Electrical transport properties in Ge hyperdoped with Te

Abstract

In this work we have successfully hyperdoped germanium with tellurium with a concentration

peak of 1021 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 α higher than 4.1×103 cm−1 at least up to

3 μm. 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 4.25×10−3Ω·cm with an

electron-mobility around −100 cm2 V−1 s−1.