| 摘要 |
PURPOSE:To reduce a short channel effect by forming an MESFET into a base body in which an impurity doped semi-insulating GaAs layer on a semi-insulating GaAs substrate and an extremely thin un-doped high-purity GaAs layer in approximately channel thickness are grown continuously by using vanadium. CONSTITUTION:A GaAs layer 22 containing vanadium is grown on a semi-insulating GaAs substrate 21 in an epitaxial manner in several micron thickness, and an un-doped high-purity GaAs layer 23 is grown continuously in the epitaxial manner. Silicon ions are implanted selectively to the high-purity GaAs layer 23, and annealed, thus forming an active region 24. Source-drain electrodes 26, 27 being in ohmic-contact are shaped through a lift-off by a gate electrode 25 and a photo-resist consisting of AuGe and sintering. When the un-doped layer under the active region 24 is extremely thin, currents by a short channel effect are inhibited by the vanadium doped layer 22. Accordingly, even when gate length is shortened in the extent of submicron, the threshold voltage of a GaAs MESFET does not vary, and the GaAs MESFET having conductance of high transmission can be prepared. |
