Patents by Inventor Shahaji B. More

Shahaji B. More 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: 10535736
    Abstract: The present disclosure describes an exemplary method to form p-type fully strained channel (PFSC) or an n-type fully strained channel (NFSC) that can mitigate epitaxial growth defects or structural deformations in the channel region due to processing. The exemplary method can include (i) two or more surface pre-clean treatment cycles with nitrogen trifluoride (NF3) and ammonia (NH3) plasma, followed by a thermal treatment; (ii) a prebake (anneal); and (iii) a silicon germanium epitaxial growth with a silicon seed layer, a silicon germanium seed layer, or a combination thereof.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: January 14, 2020
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. More, Huai-Tei Yang, Zheng-Yang Pan, Shih-Chieh Chang, Chun-Chieh Wang, Cheng-Han Lee
  • Patent number: 10522358
    Abstract: A FinFET device and method of forming the same are disclosed. The method includes forming a gate dielectric layer and depositing a metal oxide layer over the gate dielectric layer. The method also includes annealing the gate dielectric layer and the metal oxide layer, causing ions to diffuse from the metal oxide layer to the gate dielectric layer to form a doped gate dielectric layer. The method also includes forming a work function layer over the doped gate dielectric layer, and forming a gate electrode over the work function layer.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: December 31, 2019
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chun-Chieh Wang, Zheng-Yang Pan, Shih-Chieh Chang, Cheng-Han Lee, Huai-Tei Yang, Shahaji B. More
  • Patent number: 10510889
    Abstract: In certain embodiments, a semiconductor device includes a substrate having an n-doped well feature and an epitaxial silicon germanium fin formed over the n-doped well feature. The epitaxial silicon germanium fin has a lower part and an upper part. The lower part has a lower germanium content than the upper part. A channel is formed from the epitaxial silicon germanium fin. A gate is formed over the epitaxial silicon germanium fin. A doped source-drain is formed proximate the channel.
    Type: Grant
    Filed: March 15, 2018
    Date of Patent: December 17, 2019
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. More, Huai-Tei Yang, Shih-Chieh Chang, Shu Kuan, Cheng-Han Lee
  • Patent number: 10510871
    Abstract: Methods are disclosed for forming a multi-layer structure including highly controlled diffusion interfaces between alternating layers of different semiconductor materials. According to embodiments, during a deposition of semiconductor layers, the process is controlled to remain at low temperatures such that an inter-diffusion rate between the materials of the deposited layers is managed to provide diffusion interfaces with abrupt Si/SiGe interfaces. The highly controlled interfaces and first and second layers provide a multi-layer structure with improved etching selectivity. In an embodiment, a gate all-around (GAA) transistor is formed with horizontal nanowires (NWs) from the multi-layer structure with improved etching selectivity. In embodiments, horizontal NWs of a GAA transistor may be formed with substantially the same size diameters and silicon germanium (SiGe) NWs may be formed with “all-in-one” silicon (Si) caps.
    Type: Grant
    Filed: August 16, 2018
    Date of Patent: December 17, 2019
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Shahaji B. More, Shih-Chieh Chang
  • Publication number: 20190363176
    Abstract: Methods for forming semiconductor structures are provided. The method includes forming a fin structure over a substrate and forming a gate structure across the fin structure. The method further includes recessing the fin structure to form a recess and implanting dopants from the recess to form a doped region. The method further includes diffusing the dopants in the doped region to form an expanded doped region and forming a source/drain structure over the expanded doped region.
    Type: Application
    Filed: July 19, 2019
    Publication date: November 28, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. MORE, Chun-Hsiung TSAI, Cheng-Yi PENG, Shih-Chieh CHANG, Kuo-Feng YU
  • Patent number: 10468500
    Abstract: A method and structure for doping source and drain (S/D) regions of a PMOS and/or NMOS FinFET device are provided. In some embodiments, a method includes providing a substrate including a fin extending therefrom. In some examples, the fin includes a channel region, source/drain regions disposed adjacent to and on either side of the channel region, a gate structure disposed over the channel region, and a main spacer disposed on sidewalls of the gate structure. In some embodiments, contact openings are formed to provide access to the source/drain regions, where the forming the contact openings may etch a portion of the main spacer. After forming the contact openings, a spacer deposition and etch process may be performed. In some cases, after performing the spacer deposition and etch process, a silicide layer is formed over, and in contact with, the source/drain regions.
