Paper-tape-controlled electron probe resist exposure and direct metallic deposition

Computer-aided design techniques are now used extensively for the production of masks in the microelectronic industries. In these methods the microcircuit patterns are broken down into simpler component parts, such as rectangles, whose co-ordinates are punched onto paper tape. A logic system has been developed to control an electron probe from coordinates read in on paper tape. Successive rectangles specified on the tape are scanned by the probe on the specimen, exposing an electron-sensitive material. A microcircuit pattern is thus built up from these basic rectangular elements. The use of an electron probe allows the generation of patterns with submicron dimensions within a reasonable time. The system outlined above has been used to produce microcircuit patterns using two techniques. In one, electron-sensitive resist is used to define a pattern etched in underlying material; in the other, metallic patterns are deposited directly by the decomposition of a metallic compound.