Trapping lifetime and carrier mobility measurements in CuInSe/sub 2/ using surface-acoustic-wave technique

A novel technique based on the measurement of the frequency spectrum of the acoustoelectric current is used to determine the trapping time associated with dominant traps in p-type CuInSe/sub 2/. At room temperature, two trap levels with trapping time constant of 2*10/sup -4/ and 6.7*10/sup -5/ s are detected. Under white incandescent light, two more traps with trapping time constants of 1.4*10/sup -3/ and 6*10/sup -4/ s are detected. The minority (electron) and majority (hole) carrier mobilities in this material are also measured using the acoustoelectric technique, and they are 6+or-3 and 3.1+or-0.15 cm/sup 2//V-s, respectively. The hole carrier concentration was estimated to be around 5*10/sup 15/ cm/sup -3/, and the surface of the sample was depleted.<>