High crystalline quality and flat a‐plane aluminum gallium nitride (AlGaN) films are obtained on Si‐doped AlN templates with a moderate silane (SiH4) flow rate by metal‐organic chemical vapor deposition (MOCVD). The effects of the SiH4 flow rate on the surface morphology, crystalline quality, stress state, and optical property of a‐plane AlN templates and AlGaN films are comprehensively investigated. As the SiH4 flow rate increases from 0 to 7.0 nmol min−1, the full width at half maximum of X‐ray rocking curve values along [0001]/[1–100] directions for the AlGaN films are monotonically reduced to 1124/1143 arcsec. Meanwhile, the surface root mean square roughness value is decreased to 0.88 nm. These achievements are attributed to the suppression of the anisotropy degrees and in‐plane stress of AlN templates. In addition, an excess SiH4 flow rate leads to deteriorated surface morphologies and increased basal plane stacking fault (BPSF) densities for both AlN and AlGaN films. This work suggests that doping AlN layers with an appropriate SiH4 flow rate is a promising route to obtain high‐quality a‐plane AlGaN films for efficient nonpolar deep ultraviolet (DUV) devices.

中文翻译：

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采用金属有机化学气相沉积法在掺杂 Si 的 AlN 模板上生长高质量非极性 a 面 AlGaN 薄膜

在具有适度硅烷（SiH4）金属有机化学气相沉积（MOCVD）的流速。SiH 的影响4综合研究了流量对a面AlN模板和AlGaN薄膜的表面形貌、晶体质量、应力状态和光学性能的影响。作为SiH4流速从 0 增加至 7.0 nmol min−1，AlGaN 薄膜沿 [0001]/[1-100] 方向的 X 射线摇摆曲线值的半峰全宽单调减小到 1124/1143 角秒。同时，表面均方根粗糙度值降低至0.88 nm。这些成就归功于 AlN 模板的各向异性程度和面内应力的抑制。此外，过量的SiH4流速会导致 AlN 和 AlGaN 薄膜的表面形貌恶化并增加基面堆垛层错 (BPSF) 密度。这项工作建议用适当的 SiH 掺杂 AlN 层4流速是获得用于高效非极性深紫外 (DUV) 器件的高质量 a 平面 AlGaN 薄膜的一条有前途的途径。