Photoluminescence property of ZnSnP2 by solution growth and normal freezing methods

The photoluminescence (PL) spectra of the bulk ZnSnP2 crystals grown by the solution growth (SG) and normal freezing (NF) methods are studied. The donor-acceptor pair transition, which possibly originates from the transition from the levels of Sri at Zn sites (Sn-Zn) to the Zn vacancy (V-Zn) levels, is observed using the crystals grown by SG method. The ionization energies of the Sn-Zn and VZn levels are estimated to be approximately 110 and 40-50 meV, respectively. The PL spectra of the crystals,grown by SG method exhibits free-to-bound transition. These results are the first step toward realizing the novel function or optical devices as a solar cell using ZnSnP2.