利用X射线衍射研究Mg掺杂的InN的快速退火特性

Rapid Thermal Annealing Characteristics of Mg-Doped InN by X-Ray Diffraction

研究了不同的快速退火(RTA)温度对Mg掺杂的InN材料的影响。根据马赛克微晶模型,利用X射线衍射(XRD)技术,对样品的对称面和非对称面做ω扫描,并且通过倒异空间图(RSM)扫描,拟合得到了刃位错与螺位错密度,并且根据在不同快速退火温度条件下位错密度的比较,同时结合迁移率的测量结果,发现快速退火温度采用400℃能有效地提高晶体的质量。原因在于快速退火能有效地激活Mg原子活性,降低材料中的载流子浓度,同时快速退火采用的氮气气氛能补偿部分起施主作用的氮空位,降低材料中载流子浓度的同时也降低了缺陷。同时,(002)面的摇摆曲线半峰全宽(FWHM)也很好地验证了所得结果。

Dependence of Mg doped InN characteristics on the rapid thermal annealing （RTA） temperature is investigated. The mosaic tilt, twist and correlation lengths of InN film are determined by using X-ray diffraction （XRD） symmetrical and asymmetrical reflections as well as reciprocal spacing mapping （RSM）, which will then lead to the screw and edge dislocations. Comparing with the dislocations and mobility in different RTA temperatures, the crystal qualities are greatly improved at 400 ~C. We suggest that Mg atoms are activated by the RTA treatment, along with the reduction of carrier concentration. At the same time, N vacancies, which act as donors, are partly compensated when annealing in N2 atmosphere, leading to the reduction of defects and dislocations as well as carrier concentration. Such results also corroborate with the full width of half maximum （FWHM） of ω scans of InN （002） plane.