Patents by Inventor Shengan Xiao

Shengan Xiao 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).

  • Publication number: 20230006037
    Abstract: The present application discloses a super junction device, which includes: an N-type redundant epitaxial layer and an N-type buffer layer sequentially formed on an N-type semiconductor substrate; a trench filled super junction structure is formed on the N-type buffer layer; a back structure includes a drain region and a patterned back P-type impurity region; the N-type semiconductor substrate is removed in a back thinning process, and the N-type redundant epitaxial layer is completely or partially removed in the back thinning process; the resistivity of the N-type semiconductor substrate is 0.1-10 times the resistivity of a top epitaxial layer, the resistivity of the N-type redundant epitaxial layer is 0.1-10 times the resistivity of the N-type semiconductor substrate, and the resistivity of the N-type redundant epitaxial layer is lower than the resistivity of the N-type buffer layer. The present application further discloses a method for manufacturing a super junction device.
    Type: Application
    Filed: January 20, 2022
    Publication date: January 5, 2023
    Applicant: Shenzhen Sanrise-Tech Co., LTD
    Inventors: Shengan Xiao, Dajie Zeng
  • Publication number: 20230006036
    Abstract: The present application discloses a super junction device, comprising: an N-type redundant epitaxial layer and an N-type buffer layer sequentially formed on an N-type semiconductor substrate; wherein a trench-filling super junction structure is formed on the N-type buffer layer; a backside structure of the super junction device comprises a drain region; the N-type semiconductor substrate is removed in a backside thinning process, and the N-type redundant epitaxial layer is completely or partially removed in the backside thinning process; the resistivity of the N-type semiconductor substrate is 0.1-10 times the resistivity of a top epitaxial layer; the resistivity of the N-type redundant epitaxial layer is 0.1-10 times the resistivity of the N-type semiconductor substrate, and the resistivity of the N-type redundant epitaxial layer is lower than the resistivity of the N-type buffer layer. The present application further discloses a method for manufacturing a super junction device.
    Type: Application
    Filed: January 14, 2022
    Publication date: January 5, 2023
    Applicant: Shenzhen Sanrise-Tech Co., LTD
    Inventors: Shengan Xiao, Dajie Zeng
  • Patent number: 9123803
    Abstract: A semiconductor device includes: a P+ substrate; a P? epitaxial layer over the P+ substrate; a P-well and an N? drift region in the P? epitaxial layer and laterally adjacent to each other; an N+ source region in the P-well and connected to a front-side metal via a first contact electrode; an N+ drain region in the N? drift region and connected to the front-side metal via a second contact electrode; a gate structure on the P? epitaxial layer and connected to the front-side metal via a third contact electrode; and a metal plug through the P? epitaxial layer and having one end in contact with the P+ substrate and the other end connected to the front-side metal, the metal plug being adjacent to one side of the N+ source region that is farther from the N? drift region. A method for fabricating the semiconductor device is also disclosed.
    Type: Grant
    Filed: August 16, 2013
    Date of Patent: September 1, 2015
    Assignee: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan Xiao
  • Patent number: 9000516
    Abstract: A super-junction device including a unit region is disclosed. The unit region includes a heavily doped substrate; a first epitaxial layer over the heavily doped substrate; a second epitaxial layer over the first epitaxial layer; a plurality of first trenches in the second epitaxial layer; an oxide film in each of the plurality of first trenches; and a pair of first films on both sides of each of the plurality of first trenches, thereby forming a sandwich structure between every two adjacent ones of the plurality of first trenches, the sandwich structure including two first films and a second film sandwiched therebetween, the second film being formed of a portion of the second epitaxial layer between the two first films of a sandwich structure. A method of forming a super-junction device is also disclosed.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: April 7, 2015
    Assignee: Shanghai Hua Hong NEC Electronics Co., Ltd.
