Photoelectric properties of higher manganese silicide (HMS)-Si (Mn)-M structures

摘要

Photoelectric properties of (HMS)-Si(Mn)-M structures, where HMS is higher manganese silicide formed in diffusion doping of silicon with manganese and M is metal contact, have been studied in a wide range of temperatures and light wavelengths. After illumination of these structures with hν = 1.12 eV light at T = 77 K is terminated, the photocurrent decays back to the dark current in a complicated manner, following a curve with two regions. The duration of decay is about several seconds and more than l05 s in the first and second regions, respectively. Deep infrared (IR) and temperature quenching of photoconductivity in these structures have been studied. Under illumination with h ν≥1.12 eV light and at low temperatures these structures can be considered HMS--i--p--M structures, with the i-region playing essential role in the generation of space-charge-limited currents (SCLC). Breakdown of the SCLC mode in these structures by ionization of manganese levels with extra IR light (hν= 0.42 - 0.6 eV) or by heating results in a sharp decrease of the photocurrent flowing through the structures (especially in the case of temperature quenching in a narrow temperature range ΔT = 15-20 K).