Patents by Inventor Yi-Shen Wang

Yi-Shen Wang 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: 20200185454
    Abstract: A MTJ stack comprising at least a pinned layer, a barrier layer, and a free layer is deposited on a bottom electrode. A top electrode layer, a carbon-based hard mask, and a dielectric hard mask are deposited in order on the MTJ stack. First, the hard masks and MTJ stack are etched. The etched MTJ stack has a first width. During the first etching, chemical damage forms on sidewalls of the MTJ stack. Next, the carbon-based hard mask is trimmed to a second width smaller than the first width. Then in a second etching, the top electrode and free layer of said MTJ stack not covered by the trimmed carbon-based hard mask are etched to complete formation of the MTJ structure wherein during the second etching of the free layer, chemical damage is removed from the free layer and metal re-deposition is formed on sidewalls of the free layer.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 11, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Patent number: 10680168
    Abstract: A metal layer and first dielectric hard mask are deposited on a bottom electrode. These are patterned and etched to a first pattern size. The patterned metal layer is trimmed using IBE at an angle of 70-90 degrees wherein the metal layer is reduced to a second pattern size smaller than the first pattern size. A dielectric layer is deposited surrounding the patterned metal layer and polished to expose a top surface of the patterned metal layer to form a via connection to the bottom electrode. A MTJ stack is deposited on the dielectric layer and via connection. The MTJ stack is etched to a pattern size larger than the via size wherein an over etching is performed. Re-deposition material is formed on sidewalls of the dielectric layer underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.
    Type: Grant
    Filed: April 6, 2018
    Date of Patent: June 9, 2020
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Yi Yang, Dongna Shen, Zhongjian Teng, Jesmin Haq, Yu-Jen Wang
  • Publication number: 20200144493
    Abstract: A MTJ stack is deposited on a bottom electrode. A metal hard mask is deposited on the MTJ stack and a dielectric mask is deposited on the metal hard mask. A photoresist pattern is formed on the dielectric mask, having a critical dimension of more than about 65 nm. The dielectric and metal hard masks are etched wherein the photoresist pattern is removed. The dielectric and metal hard masks are trimmed to reduce their critical dimension to 10-60 nm and to reduce sidewall surface roughness. The dielectric and metal hard masks and the MTJ stack are etched wherein the dielectric mask is removed and a MTJ device is formed having a small critical dimension of 10-60 nm, and having further reduced sidewall surface roughness.
    Type: Application
    Filed: December 27, 2019
    Publication date: May 7, 2020
    Inventors: Dongna Shen, Yi Yang, Jesmin Haq, Yu-Jen Wang
  • Publication number: 20200136031
    Abstract: A via connection is provided through a dielectric layer to a bottom electrode. A MTJ stack is deposited on the dielectric layer and via connection. A top electrode is deposited on the MTJ stack. A selective hard mask and then a dielectric hard mask are deposited on the top electrode. The dielectric and selective hard masks are patterned and etched. The dielectric and selective hard masks and the top electrode are etched wherein the dielectric hard mask is removed. The top electrode is trimmed using IBE at an angle of 70 to 90 degrees. The selective hard mask, top electrode, and MTJ stack are etched to form a MTJ device wherein over etching into the dielectric layer surrounding the via connection is performed and re-deposition material is formed on sidewalls of the dielectric layer underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.
    Type: Application
    Filed: December 27, 2019
    Publication date: April 30, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20200136021
    Abstract: A method for fabricating a magnetic tunneling junction (MTJ) structure is described. A first dielectric layer is deposited on a bottom electrode and partially etched through to form a first via opening having straight sidewalls, then etched all the way through to the bottom electrode to form a second via opening having tapered sidewalls. A metal layer is deposited in the second via opening and planarized to the level of the first dielectric layer. The remaining first dielectric layer is removed leaving an electrode plug on the bottom electrode. MTJ stacks are deposited on the electrode plug and on the bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and polished to expose a top surface of the MTJ stack on the electrode plug. A top electrode layer is deposited to complete the MTJ structure.
