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412
WORLD
ABSTRACTS
ON
MICROELECTRONICS
AND
RELIABILITY
and digital signals continue to increase, they become increasingly difficult to measure. One solution is to build a frequency counter that uses high-speed, emitter-coupled logic (ECL) in the front end and TTL ICs in the counter and timebase chain. If constructed properly, such a counter can measure frequencies in excess of 500 MHz.
of power-supply voltages (3-15 V). In addition, because of its high MOS input impedance, the flip-flop allows very large resistance and capacitance values to be used. For instance, a gated oscillator circuit containing 1-Mf~ resistors and 500-picofarad capacitors will have an input period of 20 min.
Touchless wafer handling. DONALD P. BAUMANN. Solid St. Technol., March (1973), p. 45. Semiconductor wafer processing is discussed with emphasis on wafer handling methods, it is suggested that the increasing high damage rate (and its critical cost) due to "manhandling" of wafers can be reversed by moving them on a linear dynamic air bearing. This appears to be the next step after flip-transferrable carriers. The t :chnique has been applied successfully to at least half a dozen common processing operators by both large and small manufacturers. The system is discussed in detail including comparisons and compatibility with other handling methods, costs, conversion from hand processing, and impact on the industry.
Maskentedmik fdr Integrierte Schaltkreise. DIETER WOLF. Rad. Mentor Electronic 39, No. 6, June (1973), p. 240. (In German). Cover feature, technology of the masks for integrated circuits. The lay-out for an IC is normally done in an enlarged scale of 10: l, 100: l, or 400: 1. This work is now computer-aided design. The masks can be drawn or cut, both methods have their advantages and their drawbacks. The different techniques are explained and possibilities for more rationalization are discussed. The six parts of the cover are the masks for the buried layer, the base diffusion, and the contact windows on the left from top to b o t t o m - - t h e separation, the emitter diffusion, and the aluminium conductors on the right from top to bottom.
Gold-flee film cuts LSI package cost. STEPHEN E. GROSSMAN. Electronics. May 10 (1973), p. 121. Palladium silver metalization, familiar to hybrid-circuit designers, now offers cost savings of 20 50 per cent to monolithic-device makers.
Plasma ions clean and etch integrated circuits. Electronics, June 7 (1973), p. . Gas plasmas dissolve resists on integrated-circuit wafers--and etch circuit patterns--in a process developed by Mitsubishi Electric Corp. Among the approach's advantages are high yield, fine fine widths, and a cut in processing steps and time. What's more, the plasmas react to form harmless gases and water, which are easy to dispose of--unlike used acids and solvents.
Generating pulses with C - M O S flip-flops. F. J. MARLOWE and J. P. HASILI. Electronics, June (1973), p. . The C-MOS flip flop uses little power and can operate from a wide range
6. MICROELECTRONICS--COMPONENTS, SYSTEMS AND EQUIPMENTS 1024-Bit, N-Channel, M O S high-speed read/write memory. MOGI, MIYASAKAand ENOMOTO. Proceedings 4th Conference on Solid State Devices, Tokyo, 30 31 August (1972). Japan Soc. Appl. Phys. 42 (1973), p. 173. By employing conventional A1-Gate N-Channel MOS technology and modified bootstrap circuits, a 1024-bit dynamic Read/Write memory with faster access time (typical 65 ns.) in spite of lower clock voltages (+ 10.4 V with respect to V,.~;0 V) than any other MOS dynamic Read/Write memory devices described in publications to date has been designed and completed. This device can be packaged in either a 22-pin ceramic DIP or a 24-pin-QIP. Two devices of this 1024 bit memory in 24-pin-QIP packages can form a single, fully decoded, 2048-bit high speed memory module putting one on top of the other.
Digital panel meter. Design, operation and construction of an instrument with a solid-state display and based on an MOS, LSI chip. P. BARTLAM. Wireless World, April (1973), p. 163. Digital panel meters provide high accuracy and reliability of measurement compared with conventional analogue instruments. This meter is based on the technologies of large scale integration and solid-state light-emitting diode displays which provide the benefits of digital operation and miniature instrument size. Resulting from co-operation between Wireless World and Integrated Photomatrix Ltd, who designed the d.p.m., the meter is available as a complete kit of components. The kit costs £36.75 with an extra power supply or d.c.-d.c, converter if required (see p. 165). Instructions for the construction of the kit are given in the last section of this article.
Semiconductor memory C O F M O S 418. P. COUVELARD. Onde Elect. 53, Fuse. 5, May (1973), pp. 181 - 188. (In French). This article describes the principle and the organization of a 4 K 18 bits basic memory module named C O F M O S 418 and made with dynamic 1 K 1 bit MOS chips. We shall relate in detail all the peripheral circuits required by the matrix of 72 MOS memory chips, and we shall give one example of increasing memory capacity up to 32 K 18 bits, realized with the basic module described above, the input/ output logic had been provided to associate eight systems of this kind. This research has been executed thanks to a contract with the "D616gation/~ l'Informatique".
