Method of producing master and working pattern plates for etching and

Abstract

In a method of producing master and working pattern plates for etching to form a shadow mask, various etching patterns are needed, for example, a pattern of predetermined holes for passing electron beams, a pattern of register marks necessary for accurate alignment of a pair of obverse and reverse working pattern plates, and a frame pattern for cutting off a portion which is to be a shadow mask from a metal plate by etching process. These individual pattern data required for etching are first prepared and then subjected to logical operation to prepare data representative of a synthetic pattern which is to be finally drawn on a photosensitive plate. Then, all the necessary patterns, including the frame pattern, register mark pattern, hole pattern, etc., are formed by continuous and collective exposure process by use of the synthetic pattern data, thereby eliminating the need for the step of aligning the individual patterns by a manual operation, which has heretofore been essential for multiple exposure, and thus solving not only the conventional problems in terms of both quality and process but also the problem attributable to the positioning accuracy of a photolithographic apparatus in which control is effected by a laser interferometric measuring device in an environment other than a vacuum.