| 摘要 |
PURPOSE:To inhibit the threshold voltage from being varied and to lower the value of resistance by forming impurity regions with self-alignment method and regulating the distances between the gate electrode and the impurity regions by means of side etching. CONSTITUTION:An N type GaAs active layer 2, a W5Si film 3 and an AlN film 4 are formed on a GaAs substrate 1 successively in that order. After the W5Si3 film 3 is patterned to form a gate electrode, Si ions are implanted to form N<+> type source region 5 and N<+> type drain region 6. The W5Si3 film 3 is etched in its sides to regulate the distances from the gate electrode 3 to the N<+> type source and drain regions 5 and 6. An SiO2 film 7 and a resist film 8 are formed. After only the AlN film 4 is removed, an Ti/Au film 9 is formed to cover the whole surface and then removed except for the portion of the film 9 present on the gate electrode 3. After the SiO2 film 7 is removed, an Au.Ge/Au film is formed and patterned to form a source electrode 10 and a drain electrode 11. |