    Type: Grant
    Filed: June 29, 2018
    Date of Patent: November 5, 2019
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Chun Hsiung Tsai, Cheng-Yi Peng, Yin-Pin Wang, Kuo-Feng Yu, Da-Wen Lin, Jian-Hao Chen, Shahaji B. More
  • Publication number: 20190334029
    Abstract: A method includes providing a substrate having a gate structure over a first side of the substrate, forming a recess adjacent to the gate structure, and forming in the recess a first semiconductor layer having a dopant, the first semiconductor layer being non-conformal, the first semiconductor layer lining the recess and extending from a bottom of the recess to a top of the recess. The method further includes forming a second semiconductor layer having the dopant in the recess and over the first semiconductor layer, a second concentration of the dopant in the second semiconductor layer being higher than a first concentration of the dopant in the first semiconductor layer.
    Type: Application
    Filed: July 8, 2019
    Publication date: October 31, 2019
    Inventors: Chih-Yu Ma, Zheng-Yang Pan, Shahaji B. More, Shih-Chieh Chang, Cheng-Han Lee
  • Publication number: 20190288067
    Abstract: A semiconductor device includes a substrate, an isolation structure over the substrate, a fin over the substrate and the isolation structure, a gate structure engaging a first portion of the fin, first sidewall spacers over sidewalls of the gate structure and over a second portion of the fin, source/drain (S/D) features adjacent to the first sidewall spacers, and second sidewall spacers over the isolation structure and over sidewalls of a portion of the S/D features. The second sidewall spacers and the second portion of the fin include a same dopant.
    Type: Application
    Filed: May 23, 2019
    Publication date: September 19, 2019
    Inventors: Chun Hsiung Tsai, Ya-Yun Cheng, Shahaji B. More, Cheng-Yi Peng, Wei-Yang Lee, Kuo-Feng Yu, Yen-Ming Chen, Jian-Hao Chen
  • Patent number: 10396156
    Abstract: A method includes providing a structure having a substrate, a fin, and a gate structure; performing an implantation process to implant a dopant into the fin adjacent to the gate structure; and forming gate sidewall spacers and fin sidewall spacers. The method further includes performing a first etching process to recess the fin adjacent to the gate sidewall spacers while keeping at least a portion of the fin above the fin sidewall spacers. The method further includes performing another implantation process to implant the dopant into the fin and the fin sidewall spacers; and performing a second etching process to recess the fin adjacent to the gate sidewall spacers until a top surface of the fin is below a top surface of the fin sidewall spacers, resulting in a trench between the fin sidewall spacers. The method further includes epitaxially growing a semiconductor material in the trench.
    Type: Grant
    Filed: January 29, 2018
    Date of Patent: August 27, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.
    Inventors: Chun Hsiung Tsai, Ya-Yun Cheng, Shahaji B. More, Cheng-Yi Peng, Wei-Yang Lee, Kuo-Feng Yu, Yen-Ming Chen, Jian-Hao Chen
  • Publication number: 20190244864
    Abstract: A semiconductor device and method includes: forming a gate stack over a substrate; growing a source/drain region adjacent the gate stack, the source/drain region being n-type doped Si; growing a semiconductor cap layer over the source/drain region, the semiconductor cap layer having Ge impurities, the source/drain region free of the Ge impurities; depositing a metal layer over the semiconductor cap layer; annealing the metal layer and the semiconductor cap layer to form a silicide layer over the source/drain region, the silicide layer having the Ge impurities; and forming a metal contact electrically coupled to the silicide layer.
