General Semiconductor, Inc.

Megamos Corporation

Icemos Technology Corporation

Magepower Semiconductor Corp.

Third Dimension (3d) Semiconductor, Inc.

Magemos Corporation

Mageposer Semiconductor Corporation

Koon Chong So

Fwu-Iuan Hshieh

Yan Man Tsui

John Amato

True-Lon Lin

Danny Chi Nim

Samuel Anderson

Brian D Pratt

Richard A Blanchard

Max Sk Chen

William John Nelson

Fwu-Juan Hshieh

Yan Man Ysui

True-Lon Line

Shu-Hui Cheng

Fwu-Luan Hshieh

A semiconductor device includes unlined and sealed trenches and methods for forming the unlined and sealed trenches. More particularly, a superjunction semiconductor device includes unlined, and sealed trenches. The trench has sidewalls formed of the semiconductor material. The trench is sealed with a sealing material such that the trench is air-tight. First and second regions are separated by the trench. The first region may include a superjunction Schottky diode or MOSFET. In an alternative embodiment, a plurality of regions are separated by a plurality of unlined and sealed trenches.

Semiconductor devices with sealed, unlined trenches and methods of forming same

A method of manufacturing a semiconductor device includes providing semiconductor substrate having trenches and mesas. At least one mesa has first and second sidewalls. The method includes angularly implanting a dopant of a second conductivity into the first sidewall, and angularly implanting a dopant of a second conductivity into the second sidewall. The at least one mesa is converted to a pillar by diffusing the dopants into the at least one mesa. The pillar is then converted to a column by angularly implanting a dopant of the first conductivity into a first sidewall of the pillar, and by angularly implanting the dopant of the first conductivity type into a second sidewall of the pillar. The dopants are then diffused into the pillar to provide a P-N junction of the first and second doped regions located along the depth direction of the adjoining trench. Finally, the trenches are filled with an insulating material.

Method for manufacturing a superjunction device with wide mesas

A method of forming a trench MOSFET device includes depositing an epitaxial layer over a substrate, both having the first conductivity type, the epitaxial layer having a lower majority carrier concentration than the substrate, forming a body region of a second conductivity type within an upper portion of the epitaxial layer, etching a trench extending into the epitaxial layer from an upper surface of the epitaxial layer, the trench extending to a greater depth from the upper surface of the epitaxial layer than the body region, forming a doped region of the first conductivity type between a bottom portion of the trench and substrate, the doped region having a majority carrier concentration that is lower than that of the substrate and higher than that of the epitaxial layer, wherein the doped region is diffused and spans 100% of the distance from the trench bottom portion to the substrate, forming an insulating layer lining at least a portion of the trench, forming a conductive region within the trench adjacent the insulating layer and forming a source region of said first conductivity type within an upper portion of the body region and adjacent the trench.

Method of making a trench MOSFET device with improved on-resistance

A trench DMOS transistor device that comprises: (a) a substrate of a first conductivity type; (b) an epitaxial layer of first conductivity type over the substrate, wherein the epitaxial layer has a lower majority carrier concentration than the substrate; (c) a trench extending into the epitaxial layer from an upper surface of the epitaxial layer; (d) an insulating layer lining at least a portion of the trench; (e) a conductive region within the trench adjacent the insulating layer; (f) a body region of a second conductivity type provided within an upper portion of the epitaxial layer and adjacent the trench; (g) a source region of first conductivity type within an upper portion of the body region and adjacent the trench; and (h) one or more low resistivity deep regions extending into the device from an upper surface of the epitaxial layer. The low resistivity deep region acts to provide electrical contact with the substrate, which is a common drain region for the device. By constructing a trench DMOS transistor device in this fashion, source, drain and gate contacts can all be provided on a single surface of the device.

