| 摘要 |
PURPOSE:To enable high-speed transistor action by a method wherein impurity ions are implanted in the gap region between the channel and the source-drain electrodes, but not in the channel part immediately under the gate electrode. CONSTITUTION:After a GaAs layer 22 is grown on a semi-insulation GaAs substrate 21, an AlGaAs layer 23 whose composition ratio of Al and Ga is about 0.3:0.7 is grown. The donor concentration in the GaAs layer 22 should be 10<16>cm<-3> or less. Next, a gate electrode 28 is attached on the epitaxial layer and thereafter Si ions 31 are implanted at 10<16>cm<-3> or more by using this metal electrode as a mask, and annealing is performed. Then, the source 25 and the drain electrode region 26 are formed, and further electrode metal Al's 29 and 30 are formed. Since the amount of impurity can be accurately controlled by ion implantation, the variability of characteristic can be reduced. |
