Patent ID: 7911031

Claim:
A semiconductor structure comprising: a substrate being doped with a first type of ions; a first doped well with a second type of ions, and formed in the substrate; a second doped well with the second type of ions, the first type of ions and the second type of ions being complementary, and the second doped well formed in the substrate; and a first depletion region and a second depletion region respectively formed by the first doped well and the substrate and the second doped well and the substrate, the first depletion region and the second depletion region being formed connected to each other, wherein the semiconductor structure is characterized in that the first doped well and the second doped well are jointly adapted to perform a voltage-controlled resistivity; the resistivity of the resistor relates to a first depth of the first doped well, a second depth of the second doped well, and a distance between the first doped well and the second doped well; the distance between the first doped well and the second doped well is configured according to a first ion concentration of the first doped well, a second ion concentration of the second doped well, and a third ion concentration of the substrate; the resistivity is higher than that of a well resistor formed in a single doped well with the second type of ions; the first doped well and the second doped well are formed with a tapered shape and quasi-linked by partially overlapping; and connection between the first and second doped wells is interrupted when a differential voltage applied on the first doped well and the second doped well increases.