WORLD baking, etching and techniques.
Metallization
ABSTRACTS
ON MICROELECTRONICS
washing, photoresist removal
systems
for integrated
circuits.
R. W. WILSON and L. E. TERRY. Proc. Teeh. Prog. I N T E R / N E P O N 1970, Brighton, 13-15 October (1970), p. VIII-1. A metallization system must satisfy certain conditions if it is to be used in the fabrication of semiconductor devices. These conditions or constraints are as follows : A. The material should have a high conductivity (0 < 1 0 ~ n/era). B. It should have good adhesion to both the semiconductor material and to thermally grown or deposited dielectric films. C. The metal or metals should be free from degrading
ington D.C., U.S.A., 10-12 May (1971), p. 408. The Meteorological Data Sounding System measures the meteorological characteristics of the atmosphere. The $254 is the transmitter that was designed for this system to transmit the temperature and relative humidity data to the ground station from a balloon-borne payload during the ascent and descent. The transmitter consists of three major sections : the modulator/voltage regulator, the oscillator and antenna. The described transmitter delivers a minimum of 50 m W over the --70 ° to +70°C temperature range while the input voltage is varied between 30 and 20V. The transfer characteristic (resistance as a function of frequency) of the modulator is accurate enough to permit the determination of atmospheric temperature to within one-half a degree.
Microprogramming m a d e e a s y - - w i t h a 4,096-bit bipolar ROM. S. SIRKIN. Electronics, 15 March (1971), p. 64. Complex digital systems need complex, expensive control systems; but the latest bipolar processing techniques have produced a fast ROM that's large enough for the job and can save about $100 per device used.
The effects of in-process heating on K1200 monolithic multilayer capacitors. R. F. TINDALL. Proc. Tech. Prog. I N T E R / N E P C O N 1970, Brighton, 13-15 October (1970), p. VI-46. It is well known that while ceramic capacitors are among the most reliable components available, the high K types do exhibit considerable capacitance variations with temperature and time. The result of these variations is that it is difficult for the user to predict the capacitance value of a K1200 capacitor after a temperature change has occurred, either during processing of the circuit or during the life of the capacitor, to any precision better than, say ~ 1 0 per cent. This paper describes a series of exploratory experiments in which an attempt has been made to evaluate the changes in capacitance experienced by K1200 chip capacitors as a result of heating, and the
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intermetallie compounds not only between metal films, but between the metal and the semiconductor. D. Should make a good low ohmic contact to both p and n type siiicon. E. Amenable to practical production methods of deposition and delineation. F. Resistant to current-induced electro-migration. G. Resistant to electro-chemical corrosion. H. The deposition of the metal or metals must not introduce surface instabilities in the semiconductor material. I.
6. M I C R O E L E C T R O N I C S - - C O M P O N E N T S , A hybrid thin-film radiosonde transmitter. R. E. ASKEW. Proc. 21st Electronic Components Conf., Wash-
AND RELIABILITY
The metallization system must be compatible with LSI arrays involving multilayer interconnection processing.
SYSTEMS AND EQUIPMENTS
subsequent recovery from heating. It is hoped that these results will enable the user to predict with a fair degree of certainty, the behaviour of these capacitors.
Capacitors in m i c r o w a v e integrated circuits. H. KATOH. Trans. Inst. Elec. Comm. Engrs Japan 54-B, No. 3, March (1971), p. 95. (In Japanese.) An expression for the complex impedance of thin film capacitors whose electrodes come in from opposite sides has been derived, including the distributed resistive and inductive effect of the electrode. The result indicates that at microwave frequencies the resistance and reactance of capacitors are due mainly to that of the electrodes. Furthermore, the loss factor of such capacitors as Tantalum thin film capacitors, SiO thin film capacitors and ceramic chip capacitors was confirmed experimentally by measuring the change in Q of a strip-line resonant system with the addition of them.
The use of passive chip components in hybrid integrated circuits. D. W. HAMER. Pro& 21st Electronic Components Conf., Washington D.C., U.S.A., 10-12 May (1971), p. 27. This paper looks at the various reasons a hybrid integrated circuit manufacturer would have for using passive chip components in his designs, rather than using thick or thin integrated circuit technology for fabrication of these elements. Emphasis in this analysis is placed on resistors and capacitors (rather than all types of discrete components) and on chips (rather than on minicomponents and other leaded devices).
MOSFETS rejuvenate old design for CATV broadband amplifiers. D. V. LEE. Electronics, 15 March (1971), p. 72. The large dynamic range and low crossmodulation distortion of low-cost ~[OSFETs, plus a distributed-amplifier configuration, can provide a highlevel output suitable for v.h.f, coverage.
The m e a s u r e m e n t of linear circuits with a computer-operated system. G. MILLER. Proc. Tech.