| 摘要 |
PURPOSE:To enable to control threshold voltage on a wide range of area by a method wherein, in an MOS type semiconductor device, a compound semiconductor is used at least for a gate electrode among the electrodes of which said semiconductor device is composed. CONSTITUTION:Three n<+> type diffusion regions 12 are formed on the surface part of a p type InP substrate 11, and an n<+> type InP gate 14 and a p<+> type InP gate 15 are coated on the surface located between the center and the region 12 on both sides through the intermediary of a gate insulating film 3. As a result, the difference of threshold voltage of two MOSFETs will be turned to 1.28V irrespective of the material of the substrate 11. Also, if GaAs is used as gate material, the difference of threshold voltage is turned to 1.4V, it is turned to 3.75V if InSb is used, and it is turned to 2.4V if AlP is used. Thus, the desired threshold voltage is obtained by selecting the compound semiconductor properly. |
