| 摘要 |
PURPOSE:To stabilize the high resistivity while sustaining the high purity by a method wherein a mixture of organic arsenic and arsine AsH3 is used as the V group source while the title high resistant semiconductor layer is formed without adding a dopant attaining to the compensation level. CONSTITUTION:The EL2 concentration (a) is specified to be a little higher than the residual impurity concentration, i.e. in the concrete, the EL2 concentration of 3.3X10<15>cm<-3> is 1.1 times of the residual impurity concentration of 3X10<15>cm<-3>. In order to meet this requirement, the mixture of organic arsenic and arsine AsH3 at the ratio of 0.35:1 is used as the V group source. Besides, the deposition temperature (b) is specified at 630 deg.C. Firstly, this high resistant Al0.28Ga0.72As layer 4000Angstrom is deposited, next, an electron running layer GaAs 4000Angstrom and an electron feeding layer AlGa As 400Angstrom are deposited. Later, HEMT in gate length of 1mum is formed of this crystal using the conventional photolithography.
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