    Inventor: Shengan Xiao
  • Patent number: 8907421
    Abstract: A superjunction structure with unevenly doped P-type pillars (4) and N-type pillars (2a) is disclosed. The N-type pillars (2a) have uneven impurity concentrations in the vertical direction and the P-type pillars (4) have two or more impurity concentrations distributed both in the vertical and lateral directions to ensure that the total quantity of P-type impurities in the P-type pillars (4) close to the substrate (8) is less than that of N-type impurities in the N-type pillars close to the substrate; the total quantity of P-type impurities in the P-type pillars close to the top of the device is greater than that of N-type impurities in the N-type pillars close to the top. A superjunction MOS transistor and manufacturing method of the same are also disclosed. The superjunction structure can improve the capability of sustaining current-surge of a device without affecting or may even reduce the on-resistance of the device.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: December 9, 2014
    Assignee: Shanghai Hua Hong NEC Electronics Co., Ltd.
    Inventor: Shengan Xiao
  • Patent number: 8779423
    Abstract: A method is provided for fabricating a semiconductor structure. The method includes providing a semiconductor substrate, forming an epitaxial layer on a top surface of the semiconductor substrate and having a predetermined thickness, and forming a plurality of trenches in the epitaxial layer. The trenches are formed in the epitaxial layer and have a predetermined depth, top width, and bottom width. Further, the method includes performing a first trench filling process to form a semiconductor layer inside of the trenches using a mixture gas containing at least silicon source gas and halogenoid gas, stopping the first trench filling process when at least one trench is not completely filled, and performing a second trench filling process, different from the first trench filling process, to fill the plurality of trenches completely.
    Type: Grant
    Filed: October 16, 2012
    Date of Patent: July 15, 2014
    Assignee: Shanghai Hua Hong Nec Electronics Company, Limited
    Inventors: Jiquan Liu, Shengan Xiao, Wei Ji
  • Patent number: 8716111
    Abstract: A method for manufacturing trench type super junction device is disclosed. The method includes the step of forming one or more P type implantation regions in the N type epitaxial layer below the bottom of each trench. By using this method, a super junction device having alternating P type and N type regions is produced, wherein the P type region is formed by P type silicon filled in the trench and P type implantation regions below the trench. The present invention can greatly improve the breakdown voltage of a super junction MOSFET.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: May 6, 2014
    Assignee: Shanghai Hua Hong Electronics Co., Ltd.
    Inventors: Fei Wang, Shengan Xiao, Wensheng Qian
  • Publication number: 20140061783
    Abstract: A super-junction device including a unit region is disclosed. The unit region includes a heavily doped substrate; a first epitaxial layer over the heavily doped substrate; a second epitaxial layer over the first epitaxial layer; a plurality of first trenches in the second epitaxial layer; an oxide film in each of the plurality of first trenches; and a pair of first films on both sides of each of the plurality of first trenches, thereby forming a sandwich structure between every two adjacent ones of the plurality of first trenches, the sandwich structure including two first films and a second film sandwiched therebetween, the second film being formed of a portion of the second epitaxial layer between the two first films of a sandwich structure. A method of forming a super-junction device is also disclosed.
    Type: Application
    Filed: September 5, 2013
    Publication date: March 6, 2014
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan Xiao
  • Publication number: 20140048878
    Abstract: A semiconductor device includes: a P+ substrate; a P? epitaxial layer over the P+ substrate; a P-well and an N? drift region in the P? epitaxial layer and laterally adjacent to each other; an N+ source region in the P-well and connected to a front-side metal via a first contact electrode; an N+ drain region in the N? drift region and connected to the front-side metal via a second contact electrode; a gate structure on the P? epitaxial layer and connected to the front-side metal via a third contact electrode; and a metal plug through the P? epitaxial layer and having one end in contact with the P+ substrate and the other end connected to the front-side metal, the metal plug being adjacent to one side of the N+ source region that is farther from the N? drift region. A method for fabricating the semiconductor device is also disclosed.
