Patent · US Expired

Exposure method and exposure apparatus

US4974018A · kind A · utility

16Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1988
Grant dateNov 27, 1990
Priority date
Expiry dateDec 23, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70883
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The invention deals with an exposure apparatus which detects environmental conditions such as atmospheric pressure, temperature and humidity in which the exposure apparatus is placed, and which maintains the projected magnification constant at all times based upon the detected values, so that the pattern can be reproduced precisely. Concretely, the apparatus comprises a detector to detect at least one of the tube temperature of the optical projecting system, humidity or atmospheric pressure near the optical system, and a control unit which controls optical characteristics based upon the signals detected by the detector. Namely, the control unit adjusts the optical characteristics depending upon the environmental conditions thereby to adjust variation in the projecting magnification and/or variation in the focal position. Thus, variation in the optical characteristics is adjusted to transfer the pattern maintaining high precision.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.