Al_xGa_(1-x)As/GaAs调制掺杂结构的MBE优化工艺生长

Optimization MBE technology growth of Al_ x Ga_(1-x)As /GaAs modula tion doped structure

通过对MBE工艺中影响GaAs和AlGaAs材料质量的生长关键工艺实验研究,优化了MBE生长AlxGa1-xAs/GaAs调制掺杂结构工艺。用GEN-ⅡMBE设备生长AlxGa1-xAs/GaAs调制掺杂结构材料,得到了高质量的AlxGa1-xAs/GaAs调制掺杂结构材料。用范德堡法研究材料特性,得到材料参数的典型值:二维电子气浓度在室温时为5.6×1011cm-2,电子迁移率为6000cm2/V·s;在77K低温时浓度达3.5×1011cm-2,电子迁移率为1.43×105cm2/V·s。用C-V法测量其浓度分布表明,分布曲线较陡。典型的器件应用结果为:单管室温直流跨导达280mS/mm,在12GHz时均有8dB以上的增益。

The materials of high quality Al x Ga 1-x As /GaAs modulation doped structures have been grown by GEN-ⅡMBE system.Through experiment investigation of the key growth factors which affect the material quality of GaAs and Al x Ga 1-x As ,the MBE technology of growth Al x Ga 1-x As /GaAs modulation doped structure has been optimized.The properties of this material are charac-terisited by Van de Pown method and electrochemistry C-V profiling.The results are:N 300K =5.6×10 11 cm -2 ,μ 300K =6000cm 2 /V·s;N 77K =3.5×10 11 cm -2 ,μ 77K =1.43×10 5 cm 2 /V·s.The good properties of this material have been proved.High quality HEMT device with this material is also fabricated.