A Developmental Germanium P-N-P Junction Transistor

A developmental germaniump-n-p junction transistor that may be readily made in the laboratory by alloying indium into opposite faces of a wafer of single-crystal n-type germanium is described. It is shown that this laboratory technique gives experimental transistors with desirable characteristics. Distribution curves of measured characteristics are given for a typical run of 118 units made and tested under similar conditions. Power gains up to 46 db, "alpha" up to 0.997, and noise factor (1 kc) as low as 6 db were achieved.