Enhancement of initial layer‐by‐layer growth and reduction of threading dislocation density by optimized Ga pre‐irradiation in molecular‐beam epitaxy of 2H‐AlN on 6H‐SiC(0001)
Enhancement of initial layer‐by‐layer growth and reduction of threading dislocation density by optimized Ga pre‐irradiation in molecular‐beam epitaxy of 2H‐AlN on 6H‐SiC(0001)
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DOI：
10.1002/pssc.200983579
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发表时间：
2010-07
期刊：
影响因子：
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通讯作者：
H. Okumura;T. Kimoto;J. Suda
中科院分区：
文献类型：
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作者：
H. Okumura;T. Kimoto;J. Suda
采用射频等离子体辅助分子束外延技术，在6H-SiC(0001)衬底上采用3层台阶生长了300 nm厚的无成核层AlN薄膜。在氮化铝生长之前，提供了0到30秒的Ga束流。结果表明，Ga预辐照7s(∼1.6ML)有利于在生长初期实现AlN的逐层生长模式，降低AlN层中的穿线位错密度。螺旋型和刃型TDDS分别为∼10 6 cm-2和6×10 8 cm-2。(2010Wiley-VCH Verlag GmbH&Co.KGaA，Weinheim)
300-nm-thick AlN layers without a nucleation layer were grown on 6H-SiC (0001) vicinal substrates with 3-bilayer-height steps by rf-plasma-assisted molecular-beam epitaxy. A Ga beam was supplied for 0 to 30 seconds just before growth of AlN. The Ga pre-irradiation for 7 seconds (∼1.6 ML) was found to be effective for realization of the AlN layer-by-layer growth mode at an earlier stage of the growth and reduction of threading dislocation densities (TDD) in the AlN layers. The screw-type and edge-type TDDs were ∼106 cm-2 and 6×108 cm-2, respectively. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)