafer).

[0002]

2. Description of the Related Art In recent years, semiconductor integrated circuits have been highly integrated and miniaturized, and high-density memory circuit devices called VLSIs have been manufactured. In order to form a VLSI circuit pattern on a wafer, it is necessary to form a fine pattern accurately. Therefore, a reduction projection exposure apparatus, so-called stepper is used.

FIG. 3 is a basic configuration diagram of an example of a conventional stepper. A stage 107 that is movable in the X-Y2 directions is installed on the earthquake-proof table 108. The light 100 generated from the light source 101 becomes a parallel light flux by the condenser lens 102, and passes through the reticle 103 in which the semiconductor integrated circuit pattern is magnified n times the actual size. The reticle image is reduced to 1 / n, that is, an actual size by the reduction projection lens 104, and image-wise exposed on the wafer 105.

By the way, the area which can be exposed at one time by using the reduction projection lens 104 is usually about 5 to 15 mm square,
The wafer used for this is 100-200 m in diameter
It is impossible to expose the entire surface of the wafer at a time in the range of m. Therefore, after exposing the area for one shot, the stage 107 is moved, the other area is exposed, and the entire surface of the wafer is exposed by repeating the movement and exposure of the stage (step-and-repeat exposure). .

When the area of the pattern for one semiconductor integrated circuit is 1 / m with respect to the exposure area for one shot, a reticle having a pattern containing m semiconductor integrated circuits for one shot is used. However, a method of reducing the number of shots of the exposure number of the stepper is also used.

[0006]

In this conventional stepper, when a pattern of one semiconductor integrated circuit is exposed for one shot (hereinafter referred to as "single-sided exposure"), only a portion of the semiconductor integrated circuit which can be taken is shot. If, is hit, only the area of the exposure unit 201 is exposed as shown in the plan view of the wafer in FIG. When the area of the exposure unit 203 is exposed in order to increase the number of effective semiconductor integrated circuits, multiple-sided exposure (FIG. 2 shows an example of six-sided attachment)
Therefore, even the exposure unit 202 is exposed.

When the wafer outer peripheral edge 204 is also exposed, in the etching process of the next processing step, the portion patterned at the outermost peripheral edge is likely to cause an abnormality in the etching, and therefore shots are prohibited. There is. For this reason, in the case of performing multiple exposure, there is a drawback in that shots cannot be shot even though there is an exposed portion capable of taking an effective semiconductor integrated circuit.

In order to remove the photo-sensitive organic film outside the limit line 205 where the non-defective element on the outer periphery of the wafer can be taken, a solvent is used after applying the photo-sensitive organic film. Since it may contribute to the etching reaction in the next etching process, it also becomes a problem to remove it, and the photosensitive organic film must be left.

[0009]

The stepper of the present invention comprises:
An exposure shield cover is provided on the peripheral edge of the wafer so that the area outside the limit line on which the non-defective device on the wafer can be taken is not exposed.

[0010]

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

FIG. 1 is a block diagram of an embodiment of the present invention.
Stage 1 that can move in the X-Y2 directions on the earthquake-proof table 108
07 is installed. Light 10 emitted from the light source 101
0 becomes a parallel light flux by the condenser lens 102 and passes through the reticle 103 which is enlarged by n times the actual size of the semiconductor integrated circuit pattern. The reticle image is reduced to 1 / n, that is, the actual size by the reduction projection lens 104, and image-wise exposed on the wafer 105.

By the way, the area which can be exposed at one time using the reduction projection lens 104 is usually 5 to 15 mm square, and the wafer used for it has a diameter of about 100 to 200 mm, and it is impossible to expose the entire surface of the wafer at one time. Is. Therefore, after exposing the area for one shot, the stage 107 is moved, the other areas are exposed, and the movement and exposure of the stage are repeated again to expose the entire surface of the wafer.

The exposure shield cover 109 is a wafer outer peripheral edge 2 outside the limit line 205 where the non-defective element of FIG. 2 can be taken.
It is made so that the 04 side is not exposed to ultraviolet light,
The stage 107 is fixed during exposure. Therefore, when the reticle 103 with six impositions is used for exposure at a position including the exposure unit 202 and the exposure unit 203, the exposure unit 20
The semiconductor integrated circuit can be patterned at the position 3 and the outside of the limit line 205 where the non-defective element at the position of the exposure portion 203 can be taken is not exposed.

Therefore, even if the entire area of the exposure shot area 206 (6 impositions) is exposed, since the area outside the limit line 205 where the non-defective element can be taken is not exposed, the photo-sensitive organic film remains and the next step The etching process can be normally performed.

[0015]

As described above, according to the present invention, the exposure shield is attached to the outside of the limit line where a good element of the semiconductor integrated circuit can be taken so that the photosensitive organic film is not exposed. When performing, it becomes possible to perform exposure on all areas where good elements can be obtained,
Moreover, there is an effect that the next etching process can be stably performed. Furthermore, since the number of semiconductor integrated circuits that become non-defective elements increases, it has the effect of increasing the yield of semiconductor integrated circuits on one wafer.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a plan view of a wafer for explaining how to hit a shot in multiple-sided exposure.

FIG. 3 is a configuration diagram of a conventional device.

[Explanation of reference signs] 100 ultraviolet light 101 light source 102 condenser lens 103 reticle 104 reduction projection lens 105 wafer 106 wafer stage 107 stage 108 seismic isolation table 109 exposure shield cover 201 exposure section 202 exposure section 203 exposure section 204 wafer outer edge 205 Limitable line 206 Exposure shot area

Claims (1)

[Claims] 1. In a semiconductor manufacturing apparatus for performing projection exposure of a pattern formed on a reticle by ultraviolet light onto a wafer coated with a photosensitive organic film, in order to form an unexposed portion on the outermost peripheral portion of the wafer. The semiconductor manufacturing apparatus, which is provided with the exposure shielding cover.