    Type: Application
    Filed: April 22, 2019
    Publication date: August 8, 2019
    Inventors: Shahaji B. More, Zheng-Yang Pan, Cheng-Han Lee, Shih-Chieh Chang
  • Publication number: 20190237543
    Abstract: A method includes providing a structure having a substrate, a fin, and a gate structure; performing an implantation process to implant a dopant into the fin adjacent to the gate structure; and forming gate sidewall spacers and fin sidewall spacers. The method further includes performing a first etching process to recess the fin adjacent to the gate sidewall spacers while keeping at least a portion of the fin above the fin sidewall spacers. The method further includes performing another implantation process to implant the dopant into the fin and the fin sidewall spacers; and performing a second etching process to recess the fin adjacent to the gate sidewall spacers until a top surface of the fin is below a top surface of the fin sidewall spacers, resulting in a trench between the fin sidewall spacers. The method further includes epitaxially growing a semiconductor material in the trench.
    Type: Application
    Filed: January 29, 2018
    Publication date: August 1, 2019
    Inventors: Chun Hsiung Tsai, Ya-Yun Cheng, Shahaji B. More, Cheng-Yi Peng, Wei-Yang Lee, Kuo-Feng Yu, Yen-Ming Chen, Jian-Hao Chen
  • Patent number: 10361279
    Abstract: Methods for forming semiconductor structures are provided. The method includes forming a fin structure over a substrate and forming a gate structure across the fin structure. The method further includes forming a fin spacer on a sidewall of the fin structure and partially removing the fin spacer. The method further includes recessing the fin structure to form a recess and implanting dopants from the recess to form a doped region. The method further includes diffusing the dopants in the doped region to form an expanded doped region and forming a source/drain structure over the expanded doped region.
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: July 23, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.
    Inventors: Shahaji B. More, Chun-Hsiung Tsai, Cheng-Yi Peng, Shih-Chieh Chang, Kuo-Feng Yu
  • Patent number: 10347764
    Abstract: A method includes providing a substrate having a gate structure over a first side of the substrate, forming a recess adjacent to the gate structure, and forming in the recess a first semiconductor layer having a dopant, the first semiconductor layer being non-conformal, the first semiconductor layer lining the recess and extending from a bottom of the recess to a top of the recess. The method further includes forming a second semiconductor layer having the dopant in the recess and over the first semiconductor layer, a second concentration of the dopant in the second semiconductor layer being higher than a first concentration of the dopant in the first semiconductor layer.
    Type: Grant
    Filed: October 5, 2017
    Date of Patent: July 9, 2019
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chih-Yu Ma, Zheng-Yang Pan, Shahaji B. More, Shih-Chieh Chang, Cheng-Han Lee
  • Publication number: 20190165143
    Abstract: Methods for forming semiconductor structures are provided. The method includes forming a fin structure over a substrate and forming a gate structure across the fin structure. The method further includes forming a fin spacer on a sidewall of the fin structure and partially removing the fin spacer. The method further includes recessing the fin structure to form a recess and implanting dopants from the recess to form a doped region. The method further includes diffusing the dopants in the doped region to form an expanded doped region and forming a source/drain structure over the expanded doped region.
    Type: Application
    Filed: May 31, 2018
    Publication date: May 30, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. MORE, Chun-Hsiung TSAI, Cheng-Yi PENG, Shih-Chieh CHANG, Kuo-Feng YU
  • Publication number: 20190165124
    Abstract: A semiconductor structure includes a substrate, a semiconductor fin connected to the substrate, an epitaxial layer disposed over the semiconductor fin, and a silicide feature over and in contact with the epitaxial layer. The epitaxial layer including silicon germanium (SiGe) and further includes gallium (Ga) in an upper portion of the epitaxial layer that is in contact with the silicide feature.
