New advances in the junction Transistor

Abstract

The alloy junction transistor is formed by recrystallization of germanium from a molten alloy. The original single crystal base provides the nucleation centers and leads to an abrupt p-n transition of the Schottky type. The geometry of such transistors differs from parallel plane, and surface recombination is the major source of minority-carrier loss. A potential analogue solution to carrier flow has been developed which gives close agreement with measured minority carrier phenomena. By this means it is possible to estimate transistor performance, if surface recombination is known, and to evaluate surface recombination in an finished transistor whose performance is known. The high-frequency limitations of the alloy junction transistor can be explained in terms of the equivalent circuit, which can be derived experimentally and evaluated theoretically. The limiting factors are discussed, and it is shown how the investigation has made possible the development of a transistor which can oscillate up to 40 Mc/s, and is satisfactory as an RF amplifier up to 1.5 Mc/s. As an example of the use of transistors a small personal broadcast receiver is described. This uses 9 transistors, has a sensitivity almost equal to that of a vacuum tubs receiver, and gives loudspeaker output for a consumption of 100 m W from a 9-volt battery.