SEMICONDUCTING PROPERTIES OF HEXAGONAL CHROMIUM, MOLYBDENUM, AND TUNGSTEN DISILICIDES

Self-consistent electronic property simulation of hexagonal CrSi2, MoS i2, and WSi2 is performed within the local density approximation using the semirelativistic linear muffin-tin orbital method. They are deduc ed to be narrow-gap semiconductors with indirect band gaps of 0.29, 0. 07, and 0.07 eV, respectively. The effective masses of holes and elect rons in the disilicides are of the same order. They are dose to the fr ee electron mass in CrSi2 and there is a certain reduction of the appr opriate values from chromium to tungsten disilicides. Carrier mobility calculations show that the scattering on acoustic phonons is dominant for the disilicides. The hole mobilities at 300 K are 42, 190, and 20 9 cm(2)/V s for CrSi2, MoSi2, and WSi2, respectively.