JPH0450733B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an irradiation device that irradiates light along the periphery of a workpiece in a border shape.

[Technical background of the invention and its problems] In the manufacturing process of semiconductor devices, a so-called wafer made of a thin disk-shaped semiconductor member is coated with a photoresist (hereinafter referred to as resist), and then subjected to soft baking, exposure, and development. etc. will be carried out. During this time, the wafer is transported by being accommodated in a carrier as necessary, but after soft baking, the resist around the wafer's periphery peels off due to contact with the carrier, and this often scatters and adheres, resulting in defective products. arise. Particularly in recent years, as the line width of exposure has become narrower and the density of semiconductor devices has increased, the resulting reduction in yield has become a major problem.

As a way to solve this problem, it has been considered to remove the resist in a border-like manner along the periphery of the wafer before soft baking. For example, the resist is removed by spraying a processing liquid for removing the resist onto the peripheral edge of the rotating wafer. However, this method has the disadvantage that it is difficult to remove the resist from the peripheral edge of the so-called orientation flat (hereinafter referred to as orientation flat), which is formed by cutting out a part of the peripheral edge in a straight line. be.
Another possibility is to expose the periphery of the rotating wafer to light and develop and remove it, but like the previous method, this method also has the disadvantage that it is difficult to expose the orientation flat part, and the wafer has an irregularly shaped periphery. There is a need for an irradiation device that can follow the periphery of a workpiece and efficiently irradiate it with light in a border shape.

[Purpose of the invention]

The present invention has been made in order to eliminate the above-mentioned disadvantages, and is an irradiation device that irradiates the workpiece in a border-like manner with good workability even if the peripheral edge of the workpiece has an irregular shape. The purpose is to provide

[Summary of the invention]

The present invention has a light-receiving section that is provided facing a part of the periphery of a workpiece and is formed so as to face the inside and outside of the periphery, and a similar light-emitting section, and that receives light entering from the light-receiving section. An optical system in which the light is emitted from the light emitting part inward by a predetermined distance, and a projection light that is emitted from the opposite surface of the workpiece and is partially blocked by the workpiece and enters the light receiving part. A light source device that emits the projected light, and a moving means that moves the optical system into which the projected light enters relatively along the periphery, and the optical system passes through the outside of the periphery. This is an irradiation device that emits the projected light that has entered the workpiece a predetermined distance inward, and at the same time moves the optical system relatively, thereby always following the periphery and irradiating the workpiece in a border shape.

[Embodiments of the invention]

The details of the present invention will be explained below with reference to the illustrated embodiments. 1 to 3 show a first embodiment, in which 1 is a wafer, and a resist film 3 that is soft-baked after application is attached to the upper surface 2;
Further, an orientation flat 5 formed by cutting out a part of the peripheral edge 4 is provided. In this embodiment, the present invention is applied to removing the resist film 3 at the peripheral edge of the wafer 1 by projecting light in a border pattern along the peripheral edge 4. Reference numeral 11 denotes a flat base, on which a wafer chuck 13 is rotatably supported via a bearing bracket 12. The wafer chuck 13 is composed of a vacuum chuck connected to a vacuum device (not shown), holds the wafer 1 under reduced pressure, and is rotated by a drive mechanism (not shown) provided below the base 11. . Note that the bearing bracket 12, wafer chuck 13, drive mechanism, etc. constitute a moving means 14. Reference numeral 15 denotes a light source device, which consists of a support stand 16 and a light emitter 17 supported by the support stand 16. Although the inside of the light emitter 17 is not shown, it includes a light source such as a light bulb and a condensing optical system. A ribbon-shaped projection light 18 is emitted from the tip of the wafer 1 from the back side of the wafer 1 to the vicinity of the peripheral edge 4 thereof. Reference numeral 20 denotes an optical device, in which an L-shaped first member 22 is attached to a support stand 21 erected on a base 11 with one side thereof facing toward the center of the wafer 1, and the other side parallel to the above-mentioned one side. second to
A member 23 is attached so as to be adjustable in position, and both ends of an optical fiber bundle 25 serving as an optical system 24 are passed through and supported by both members 22 and 23. The optical fiber bundle 25 is composed of a plurality of optical fibers 25a, 25b, . . . 25n, and each optical fiber 25a, . 25n are formed in exactly the same order as viewed from the center of the wafer 1. The lower end portion held by the first member 22 serves as a light receiving portion 26 and faces the light emitter 17, and the lower end portion held by the second member 23 serves as a light emitting portion 27. These light receiving section 26, light emitting section 2
7 is formed on the inside and outside of the peripheral edge 4 with a sufficiently long length so as to straddle the peripheral edge 4, and the projected light 18 from the light projecting body 17 is partially blocked by the wafer 1,
Only the outer projection light 18 enters the light receiving section 26 and is emitted from the light emitting section 27. Therefore, if the second member 23 is moved to bring the emitting section 27 closer to the center of the wafer 1 by a distance f than the light receiving section 26, the area from the periphery 4 inward to the distance f will be irradiated. 31
1 is a side projection device, which includes an optical fiber bundle 32 provided facing the side surface 5 of the wafer 1, a side light projector 34 that sends projection light 33 to the optical fiber bundle 32, and a side light projector 34 erected on a base 11. The support stand 35 supports the body 34. The side light projector 34 has the same configuration as the light projector 17, so a description thereof will be omitted.

