Growth of AlGaN-based multiple quantum wells on SiC substrates

Al0.2Ga0.8N/Al0.45Ga0.55N multiple quantum wells (MQWs) were grown on SiC substrates by metal–organic chemical vapor deposition. We studied the influence of well width and barrier width on the structural and optical properties of AlGaN MQWs in details. The MQWs structures prepared in this work all exhibited good periodicity and abrupt interfaces. When the barrier width was fixed, the thinner well was benefit to increase the integrated photoluminescence (PL) intensity of the MQWs and obtain a shorter ultraviolet wavelength. And the thicker barrier was also contributed to improve the optical properties while the well width remained the same. Compared with the effect of the well width, the emission wavelength of MQWs was less dependent on the barrier width. A 318-nm room-temperature PL emission was achieved when the well width and barrier width were 2.5 and 11 nm, respectively.