| 摘要 |
PURPOSE:To obtain a high breakdown strength semiconductor device, in which a logic circuit section is fined and the working speed of the logic circuit section is increased and higher voltage can be applied to a high breakdown strength section, by composing a diffusion layer as a drain in a MOS transistor for a circuit operated at low supply voltage of a low concentration region and a high concentration region. CONSTITUTION:A diffusion layer as a drain in a MOS transistor for a circuit operated at low supply voltage in a semiconductor device worked at two kinds or more of electrode voltage is composed of a low concentration region and a high concentration region. The MOS transistor in a high breakdown strength section and the MOS transistor in a logic circuit section (the low supply voltage side) are formed onto the same semiconductor substrate. A gate oxide film 105 is formed in the same film thickness both in the logic circuit section and the high breakdown strength section, and source-drain regions in the MOS transistor in the high breakdown strength section are constituted of high concentration regions 106 and a low concentration region 107 while source-drain regions in the MOS transistor in the logic circuit section are also organized of high concentration regions 108 and a low concentration region 109. |
