Abstract: A semiconductor device of the present invention comprises a semiconductor chip, metal layers formed on a first main surface of the semiconductor chip, a first conductive layer layered on a second main surface of the semiconductor chip, consisting of a plurality of conductive films, a second conductive layer layered on the metal layer, having a layered structure consisting of a plurality of conductive films formed in the same order as in the first conductive layer as viewed from the semiconductor chip and a third conductive layer layered on the metal layer, having a layered structure consisting of a plurality of conductive films formed in the same order as in the first conductive layer as viewed from the semiconductor chip. The plurality of conductive films comprise a nickel film and a low contact resistance conductive film having contact resistance with the semiconductor chip which is lower than that of the nickel film.

Abstract: A semiconductor device includes a silicon oxide film (2) formed in a predetermined region on a single crystalline silicon substrate (1) and a gate dielectric film (3) as a thermal oxide film formed by performing thermal oxidation on the surface of the substrate (1) in a region adjacent to the silicon oxide film (2). A polycrystalline silicon (5) (or amorphous silicon) having an oxidized surface is formed on the border between the silicon oxide film (2) and gate dielectric film (3).

Abstract: A first insulator (710) having an opening within a central region (551) is formed on a main surface (61S) of an epitaxial layer (610). Then, p-type impurities are ion implanted through the opening of the first insulator (710) and then heat treatment is carried out, thereby to form a p base layer (621) in the main surface (61S). An insulating film is formed to fill in the opening and then etched back, thereby to form a second insulator (720) on a side surface (71W) of the first insulator (710). Under conditions where the second insulator (720) is present, n-type impurities are ion implanted through the opening and then heat treatment is carried out, thereby to form an n+ source layer (630) in the main surface (61S) of the p base layer (621).

Abstract: A second trench (105b) is formed inside a semiconductor layer (102), penetrating a base layer (103) and moreover extends along a second direction (D2) while being connected to one end portion of each first portion (P1) of a first trench (105a) extending along a first direction (D1). A second gate control electrode (107b) is connected to a first gate control electrode (107a) at the one end portion, filling the inside of the second trench (105b). A gate contact portion (109) extending along the second direction (D2) exposes part of an upper surface of the second gate control electrode (107b). A gate aluminum electrode (108) is connected to the second gate control electrode (107b) through the gate contact portion (109), protruding outside beyond an end (103e) of the base layer (103) by a distance (W0).

Abstract: A second trench (105b) is formed inside a semiconductor layer (102), penetrating a base layer (103) and moreover extends along a second direction (D2) while being connected to one end portion of each first portion (P1) of a first trench (105a) extending along a first direction (D1). A second gate control electrode (107b) is connected to a first gate control electrode (107a) at the one end portion, filling the inside of the second trench (105b). A gate contact portion (109) extending along the second direction (D2) exposes part of an upper surface of the second gate control electrode (107b). A gate aluminum electrode (108) is connected to the second gate control electrode (107b) through the gate contact portion (109), protruding outside beyond an end (103e) of the base layer (103) by a distance (W0).

Abstract: An insulator film provided on a region for arranging a Zener diode has a plurality of groove portions successively arranged in a direction D1 of extension of each semiconductor region forming the diode. Each groove potion extends in a width direction D2 of each semiconductor region, and has a depth T3. Each semiconductor region is arranged on the upper surface of the insulator film. Therefore, it follows that each semiconductor region has a plurality of irregular shapes arranged in the direction D1 of extension and the Zener diode has a peripheral length not only in the transverse direction D1 but also in a vertical direction D3, so that a p-n junction area in the Zener diode is increased. Thus, parasitic resistance of an input protection Zener diode is reduced for improving a gate insulator film protective function of the diode.

Abstract: An insulator film provided on a region for arranging a Zener diode has a plurality of groove portions successively arranged in a direction D1 of extension of each semiconductor region forming the diode. Each groove potion extends in a width direction D2 of each semiconductor region, and has a depth T3. Each semiconductor region is arranged on the upper surface of the insulator film. Therefore, it follows that each semiconductor region has a plurality of irregular shapes arranged in the direction D1 of extension and the Zener diode has a peripheral length not only in the transverse direction D1 but also in a vertical direction D3, so that a p-n junction area in the Zener diode is increased. Thus, parasitic resistance of an input protection Zener diode is reduced for improving a gate insulator film protective function of the diode.

Abstract: The present invention relates to an insulated gate semiconductor device and a method of manufacturing the same, and more particularly to an improvement for enhancing a gate breakdown voltage. In order to achieve the object, gate wirings (9), (10) and (13) are provided to keep away from an upper end (UE) of an edge of a gate trench (6) along its longitudinal direction. More specifically, the gate wiring (9) coupled integrally with an upper surface of a gate electrode (7) is formed apart from the upper end (UE) and the gate wiring (10) is formed on an insulating film (4) also apart from the upper end (UE). The two gate wirings (9) and (10) are connected to each other through the gate wiring (13) formed on a BPSG layer (11). Moreover, an upper face of the gate electrode (7) is positioned on the same level as an upper main surface of a semiconductor substrate (90) or therebelow in the vicinity of the upper end (UE).

Abstract: In order to prevent an etch-down phenomenon in a gate electrode (106), a source electrode (108) is connected to an upper major surface of a semiconductor substrate (160) through openings (112, 112a) of a protective film (107), while a gate wire (109) is connected to the gate electrode (106) through an opening (111). The opening (112, 112a) are formed by dry etching, whereby the source electrode (108) is reliably insulated from the gate electrode (106). On the other hand, the opening (111) is formed by wet etching, whereby the gate electrode (106) is not etched down. Thus, it is possible to prevent short-circuiting defectiveness across the gate electrode (106) and the semiconductor substrate (160) resulting from an etch-down phenomenon of the gate electrode (106) while guaranteeing electrical insulation between the gate electrode (106) and the source electrode (108).