Delta-Doping of Si in GaN by Metalorganic Chemical Vapor Deposition

Si delta-doping in the GaN layer has been successfully demonstrated by metalorganic chemical vapor deposition. From the capacitance-voltage measurement, a sharp carrier concentration profile with a full width at half-maximum of 4.1 nm has been achieved with a peak concentration of 9.8×1018 cm-3. Si delta-doping concentration increases and then decreases with an increase in delta-doping time, and the use of a post-purge step in the ammonia ambient reduces Si delta-doping concentration. This indicates that delta-doping concentration is limited by the Si desorption process due to high growth temperatures.