Patents by Inventor Tien Chan

Tien Chan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7276431
    Abstract: An structure for electrically isolating a semiconductor device is formed by implanting dopant into a semiconductor substrate that does not include an epitaxial layer. Following the implant the structure is exposed to a very limited thermal budget so that dopant does not diffuse significantly. As a result, the dimensions of the isolation structure are limited and defined, thereby allowing a higher packing density than obtainable using conventional processes which include the growth of an epitaxial layer and diffusion of the dopants. In one group of embodiments, the isolation structure includes a deep layer and a sidewall which together form a cup-shaped structure surrounding an enclosed region in which the isolated semiconductor device may be formed. The sidewalls may be formed by a series of pulsed implants at different energies, thereby creating a stack of overlapping implanted regions.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: October 2, 2007
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7265434
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: September 4, 2007
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7211863
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: May 1, 2007
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7202536
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: April 10, 2007
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20070044427
    Abstract: A cleaning machine operated under water to clean radioactive particles on surfaces of nuclear wastes of middle-high activity to reduce activity, and to prevent radiation from leaking out when cleaning the nuclear wastes.
    Type: Application
    Filed: August 26, 2005
    Publication date: March 1, 2007
    Inventors: Kuo-Chi Lan, Tien-Chan Chang, Yu-Tang Yang, Chun-Ming Wu
  • Patent number: 7176548
    Abstract: A semiconductor substrate includes a pair of trenches filled with a dielectric material. Dopant introduced into the mesa between the trenches is limited from diffusing laterally when the substrate is subjected to thermal processing. Therefore, semiconductor devices can be spaced more closely together on the substrate, and the packing density of the devices can be increased. Also trench constrained doped region diffuse faster and deeper than unconstrained diffusions, thereby reducing the time and temperature needed to complete a desired depth diffusion. The technique may be used for semiconductor devices such as bipolar transistors as well as isolation regions that electrically isolate the devices from each other. In one group of embodiments, a buried layer is formed at an interface between an epitaxial layer and a substrate, at a location generally below the dopant in the mesa.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: February 13, 2007
    Assignee: Advanced Analogic Technologies, Inc
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7135738
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: November 14, 2006
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7084456
    Abstract: In a trench-gated MOSFET including an epitaxial layer over a substrate of like conductivity and trenches containing thick bottom oxide, sidewall gate oxide, and conductive gates, body regions of the complementary conductivity are shallower than the gates, and clamp regions are deeper and more heavily doped than the body regions but shallower than the trenches. Zener junctions clamp a drain-source voltage lower than the FPI breakdown of body junctions near the trenches, but the zener junctions, being shallower than the trenches, avoid undue degradation of the maximum drain-source voltage. The epitaxial layer may have a dopant concentration that increases step-wise or continuously with depth. Chained implants of the body and clamp regions permits accurate control of dopant concentrations and of junction depth and position. Alternative fabrication processes permit implantation of the body and clamp regions before gate bus formation or through the gate bus after gate bus formation.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: August 1, 2006
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 7075145
    Abstract: Power MOSFETs and fabrication processes for power MOSFETs use a continuous conductive gate structure within trenches to avoid problems arising from device topology caused when a gate bus extends above a substrate surface. The gate bus trench and/or gate structures in the device trenches can contain a metal/silicide to reduce resistance, where polysilicon layers surround the metal/silicide to prevent metal atoms from penetrating the gate oxide in the device trenches. CMP process can remove excess polysilicon and metal and planarize the conductive gate structure and/or overlying insulating layers. The processes are compatible with processes forming self-aligned or conventional contacts in the active device region.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: July 11, 2006
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 6969888
    Abstract: Power MOSFETs and fabrication processes for power MOSFETs use a continuous conductive gate structure within trenches to avoid problems arising from device topology caused when a gate bus extends above a substrate surface. The gate bus trench and/or gate structures in the device trenches can contain a metal/silicide to reduce resistance, where polysilicon layers surround the metal/silicide to prevent metal atoms from penetrating the gate oxide in the device trenches. CMP process can remove excess polysilicon and metal and planarize the conductive gate structure and/or overlying insulating layers. The processes are compatible with processes forming self-aligned or conventional contacts in the active device region.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: November 29, 2005
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 6943426
    Abstract: A semiconductor substrate includes a pair of trenches filled with a dielectric material. Dopant introduced into the mesa between the trenches is limited from diffusing laterally when the substrate is subjected to thermal processing. Therefore, semiconductor devices can be spaced more closely together on the substrate, and the packing density of the devices can be increased. Also trench constrained doped region diffuse faster and deeper than unconstrained diffusions, thereby reducing the time and temperature needed to complete a desired depth diffusion. The technique may be used for semiconductor devices such as bipolar transistors as well as isolation regions that electrically isolate the devices from each other. In one group of embodiments, a buried layer is formed at an interface between an epitaxial layer and a substrate, at a location generally below the dopant in the mesa.