    Type: Application
    Filed: December 27, 2019
    Publication date: April 30, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20200119264
    Abstract: A MTJ stack is deposited on a bottom electrode. A top electrode layer and hard mask are deposited on the MTJ stack. The top electrode layer not covered by the hard mask is etched. Thereafter, a first spacer layer is deposited over the patterned top electrode layer and the hard mask. The first spacer layer is etched away on horizontal surfaces leaving first spacers on sidewalls of the patterned top electrode layer. The free layer not covered by the hard mask and first spacers is etched. Thereafter, the steps of depositing a subsequent spacer layer over patterned previous layers, etching away the subsequent spacer layer on horizontal surfaces leaving subsequent spacers on sidewalls of the patterned previous layers, and thereafter etching a next layer not covered by the hard mask and subsequent spacers are repeated until all layers of the MTJ stack have been etched to complete the MTJ structure.
    Type: Application
    Filed: December 17, 2019
    Publication date: April 16, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20200111791
    Abstract: A method of forming a layout of a semiconductor device includes the following steps. First line patterns extend along a first direction in a first area and a second area, but the first line patterns extend along a second direction in a boundary area. Second line patterns extend along a third direction in the first area and the second area, but the second line patterns extend along a fourth direction in the boundary area, so that minimum distances between overlapping areas of the first line patterns and the second line patterns in the boundary area are larger than minimum distances between overlapping areas of the first line patterns and the second line patterns in the first area and the second area. A trimming process is performed to shade the first line patterns and the second line patterns in the boundary area and the second area.
    Type: Application
    Filed: November 1, 2018
    Publication date: April 9, 2020
    Inventors: Chia-Hung Wang, En-Chiuan Liou, Chien-Hao Chen, Sho-Shen Lee, Yi-Ting Chen, Jhao-Hao Lee
  • Publication number: 20200091419
    Abstract: A conductive via layer is deposited on a bottom electrode, then patterned and trimmed to form a sub 20 nm conductive via on the bottom electrode. The conductive via is encapsulated with a first dielectric layer, which is planarized to expose a top surface of the conductive via. A MTJ stack is deposited on the encapsulated conductive via wherein the MTJ stack comprises at least a pinned layer, a barrier layer, and a free layer. A top electrode layer is deposited on the MTJ stack and patterned and trimmed to form a sub 30 nm hard mask. The MTJ stack is etched using the hard mask to form an MTJ device and over etched into the encapsulation layer but not into the bottom electrode wherein metal re-deposition material is formed on sidewalls of the encapsulation layer underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.
    Type: Application
    Filed: September 18, 2018
    Publication date: March 19, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20200066972
    Abstract: A method for etching a magnetic tunneling junction (MTJ) structure is described. A MTJ stack is deposited on a bottom electrode wherein the MTJ stack comprises at least a pinned layer, a barrier layer on the pinned layer, and a free layer on the barrier layer, A top electrode layer is deposited on the MTJ stack. A hard mask is deposited on the top electrode layer. The top electrode layer and hard mask are etched. Thereafter, the MTJ stack not covered by the hard mask is etched, stopping at or within the pinned layer. Thereafter, an encapsulation layer is deposited over the partially etched MTJ stack and etched away on horizontal surfaces leaving a self-aligned hard mask on sidewalls of the partially etched MTJ stack. Finally, the remaining MTJ stack not covered by hard mask and self-aligned hard mask is etched to complete the MTJ structure.
    Type: Application
    Filed: August 27, 2018
    Publication date: February 27, 2020
    Inventors: Yi Yang, Dongna Shen, Vignesh Sundar, Yu-Jen Wang
  • Publication number: 20200066973
    Abstract: A stack of connecting metal vias is formed on a bottom electrode by repeating steps of depositing a conductive via layer, patterning and trimming the conductive via layer to form a sub 30 nm conductive via, encapsulating the conductive via with a dielectric layer, and exposing a top surface of the conductive via. A MTJ stack is deposited on the encapsulated via stack. A top electrode layer is deposited on the MTJ stack and patterned and trimmed to form a sub 60 nm hard mask. The MTJ stack is etched using the hard mask to form an MTJ device and over etched into the encapsulation layers but not into the bottom electrode wherein metal re-deposition material is formed on sidewalls of the encapsulation layers underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.
