| 摘要 |
PURPOSE:To alleviate accuracy by the alignment of photolithography, and to facilitate high-frequency operation by forming a source region in deep depth and a drain region in a shallow depth. CONSTITUTION:A plasma silicon oxide film 2 is deposited onto a semi-insulating GaAs substrate 1. The oxide film 2 is etched through CF4 RIE, leaving the plasma silicon oxide film 2 only in a channel region and a drain region in a field-effect transistor (FET) through photoetching. A plasma silicon nitride film 3 is deposited on the whole surface, and etched through CF4 RIE, leaving the plasma silicon nitride film 3 only in the channel region. Sections except the FET are coated with a resist 4 through a photolithographic technique, and ions are implanted to the whole surface. The plasma silicon oxide film 2 and the nitride film 3 are removed, and an implanting layer 5 is activated through annealing at 820 deg.C in an arsine atmosphere. A plasma silicon nitride film 9 is deposited, and a source electrode 6, a drain electrode 7 and a gate electrode 8 are formed. |
