Production of semiconductor modules by a photo-resist technique with holographic projection of etching patterns

Abstract

Abstract IN THE PHOTO-RESIST TECHNIQUE OF PRODUCING INTEGRATED CIRCUITS AND OTHER SEMICONDUCTOR MODULES, A PLURALITY OF HOLOGRAMS OF RESPECTIVELY DIFFERENT ETCHING PATTERNS ARE SEQUENTIALLY PROJECTED ONTO A LIGHT-SENSITIVE COATING OF A SEMICONDUCTOR SUBSTRATE, ANOTHER FABRICATING STEP BEING PERFORMED AFTER PHOTOGRAPHIC DEVELOPMENT OF EACH ETCHING PATTERN THUS PRODUCED. AT LEAST THREE REGISTER MARKS ARE HOLOGRAPHICALLY PROJECTED TOGETHER WITH EACH OF THE LIKEWISE HOLOGRAPHICALLY PROJECTED DIFFERENT ETCHING PATTERNS APPERTAINING TO ONE AND THE SAME MODULE BEING PRODUCED. RELATIVE TO EVERY ONE OF THE DIFFERENT ETCHING PATTERNS, THE REGISTER MARKS HAVE THE SAME SHAPE AND THE POSITION; AND AFTER THE FIRST EXPOSING AND ETCHING THESE MARKS APPEAR ON THE SUBSTRATE SURFACE AS DISTINCT REFLECTIVE AREAS. DURING EACH SUBSEQUENT EXPOSING, THE REFLECTIVE REGISTER MARKS ON THE SUBSTRATE ARE PLACED IN THE REGISTRY WITH THE SPATIAL IMAGE OF THE REGISTER MARKS THAT, DUE TO THE RECONSTRUCTED REGISTER-MARK WAVE, APPEAR WHEN EACH OF THE OTHER PATTERNS IS BEING PRODUCED. THE ACCURATE REGISTERING IS DONE BY ADJUSTING TO A MAXIMAL VALUE THE SPACING OF THE FRINGE STRIPES OF THE INTERFERENCE FIELD FORMED BY THE REGISTER-MARK WAVE WHICH IS REFLECTED FROM THE REGISTER MARKS ON THE SUBSTRATE ON THE ONE HAND AND BY THE COMPARISON WAVE WHICH SIMULATNEOUSLY RESULTS FROM THE HOLOGRAM REPRODUCTION AND WHICH CONTAINS A VIRTUAL IMAGE OF THE REGISTER MARKS.

Inventors

• 👤 D Ross
• 👤 H Kiemle

Bibliographic Details