Delta-doped InGaP grown by low pressure metalorganic chemical vapor deposition

Abstract

Silicon-delta-doped In0.49Ga0.51P layers were grown at 560 °C, 640 °C, and 720 °C by low pressure metalorganic chemical vapor deposition. For the growth temperature 560 °C, the electron sheet concentration saturated at 5.9×1012 cm−2, which corresponds to a three-dimensional (3D) concentration of 1.5×1019 cm−3. The sheet concentration increases by factor 3.5 and even by factor 11 for growth temperatures 640 °C and 720 °C, respectively. The widths of doping profiles were less than 6 nm, indicating a strong carrier confinement in the V-shaped quantum well. Electron mobility in samples grown at 560 °C indicates the presence of acceptor impurities at a high density. In InGaP grown at 640 °C, compensation effects of background acceptors do not occur resulting in extremely sharp profiles with a full width at half-maximum of 1.9 nm and a peak concentration of 2.1×1019 cm−3. The highest electron sheet concentrations were obtained in samples grown at 720 °C.