Semiconductor device

Abstract

Abstract PURPOSE:To detect with good response and accurately a rise in temperature at a junction part due to the flow of an electric current exceeding a rated current value and to prevent an element from being broken by a method wherein a layer constituting a temperature sensor such as a diode, a resistor or the like is formed on a semiconductor substrate via an insulating film. CONSTITUTION:An n<-> polycrystalline Si film 11 is grown on an oxide film 5 which is situated in an inactive region formed to enhance the breakdown strength, a polycrystalline Si film 6 and an oxide film 7 at a low temperature of about 800 deg.C; a p<+> layer 12 and an n<+> layer 13 are formed in the film; a p-n junction diode 10 is thus formed. A drop in a forward voltage at a low electric current value of this diode is temperature-dependent; accordingly, it the drop in the forward voltage is taken out from an electrode 14 brought into contact with the p<+> layer 12 and from an electrode 15 brought into contact with the n<+> layer 13, its temperature can be detected. Because the diode 10 is brought into contact with the surface of the semiconductor substrate via only the thin insulating films 5, 7 and the polycrystalline Si film 6, a thermal resistance value among these is low; a junction temperature between an n<-> layer 2 and a p<+> layer 32 of this power MOSFET can be detected with quick response; this detected value can be transmitted to a control circuit for a gate voltage.

Inventors

• 👤 Kenya Sakurai
• 👤 建弥 桜井

Bibliographic Details