    Type: Application
    Filed: August 16, 2013
    Publication date: February 20, 2014
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan Xiao
  • Patent number: 8653586
    Abstract: A superjunction device is disclosed, wherein P-type regions in an active region are not in contact with the N+ substrate, and the distance between the surface of the N+ substrate and the bottom of the P-type regions in the active region is greater than the thickness of a transition region in the N-type epitaxial layer. Methods for manufacturing the superjunction device are also disclosed. The present invention is capable of improving the uniformity of reverse breakdown voltage and overshoot current handling capability in a superjunction device.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: February 18, 2014
    Assignee: Shanghai Hua Hong Nec Electronics Co., Ltd.
    Inventor: Shengan Xiao
  • Publication number: 20140042522
    Abstract: A radio frequency (RF) laterally diffused metal oxide semiconductor (LDMOS) device includes a substrate, a p-type epitaxial layer, a p-type well, a lightly doped n-type drain region, a gate oxide layer, a polysilicon gate, a dielectric layer and a Faraday shield. The Faraday shield includes: a horizontal portion covering a portion of the polysilicon gate and isolated from the polysilicon gate by the dielectric layer; a step-like portion with at least two steps covering a portion of the lightly doped n-type drain region and isolated from the lightly doped n-type drain region by the dielectric layer; and a vertical portion connecting the horizontal portion with the step-like portion and isolated from the polysilicon gate and the lightly doped n-type drain region by the dielectric layer. A method of fabricating such an RF LDMOS device is also disclosed.
    Type: Application
    Filed: August 12, 2013
    Publication date: February 13, 2014
    Applicant: SHANGHAI HUA HONG NEC ELECTONICS CO, LTD.
    Inventors: Juanjuan Li, Shengan Xiao, Wensheng Qian, Feng Han, Pengliang Ci
  • Patent number: 8546882
    Abstract: A terminal structure for superjunction device is disclosed. The terminal structure comprises from inside out at least one P type implantation ring and several P type trench rings formed in an N type epitaxial layer to form alternating P type and N type regions. A channel cut-off ring is formed at the border of the device. The P type implantation ring is formed adjacent to the active area of the device and covers at least one trench ring. A terminal dielectric layer is formed to cover the P type implantation ring and the trench rings. A plurality of field plates are formed above the terminal dielectric layer. Methods of manufacturing terminal structure are also disclosed.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: October 1, 2013
    Assignee: Shanghai Hua Hong NEC Electronics Co., Ltd.
    Inventors: Shengan Xiao, Fei Wang, Yanping Liu
  • Publication number: 20130234201
    Abstract: A field stop structure is disclosed. The field stop structure is divided into a three-dimensional structure by a plurality of trenches formed on a back side of a silicon substrate and hence obtains a greater formation depth in the substrate and can achieve a higher ion activation efficiency. Moreover, a first electrode region of a fast recovered diode (FRD) is formed in the trenches, thereby enabling the integration of a FRD with an insulated gate bipolar transistor (IGBT) device. Methods for forming field stop structure and reverse conducting IGBT semiconductor device are also disclosed.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 12, 2013
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan Xiao
  • Publication number: 20130105796
    Abstract: A method is provided for fabricating a semiconductor structure. The method includes providing a semiconductor substrate, forming an epitaxial layer on a top surface of the semiconductor substrate and having a predetermined thickness, and forming a plurality of trenches in the epitaxial layer. The trenches are formed in the epitaxial layer and have a predetermined depth, top width, and bottom width. Further, the method includes performing a first trench filling process to form a semiconductor layer inside of the trenches using a mixture gas containing at least silicon source gas and halogenoid gas, stopping the first trench filling process when at least one trench is not completely filled, and performing a second trench filling process, different from the first trench filling process, to fill the plurality of trenches completely.
    Type: Application
    Filed: October 16, 2012
    Publication date: May 2, 2013
    Inventors: JIQUAN LIU, SHENGAN XIAO, WEI JI
  • Publication number: 20130082323
    Abstract: A superjunction structure with unevenly doped P-type pillars (4) and N-type pillars (2a) is disclosed. The N-type pillars (2a) have uneven impurity concentrations in the vertical direction and the P-type pillars (4) have two or more impurity concentrations distributed both in the vertical and lateral directions to ensure that the total quantity of P-type impurities in the P-type pillars (4) close to the substrate (8) is less than that of N-type impurities in the N-type pillars close to the substrate; the total quantity of P-type impurities in the P-type pillars close to the top of the device is greater than that of N-type impurities in the N-type pillars close to the top. A superjunction MOS transistor and manufacturing method of the same are also disclosed. The superjunction structure can improve the capability of sustaining current-surge of a device without affecting or may even reduce the on-resistance of the device.
