Patents by Inventor Eric Chih-Fang Liu

Eric Chih-Fang 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).

  • Publication number: 20230352343
    Abstract: A process includes forming, over a dielectric layer, a hardmask stack including a first layer below a second layer below a third layer below a fourth layer. The first and third layers include a different hardmask material from the second and fourth layers. A trench pattern including sidewall spacer structures is formed over the hardmask stack. The fourth layer is etched in a first region. The fourth and third layers are etched in a second region. The fourth and third layers are etched in a third region. The fourth layer is etched in a fourth region. The second and first layers are etched in the second and third regions. The third layer is etched in the first and fourth regions. In the dielectric layer, trenches are formed in the first and fourth regions, and via openings, deeper than the trenches, are formed in the second and third regions.
    Type: Application
    Filed: April 27, 2023
    Publication date: November 2, 2023
    Applicant: Tokyo Electron Limited
    Inventors: Jeffrey SMITH, David POWER, Eric Chih-Fang LIU, Anton J. DEVILLIERS, Kandabara TAPILY, Jodi GRZESKOWIAK, David CONKLIN, Michael MURPHY
  • Publication number: 20230343554
    Abstract: The present disclosure provides various embodiments of plasma processing systems, plasma etch process steps and methods for etching features (e.g., contact holes, vias, trenches, etc.) within one or more material layers formed on a substrate, where such material layers include but are not limited to, a metal hard mask layer formed above a dielectric layer. The embodiments disclosed herein reduce or eliminate problems, such as undercutting of the metal hard mask layer and/or recess into the underlying dielectric layer, that occur during conventional continuous wave plasma etch processes by using a pulsed plasma to etch the features within the metal hard mask layer. A radio frequency (RF) modulated pulsed plasma scheme is disclosed herein to improve anisotropic etching of the features within the metal hard mask layer.
    Type: Application
    Filed: April 20, 2022
    Publication date: October 26, 2023
    Inventors: Ya-Ming Chen, Eric Chih-Fang Liu, Shihsheng Chang, Emilia Hirsch, Na Young Bae, Angelique Raley
  • Publication number: 20230343592
    Abstract: A method of fabricating an amorphous carbon layer (ACL) mask includes forming an ACL on an underlying layer. The ACL includes a soft ACL portion that has a first hardness and a hard ACL portion that has a second hardness. The soft ACL portion underlies the hard ACL portion. The second hardness is greater than the first hardness. The method further includes forming a patterned layer over the ACL and forming an ACL mask by etching through both the soft ACL portion and the hard ACL portion of the ACL to expose the underlying layer using the patterned layer as an etch mask. Forming the ACL may include depositing one or both of the soft ACL portion and the hard ACL portion. Processing conditions may also be varied while forming the ACL to create a hardness gradient that transitions from softer to harder.
    Type: Application
    Filed: April 21, 2022
    Publication date: October 26, 2023
    Inventors: Shihsheng Chang, Andrew Metz, Yun Han, Ya-Ming Chen, Kai-Hung Yu, Eric Chih-Fang Liu
  • Publication number: 20230343598
    Abstract: Various embodiments of stacked structures, process steps and methods are provided herein for etching high aspect ratio features (e.g., contact holes, vias, trenches, etc.) within a stacked structure comprising a hard mask layer, which is formed above and in contact with one or more underlying layers. At least one etch stop layer (ESL) is provided within the hard mask layer to divide the hard mask layer into two or more distinct portions. When the stacked structure is subsequently etched to form high aspect ratio features within the hard mask layer, such as contact holes or vias that extend through the hard mask layer, the ESL(s) included within the hard mask layer improve etch rate and critical dimension (CD) uniformity of the features etched within the hard mask layer.
    Type: Application
    Filed: April 22, 2022
    Publication date: October 26, 2023
    Inventors: Shihsheng Chang, Andrew Metz, Yun Han, Minjoon Park, Kai-Hung Yu, Eric Chih-Fang Liu
  • Patent number: 11756790
    Abstract: A method is described for patterning a dielectric layer disposed over a semiconductor substrate layer. The patterning process includes forming a patterned hard mask layer over the dielectric layer, the patterned hard mask layer exposing a portion of a major surface of the dielectric layer. A portion of the dielectric layer is removed by a cyclic etch process, where performing one cycle of the cyclic etch process comprises forming a capping layer selectively over the patterned hard mask layer and performing a timed etch process that removes material from the dielectric layer. In another method, the deposition over the hard mask and the removal of the portion of the dielectric layer are performed concurrently.
