The thermal effect of the growth temperature on interface morphology and stimulated emission in ultraviolet AlGaN/InGaN multiple quantum wells (MQWs) are experimentally investigated. During the MOCVD epitaxial growth of AlGaN/InGaN MQWs, the ramping rate from a lower temperature for InGaN quantum wells (QWs) to a higher one for AlGaN quantum barriers (QBs) is intentionally changed from 1.0°C/s to 4.0°C/s. Atomic force microscopy images show that the surface morphology of InGaN QWs, which is improved by a thermal effect when the growth temperature rises to the set value of the AlGaN QBs, varies with different temperature ramping rates. The results of stimulated emission indicate that the threshold pumping power density of MQWs is decreased with increasing temperature ramping rate from 1.0°C/s to 3.0°C/s and then slightly increased when the ramping rate is 4.0°C/s. This phenomenon is believed to result from the thermal degradation effect during the temperature ramp step. A long-time high-temperature annealing will reduce the density of indium-rich microstructures as well as the corresponding localized state density, which is assumed to contribute to the radiative recombination in the InGaN QWs. Given the great difference between optimal growth temperatures for AlGaN and InGaN layers, a higher ramping rate would be more appropriate for the growth of ultraviolet AlGaN/InGaN MQWs.

实验研究了生长温度对紫外AlGaN / InGaN多量子阱（MQW）中界面形态和受激发射的热效应。在AlGaN / InGaN MQW的MOCVD外延生长期间，故意将InGaN量子阱（QW）的较低温度到AlGaN量子势垒（QB）的较高温度的斜率从1.0°C / s更改为4.0°C / s。原子力显微镜图像显示，当生长温度升高到AlGaN QB的设定值时，通过热效应改善的InGaN QW的表面形态会随温度的上升速率而变化。受激发射的结果表明，MQW的阈值泵浦功率密度随温度上升速率从1.0°C / s增加到3而降低。0°C / s，然后在斜坡速率为4.0°C / s时略微增加。认为该现象是由于温度上升步骤期间的热降解效应引起的。长时间的高温退火将降低富铟微结构的密度以及相应的局域态密度，这被认为有助于InGaN QWs中的辐射复合。鉴于AlGaN和InGaN层的最佳生长温度之间存在巨大差异，较高的升温速率将更适合于紫外AlGaN / InGaN MQW的生长。长时间的高温退火将降低富铟微结构的密度以及相应的局域态密度，这被认为有助于InGaN QWs中的辐射复合。鉴于AlGaN和InGaN层的最佳生长温度之间的巨大差异，较高的升温速率将更适合于紫外AlGaN / InGaN MQW的生长。长时间的高温退火将降低富铟微结构的密度以及相应的局域态密度，这被认为有助于InGaN QWs中的辐射复合。鉴于AlGaN和InGaN层的最佳生长温度之间存在巨大差异，较高的升温速率将更适合于紫外AlGaN / InGaN MQW的生长。