Next, the operation of this embodiment will be explained. First, the light emitting part 27 is fixed to the light receiving part 26 so as to protrude inward by a predetermined amount f (the distance in the radial direction for removing the resist film 3). Next, the wafer 1 provided with the resist film 3 is placed substantially concentrically on the wafer chuck 3 and rotated at a low speed. Next, when the light projector 17 and the side light projector 34 are activated, as shown in FIG. The light enters the resist film 3 of the wafer 1 from the light emitting part 27.
Irradiate the top. At this time, the projected light 18 irradiates inward from the peripheral edge 4 up to a distance f, and even if the position and shape of the peripheral edge 4 change due to rotation, for example due to the orientation flat 5 or eccentricity, the peripheral edge 4 always blocks light.
The area between the distance f and the distance f is exposed in a border pattern. At the same time, the resist film 3 on the side surface of the wafer 1 is also exposed by the projected light 33 from the side light projector 34. After the exposure for a predetermined time is completed, the wafer 1 is removed, and the resist film 3 in the exposed area is removed in the next processing step.

Next, FIGS. 4 and 5 show the configuration of the second embodiment, and since only the optical system 24 is different from the first embodiment, this will be explained. In this embodiment, two identical wedge-shaped prisms 41 and 42 are provided as light-receiving sections on the periphery 4 of the wafer 1.
An optical system 45 is formed by a total reflection prism 43 as a light emitting section provided above the prism. The portion of the projected light 18 that is outside the periphery 4 passes through the prisms 41, 42, and is translated inward from the periphery 4 by a distance f as shown in FIG.
The total reflection prism 43 descends again to irradiate the resist film 3. The distance f is adjusted using prisms 41 and 4.
This is done by moving the two relatively.

In the explanation of the first embodiment and the second embodiment, the distance between the light receiving section 26 and the projection section 27 is illustrated in a considerably large size for easy understanding, but in order to maintain sufficient accuracy of the distance f, It is necessary to provide them as close as possible.

〔Effect of the invention〕

As described in detail above, the irradiation device of the present invention is configured such that the light emitting part is shifted inward by a predetermined amount from the periphery of the workpiece with respect to the light receiving part of the optical system, so that the irradiation device is configured such that the light emitting part is shifted inward by a predetermined amount from the periphery of the workpiece. Since the workpiece can be irradiated in a border-shaped manner, the desired irradiation can be performed without any problems even if the peripheral edge is irregular or the workpiece rotates eccentrically. It is something that plays.

In this embodiment, the case of removing a resist film on a wafer has been described as an example, but the present invention is not limited to this, and may be used as an irradiation device for various processing.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the first embodiment of the present invention, and FIG.
The figure is a front view, FIG. 3 is an enlarged cross-sectional view of the main part explaining the irradiation state of the workpiece, FIG. 4 is a front view of the second embodiment of the present invention, and FIG. 5 is an enlarged main part. FIG. 1... Workpiece, 4... Periphery, 14... Moving means, 15... Light source device, 18... Projection light, 24,
45...Optical system, 25...Optical fiber bundle, 26...
...Light receiving section, 27... Light emitting section.

Claims (1)

[Scope of Claims] 1. An irradiation device that irradiates the peripheral edge of a plate-shaped workpiece with light in a border shape, which is provided opposite to one main surface of the workpiece and directs the light to the periphery of the workpiece. A first light projector that projects onto the periphery, and a light projector that is provided on the periphery of the other main surface side of the workpiece and receives light that is not blocked by the workpiece out of the light from the first light projector. a light receiving section, a deflection section that deflects the received light by a predetermined amount inward of the workpiece, and projects the light deflected by the deflection section onto the periphery of the other main surface side of the workpiece. a second light projector that projects light onto the side surface of the workpiece from a direction substantially perpendicular to the direction in which light is projected by the first light projector; 1. An irradiation device comprising a moving means for moving a workpiece along and relative to the circumference thereof. 2. The irradiation device according to claim 1, wherein the optical system includes an optical fiber bundle.