Electrical transport properties in Ge hyperdoped with Te

Abstract

In this work we have successfully hyperdoped germanium with tellurium with a concentration peak of 10(21) cm(-3). The resulting hyperdoped layers show good crystallinity and sub-bandgap absorption at room temperature which makes the material a good candidate for a new era of complementary metal-oxide-semiconductor-compatible short-wavelength-infrared photodetectors. We obtained absorption coefficients ci higher than 4.1 x 10(3) cm(-1) at least up to 3 mu m. In this study we report the temperature-dependency electrical properties of the hyperdoped layer measured in van der Pauw configuration. The electrical behaviour of this hyperdoped material can be explained with an electrical bilayer coupling/decoupling model and the values for the isolated hyperdoped layer are a resistivity of 4.25 x 10(-3) Omega.cm with an electron-mobility around -100 cm(2) V-1 s(-1).