GaN负电子亲和势光电阴极的激活改进研究

INVESTIGATION IMPROVEMENT ACTIVATION OF GaN NEGATIVE ELECTRON AFFINITY PHOTO-CATHODES

摘要: 采用低压金属有机化学气相沉积法在蓝宝石(0001)衬底上生长2～5μm厚度的P-AlxGa1-xN/GaN层(0<_X≤0.4),在Al_xGa1-_xN层中的Al浓度为0.2<X<0.7。P型GaN激活层的电子扩散长度确定为2～5μm,并获得3×10¹⁹ cm^-3的掺杂浓度。提出的GaN基光电阴极的表面能带结构模型,对实验结果给予了比较满意的解释。

Abstract: Two to five micrometer thick P-AlxGa1-xN/GaN layers with 0＜X≤0.4 were grown by low-pressure metal organic chemical Vapour deposition on sapphire（0001）substrates.For Al concentrations 0.2＜X＜0.7 in the AlxGa1-xN layers,The assessment of P-type GaN active layers Shows electron diffusion Lengths of 2 to 5 μm for a doping level of 3×10¹⁹cm^-3。strcure model of energy bands for surface GaN-based phtocathode was and the result of experiment was satisfied with the model.