    Type: Application
    Filed: August 27, 2018
    Publication date: February 27, 2020
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20200052196
    Abstract: An etch process flow for forming magnetic tunnel junction (MTJ) cells with enhanced throughput that also increases the magnetoresistive ratio and decreases critical dimension (CD) variation is disclosed. A photoresist pattern is formed on a dielectric antireflective coating (DARC), which contacts a top surface of a hard mask (HM) that is an uppermost MTJ layer. After a first ion beam etch (IBE) or reactive ion etch (RIE) transfers the pattern through the DARC, a second etch is used to transfer the pattern through the HM. The second etch includes an oxidant to passivate the pattern sidewalls and completely removes the photoresist layer because of one or both of a thicker DARC and thicker HM than in conventional processing. Accordingly, an oxygen etch typically used to remove the photoresist after the HM etch is avoided and thereby provides improved MTJ performance, especially for CDs<60 nm.
    Type: Application
    Filed: August 7, 2018
    Publication date: February 13, 2020
    Inventors: Dongna Shen, Yi Yang, Yu-Jen Wang
  • Patent number: 10522751
    Abstract: A MTJ stack is deposited on a bottom electrode. A metal hard mask is deposited on the MTJ stack and a dielectric mask is deposited on the metal hard mask. A photoresist pattern is formed on the dielectric mask, having a critical dimension of more than about 65 nm. The dielectric and metal hard masks are etched wherein the photoresist pattern is removed. The dielectric and metal hard masks are trimmed to reduce their critical dimension to 10-60 nm and to reduce sidewall surface roughness. The dielectric and metal hard masks and the MTJ stack are etched wherein the dielectric mask is removed and a MTJ device is formed having a small critical dimension of 10-60 nm, and having further reduced sidewall surface roughness.
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: December 31, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Dongna Shen, Yi Yang, Jesmin Haq, Yu-Jen Wang
  • Patent number: 10522741
    Abstract: A method for fabricating a magnetic tunneling junction (MTJ) structure is described. A first dielectric layer is deposited on a bottom electrode and partially etched through to form a first via opening having straight sidewalls, then etched all the way through to the bottom electrode to form a second via opening having tapered sidewalls. A metal layer is deposited in the second via opening and planarized to the level of the first dielectric layer. The remaining first dielectric layer is removed leaving an electrode plug on the bottom electrode. MTJ stacks are deposited on the electrode plug and on the bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and polished to expose a top surface of the MTJ stack on the electrode plug. A top electrode layer is deposited to complete the MTJ structure.
    Type: Grant
    Filed: June 14, 2018
    Date of Patent: December 31, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Patent number: 10522753
    Abstract: A via connection is provided through a dielectric layer to a bottom electrode. A MTJ stack is deposited on the dielectric layer and via connection. A top electrode is deposited on the MTJ stack. A selective hard mask and then a dielectric hard mask are deposited on the top electrode. The dielectric and selective hard masks are patterned and etched. The dielectric and selective hard masks and the top electrode are etched wherein the dielectric hard mask is removed. The top electrode is trimmed using IBE at an angle of 70 to 90 degrees. The selective hard mask, top electrode, and MTJ stack are etched to form a MTJ device wherein over etching into the dielectric layer surrounding the via connection is performed and re-deposition material is formed on sidewalls of the dielectric layer underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.
    Type: Grant
    Filed: July 26, 2019
    Date of Patent: December 31, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Patent number: 10516102
    Abstract: A MTJ stack is deposited on a bottom electrode. A top electrode layer and hard mask are deposited on the MTJ stack. The top electrode layer not covered by the hard mask is etched. Thereafter, a first spacer layer is deposited over the patterned top electrode layer and the hard mask. The first spacer layer is etched away on horizontal surfaces leaving first spacers on sidewalls of the patterned top electrode layer. The free layer not covered by the hard mask and first spacers is etched. Thereafter, the steps of depositing a subsequent spacer layer over patterned previous layers, etching away the subsequent spacer layer on horizontal surfaces leaving subsequent spacers on sidewalls of the patterned previous layers, and thereafter etching a next layer not covered by the hard mask and subsequent spacers are repeated until all layers of the MTJ stack have been etched to complete the MTJ structure.
