Patent ID: 7821029

Claim:
An electrostatic protection element to be provided in a semiconductor substrate, comprising: a semiconductor substrate of a first conductivity type; a first impurity layer of a second conductivity type, which is a conductivity type opposite to the first conductivity type, provided in the semiconductor substrate; a second impurity layer of the first conductivity type provided in the first impurity layer functioning as a gate; a third impurity layer of the second conductivity type provided in the second impurity layer functioning as a cathode; a fourth impurity layer of the second conductivity type provided in the first impurity layer spaced apart from the second impurity layer at a distance; a fifth impurity layer of the first conductivity type provided in the fourth impurity layer functioning as an anode; and a sixth impurity layer of the second conductivity type provided in the fourth impurity layer, wherein an impurity concentration of the fourth impurity layer is higher than that of the first impurity layer, and a bottom of the fourth impurity layer is deeper than that of the second impurity layer.