    Type: Grant
    Filed: March 9, 2021
    Date of Patent: September 12, 2023
    Assignee: Tokyo Electron Limited
    Inventors: Yen-Tien Lu, Xinghua Sun, Shihsheng Chang, Eric Chih-Fang Liu, Angelique Raley, Katie Lutker-Lee
  • Publication number: 20230154752
    Abstract: Methods are provided herein for forming spacers on a patterned substrate. A self-aligned multiple patterning (SAMP) process is utilized for patterning structures, spacers formed adjacent mandrels, on a substrate. In one embodiment, a novel approach of etching titanium oxide (TiO2) spacers is provided. Highly anisotropic etching of the spacer along with a selective top deposition is provided. In one embodiment, an inductively coupled plasma (ICP) etch tool is utilized. The etching process may be achieved as a one-step etching process. More particularly, a protective layer may be selectively formed on the top of the spacer to protect the mandrel as well as minimize the difference of the etching rates of the spacer top and the spacer bottom. In one embodiment, the techniques may be utilized to etch TiO2 spacers formed along amorphous silicon mandrels using an ICP etch tool utilizing a one-step etch process.
    Type: Application
    Filed: November 12, 2021
    Publication date: May 18, 2023
    Inventors: Ya-Ming Chen, Katie Lutker-Lee, Eric Chih-Fang Liu, Angelique Raley, Stephanie Oyola-Reynoso, Shihsheng Chang
  • Patent number: 11651965
    Abstract: Embodiments are described herein that apply capping layers to cores prior to spacer formation in self-aligned multiple patterning (SAMP) processes to achieve vertical spacer profiles. For one embodiment, a plasma process is used to deposit a capping layer on cores, and this capping layer causes resulting core profiles to have protective caps. These protective caps formed with the additional capping layer help to reduce or minimize material loss and corner loss of the core material during spacer deposition and spacer etch processes. This reduction in core material loss improves the resulting spacer profile so that a more vertical profile is achieved. For one embodiment, an angle of 80-90 degrees is achieved for vertical sidewalls of the spacers adjacent core sites with respect to the horizontal surface of the underlying layer, such as a hard mask layer formed on a substrate for a microelectronic workpiece.
    Type: Grant
    Filed: August 7, 2020
    Date of Patent: May 16, 2023
    Assignee: Tokyo Electron Limited
    Inventors: Eric Chih-Fang Liu, Akiteru Ko
  • Patent number: 11557479
    Abstract: Methods process microelectronic workpieces with inverse extreme ultraviolet (EUV) patterning processes. In part, the inverse patterning techniques are applied to reduce or eliminate defects experienced with conventional EUV patterning processes. The inverse patterning techniques include additional process steps as compared to the conventional EUV patterning processes, such as an overcoat process, an etch back or planarization process, and a pattern removal process. In addition, further example embodiments combine inverse patterning techniques with line smoothing treatments to reduce pattern roughness and achieve a target level of line roughness. By using this additional technique, line pattern roughness can be significantly improved in addition to reducing or eliminating microbridge and/or other defects.
    Type: Grant
    Filed: March 19, 2020
    Date of Patent: January 17, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Eric Chih-Fang Liu, Akiteru Ko, Subhadeep Kal, Toshiharu Wada
  • Publication number: 20220359718
    Abstract: A method including providing a substrate including metal gate stacks and source/drain contact regions in alternating arrangement along a surface of the substrate, each of the source/drain contact regions being recessed within a respective opening between adjacent metal gate stacks such that source/drain contact regions provide a bottom of the opening and adjacent metal gate stacks provide sidewalls, and a dielectric covering the substrate such that the dielectric fills each opening. The substrate is exposed to an initial plasma etch process to remove a first portion of the dielectric from each opening down to a first depth, and a sacrificial gate capping layer is formed on the substrate while leaving each of the openings uncovered. The substrate is exposed to another plasma etch process to remove the sacrificial gate capping layer while removing a second portion of the dielectric from each opening down to a second depth.
    Type: Application
    Filed: April 15, 2022
    Publication date: November 10, 2022
    Applicant: Tokyo Electron Limited
    Inventors: Yun HAN, Eric Chih-Fang LIU, Kai-Hung YU, Shihsheng CHANG, Alok RANJAN
  • Publication number: 20220319838
    Abstract: A substrate is provided with a patterned layer, such as, a photo resist layer which may exhibit line roughness. The patterned layer may be an EUV photo resist layer utilized in a self-aligned multi-patterning process. A tone inversion process having a tone inversion layer is utilized along with a surface treatment of a sidewall of the tone inversion layer so as to improve line roughness characteristics of the process. More specifically, a tone inversion layer may be patterned and then sidewalls of the tone inversion layer may be treated. A fill material may then be deposited upon the substrate including adjacent the sidewalls of the tone inversion layer. When the tone inversion layer is removed, the roughness of the fill material will be reduced due to the use of the sidewall treatment.
