Modification of strain relaxation process by Si doping in metamorphic Al(Ga)InAs layers grown on GaAs
Modification of strain relaxation process by Si doping in metamorphic Al(Ga)InAs layers grown on GaAs
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通过在 GaAs 上生长的变质 Al(Ga)InAs 层中掺杂 Si 来修改应变弛豫过程
DOI：
10.1166/mex.2016.1333
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发表时间：
2016-12
影响因子：
0.7
通讯作者：
Jianrong Dong
中科院分区：
文献类型：
--
作者：
Yang He;Yurun Sun;Yongming Zhao;Shuzhen Yu;Jianrong Dong
我们研究了Si掺杂对金属-有机化学气相沉积(MOCVD)法生长的Al(Ga)InAs缓冲层中位错运动的影响。结果表明，Si掺杂抑制了Al(Ga)InAs缓冲层中In的分凝和相分离的形成，从而降低了InP帽层的表面粗糙度和穿线位错密度。特别是Si取代III族原子作为n型掺杂，沿[110]方向进入B型台阶，Si掺杂对β位错的运动有明显的影响，从而促进β位错在界面滑移，降低β穿线位错密度。而Si杂质具有很强的锁定(111)滑移面上的α位错的能力，并最终改变[110]方向的倾斜度。由于掺杂对许多类型的光电子器件都是必不可少的，这些结果对于改善变质器件的材料性能和性能具有重要意义。
We investigated the effects of Si doping on the dislocation movements in the compositionally step-graded Al(Ga)InAs buffers grown by metal-organic chemical vapor deposition (MOCVD) on (001) GaAs substrates with 7° miscut toward (111)A. It is found that Si doping suppresses the In segregation and the formation of phase separation in the Al(Ga)InAs buffers to reduce the surface roughness and the threading dislocation density in InP cap layer. In particular, Si substitutes group III atoms as n-type doping for incorporating into B-type step along the [110] direction and the effect of Si incorporation on the movement of β dislocations is obvious, which consequently promotes β dislocations to glide in the interface and reduces the β threading dislocation densities. While Si impurity has a great ability to lock α dislocations on the (111) slip planes and eventually change the tilt in the [110] direction. Since doping is essential for many types of optoelectronic devices, these results are valuable for improving the material properties and performance of metamorphic devices.