Halogen n-type Doping of Chalcopyrite Semiconductors

We theoretically identify the chemical thermodynamic boundary conditions that will produce n-type CuInSe ₂ via halogen doping. Remarkably, we find that due to the low formation energies of the intrinsic defects, V _Cu and In _Cu in CuInSe ₂, the growth conditions that maximize the halogen donor incorporation do not yield n-type conductivity, whereas the conditions that maximize the concentration of the intrinsic donor In _Cu do yield n-type conductivity. Under the latter conditions, however, the contribution of the halogen donors to the net donor concentration stays significantly below that of In _Cu.