It has been predicted that Ge transistors should exhibit faster switching speed than Si devices of comparable geometry, due to the higher electron and hole mobility in germanium. The development of techniques for the deposition of masking films and diffusion of donors and acceptors in Ge enables processing of double diffused planar transistors in a manner similar to those used in silicon. This paper describes and discusses these processes for both

and

transistors. The dc and high-frequency performance of these transistors reach expected values and indicate a superiority of germanium in high-speed performance.