Patents by Inventor Xian-Feng Liu

Xian-Feng Liu 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: 7544558
    Abstract: This invention is forming the DMOS channel after CMOS active layer before gate poly layer to make the modular DMOS process step easily adding into the sub-micron CMOS or BiCMOS process. And DMOS source is formed by implant which is separated by a spacer self-aligned to the window for DMOS body. By this method, the performance of CMOS and bipolar devices formed original CMOS or BiCMOS process keeps no change. The product design kit, such as standard cell library of CMOS and BiCMOS, can be used continuously with no change.
    Type: Grant
    Filed: March 13, 2006
    Date of Patent: June 9, 2009
    Assignee: BCD Semiconductor Manufacturing Limited
    Inventors: Chong Ren, Xian-Feng Liu, Huang Hai Tao
  • Patent number: 7535058
    Abstract: A lateral DMOS structure includes a light doped p-type region beneath and near the gate at the drain side. The electric field on the surface near the gate is reduced. Thus the electric field near the gate decreases, and the SOA (safe operating area) of the lateral DMOS device increases and long time reliability improves. Moreover, the lateral DMOS of the invention can be fabricated without increasing the manufacturing cost.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: May 19, 2009
    Assignee: BCD Semiconductor Manufacturing Limited
    Inventors: Xian-Feng Liu, Chong Ren, Hai-Tao Huang
  • Patent number: 7446012
    Abstract: The present invention relates to a lateral PNP transistor and the method of manufacturing the same. The medium doping N-type base area and the light doping P? collector area were first introduced in the structure before the formation of P+ doping emitter area and the collector area. The emitter-base-collector doping profile in the lateral and the base width of LPNP were similar to NPN. The designer can optimize the doping profile and area size of each area according to the request of the current gain (Hfe), collector-base breakdown voltage (BVceo), and early voltage (VA) of LPNP transistor. These advantages may cause to reduce the area and enhance performance of the LPNP transistor.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: November 4, 2008
    Assignee: BCD Semiconductor Manufacturing Limited
    Inventors: Chong Ren, Xian-Feng Liu, Bin Qiu
  • Publication number: 20070278569
    Abstract: A lateral DMOS structure includes a light doped p-type region beneath and near the gate at the drain side. The electric field on the surface near the gate is reduced. Thus the electric field near the gate decreases, and the SOA (safe operating area) of the lateral DMOS device increases and long time reliability improves. Moreover, the lateral DMOS of the invention can be fabricated without increasing the manufacturing cost.
    Type: Application
    Filed: April 20, 2007
    Publication date: December 6, 2007
    Inventors: Xian-Feng Liu, Chong Ren, Hai-Tao Huang
  • Publication number: 20070212823
    Abstract: This invention is forming the DMOS channel after CMOS active layer before gate poly layer to make the modular DMOS process step easily adding into the sub-micron CMOS or BiCMOS process. And DMOS source is formed by implant which is separated by a spacer self-aligned to the window for DMOS body. By this method, the performance of CMOS and bipolar devices formed original CMOS or BiCMOS process keeps no change. The product design kit, such as standard cell library of CMOS and BiCMOS, can be used continuously with no change.
    Type: Application
    Filed: March 13, 2006
    Publication date: September 13, 2007
    Inventors: Chong Ren, Xian-Feng Liu, Huang Tao
  • Publication number: 20070176254
    Abstract: The present invention discloses a high voltage and high frequency poly emitter bipolar structure with improved breakdown voltage performance. The advantage of the poly emitter bipolar structures is that the SOD coating layer can improve the breakdown voltage of a capacitor structure higher to be 6-8 volts. In addition, the poly emitter bipolar structure having the inter-level dielectric layer deposited by PECVD on the emitter and collector by optimizing PECVD deposition process condition to adjust the charge in the oxide of inter-level dielectric layer has a breakdown voltage higher than 30 volts.
    Type: Application
    Filed: January 30, 2006
    Publication date: August 2, 2007
    Inventors: Xian-Feng Liu, Chong Ren, Jin-Chuan Zeng, Bin Qiu
  • Publication number: 20070173026
    Abstract: The present invention discloses a method for fabricating bipolar integrated circuits, wherein LOCOS technology is used to define the active regions needed by all elements so that the self-alignment of the associated layers can be realized, and implant resistor regions are also directly defined in the active regions by local oxide layers; after base regions have been driven in the wafer, the resistors are implanted into the wafer so that the cost of resistor photomasks can be saved; silicon nitride is adopted to be the material of the dielectric layers of the capacitors, and with the characteristic of a buffering oxide etchant that etches oxide faster than it etches silicon nitride, the conventional deposition sequence of the dielectric layer is changed so that the formation of the dielectric layer needs only a single photomask.
    Type: Application
    Filed: January 23, 2006
    Publication date: July 26, 2007
    Inventors: JinChuan Zeng, Chong Ren, Bin Qiu, Xian-Feng Liu
  • Publication number: 20060118881
    Abstract: The present invention relates to a lateral PNP transistor and the method of manufacturing the same. The medium doping N-type base area and the light doping P? collector area were first introduced in the structure before the formation of P+ doping emitter area and the collector area. The emitter-base-collector doping profile in the lateral and the base width of LPNP were similar to NPN. The designer can optimize the doping profile and area size of each area according to the request of the current gain (Hfe), collector-base breakdown voltage (BVceo), and early voltage (VA) of LPNP transistor. These advantages may cause to reduce the area and enhance performance of the LPNP transistor.
    Type: Application
    Filed: January 20, 2006
    Publication date: June 8, 2006
    Applicant: BCD Semiconductor Manufacturing Limited
    Inventors: Chong Ren, Xian-Feng Liu, Bin Qiu