A new tunnel diode structure

Summary form only, given as follows. Solid structure germanium tunnel diodes have been fabricated in slice form by standard semiconductor techniques, These devices represent successful conclusion of a program to improve tunnel diode reliability, provide for adaption to integrated circuitry and lower costs while maintaining or improving the electrical characteristics of present microwave tunnel diodes. Series resistance of these diodes is inherently very low permitting a closely controlled resistance to be added in series to assure uniform operating stability. Construction consists of evaporating alloy material and masking by photolithographic techniques; post alloy passivation and junction support is deposited by evaporation; reliable expanded contacts complete the basic structure. Design criteria, fabrication parameters and procedures for electrical evaluation of devices on the slice for use in processing will be detailed. Diode parameter spread is characteristically small on any slice. However variation of fabrication permits realization of Ip/Cv ratios from 0.01 to 7 ma/pf and resistive cutoff frequencies to 50 GHz. Electrical and mechanical parameters as well as resistance to environmental extremes and techniques for extension of these procedures to form microwave circuit components on the slice will be described.