Reticle transmittance measurement method, and projection exposure method using the same

Patent metadata

Field	Value
Publication number	US-9733567-B2
Application number	US-201514859781-A
Country	US
Kind code	B2
Filing date	Sep 21, 2015
Priority date	Sep 30, 2014
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

When a reticle is first used, the reticle is loaded in a projection exposure device and measured by either oblique measurement and random measurement, thereby avoiding the fear of uneven sampling and determining the reticle transmittance of the entire reticle as the parent population, without increasing the sampling count. The same effect can be obtained by making the measurement spot size, which is fixed in general, variable and by changing the angle of incidence in relation to the measurement spot size.

First claim

What is claimed is:

1. A reticle transmittance measurement method for a projection exposure device configured to project a pattern of a reticle onto a wafer to obtain a given pattern on the wafer,
the reticle transmittance measurement method comprising:
sampling a transmittance of the reticle by measuring the transmittance of the reticle along an oblique route that runs diagonally relative to the reticle, with a sampling pitch being set so as to match with a different pattern of a reticle pattern that has a same repetition pitch, and not to match with a same pattern of the reticle pattern that has the same repetition pitch.

2. A projection exposure method, comprising performing exposure load correction based on a reticle transmittance that is determined by the reticle transmittance measurement method of claim 1 .

3. A projection exposure method according to claim 2 , wherein the exposure load correction comprises at least one of focus correction, lens distortion correction, or magnification correction.

Assignees

• Seiko Instr Inc
• Sii Semiconductor Corp

Inventors

• Murata Michihiro
• Gomi Yutaka

Classifications

• G03F7/70666

  Aerial image, i.e. measuring the image of the patterned exposure light at the image plane of the projection system · CPC title

• G01M11/0285

  by measuring material or chromatic transmission properties (G01M11/0292 takes precedence) · CPC title

• G01N21/956 Primary

  Inspecting patterns on the surface of objects {(contactless testing of electronic circuits G01R31/308; testing currency G07D; manufacturing processes per se of semiconductor devices implementing a measuring step H10P74/20)} · CPC title

• G01N2021/5919

  Determining total density of a zone · CPC title

• G03F7/20 Primary

  Exposure; Apparatus therefor (photographic printing apparatus for making copies G03B27/00) · CPC title