MOVPE growth and n-type conductivity control of high-quality Si-doped Al_(0.5)Ga_(0.5)N using epitaxial AlN as an underlying layer

摘要

Conductivity control of 1-μm-thick Si-doped Al_(0.5)Ga_(0.5)N using an epitaxial AlN underlying layer was realized by introducing CH_3SiH_3 during low-pressure metalorganic vapor phase epitaxy. Cathodolumines-cence measurements indicated that luminescence from a deep-level transition was caused by silicon doping. X-ray diffraction measurements showed that fluctuations of the tilt component of the c-axis increased with an increasing the silicon dopant flow rate. The electron concentration increased linearly with increasing the CH_3SiH_3 flow rate from 3.5 x 10~(17) cm~(-3) to 9.3 x 10~(17) cm~(-3).