Patent ID: 8169047

Claim:
A semiconductor device comprising: (a) a semiconductor substrate of a first conductivity type; (b) a first well region formed in the semiconductor substrate, the first well region being of a second conductivity type opposite to the first conductivity type; (c) a first semiconductor region of the second conductivity type, the first semiconductor region being formed within the first well region; (d) a second semiconductor region of the first conductivity type, the second semiconductor region being formed so as to surround the first semiconductor region in a plan view; (e) a first conductor film formed so as to cover the first semiconductor region and the second semiconductor region and to be electrically coupled to the first semiconductor region and the second semiconductor region; (f) a first conductive portion electrically coupled to the first conductor film; (g) a separation portion formed over the semiconductor substrate, the separation portion being formed outside the second semiconductor region; (h) a third semiconductor region of the second conductivity type, the third semiconductor region being formed outside the second semiconductor region such that a portion of the separation portion is between the third semiconductor region and the second semiconductor region; (i) a second conductor film formed so as to cover the third semiconductor region and to be electrically coupled to the third semiconductor region; and (j) a second conductive portion electrically coupled to the second conductor film, wherein electrical coupling of the first semiconductor region and the first conductor film is of Schottky coupling, wherein the first semiconductor region and the second semiconductor region do not contact each other, wherein the second semiconductor region is formed at a peripheral portion of the first conductor film in the first well region, wherein an impurity concentration of the first semiconductor region is higher than an impurity concentration of the first well region, and wherein the first semiconductor region extends deeper into the first well region than does the separation portion.