| 摘要 |
PURPOSE:To enable to use any residual part as electrodes by a method wherein a semiconductor substrate selectively formed of impurity implanted regions is coated with metallic film and after implanting the metallic film with ion for modification, overall surface is etched to removed the part not yet modified. CONSTITUTION:When electrodes corresponding to a P-type region 1a and an N-type region 1b are formed on a GaAs substrate 1 formed of said regions, firstly a marker 2 as a reference to irradiating position of ion beams is formed on the surface of substrate 1 side to evaporate an Au film 3 on overall surface including the marker 2. Next the irradiating position with focussed ion beams is put together with region 1a making reference to the marker 2 and then the film 3 on the position is implanted firstly with Be ion and then Au ion to form a modified region 3a on the film 3, likewise another modified region 3b on the region 1b. Later the film 3 excluding the regions 3a, 3b is removed by etching process and annealed at the temperature exceeding 400 deg.C-500 deg.C to make the regions 3a, 3b fill the role of electrodes without using any mask. |
