| 摘要 |
PURPOSE:To allow a first area and a second area to be formed using the same resist and a mark for alignment using the same resist too by using a positive- type resist of which exposure and development characteristics are not influenced by irradiation of ion beams and laminating the resist on a surface of a semiconductor substrate with its suitable thickness. CONSTITUTION:After a positive-type resist 2 for ultraviolet rays is coated and laminated on a semi-insulating GaAs substrate 1 to form an aperture 2, a hole is formed. Next, after an aperture 5 is formed in the resist 2, silicon ion is implanted into a channel area 6 using the resist 2 as a mark. Next, an aperture 7 is added and silicon ion is implanted into the channel area 6 and a channel area 8 using the resist 2 having the apertures 3, 5 and 7 as the masks. Then, after the removal of the resist and the cleaning of the GaAs substrate 1, the channel areas 6 and 8 are activated by annealing. Source, gate and drain electrodes are, therefore, formed to obtain a depletion FET10 and an enhancement FET20. Also, alignment of masks is carried out up to formation of the electrodes using the aperture 3 as the mask. |
