JPH04282822A - Stage for contraction projection type exposure device - Google Patents

Abstract

PURPOSE:To prevent positional deviation of a wafer due to loading. CONSTITUTION:A light source 1 for irradiating an orientation flat part 8 of a wafer 4 with a light through a half mirror 2, and an imaging unit 5 for inputting a reflected light of the light and imaging the part 8, are provided in a stage body 7, and the direction of the part 8 is inspected.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage of a reduction projection type exposure apparatus (hereinafter referred to as a stepper) used in an alignment exposure step after coating a photoresist during the manufacturing process of semiconductor devices.

0002

[Prior Art] Generally, in the loading operation of loading a wafer onto a stage in a stepper, the wafer is temporarily loaded on a pre-alignment stage placed before being transferred to this stage, and the outer shape and orientation flat part of the wafer is detected. However, rough positioning was performed by changing the wafer to a desired orientation. Then, this wafer was transferred from the pre-alignment stage to the stage. When exposing these wafers, the wafer position and orientation on the stage were sometimes not checked.

0003

[Problems to be Solved by the Invention] When loading a wafer onto the stage in the conventional stepper described above, the wafer position and orientation are set and transferred only by alignment work on the pre-alignment stage, so it is difficult to transfer the wafer. If a mechanical or electrical problem occurs in the wafer transport mechanism, it becomes difficult to transfer the wafer to the stage while maintaining the position and orientation of the wafer. In addition, the positioning error on the pre-alignment stage and the error that occurs during transportation from the pre-alignment stage section to the stage are added together, increasing the positional error of the wafer on the stage, causing defective exposure patterns, and reducing the yield of semiconductor devices. There is a problem in that it significantly reduces the

SUMMARY OF THE INVENTION An object of the present invention is to provide a stage on which a wafer can be placed with high accuracy in order to solve this problem.

[0005]

[Means for Solving the Problems] The stage of the reduction projection type exposure apparatus of the present invention is such that, in the stage of the reduction projection type exposure apparatus on which a resist-coated wafer is placed, a half mirror is provided to the orientation flat part of the wafer. a light source unit that projects light, an imaging unit that receives light reflected from the orientation flat unit, and a cut filter that removes light having a wavelength to which the resist is sensitive from among the light from the light source unit. ing.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings. 1(a) and (b) are a plan view and an AA sectional view showing a stage in a stepper according to an embodiment of the present invention, and FIG.
FIGS. 2A and 2B are observation diagrams of an imaging unit for explaining the operation of the stage in FIG. 1. FIGS. As shown in FIG. 1, the stage in this stepper includes a light source section 1 that irradiates light onto an orientation flat section 8 of a wafer 4 placed on a stage body 7 via a half mirror 2, and a light source section 1 that irradiates light from the orientation flat section. An imaging section 5 that receives light through the half mirror 2, a data processing section 6 that processes the image signal of the imaging section 5, and a cut filter that removes the light from the light source section 1 that exposes the resist. 3.

Next, the operation of this stage will be explained. First, the wafer 4 is transferred to the stage body 7 from the pre-alignment stage. Next, light is projected from the light source section 1. This light passes through the half mirror 2, unnecessary light is removed by the cut filter 3, and the orientation flat portion 8 is irradiated with the excluded light. The light reflected from the orientation section 8 enters the imaging section 5. Next, the image signal from the imaging section 5 is processed by the data processing section 6, and the pattern shown in FIG. 2 is displayed on the display section.

If the orientation flat portion imaged in this manner is parallel to the reference line 9, as shown in FIG. 2(a), it is determined to be normal. In addition, as shown in FIG. 2(b), if it is not parallel to the reference line 9, it is considered abnormal;
Correct by rotating stage 7.

[0009]

As explained above, the present invention can inspect the inclination of the orientation flat part of the wafer transferred onto the stage by providing a means for imaging the orientation flat part of the wafer, which improves the accuracy of the transfer. This has the effect of providing a stage on which a wafer can be placed accurately without causing any deviation.

[Brief explanation of the drawing]

1A is a plan view and FIG. 1B is an AA sectional view showing a stage of a reduction projection type exposure apparatus in an embodiment of the present invention.

FIG. 2 is an observation diagram of an imaging unit for explaining the operation of the stage in FIG. 1;

[Explanation of symbols]

1 Light source section 2 Half mirror 3 Cut filter 4 Wafer 5 Imaging section 6 Data processing section 7 Stage body

Claims (1)

[Claims] 1. A stage of a reduction projection type exposure apparatus on which a resist-coated wafer is placed, comprising: a light source unit that projects light onto an orientation flat portion of the wafer via a half mirror; and a light source unit that projects light from the orientation flat portion. 1. A stage of a reduction projection type exposure apparatus, comprising: an imaging section that receives light; and a cut filter that removes light having a wavelength to which the resist is sensitive from among the light from the light source section.