Patent attributes
A semiconductor device capable of integrally controlling thresholds of gate electrodes of transistors present in a region of one-conductivity-type and transistors present in a region of an reverse-conductivity-type while suppressing noise propagation is provided. A digital circuit region 123 and an analog circuit region 121 are provided on a P—Si substrate 101. P-wells 103 and 193 and N-wells 105 and 195 are provided in the analog circuit region 121. P-wells 107 and 197 and N-wells 109 and 199 are provided in the digital circuit region 123. A mesh-like deep N-well 111 is provided to contact with lower surfaces of the P-well 103 and the N-well 105. A mesh-like deep N-well 113 is provided to contact with lower surfaces of the P-well 107 and the N-well 109.
