Tunnel Diodes Based on n+-Ge/p+-Si(001) Epitaxial Structures Grown by the Hot-Wire Chemical Vapor Deposition

Abstract

n⁺-Ge/p⁺-Si(001) epitaxial structures are grown by hot-wire chemical vapor deposition from GeH₄ at a low substrate temperature (~325°C). Prototype tunnel diodes allowing for monolithic integration into Si-based integrated circuits are formed based on these structures. Doping of the n⁺-Ge layers with a donor impurity (P) to a concentration of >1 × 10¹⁹ cm^–3 is performed via the thermal decomposition of GaP. Distinct regions of the negative differential resistance are observed in the current–voltage characteristics of tunnel diodes.