Biphase data transmission system uses IC one-shot as converter doubler. Electron. Design 8, April (1973). Biphase modulation is used in systems where clock information has to be contained within the data to minimize the number of transmission lines. Both the transmitter and the receiver of such a system can be implemented with an IC bidirectional one-shot. The 8T20 IC unit contains an input comparator that may be set to trigger an internal one-shot on the positive and negative edges of the incoming signal. Fast buffer store has self-control. J. STOCKTON. Electron. Engng, June (1973), p. 55. A t.t.l, buffer store, in which each section controls itself in accordance with its own state and
WORLD
ABSTRACTS
ON
MICROELECTRONICS
AND
RELIABILITY
and digital signals continue to increase, they become increasingly difficult to measure. One solution is to build a frequency counter that uses high-speed, emitter-coupled logic (ECL) in the front end and TTL ICs in the counter and timebase chain. If constructed properly, such a counter can measure frequencies in excess of 500 MHz.
of power-supply voltages (3-15 V). In addition, because of its high MOS input impedance, the flip-flop allows very large resistance and capacitance values to be used. For instance, a gated oscillator circuit containing 1-Mf~ resistors and 500-picofarad capacitors will have an input period of 20 min.
Touchless wafer handling. DONALD P. BAUMANN. Solid St. Technol., March (1973), p. 45. Semiconductor wafer processing is discussed with emphasis on wafer handling methods, it is suggested that the increasing high damage rate (and its critical cost) due to "manhandling" of wafers can be reversed by moving them on a linear dynamic air bearing. This appears to be the next step after flip-transferrable carriers. The t :chnique has been applied successfully to at least half a dozen common processing operators by both large and small manufacturers. The system is discussed in detail including comparisons and compatibility with other handling methods, costs, conversion from hand processing, and impact on the industry.
Maskentedmik fdr Integrierte Schaltkreise. DIETER WOLF. Rad. Mentor Electronic 39, No. 6, June (1973), p. 240. (In German). Cover feature, technology of the masks for integrated circuits. The lay-out for an IC is normally done in an enlarged scale of 10: l, 100: l, or 400: 1. This work is now computer-aided design. The masks can be drawn or cut, both methods have their advantages and their drawbacks. The different techniques are explained and possibilities for more rationalization are discussed. The six parts of the cover are the masks for the buried layer, the base diffusion, and the contact windows on the left from top to b o t t o m - - t h e separation, the emitter diffusion, and the aluminium conductors on the right from top to bottom.
Gold-flee film cuts LSI package cost. STEPHEN E. GROSSMAN. Electronics. May 10 (1973), p. 121. Palladium silver metalization, familiar to hybrid-circuit designers, now offers cost savings of 20 50 per cent to monolithic-device makers.
Plasma ions clean and etch integrated circuits. Electronics, June 7 (1973), p. . Gas plasmas dissolve resists on integrated-circuit wafers--and etch circuit patterns--in a process developed by Mitsubishi Electric Corp. Among the approach's advantages are high yield, fine fine widths, and a cut in processing steps and time. What's more, the plasmas react to form harmless gases and water, which are easy to dispose of--unlike used acids and solvents.
Generating pulses with C - M O S flip-flops. F. J. MARLOWE and J. P. HASILI. Electronics, June (1973), p. . The C-MOS flip flop uses little power and can operate from a wide range
6. MICROELECTRONICS--COMPONENTS, SYSTEMS AND EQUIPMENTS 1024-Bit, N-Channel, M O S high-speed read/write memory. MOGI, MIYASAKAand ENOMOTO. Proceedings 4th Conference on Solid State Devices, Tokyo, 30 31 August (1972). Japan Soc. Appl. Phys. 42 (1973), p. 173. By employing conventional A1-Gate N-Channel MOS technology and modified bootstrap circuits, a 1024-bit dynamic Read/Write memory with faster access time (typical 65 ns.) in spite of lower clock voltages (+ 10.4 V with respect to V,.~;0 V) than any other MOS dynamic Read/Write memory devices described in publications to date has been designed and completed. This device can be packaged in either a 22-pin ceramic DIP or a 24-pin-QIP. Two devices of this 1024 bit memory in 24-pin-QIP packages can form a single, fully decoded, 2048-bit high speed memory module putting one on top of the other.
Digital panel meter. Design, operation and construction of an instrument with a solid-state display and based on an MOS, LSI chip. P. BARTLAM. Wireless World, April (1973), p. 163. Digital panel meters provide high accuracy and reliability of measurement compared with conventional analogue instruments. This meter is based on the technologies of large scale integration and solid-state light-emitting diode displays which provide the benefits of digital operation and miniature instrument size. Resulting from co-operation between Wireless World and Integrated Photomatrix Ltd, who designed the d.p.m., the meter is available as a complete kit of components. The kit costs £36.75 with an extra power supply or d.c.-d.c, converter if required (see p. 165). Instructions for the construction of the kit are given in the last section of this article.
Semiconductor memory C O F M O S 418. P. COUVELARD. Onde Elect. 53, Fuse. 5, May (1973), pp. 181 - 188. (In French). This article describes the principle and the organization of a 4 K 18 bits basic memory module named C O F M O S 418 and made with dynamic 1 K 1 bit MOS chips. We shall relate in detail all the peripheral circuits required by the matrix of 72 MOS memory chips, and we shall give one example of increasing memory capacity up to 32 K 18 bits, realized with the basic module described above, the input/ output logic had been provided to associate eight systems of this kind. This research has been executed thanks to a contract with the "D616gation/~ l'Informatique".
Biphase data transmission system uses IC one-shot as converter doubler. Electron. Design 8, April (1973). Biphase modulation is used in systems where clock information has to be contained within the data to minimize the number of transmission lines. Both the transmitter and the receiver of such a system can be implemented with an IC bidirectional one-shot. The 8T20 IC unit contains an input comparator that may be set to trigger an internal one-shot on the positive and negative edges of the incoming signal. Fast buffer store has self-control. J. STOCKTON. Electron. Engng, June (1973), p. 55. A t.t.l, buffer store, in which each section controls itself in accordance with its own state and