Alpha Omega Semiconductor Inc.

Alpha and Omega Semiconductor (Cayman) Ltd.

Karthik Padmanabhan

Madhur Bobde

Lingpeng Guan

Hamza Yilmaz

Lei Zhang

Bum-Seok Suh

Jian Wang

Daniel S Calafut

Jun Hu

Wenjun Li

Hongyong Xue

Lingbing Chen

Wim Aarts

An apparatus comprising an insulated gate bipolar transistor and a super junction metal-oxide semiconductor field effect transistor wherein the insulated gate bipolar transistor and the super-junction metal-oxide semiconductor field effect transistor are electrically and optionally structurally coupled.

IGBT light load efficiency

A semiconductor device includes a semiconductor body having a base region incorporating a field stop zone where the base region and the field stop zone are both formed using an epitaxial process. Furthermore, the epitaxial layer field stop zone is formed with an enhanced doping profile to realize improved soft-switching performance for the semiconductor device. In some embodiments, the enhanced doping profile includes multiple doped regions with peak doping levels where a first doped region adjacent to a first side of the field stop zone has a first peak doping level that is not higher than a last peak doping level of a last doped region adjacent to the base region. The epitaxial layer field stop zone of the present invention enables complex field stop zone doping profiles to be used to obtain the desired soft-switching characteristics in the semiconductor device.

Semiconductor device incorporating epitaxial layer field stop zone

A method for forming a superjunction power semiconductor device includes forming multiple epitaxial layers of a first conductivity type on a semiconductor substrate and implanting dopants of a second conductivity type into each epitaxial layer to form a first group of implanted regions in a first region and a second group of implanted regions in a second region in each epitaxial layer. The multiple epitaxial layers are annealed to form multiple columns of the second conductivity type having slanted sidewalls across the first to last epitaxial layers. The columns include a first group of columns formed by the implanted regions of the first group and having a first grading and a second group of columns formed by the implanted regions of the second group and having a second grading, where the second grading is less than the first grading.

Method for forming super-junction corner and termination structure with graded sidewalls

Improving IGBT light load efficiency

A superjunction power semiconductor device includes a termination region with superjunction structures having higher breakdown voltage than the breakdown voltage of the active cell region. In one embodiment, the termination region includes superjunction structures having lower column charge as compared to the superjunction structures formed in the active cell region. In other embodiments, a superjunction power semiconductor device incorporating superjunction structures with slanted sidewalls where the grading of the superjunction columns in the termination region is reduced as compared to the column grading in the active cell region. The power semiconductor device is made more robust by ensuring any breakdown occurs in the core region as opposed to the termination region. Furthermore, the manufacturing process window for the power semiconductor device is enhanced to improve the manufacturing yield of the power semiconductor device.

Super-junction corner and termination structure with graded sidewalls

A semiconductor device includes a semiconductor body having a base region incorporating a field stop zone where the base region and the field stop zone are both formed using an epitaxial process. Furthermore, the epitaxial layer field stop zone is formed with an enhanced doping profile to realize improved soft-switching performance for the semiconductor device. In some embodiments, the enhanced doping profile formed in the field stop zone includes varying, non-constant doping levels. In some embodiments, the enhanced doping profile includes one of an extended graded doping profile, a multiple stepped flat doping profile, or a multiple spike doping profile. The epitaxial layer field stop zone of the present invention enables complex field stop zone doping profiles to be used to obtain the desired soft-switching characteristics in the semiconductor device.

An apparatus comprising an insulated gate bipolar transistor; and a super-junction metal-oxide semiconductor field effect transistor wherein the insulated gate bipolar transistor wherein the super-junction metal-oxide semiconductor field effect transistor are structurally coupled and wherein the super-junction metal-oxide semiconductor field effect transistor is configured to switch to an 'on' state from an 'off' state and an &#x2018;off&#x2019; state from an &#x2018;on&#x2019; state.

Combined IGBT and superjunction MOSFET device with tuned switching speed

A semiconductor device includes a superjunction structure formed using simultaneous N and P angled implants into the sidewall of a trench. The simultaneous N and P angled implants use different implant energies and dopants of different diffusion rate so that after annealing, alternating N and P thin semiconductor regions are formed. The alternating N and P thin semiconductor regions form a superjunction structure where a balanced space charge region is formed to enhance the breakdown voltage characteristic of the semiconductor device.

Semiconductor device and method of forming including superjunction structure formed using angled implant process

A trench metal-oxide-semiconductor field-effect transistor (MOSFET) device includes a combination of shielded trench gate structure and a superjunction structure within an epitaxial layer including alternating n-doped and p-doped columns in an a drift region. In one example the gate trenches are formed in and over n-doped columns that have an extra charge region near and adjacent to the lower portion of the corresponding gate trench. The extra charge is balanced due to the shield electrodes in the gate trenches.

SGT superjunction MOSFET structure

Super-junction corner and termination structure with improved breakdown and robustness

A method for forming a lateral superjunction MOSFET device includes forming a semiconductor body including a lateral superjunction structure and a first column connected to the lateral superjunction structure. The MOSFET device includes the first column to receive current from the channel when the MOSFET is turned on and to distribute the channel current to the lateral superjunction structure functioning as the drain drift region. In some embodiment, the MOSFET device includes a second column disposed in close proximity to the first column. The second column disposed near the first column is used to pinch off the first column when the MOSFET device is to be turned off and to block the high voltage being sustained by the MOSFET device at the drain terminal from reaching the gate structure. In some embodiments, the MOSFET device further includes termination structures for the drain, source and body contact doped region fingers.

Method for forming a lateral super-junction MOSFET device and termination  structure

Semiconductor device including superjunction structure formed using angled implant process

Method for forming a lateral super-junction MOSFET device and termination structure

A lateral superjunction MOSFET device includes multiple transistor cells connected to a lateral superjunction structure, each transistor cell including a conductive gate finger, a source region finger, a body contact region finger and a drain region finger arranged laterally within each transistor cell. Each of the drain region fingers, the source region fingers and the body contact region fingers is a doped region finger having a termination region at an end of the doped region finger. The lateral superjunction MOSFET device further includes a termination structure formed in the termination region of each doped region finger and including one or more termination columns having the same conductivity type as the doped region finger and positioned near the end of the doped region finger. The one or more termination columns extend through the lateral superjunction structure and are electrically unbiased.

Lateral super-junction MOSFET device and termination structure

A lateral superjunction MOSFET device includes a gate structure and a first column connected to the lateral superjunction structure. The lateral superjunction MOSFET device includes the first column to receive current from the channel when the MOSFET is turned on and to distribute the channel current to the lateral superjunction structure functioning as the drain drift region. In some embodiment, the MOSFET device includes a second column disposed in close proximity to the first column. The second column disposed near the first column is used to pinch off the first column when the MOSFET device is to be turned off and to block the high voltage being sustained by the MOSFET device at the drain terminal from reaching the gate structure. In some embodiments, the lateral superjunction MOSFET device further includes termination structures for the drain, source and body contact doped region fingers.

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San Jose, CA, United States of America

Karthik Padmanabhan