Accession Number : AD0424955

Title :   HIGH-FREQUENCY, DIFFUSED-BASE, GERMANIUM TRANSISTORS WITH VACUUM-DEPOSITED LEADS,

Corporate Author : HARRY DIAMOND LABS WASHINGTON D C

Personal Author(s) : Anstead,R. J. ; Wetzel,G. B. ; Meyer,O. L. ; Jones,M. L.

Report Date : 15 NOV 1963

Pagination or Media Count : 37

Abstract : The feasibility of using vacuum-deposited, aluminum leads to the base and emitter electrodes of high-frequency, mesa-type, diffused-base, germanium, P-N-P transistors was investigated. The aluminum was evaporated onto transistors with electrodes of two sizes: 2 by 6 mil and 4 by 12 mil. The yield and the overall performance of transistors with vacuum-deposited leads were poorer than with comparable transistors having thermal-compression bonded leads. The low yield with deposited leads was due to short circuits between the leads and the transistor die. Such shorts could be the result of the material used as the insulating medium or the technique used to apply the material. Yields in the deposited-lead fabrication step alone ran as low as 10 %. The poorer electrical performance of the deposited-lead transistors stems from the inability to apply proper cleanup etch to the surface of those devices. The transistors were made using photoengraving techniques entirely. The design considerations and fabrication processes are described in some detail. (Author)

Descriptors :   (*TRANSISTORS, GERMANIUM), (*HIGH FREQUENCY, TRANSISTORS), (*ELECTRIC TERMINALS, MANUFACTURING), VACUUM APPARATUS, ALUMINUM, PHOTOENGRAVING, ELECTRIC CURRENT, GAIN, BONDING, VAPOR PLATING, THERMAL JOINING, GOLD, CAPACITANCE, ELECTRIC WIRE

Distribution Statement : APPROVED FOR PUBLIC RELEASE