Semiconductor Components Industries, LLC

Sanyo Semiconductor Co., Ltd.

Sanyo Electric Co., Ltd.

Yasuyuki Sayama

Hiroyasu Ishida

Tetsuya Okada

Zia Hossain

Tetsuro Asano

Makoto Oikawa

Kazunari Kushiyama

Takumi Hosoya

Syoji Miyahara

Toshikazu Matsui

Hiroki Eto

A semiconductor device structure includes a region of semiconductor material comprising a first conductivity type, an active region, and a termination region. A first active trench structure is disposed in the active region, and a second active trench structure is disposed in the active region and laterally separated from the first active trench by an active mesa region having a first width. A first termination trench structure is disposed in the termination region and separated from the second active trench by a transition mesa region having a second width and a higher carrier charge than that of the active mesa region. In one example, the second width is greater than the first width to provide the higher carrier charge. In another example, the dopant concentration in the transition mesa region is higher than that in the active mesa region to provide the higher carrier charge. The semiconductor device structure exhibits improved device ruggedness including, for example, improve unclamped inductive switching (UIS) performance.

Insulated gate semiconductor device having trench termination structure and method

Provided is a semiconductor wafer. In the semiconductor wafer, formation and etching of an n type epitaxial layer and formation and etching of a p type epitaxial layer are alternately performed for at least three times, so that all semiconductor layers are formed of epitaxial layers on a semiconductor substrate. Thereby, the respective semiconductor layers can be formed to have reduced widths. Thus, if a required breakdown voltage is the same, dopant concentrations of the respective semiconductor layers can be increased and a resistance value of the wafer can be reduced. In addition, a space portion remaining in the end is buried with an insulating layer, so that a defect can be avoided in a junction surface of the epitaxial layers.

Semiconductor device and method of processing the same

An n type impurity region is provided below a gate electrode. By setting a gate length to be less than a depth of a channel region, a side surface of the channel region and a side surface of the n type impurity region adjacent to the channel region form a substantially perpendicular junction surface. Thus, since a depletion layer widens uniformly in a depth direction of a substrate, it is possible to secure a predetermined breakdown voltage. Furthermore, since an interval between the channel regions, above which the gate electrode is disposed, is uniform from its surface to its bottom, it is possible to increase an impurity concentration of the n type impurity region, resulting in an achievement of a low on-resistance.

Method of manufacturing semiconductor device

The invention provides a method of manufacturing a semiconductor device at low cost in which the gate insulation film having a trench structure is not damaged by arsenic ions when the emitter layer or the like is formed and the insulation breakdown voltage is enhanced. A gate electrode made of polysilicon formed in a trench is thermally oxidized in a high temperature furnace or the like to form a thick polysilicon thermal oxide film on the gate electrode. Impurity ions are then ion-implanted to form an N type semiconductor layer that is to be an emitter layer or the like. At this time, the polysilicon thermal oxide film is formed thicker than the projected range Rp of impurity ions in the silicon oxide film for forming the N type semiconductor layer as the emitter layer or the like by ion implantation. This prevents a gate insulation film between the gate electrode and the N type semiconductor layer from being damaged by the impurity ions.

Formation and etching of an n type epitaxial layer and formation and etching of a p type epitaxial layer are alternately performed on the semiconductor substrate for at least three times to form all semiconductor layers, of the epitaxial layers. Thereby, impurity concentration profiles of the semiconductor layers can be uniform, and pn junctions can be formed vertically to a wafer surface. Furthermore, the semiconductor layers can each be formed with a narrow width, so that impurity concentrations thereof are increased. With this configuration, high breakdown voltage and low resistance can be achieved.

Method of processing semiconductor wafer

Provided is a semiconductor device in which an insulating region surrounding an element region is provided in an end portion of a semiconductor region with a super junction structure. Since a depletion layer in the element region ends in the insulating region, the end portion of the element region is not formed in a curved surface shape. In other words, the depletion layer has no curved surface in which internal electric fields are concentrated. For this reason, there is no need to take a measure to cause the depletion layer to spread in a horizontal direction by proving a terminal region. Since the terminal region is unnecessary, a chip size can be reduced. Alternatively, an area of the element region can be expanded.

Growing community of inventors

Gunma, Japan

Yasuyuki Sayama