Investigation of the Photocurrent in Hot-Wall-Epitaxy-Grown BaIn 2 S 4 Layers

摘要: The photocurrent (PC) of hot-wall-epitaxy-grown BaIn2S4 layers was studied at different temperatures and for photoresponse intensities. With increasing temperature, the position PC spectra tended to shift toward longer wavelength. These peaks corresponded band-to-band transitions caused by intrinsic from valence band states conduction states. Also, bandgap variations were well matched equation E g(T) = g(0) − 3.79 × 10−3 T 2/(T + 499), where estimated be 3.0597 eV, 3.2301 3.2606 eV corresponding Γ 4(z), 5(x), 5(y), respectively. By use selection rule results spectroscopy, crystal field spin–orbit splitting found 0.1703 0.0306 Thus, intensity gradually decreased with decreasing temperature. decrease presence trapping centers associated native defects in layers. trap level a shallow donor-level type 20.4 meV, 1.6 meV below band. Consequently, these levels, which are related layers, believed limit