    Type: Grant
    Filed: October 16, 2018
    Date of Patent: December 24, 2019
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20190386201
    Abstract: A method for fabricating a magnetic tunneling junction (MTJ) structure is described. A first dielectric layer is deposited on a bottom electrode and partially etched through to form a first via opening having straight sidewalls, then etched all the way through to the bottom electrode to form a second via opening having tapered sidewalls. A metal layer is deposited in the second via opening and planarized to the level of the first dielectric layer. The remaining first dielectric layer is removed leaving an electrode plug on the bottom electrode. MTJ stacks are deposited on the electrode plug and on the bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and polished to expose a top surface of the MTJ stack on the electrode plug. A top electrode layer is deposited to complete the MTJ structure.
    Type: Application
    Filed: June 14, 2018
    Publication date: December 19, 2019
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20190386211
    Abstract: A first conductive layer is patterned and trimmed to form a sub 30 nm conductive via on a first bottom electrode. The conductive via is encapsulated with a first dielectric layer and planarized to expose a top surface of the conductive via. A second conductive layer is deposited over the first dielectric layer and the conductive via. The second conductive layer is patterned to form a sub 60 nm second conductive layer wherein the conductive via and second conductive layer together form a T-shaped second bottom electrode. MTJ stacks are deposited on the T-shaped second bottom electrode and on the first bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and planarized to expose a top surface of the MTJ stack on the T-shaped second bottom electrode. A top electrode contacts the MTJ stack on the T-shaped second bottom electrode plug.
    Type: Application
    Filed: June 26, 2019
    Publication date: December 19, 2019
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Publication number: 20190363248
    Abstract: A MTJ stack is deposited on a bottom electrode. A metal hard mask is deposited on the MTJ stack and a dielectric mask is deposited on the metal hard mask. A photoresist pattern is formed on the dielectric mask, having a critical dimension of more than about 65 nm. The dielectric and metal hard masks are etched wherein the photoresist pattern is removed. The dielectric and metal hard masks are trimmed to reduce their critical dimension to 10-60 nm and to reduce sidewall surface roughness. The dielectric and metal hard masks and the MTJ stack are etched wherein the dielectric mask is removed and a MTJ device is formed having a small critical dimension of 10-60 nm, and having further reduced sidewall surface roughness.
    Type: Application
    Filed: May 22, 2018
    Publication date: November 28, 2019
    Inventors: Dongna Shen, Yi Yang, Jesmin Haq, Yu-Jen Wang
  • Publication number: 20190363249
    Abstract: A magnetic tunneling junction (MTJ) structure comprises a pinned layer on a bottom electrode. a barrier layer on the pinned layer, wherein a second metal re-deposition layer is on sidewalls of the barrier layer and the pinned layer, a free layer on the barrier layer wherein the free layer has a first width smaller than a second width of the pinned layer, a top electrode on the free layer having a same first width as the free layer wherein a first metal re-deposition layer is on sidewalls of the free layer and top electrode, and dielectric spacers on sidewalls of the free layer and top electrode covering the first metal re-deposition layer wherein the free layer and the top electrode together with the dielectric spacers have a same the second width as the pinned layer wherein the dielectric spacers prevent shorting between the first and second metal re-deposition layers.
    Type: Application
    Filed: May 22, 2018
    Publication date: November 28, 2019
    Inventors: Yi Yang, Dongna Shen, Yu-Jen Wang
  • Patent number: D879754
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: March 31, 2020
    Assignee: HTC CORPORATION
    Inventors: Chin-Wei Chou, Yi-Shen Wang, Chien-Hsin Huang, Meng-Sheng Chiang