Alpha Omega Semiconductor Inc.

Micrel, Incorporated

Hideaki Tsuchiko

Sik Lui

Bruce Lee Inn

Phillip Fischer

Marty Garnett

The present invention is directed to a semiconductor chip comprising a high voltage device and a low voltage device disposed thereon. The chip may be formed in several different configurations. For example, the semiconductor chip may include a NPN bipolar transistor, PNP bipolar transistor, a diode, an N channel DMOS transistor and the like. the first doped well being configured as a base of the DMOS transistor, a P channel DMOS transistor and the like. These and other embodiments are described in further detail below.

Semiconductor chip integrating high and low voltage devices

A transistor includes a semiconductor body; a first gate electrode formed on a first portion of the semiconductor body and a second gate electrode formed on a second portion of the semiconductor body. A drain region is formed on a first side of the first gate electrode and a first source region is formed on a second side of the first gate electrode. The drain region is formed on a first side of the second gate electrode and a second source region is formed on a second side of the second gate electrode. A trench is formed in the semiconductor body and positioned in the drain region. A doped sidewall region is formed in the semiconductor body along the sidewall of the trench outside of the trench. The doped sidewall region is in electrical contact with the drain region and forms a vertical drain current path for the transistor.

Vertical DMOS transistor

The present invention is directed to a method for forming multiple active components, such as bipolar transistors, MOSFETs, diodes, etc., on a semiconductor substrate so that active components with higher operation voltage may be formed on a common substrate with a lower operation voltage device and incorporating the existing proven process flow of making the lower operation voltage active components. The present invention is further directed to a method for forming a device of increasing operation voltage over an existing device of same functionality by adding a few steps in the early manufacturing process of the existing device therefore without drastically affecting the device performance.

Semiconductor device integrating high and low voltage devices

A cascoded junction field transistor (JFET) device comprises a first stage high voltage JFET cascoded to a second stage low voltage JFET wherein one of the first and second stages JFET is connected to a drain electrode of another JFET stage.

Cascoded high voltage junction field effect transistor

A transistor includes a semiconductor body; a body region of a first conductivity type formed in the semiconductor body; a gate electrode formed partially overlapping the body region and insulated from the semiconductor body by a gate dielectric layer; a source region of a second conductivity type formed in the body region on a first side of the gate electrode; a trench formed in the semiconductor body on a second side of the gate electrode, the trench being lined with a sidewall dielectric layer and filled with a bottom dielectric layer and a conductive layer above the bottom dielectric layer, the conductive layer being electrically connected to the gate electrode; and a doped sidewall region of the second conductivity type formed in the semiconductor body along the sidewall of the trench where the doped sidewall region forms a vertical drain current path for the transistor.

Aspects of the present disclosure provides a device comprising a P-type semiconductor substrate, an N-type tub above the semiconductor substrate, a P-type region provided in the N-type tub isolated by one or more P-type isolation structures, and an N-type punch-through stopper provided under the P-type regions isolated by the isolation structure(s). The punch-through stopper is heavily doped compared to the N-type tub. The P-type region has a width between the two isolation structures that is equal to or less than that of the N-type punch-through stopper.

Low cost and mask reduction method for high voltage devices

A transistor includes a semiconductor body; a body region of a first conductivity type formed in the semiconductor body; a gate electrode formed partially overlapping the body region and insulated from the semiconductor body by a gate dielectric layer; a source diffusion region of a second conductivity type formed in the body region on a first side of the gate electrode; a trench formed in the semiconductor body on a second side, opposite the first side, of the gate electrode, the trench being lined with a sidewall dielectric layer; and a doped sidewall region of the second conductivity type formed in the semiconductor body along the sidewall of the trench where the doped sidewall region forms a vertical drain current path for the transistor.

One or more Zener diodes and a field effect transistor having a drain connected in series with the one or more Zener diodes are integrally formed by a plurality of doped regions in the same P-type semiconductor substrate and separated by a punch through stop region. An N-type region is formed under the one or more Zener diodes.

Field effect transistor with integrated Zener diode

Method of integrating high voltage devices

A lateral double-diffused metal-oxide-semiconductor (LDMOS) transistor device includes an enhancement implant region formed in a portion of an accumulation region proximate a P-N junction between body and drift drain regions. The enhancement implant region contains additional dopants of the same conductivity type as the drift drain region. There is a gap between the enhancement implant region and the P-N junction. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Growing community of inventors

San Jose, CA, United States of America

Hideaki Tsuchiko