| 摘要 |
PURPOSE:To optimize a capacitance change rate, selectively and reverse withstanding voltage by a method wherein a recessed section is formed to a high- resistivity GaAs layer, an impurity is introduced to the recessed section through an ion implantation method, the impurity is activated through annealing in a short time and a Schottky contact is shaped in the recessed section. CONSTITUTION:An N<-> type GaAs layer 2 having impurity concentration of 5X 10<14>cm<-3> and thickness of 0.6mum is grown on an N<+> type GaAs substrate 1 having 10<18>cm<-3> as impurity concentration by using a vapor phase epitaxial method. An Si3N4 film 3 is formed, an opening section having a desired area is shaped to the Si3N4 film 3, and the N<-> type GaAs layer 2 is etched while using the Si3N4 film 3 as a mask to form a recessed section 4 in the N<-> type GaAs 2. Si ions 5 are implanted while employing the Si3N4 film as a mask. Si ions are implanted, and an N type ion implantation layer 6 is shaped through annealing for 10sec. at 1,000 deg.C by using an infrared ray lamp. Al is vacuum-deposited to shape a Schottky contact 7 in the recessed section 4, and an ohmic electrode 8 is formed on the N<+> GaAs substrate. |