    Type: Application
    Filed: April 1, 2021
    Publication date: October 6, 2022
    Inventors: Eric Chih-Fang Liu, Angelique Raley, Kai-Hung Yu
  • Publication number: 20220301930
    Abstract: A method for filling recessed features with a low-resistivity metal. The method includes providing a patterned substrate containing a recessed feature formed in a first layer and a second layer that is exposed in the recessed feature, forming a nucleation enhancement layer on a sidewall of the first layer in the recessed feature and depositing a metal layer in the recessed feature by vapor phase deposition, where the metal layer is deposited on the second layer and on the nucleation enhancement layer. An initial metal layer may be selectively formed on the second layer in the recessed feature before forming the nucleation enhancement layer.
    Type: Application
    Filed: March 7, 2022
    Publication date: September 22, 2022
    Inventors: Kai-Hung Yu, Shihsheng Chang, Ying Trickett, Eric Chih-Fang Liu, Yun Han, Henan Zhang, Cory Wajda, Robert D. Clark, Gerrit J. Leusink, Gyanaranjan Pattanaik, Hiroaki Niimi
  • Publication number: 20220293419
    Abstract: A method is described for patterning a dielectric layer disposed over a semiconductor substrate layer. The patterning process includes forming a patterned hard mask layer over the dielectric layer, the patterned hard mask layer exposing a portion of a major surface of the dielectric layer. A portion of the dielectric layer is removed by a cyclic etch process, where performing one cycle of the cyclic etch process comprises forming a capping layer selectively over the patterned hard mask layer and performing a timed etch process that removes material from the dielectric layer. In another method, the deposition over the hard mask and the removal of the portion of the dielectric layer are performed concurrently.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 15, 2022
    Inventors: Yen-Tien Lu, Xinghua Sun, Shihsheng Chang, Eric Chih-Fang Liu, Angelique Raley, Katie Lutker-Lee
  • Patent number: 11424123
    Abstract: In certain embodiments, a method of forming a semiconductor device includes forming a patterned resist layer over a hard mask layer using an extreme ultraviolet (EUV) lithography process. The hard mask layer is disposed over a substrate. The method includes patterning the hard mask layer using the patterned resist layer as an etch mask. The method includes smoothing the hard mask layer by forming, using a first atomic layer etch step, a first layer by converting a first portion of the hard mask layer, and by removing, using a second atomic layer etch step, the first layer.
    Type: Grant
    Filed: April 17, 2020
    Date of Patent: August 23, 2022
    Assignee: Tokyo Electron Limited
    Inventors: Eric Chih-Fang Liu, Akiteru Ko, Angelique Raley, Henan Zhang, Shan Hu, Subhadeep Kal
  • Patent number: 11417526
    Abstract: A method of forming a device includes depositing a first etch mask layer over a mandrel formed using a lithography process. The method includes depositing a second etch mask layer over the first etch mask layer. The method includes, using a first anisotropic etching process, etching the first etch mask layer and the second etch mask layer to form an etch mask including the first etch mask layer and the second etch mask layer. The method includes removing the mandrel to expose an underlying surface of the layer to be patterned. The method includes, using the etch mask, forming a feature by performing a second anisotropic etching process to pattern the layer to be patterned, where during the first anisotropic etching process, the first etch mask layer etches at a first rate and the second etch mask layer etches at a second rate, and where the first rate is different from the second rate.
    Type: Grant
    Filed: February 3, 2020
    Date of Patent: August 16, 2022
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: David L. O'Meara, Eric Chih-Fang Liu, Jodi Grzeskowiak, Anton deVilliers, Akiteru Ko, Anthony Dip
  • Publication number: 20220244636
    Abstract: An additional non-photoresist layer may be formed on patterned photoresist layers. The additional layer may be preferentially formed on the tops of the photoresist layer versus the sidewalls of the photoresist layer. In addition, the additional layer may be preferential formed on the tops of the photoresist layer versus exposed surfaces of layers underlying the photoresist layer. In this manner, the patterned structures formed by the photoresist layer are less likely to have line opens due to photoresist height variability or the relative thinness of the photoresist height used. Further, the formation of the additional layer may be through a cyclic deposition/trim process. The trim step of the cyclic process may also serve as a descum step that helps reduce line bridging and scumming. In one embodiment, the additional non-photoresist layer may be an organic polymer layer.