Trench DMOS device with improved drain contact

A trench MOSFET transistor device and a method of making the same. The device comprises: (a) a silicon substrate of first conductivity type; (b) a silicon epitaxial layer of first conductivity type over the substrate, the epitaxial layer having a lower majority carrier concentration than the substrate; (c) a trench extending into the epitaxial layer from an upper surface of the epitaxial layer; (d) an insulating layer lining at least a portion of the trench; (e) a conductive region within the trench adjacent the insulating layer; (f) a body region of second conductivity type provided within an upper portion of the epitaxial layer and adjacent the trench; (g) a source region of first conductivity type provided within an upper portion of the body region and adjacent the trench; (h) an upper region of second conductivity type within an upper portion of the body region and adjacent the source region, the upper region having a higher majority carrier concentration than the body region; and (i) a source contact region disposed on the epitaxial layer upper surface, wherein the source contact region comprises a doped polycrystalline silicon contact region in electrical contact with the source region as well as an adjacent metal contact region in electrical contact with the source region and with the upper region.

Trench MOSFET device with polycrystalline silicon source contact structure

A trench MOSFET device comprising: (a) a silicon substrate of a first conductivity type (preferably N-type conductivity); (b) a silicon epitaxial layer of the first conductivity type over the substrate, the epitaxial layer having a lower majority carrier concentration than the substrate; (c) a body region of a second conductivity type (preferably P-type conductivity) within an upper portion of the epitaxial layer; (d) a trench having trench sidewalls and a trench bottom, which extends into the epitaxial layer from an upper surface of the epitaxial layer and through the body region of the device; (f) an oxide region lining the trench, which comprises a lower segment covering at least the trench bottom and upper segments covering at least upper regions of the trench sidewalls; (g) a conductive region within the trench adjacent the oxide region; and (h) a source region of the first conductivity type within an upper portion of the body region and adjacent the trench. The lower segment of the oxide region is thicker than the upper segments of the oxide region in this embodiment.

Trench MOSFET having low gate charge

A method of forming a trench within a semiconductor substrate. The method comprises, for example, the following: (a) providing a semiconductor substrate; (b) providing a patterned first CVD-deposited masking material layer having a first aperture over the semiconductor substrate; (c) depositing a second CVD-deposited masking material layer over the first masking material layer; (d) etching the second masking material layer until a second aperture that is narrower than the first aperture is created in the second masking material within the first aperture; and (e) etching the semiconductor substrate through the second aperture such that a trench is formed in the semiconductor substrate. In preferred embodiments, the method of the present invention is used in the formation of trench MOSFET devices.

Method of forming narrow trenches in semiconductor substrates

A trench DMOS transistor having overvoltage protection includes a substrate of a first conductivity type and a body region of a second conductivity type formed over the substrate. At least one trench extends through the body region and the substrate. An insulating layer lines the trench and overlies the body region. A conductive electrode is deposited in the trench so that it overlies the insulating layer. A source region of the first conductivity type is formed in the body region adjacent to the trench. An undoped polysilicon layer overlies a portion of the insulating layer. A plurality of cathode regions of the first conductivity type are formed in the undoped polysilicon layer. At least one anode region is in contact with adjacent ones of the plurality of cathode regions.

Trench DMOS transistor having a zener diode for protection from electro-static discharge

A method for making trench DMOS is provided that utilizes polycide and refractory techniques to make trench DMOS which exhibit low gate resistance, low gate capacitance, reduced distributed RC gate propagation delay, and improved switching speeds for high frequency applications.

High speed trench DMOS

A trench DMOS transistor cell is provided that includes a substrate of a first conductivity type and a body region located on the substrate, which has a second conductivity type. At least one trench extends through the body region and the substrate. An insulating layer lines the trench and a conductive electrode is placed in the trench overlying the insulating layer. A source region of the first conductivity type is located in the body region adjacent to the trench. The trench has sidewalls that define a polygon in the plane of the substrate so that adjacent sidewalls contact one another at an angle greater than 90 degrees.

Growing community of inventors

Fremont, CA, United States of America

Koon Chong So