    Type: Grant
    Filed: August 14, 2002
    Date of Patent: September 13, 2005
    Assignee: Advanced Analogic Technologies, Inc.
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20050194643
    Abstract: A semiconductor die has a bonding pad for a MOSFET such as a power MOSFET and a separate bonding pad for ESD protection circuitry. Connecting the bonding pads together makes the ESD protection circuitry functional to protect the MOSFET. Before connecting the bonding pads together, the ESD protection circuitry and/or the MOSFET can be separately tested. A voltage higher than functioning ESD protection circuitry would permit can be used when testing the MOSFET. A packaging process such as wire bonding or attaching the die to a substrate in a flip-chip package can connect the bonding pads after testing.
    Type: Application
    Filed: May 5, 2005
    Publication date: September 8, 2005
    Inventors: Richard Williams, Michael Cornell, Wai Tien Chan
  • Patent number: 6906386
    Abstract: A semiconductor die has a bonding pad for a MOSFET such as a power MOSFET and a separate bonding pad for ESD protection circuitry. Connecting the bonding pads together makes the ESD protection circuitry functional to protect the MOSFET. Before connecting the bonding pads together, the ESD protection circuitry and/or the MOSFET can be separately tested. A voltage higher than functioning ESD protection circuitry would permit can be used when testing the MOSFET. A packaging process such as wire bonding or attaching the die to a substrate in a flip-chip package can connect the bonding pads after testing.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: June 14, 2005
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 6900091
    Abstract: An structure for electrically isolating a semiconductor device is formed by implanting dopant into a semiconductor substrate that does not include an epitaxial layer. Following the implant the structure is exposed to a very limited thermal budget so that dopant does not diffuse significantly. As a result, the dimensions of the isolation structure are limited and defined, thereby allowing a higher packing density than obtainable using conventional processes which include the growth of an epitaxial layer and diffusion of the dopants. In one group of embodiments, the isolation structure includes a deep layer and a sidewall which together form a cup-shaped structure surrounding an enclosed region in which the isolated semiconductor device may be formed. The sidewalls may be formed by a series of pulsed implants at different energies, thereby creating a stack of overlapping implanted regions.
    Type: Grant
    Filed: August 14, 2002
    Date of Patent: May 31, 2005
    Assignee: Advanced Analogic Technologies, Inc.
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 6861701
    Abstract: Power MOSFETs and fabrication processes for power MOSFETs use a continuous conductive gate structure within trenches to avoid problems arising from device topology caused when a gate bus extends above a substrate surface. The conductive gate structure forms gates in device trenches in an active device region and forms a gate bus in a gate bus trench. The gate bus trench that connects to the device trenches can be wide to facilitate forming a gate contact to the gate bus, while the device trenches can be narrow to maximize device density. CMP process can be used to planarize the conductive gate structure and/or overlying insulating layers. The processes are compatible with processes forming self-aligned or conventional contacts in the active device region.
    Type: Grant
    Filed: March 5, 2003
    Date of Patent: March 1, 2005
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Patent number: 6855985
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Grant
    Filed: September 29, 2002
    Date of Patent: February 15, 2005
    Assignees: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20040259318
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Application
    Filed: January 28, 2004
    Publication date: December 23, 2004
    Applicants: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20040251497
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Application
    Filed: January 28, 2004
    Publication date: December 16, 2004
    Applicants: Advanced Analogic Technologies, Inc., Advanced Analogic Technologies (Hong Kong) Limited
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20040183129
    Abstract: Power MOSFETs and fabrication processes for power MOSFETs use a continuous conductive gate structure within trenches to avoid problems arising from device topology caused when a gate bus extends above a substrate surface. The gate bus trench and/or gate structures in the device trenches can contain a metal/silicide to reduce resistance, where polysilicon layers surround the metal/silicide to prevent metal atoms from penetrating the gate oxide in the device trenches. CMP process can remove excess polysilicon and metal and planarize the conductive gate structure and/or overlying insulating layers. The processes are compatible with processes forming self-aligned or conventional contacts in the active device region.
    Type: Application
    Filed: January 29, 2004
    Publication date: September 23, 2004
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan
  • Publication number: 20040183136
    Abstract: Power MOSFETs and fabrication processes for power MOSFETs use a continuous conductive gate structure within trenches to avoid problems arising from device topology caused when a gate bus extends above a substrate surface. The gate bus trench and/or gate structures in the device trenches can contain a metal/silicide to reduce resistance, where polysilicon layers surround the metal/silicide to prevent metal atoms from penetrating the gate oxide in the device trenches. CMP process can remove excess polysilicon and metal and planarize the conductive gate structure and/or overlying insulating layers. The processes are compatible with processes forming self-aligned or conventional contacts in the active device region.
    Type: Application
    Filed: January 29, 2004
    Publication date: September 23, 2004
    Inventors: Richard K. Williams, Michael E. Cornell, Wai Tien Chan