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ABSTRACTS ON MICROELECTRONICS
C-MOS holds down parts count for digital clocks. SUKHENDU DAS. Electronics, June 7 (1973), p. 118. Quartz-crystal clock generators are usually employed only when high frequency stability is required, because "the crystal and other closetolerance components necessary for the circuit are expensive. However, for most digital systems, a clock generator having an over-all frequency accuracy of just 0.1 per cent provides sufficient immunity against changes in supply voltage and temperature. Precision comparator circuit satifies L.S.I. testing needs. GEORGE NIU. Electronics, April 26 (1973), p. 122. Testing large-scale integrated-logic arrays requires an analog comparator with characteristics that cannot be found in an offthe-shelf unit. To perform state-of-the art LCI testing, you must build your own comparator. The modern LSI functional-testing system needs lowcost comparators because many of them must be used in any test system. Generally, two comparators are required for each pin of the device under test. For example, in a 240-pin system, there must be 480 comparators. Another consideration is miniaturization--a basic requirement for an LSI test-system comparator that allows it to be mounted as close as possible to the device under test. Short lead lengths are a must to minimize the capacitance on the output pins of the unit being tested. High capacitance will produce discharge currents, causing spikes or noise on the system ground and producing faulty readings. A bipolar control storage memory-design-considerations and test problems. THOMASMITCHELL and GERALD KANE. Solid St. Technol., March (1973), p. 41. The bipolar RAM semiconductor memory chip used in the control storage memory of the UNIVAC 9700 computing system is described. A brief discussion of both the system design and system reliability considerations is presented. Incoming inspection test philosophy is discussed as well as several problems associated with the use of bipolar semiconductor memory. The Intel 1103 : the M O S memory that defied cores. GEORGE SIDERIS.Electronics, April 26 (1973), p. 108. A young company banked on a silicon-gate p-channel dynamic MOS randomaccess memory to replace cores in mainframes: a Honeywell team aided in the design, which has become an industry standard. MOS circuits in industrial and domestric control. M. J. CHAPMAN. Electron. Power, June (1973), p. 238. The advent of large-scale integrated circuits using MOS technology has
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meant that complex control functions for domestic appliances and industrial equipment can be easily and economically realised. A fast logic gate for large scale integration. EEN, June (1973), p. 65. When selecting a suitable gate for high speed LSI logic arrays factors such as the packing density and ease of mask layout must be considered in addition to the electrical performance. These considerations led to gate designs having a simple configuration and low power dissipation which result from the use of a low standing current and low supply voltage; this is possible when the gate is designed with a small logic swing. Two gates which fulfil these requirements and which have received much attention are the long tail pair gate (LTP) and the positive feedback gate (PF). Family of inductorless oscillators derived from gyrator circuits. A. J. GREAVES and J. M, ROLLETT. Post Office Engng. Dept. Res. Station Dollis Hill U.K. NL1-7738-2RES-DEPT-RPT-290, 6 (1972). A family of inductorless oscillators derived from gyrator circuits is described. The oscillators each employ two differential-input integratedcircuit operational amplifiers, together with resistors and capacitors. Alternative methods of providing regenerative feedback are outlined and amplitude stabilization is achieved by adding diodes. One of the oscillators was studied in detail and it was found that a sinusoidal output signal with amplitude greater than one volt peak-to-peak and harmonic distortion less than 0.1 per cent was readily obtainable over the frequency range of 0.1 100 kHz. M O S system reduces exhaust pollution. M. WILLIAMS. Electron. Power, June (1973), p. 264. It is possible to minimize exhaust pollution from automobiles by precise control of the fuel input to the engine. One way of achieving such control is by using a digital memory system using metaloxide-semiconductor (MOS) integrated circuits. Data communications and the minicomputer. JAMESPISAICK EElS stems Engn 9 Today. February (1973), p. 50. Adaptability at the computer/communications interface has always been attractive, but expensive, feature. The new MOS/LSI devices are making that cost a lot more affordable. 1C timers make the most of delay. LUCINDA MATTERA. Electronics, June 21 (1973), p. 142. Applications base for lowcost integrated timing circuits continues to broaden as new devices offer the user additional versatility.
7. SEMICONDUCTOR INTEGRATED CIRCUITS, DEVICES AND MATERIALS High-resolution SEM observation of semiconductor device cross-sec/ions. E. S. MEIERAN and T. I. KAMINS. Solid St. Electron. 16 (1973), p. 545. This paper describes a method for preparing cross-sections of semiconductor devices for high-resolution examination in a scanning electron micro-
scope. Multiple layers of polycrystalline silicon are deposited on the surface of interest in order to preserve surface details. The sample is then carefully sectioned using normal metallographic procedure and is highly etched to bring out structural detail. Three applications of the method are given: structural