Growth of Single Crystalline ZnGeN$_{2}$ from Zn/Ge Melts

We present the first evidence for the growth of ZnGeN$_{2}$ from a nitrogen saturated Zn/Ge melt. ZnGeN$_{2}$ is the II-IV-V$_{2}$ compound semiconductor analogue of GaN. Results from photoluminescence spectroscopy and X-ray diffraction suggest that it is nearly identical to GaN in band gap and lattice constants, making it potentially suitable as a GaN substrate or replacement. To date, reported methods of synthesis have been limited to vapor phase deposition on highly lattice-mismatched substrates. The present technique, which does not require the use of substrate, yields hexagonal prisms of ZnGeN$_{2}$, 40-50 $\mu$m in length along the [0001] direction, and 3-5 $\mu$m wide in cross-section, capped by a round, polycrystalline dome of stoichiometric ZnGeN$_{2}$. This morphology is highly suggestive of a VLS-like growth mechanism and is evidence that ZnGeN$_{2}$ may melt congruently at the pressures and temperatures employed.