SiAs (Silicon Arsenide)

A layered van der Waals group IV–V semiconductor, space group C2/m, built from puckered Si–As layers with strong in-plane structural anisotropy. It is a wide-bandgap semiconductor (~1.6–1.9 eV) exhibiting pronounced anisotropic optical, electrical, and vibrational (Raman) responses arising from its low-symmetry layered structure. These properties, together with a strong and polarization-sensitive photoresponse, make SiAs a candidate for anisotropic optoelectronics, polarization-sensitive photodetectors, and two-dimensional electronic devices.