Applying traditional semiconductor physics concepts to novel material can lead to technological breakthroughs on global scale. A recent example of this, recognized by a Nobel Prize in Physics in 2014, is how templated thin film growth, p-type doping, semiconductor alloying, and hetero-structures in GaN enabled blue- and white light emitting diodes (LEDs), and changed how people think about the lighting.

In this talk, I will focus on our recent research on semiconductor physics of novel nitride materials, including Cu3N, Sn3N4, CuTaN2, ZnSnN2 and others, for solar energy conversion applications. The growth of high-quality thin films with atomic nitrogen source, the control of type- and level of doping by tuning point defect physics will be discussed.

The two common scientific themes that emerge across these materials are “defect-tolerance”, the tendency of a semiconductor to keep its properties despite the presence of crystallographic defects; and “metastability”, including structural polymorphs, semiconductor alloys, atomic disorder, non-equilibrium defect, and thermochemically metastable materials.

This research was supported by U.S. Department of Energy.