Electrical Characteristics of Germanium $\hbox{n}^{+}/ \hbox{p}$ Junctions Obtained Using Rapid Thermal Annealing of Coimplanted P and Sb

Abstract

Highly activated n-type dopant is essential for n+ /p germanium diodes which will be in use for source/drain regions in Ge n-MOSFETs as geometry scaling proceeds. Rapid thermal annealing of coimplanted P and Sb in Ge has provided n-type dopant activation beyond 1 × 1020 cm-3. However, there are limited reports on the electrical characteristics of these junctions. This letter has investigated the temperature-dependent diode I-V characteristics and contact resistance of metal-n+ Ge contacts. Well-behaved n+ /p Ge diodes (Ion/Ioff >; 105 and η <; 1.2) and significantly reduced contact resistance (ρc ~ 8 × 10-7 Ω · cm2) have been demonstrated.