Fluoride Resonant Tunneling Diodes Co-integrated with Si-MOSFETs

Abstract

Resonant tunneling diodes (RTDs) composed of heteroepitaxial CaF2/CdF2/CaF2 structure grown on Si substrates were co-integrated with Si-metal oxide semiconductor field effect transistors (MOSFETs), and test circuits of the static random access memory (SRAM) cell were fabricated. The RTD structures were grown in the opened diode holes on the oxide film, where a high dose of phosphorus ions (P+) had been implanted. Surface roughening of ion-implanted Si before the fluoride growth due to an increase of the ion dose was investigated, and the optimum dose was determined. Normal operations of both fluoride RTD and Si-MOSFET in the fabricated circuit were obtained. Bistable operation was also observed for the circuit in which two RTDs were connected in series.