    Type: Application
    Filed: December 6, 2018
    Publication date: May 30, 2019
    Inventors: Shahaji B. More, Chun Hsiung Tsai, Shih-Chieh Chang, Kuo-Feng Yu, Cheng-Yi Peng
  • Publication number: 20190165175
    Abstract: In certain embodiments, a semiconductor device includes a substrate having an n-doped well feature and an epitaxial silicon germanium fin formed over the n-doped well feature. The epitaxial silicon germanium fin has a lower part and an upper part. The lower part has a lower germanium content than the upper part. A channel is formed from the epitaxial silicon germanium fin. A gate is formed over the epitaxial silicon germanium fin. A doped source-drain is formed proximate the channel.
    Type: Application
    Filed: March 15, 2018
    Publication date: May 30, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. MORE, Huai-Tei YANG, Shih-Chieh CHANG, Shu KUAN, Cheng-Han LEE
  • Publication number: 20190157154
    Abstract: The present disclosure describes an exemplary fabrication method of a p-type fully strained channel that can suppress the formation of {111} facets during a silicon germanium epitaxial growth. The exemplary method includes the formation of silicon epitaxial layer on a top, carbon-doped region of an n-type region. A recess is formed in the silicon epitaxial layer via etching, where the recess exposes the top, carbon-doped region of the n-type region. A silicon seed layer is grown in the recess, and a silicon germanium layer is subsequently epitaxially grown on the silicon seed layer to fill the recess. The silicon seed layer can suppress the formation of growth defects such as, for example, {111} facets, during the silicon germanium epitaxial layer growth.
    Type: Application
    Filed: November 21, 2017
    Publication date: May 23, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Chun-Chieh Wang, Huai-Tei Yang, Zheng-Yang Pan, Shahaji B. More, Shih-Chieh Chang, Cheng-Han Lee
  • Publication number: 20190148551
    Abstract: The present disclosure describes a method to form silicon germanium (SiGe) source/drain epitaxial stacks with a boron doping profile and a germanium concentration that can induce external stress to a fully strained SiGe channel. The method includes forming one or more gate structures over a fin, where the fin includes a fin height, a first sidewall, and a second sidewall opposite to the first sidewall. The method also includes forming a first spacer on the first sidewall of the fin and a second spacer on the second sidewall of the fin; etching the fin to reduce the fin height between the one or more gate structures; and etching the first spacer and the second spacer between the one or more gate structures so that the etched first spacer is shorter than the etched second spacer and the first and second etched spacers are shorter than the etched fin. The method further includes forming an epitaxial stack on the etched fin between the one or more gate structures.
    Type: Application
    Filed: June 4, 2018
    Publication date: May 16, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd
    Inventors: Shahaji B. MORE, Huai-Tei Yang, Shih-Chieh Chang, Cheng-Han Lee
  • Publication number: 20190148527
    Abstract: Semiconductor structures and method for forming the same are provide. The method includes forming a gate structure over a substrate and forming a recess in the substrate adjacent to the gate structure. The method further includes forming a doped region at a sidewall and a bottom surface of the recess and partially removing the doped region to modify a shape of the recess. The method further includes forming a source/drain structure over a remaining portion of the doped region.
    Type: Application
    Filed: April 25, 2018
    Publication date: May 16, 2019
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Shahaji B. MORE, Shih-Chieh CHANG, Cheng-Han LEE, Huai-Tei YANG
  • Publication number: 20190148552
    Abstract: A method for forming a semiconductor device is provided. The method includes forming a gate stack to partially cover a semiconductor structure. The method also includes forming a first semiconductor material over the semiconductor structure. The method further includes forming a second semiconductor material over the first semiconductor material. In addition, the method includes forming a third semiconductor material over the second semiconductor material. The first semiconductor material and the third semiconductor material together surround the second semiconductor material. The second semiconductor material has a greater dopant concentration than that of the first semiconductor material or that of the third semiconductor material.
    Type: Application
    Filed: December 24, 2018
    Publication date: May 16, 2019
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.
    Inventors: Shahaji B. MORE, Zheng-Yang PAN, Chun-Chieh WANG, Cheng-Han LEE, Shih-Chieh CHANG