ELECTROSTATIC DISCHARGE PROTECTION DEVICE

摘要

PURPOSE: An electrostatic discharge protection device is provided to increase a sustain voltage by including a first well and a second well with higher impurity doping density than the impurity doping density of the first well. CONSTITUTION: The impurity doping density of a first conductive first well(22A) is different from the impurity doping density of a first conductive second well(22B). A gate(23) is formed on the first well. A second conducive source area(25) is formed on the first well of one side of the gate. A second conductive drift area(26) crosses the first well and the second well in the other side of the gate. A second conductive drain area(27) is formed on the drift area and is overlapped with the second well.