| 摘要 |
PURPOSE: To suppress the generation of large leak current in a semiconductor device having an enhancement type MOS structure. CONSTITUTION: In an enhacement type transistor, a heavily doped P area 17 formed in the channel area under a gate electrode 13 is formed in such a manner that it will be in contact with a source area 15b but not a drain area l5a. Thus, the PN joint between the drain area 15a and the area 17 is eliminated, reducing the leak current. In addition, the distance between the area 15a and area 17 is set in such a way that even if a depletion layer expanding during application of operation voltage in the area 15a is expanded in the inside of the area 17, the electric field within the depletion layer may not reach the critical electric field where avalanche breakdown or Zener breakdown is generated. Therefore the increase of leakage current due to avalanche breakdown or Zener breakdown can be suppressed. |
