Electronic properties of (NH4)2S passivated InP(100) surfaces

We have recently presented a method that yields chemically and thermally stable S-passivated InP(100) – (1 × 1) surfaces. Here we characterize the surface electronic properties using two techniques: band edge and exciton photoluminescence intensity and Schottky diode current–voltage characteristic measurements. We compare etched and S-treated samples, both in the as-prepared condition and after annealing. These measurements show that the S-treated surfaces have better properties than the etched ones. In particular, photoluminescence intensities are improved by a factor of two to four.