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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.

A convenient form of graph paper is described that allows the frequency constant (f c ) and the MTF index ( n ) of many devices to be easily determined.

We propose a new kind of cathode-ray tube, namely, the thermal-transmission cathode-ray tube (TTCRT). In the TTCRT the electron beam focused to a small spot is called upon to heat in sequence small elements of a matrix that constitutes the faceplate of the tube. A heat-sensitive or thermal paper passed across the screen and maintained in contact with it, and outside the tube, will record characters and dot patterns generated through suitable two-dimensional deflection of the electron beam. We give a description of the main parameters regulating the performance of the TTCRT.