Abstract: In a semiconductor device, risk of malfunction of a heat sensing diode on a main side of a vertical power semiconductor element is minimized by arranging the diode at the center of the element. Because the heat sensing diode is disposed at the center of the main side of the semiconductor element, the diode is protected from breakage and heat accumulation even when an excessive heat causes a crack at the periphery of a conductive bonding material that connects the element and the metal bodies on both sides of the element.