Abstract: A semiconductor device is disclosed. In a surface layer of a front surface of an n-type semiconductor substrate, an anode layer is provided in an element activation portion and an annular p-type guard ring and an n-type high-concentration surface region are provided in an annular termination breakdown voltage region which surrounds the outer circumference of the anode layer. The impurity concentration of the n-type high-concentration surface region is higher than that of the semiconductor substrate and is lower than that of the p-type guard ring. The depth of the n-type high-concentration surface region is less than that of the guard ring. The anode layer and the guard ring are formed while the oxygen concentration of the semiconductor substrate is set to be equal to or more than 1×1016/cm3 and equal to or less than 1×1018/cm3.

Abstract: A method of manufacturing an RC-IGBT provided with an IGBT and an FWD on the same substrate is provided. First, top surface device structures of an IGBT and an FWD are formed on the top surface of a semiconductor substrate. Then, with the side of an IGBT region on the top surface of the semiconductor substrate shielded by a first shielding mask, only an FWD region is irradiated with light ions. Next, with the side of the FWD region on the bottom surface of the semiconductor substrate shielded by a second shielding mask, only the IGBT region is irradiated with light ions. With this, a first lifetime control region 10-1 is formed on the collector side A2 in the IGBT region A1-A2 and a second lifetime control region 10-2 is formed on the anode side B1 of the FWD region B1-B2.

Abstract: A method of manufacturing a semiconductor device is disclosed. The method includes forming a first trench and a second trench in an n-type substrate surface, the first trenches being spaced apart from each other, the second trench surrounding the first trenches, the second trench being wider than the first trench. The method also includes forming a gate oxide film on the inner surfaces of the first and second trenches, and depositing an electrically conductive material to the thickness a half or more as large as the first trench width. The method further includes removing the electrically conductive material using the gate oxide film as a stopper layer, forming an insulator film thicker than the gate oxide film, and polishing the insulator film by CMP for exposing the n-type substrate and the electrically conductive material in the first trench.

Abstract: A method of manufacturing a semiconductor device is disclosed. The method includes forming a first trench and a second trench in an n-type substrate surface, the first trenches being spaced apart from each other, the second trench surrounding the first trenches, the second trench being wider than the first trench. The method also includes forming a gate oxide film on the inner surfaces of the first and second trenches, and depositing an electrically conductive material to the thickness a half or more as large as the first trench width. The method further includes removing the electrically conductive material using the gate oxide film as a stopper layer, forming an insulator film thicker than the gate oxide film, and polishing the insulator film by CMP for exposing the n-type substrate and the electrically conductive material in the first trench.

Abstract: A TMBS diode is disclosed. In an active portion and a voltage withstanding structure portion of the diode, an end portion trench surrounds active portion trenches. An active end portion which is an outer circumferential side end portion of an anode electrode is in contact with conductive polysilicon inside the end portion trench. A guard trench is separated from the end portion trench and surrounds it. A field plate provided on an outer circumferential portion of the anode electrode is separated from the anode electrode, and contacts both part of a surface of an n-type drift layer in a mesa region between the end portion trench and the guard trench and the conductive polysilicon formed inside the guard trench. The semiconductor device is high in withstand voltage without injection of minority carriers, and electric field intensity of a trench formed in an end portion of an active portion is relaxed.