Charge transport in n-type As- and Sb-hyperdoped Ge

Abstract

This paper presents a systematic study of the charge transport behavior of heavily doped n-type Ge layers with As and Sb. A nonequilibrium method ion implantation followed by milliseconds flash lamp annealing is applied to synthesize the n++ Ge layers (Ge:As and Ge:Sb). The resulting materials contain free electrons with a density above 3 × 1019 cm−3 and mobility more than 220 cm2/(V s). Quantum corrections to the conductance in a magnetic field are observed at low temperatures. Weak localization persists up to 30 K in Ge:Sb, while only up to 10 K in Ge:As. Using the Hikami–Larkin–Nagaoka model to fit the magnetoconductance data, we obtain the phase coherence length lϕ of the hyperdoped Ge samples in the range of 70–163 nm. This study may pave a way to explore possible applications for quantum technologies utilizing As- and Sb-hyperdoped Ge.