    Type: Application
    Filed: September 10, 2012
    Publication date: April 4, 2013
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan Xiao
  • Publication number: 20120326226
    Abstract: A superjunction device is disclosed, wherein P-type regions in an active region are not in contact with the N+ substrate, and the distance between the surface of the N+ substrate and the bottom of the P-type regions in the active region is greater than the thickness of a transition region in the N-type epitaxial layer. Methods for manufacturing the superjunction device are also disclosed. The present invention is capable of improving the uniformity of reverse breakdown voltage and overshoot current handling capability in a superjunction device.
    Type: Application
    Filed: September 5, 2012
    Publication date: December 27, 2012
    Applicant: SHANGHAI HUA HONG NEC ELECTRONICS CO., LTD.
    Inventor: Shengan XIAO
  • Patent number: 8273664
    Abstract: A method of etching and tilling deep trenches is disclosed, which includes: forming an ONO(oxide-nitride-oxide) sandwich layer on a semiconductor substrate; forming deep trenches by using top oxide of the sandwich layer as a stop layer; removing the top oxide and middle SiN of the sandwich layer; tilling the deep trenches with epitaxial film or polysilicon film; polishing the wafer to get a planarized surface by stopping at the surface of the bottom oxide layer; removing the bottom oxide layer.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: September 25, 2012
    Assignee: Shanghai Hua Hong NEC Electronics Co., Ltd.
    Inventors: Xiaohua Cheng, Shengan Xiao
  • Patent number: 8178409
    Abstract: The invention is related to a semiconductor device with alternately arranged P-type and N-type thin semiconductor layers and method for manufacturing the same. For P-type device, the method includes trench formation, thermal oxide formation on trench sidewalls, N-type silicon formation in trenches, N-type impurity diffusion through thermal oxide into P-type epitaxial layer, oxidation of N-type silicon in trenches and oxide removal. In the semiconductor device, N-type thin semiconductor layers are formed by N-type impurity diffusion through oxide to P-type epitaxial layers, and trenches are filled with oxide. With this method, relatively low concentration impurity in high voltage device can be realized by current mass production process, and the device development cost and manufacturing cost are decreased.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: May 15, 2012
    Assignee: Shanghai Hua Hong Nec Electronics Company, Limited
    Inventors: Shengan Xiao, Feng Han
  • Publication number: 20110316121
    Abstract: A method for manufacturing trench type super junction device is disclosed. The method includes the step of forming one or more P type implantation regions in the N type epitaxial layer below the bottom of each trench. By using this method, a super junction device having alternating P type and N type regions is produced, wherein the P type region is formed by P type silicon filled in the trench and P type implantation regions below the trench. The present invention can greatly improve the breakdown voltage of a super junction MOSFET.
    Type: Application
    Filed: June 23, 2011
    Publication date: December 29, 2011
    Inventors: Fei Wang, Shengan Xiao, Wensheng Qian
  • Publication number: 20110306189
    Abstract: A method of etching and tilling deep trenches is disclosed, which includes: forming an ONO(oxide-nitride-oxide) sandwich layer on a semiconductor substrate; forming deep trenches by using top oxide of the sandwich layer as a stop layer; removing the top oxide and middle SiN of the sandwich layer; tilling the deep trenches with epitaxial film or polysilicon film; polishing the wafer to get a planarized surface by stopping at the surface of the bottom oxide layer; removing the bottom oxide layer.
    Type: Application
    Filed: June 8, 2011
    Publication date: December 15, 2011
    Inventors: Xiaohua Cheng, Shengan Xiao