不同深宽比GaAs衬底的Al_(2)O_(3)/HfO_(2)复合薄膜材料原子层沉积及能谱分析

ALD Deposition and Energy Dispersive Spectrum Analysis of Al_(2)O_(3)/HfO_(2) Composite Films on GaAs Substrates with Different Aspect Ratios

利用热原子层沉积(Atomic Layer Deposition,ALD)技术在不同深宽比GaAs衬底上进行了Al_(2)O_(3)/HfO_(2)复合薄膜的沉积。通过对其表面和能谱进行分析发现,沉积温度对复合薄膜的摩尔比具有较大的影响。随着深宽比的增大,其沉积表面和沟槽内会出现残留物;随着ALD沉积温度的上升,其沉积表面和沟槽内的残留物减少,摩尔比趋向均匀。当深宽比为2.2并利用150℃的低沉积温度时,表面及底面基本无残留物。但当深宽比为4.25时,150℃沉积明显有大量残留物。只有当温度升高到300℃时,表面和沟槽里复合薄膜的残留物才被明显消除。ALD技术可以实现各种器件结构的全方位钝化,这是其他化学气相沉积法无法比拟的。

Al_(2)O_(3)/HfO_(2)composite films were deposited on GaAs substrates with different aspect ratios by thermal atomic layer deposition(ALD).Through the analysis of surface and energy dispersive spectrum(EDS),it is found that the deposition temperature has a great influence on the molar ratio of the composite films.With the increase of the aspect ratio,there are residues on the surface and in the grooves.With the increase of the ALD deposition temperature,the residues on the surface and in the grooves decrease,the mole ratio tends to be uniform.When the aspect ratio is 2.2,using the low deposition temperature of 150℃,there are basically no residues on the surface and in the grooves.However,when the aspect ratio is 4.25,there is a large amount of residues.Only when the temperature rises to 300℃,the residues on the surface and in the grooves can be obviously eliminated.ALD technology can realize all-round passivation of various device structures,which is unmatched by other chemical vapor deposition(CVD).