A STUDY OF NEW SOURCE MATERIAL FOR GROWING InGaN SYSTEM IN LOW PRESSURE ORGANOMETALLIC CHEMICAL VAPOR PHASE DEPOSITION APPARATUS

在低压化学气相沉积装置的生长室中，首次用四极杆质量分析仪研究了一甲肼-三甲基镓和一甲肼-三甲基林钠体系的有效分解反应。结果表明，胺、甲胺、碳氢化合物等产物的生成温度低至30 0℃左右，随着温度的升高，与乙腈、二甲胺、单甲肼等中间产物一起形成稳定的氰化物和甲基氧化锌。采用monomethylhydrazine-trimethylgallium-trimethylindium低压化学气相沉积方法在GaN非晶层上连续生长InGaN薄膜，研究了中间产物在650℃以上的分解过程。结果表明，在650~750℃的生长温度范围内，由于衬底上三甲基镓分解生成的铟的解吸增加，InGaN层中的铟含量随着生长温度的升高而降低；在650℃恒定的三甲基镓中，生长层中的铟含量随着三甲基镓含量的增加而增加。

A quadrupole mass analyzer is for the first time used to study effective decomposition reactions of monomethylhydrazine-trimethylgallium and monomethylhydrazine-trimethylindium systems in a growth chamber of low-pressure chemical vapor deposition apparatus. It is found that the products such as amine, methylamine and hydrocarbons, are formed at a temperature as low as around 300℃ and that the stable cyane and monomethylcianide are formed together with intermediate products such as acetonitrile, dimethylamine, monomethylhydrazone, etc. as increasing the temperature. The intermediate products are decomposed above a temperature of approximately 650℃ in our apparatus.InGaN layers continuously grown on GaN amorphous layers by a low-pressure chemical vapor phase deposition method using monomethylhydrazine-trimethylgallium-trimethylindium were examined. It is found that the indium content in InGaN layers decreased with the increasing growth temperature from 650 to 750℃ due to the increasing desorption of indium formed on the substrates from the decomposition of trimethylinjium and that the indium content in grown layers increased with increasing the trimethylgallium under the constant trimethylindium at 650℃.