    Type: Application
    Filed: April 20, 2022
    Publication date: August 4, 2022
    Inventors: Angélique D. Raley, Eric Chih-Fang Liu, Nihar Mohanty
  • Patent number: 11333968
    Abstract: An additional non-photoresist layer may be formed on patterned photoresist layers. The additional layer may be preferentially formed on the tops of the photoresist layer versus the sidewalls of the photoresist layer. In addition, the additional layer may be preferential formed on the tops of the photoresist layer versus exposed surfaces of layers underlying the photoresist layer. In this manner, the patterned structures formed by the photoresist layer are less likely to have line opens due to photoresist height variability or the relative thinness of the photoresist height used. Further, the formation of the additional layer may be through a cyclic deposition/trim process. The trim step of the cyclic process may also serve as a descum step that helps reduce line bridging and scumming. In one embodiment, the additional non-photoresist layer may be an organic polymer layer.
    Type: Grant
    Filed: February 22, 2018
    Date of Patent: May 17, 2022
    Assignee: Tokyo Electron Limited
    Inventors: Angelique D. Raley, Eric Chih-Fang Liu, Nihar Mohanty
  • Publication number: 20210296125
    Abstract: Methods process microelectronic workpieces with inverse extreme ultraviolet (EUV) patterning processes. In part, the inverse patterning techniques are applied to reduce or eliminate defects experienced with conventional EUV patterning processes. The inverse patterning techniques include additional process steps as compared to the conventional EUV patterning processes, such as an overcoat process, an etch back or planarization process, and a pattern removal process. In addition, further example embodiments combine inverse patterning techniques with line smoothing treatments to reduce pattern roughness and achieve a target level of line roughness. By using this additional technique, line pattern roughness can be significantly improved in addition to reducing or eliminating microbridge and/or other defects.
    Type: Application
    Filed: March 19, 2020
    Publication date: September 23, 2021
    Inventors: Eric Chih-Fang Liu, Akiteru Ko, Subhadeep Kal, Toshiharu Wada
  • Patent number: 11121027
    Abstract: A method for the via etching steps of a substrate manufacturing process flow is provided. The substrate processing techniques described provide for etching vias by providing a protection layer on the via sidewall during at least portions of the via etching process. In one embodiment, an atomic layer deposition (ALD) layer is formed on the via sidewalls to protect the dielectric layers through which the via is formed. The ALD layer may lessen bowing effects in low k dielectric layers which may result from etching barrier low k (blok) layers or from other process steps. After via formation, the ALD layer may be removed. The techniques are particularly suited for forming skip vias and other high aspect ratio vias formed in low k and ultra-low k dielectric layers.
    Type: Grant
    Filed: December 7, 2018
    Date of Patent: September 14, 2021
    Assignee: Tokyo Electron Limited
    Inventors: Yen-Tien Lu, Xinghua Sun, Eric Chih-Fang Liu, Andrew W. Metz
  • Publication number: 20210265164
    Abstract: In certain embodiments, a method of forming a semiconductor device includes forming a patterned resist layer over a hard mask layer using an extreme ultraviolet (EUV) lithography process. The hard mask layer is disposed over a substrate. The method includes patterning the hard mask layer using the patterned resist layer as an etch mask. The method includes smoothing the hard mask layer by forming, using a first atomic layer etch step, a first layer by converting a first portion of the hard mask layer, and by removing, using a second atomic layer etch step, the first layer.
    Type: Application
    Filed: April 17, 2020
    Publication date: August 26, 2021
    Inventors: Eric Chih-Fang Liu, Akiteru Ko, Angelique Raley, Henan Zhang, Shan Hu, Subhadeep Kal
  • Publication number: 20210242020
    Abstract: A method of forming a device includes depositing a first etch mask layer over a mandrel formed using a lithography process. The method includes depositing a second etch mask layer over the first etch mask layer. The method includes, using a first anisotropic etching process, etching the first etch mask layer and the second etch mask layer to form an etch mask including the first etch mask layer and the second etch mask layer. The method includes removing the mandrel to expose an underlying surface of the layer to be patterned. The method includes, using the etch mask, forming a feature by performing a second anisotropic etching process to pattern the layer to be patterned, where during the first anisotropic etching process, the first etch mask layer etches at a first rate and the second etch mask layer etches at a second rate, and where the first rate is different from the second rate.
    Type: Application
    Filed: February 3, 2020
    Publication date: August 5, 2021
    Inventors: David L. O'Meara, Eric Chih-Fang Liu, Jodi Grzeskowiak, Anton deVilliers, Akiteru Ko, Anthony Dip