Patent ID: 7067888

Claim:
A semiconductor device comprising , a plurality of field effect transistors provided on a common semiconductor substrate and operated at different voltages, which plurality of field effect transistors includes field effect transistors which are higher in operating voltage than others of said plurality of field effect transistors; wherein in the field effect transistors which are higher in operating voltage, of the plurality of field effect transistors, a first field effect transistor, which directly receives a signal inputted from outside, is configured so as to differ in drain structure from a second field effect transistor thereof which indirectly receives the signal inputted from outside, and wherein the drain structure of the first field effect transistor differs from the drain structure of the second field effect transistor in that the drain structure of second field effect transistor includes regions of opposite conductivity to one another while the drain structure of the first field effect transistor does not include regions of opposite conductivity from one another.