| 摘要 |
PURPOSE:To prevent generation of frame breaking layer of elements other than MESFET by deposition a gate metal after forming a protection film to the element which does not require gate metals such as resistor, capacitor, etc. CONSTITUTION:A channel layer 3 for MESFET and channel layer 3' for resistance are formed by ion implantation method to a semi-insulated GaAs substrate 1 with a photo resist 2 uses as the mask. A protection film 8 SiO2 is deposited to the entire part of wafer, it is then annealed for activation of dopant and SiO2 is not removed and is left to the area other than MESFET. Thereafter, a gate metal 4 is deposited and unwanted gate metal is removed by dry etching. The ion implantation is then carried out with the photo resist 2 and gate electrode 4 used as the mask as in the case of existing device. Thereby, a source drain region including a large amount of dopant can be formed and a source drain electrode 6 can also be formed. |
