Patents by Inventor Shehrin Sayed

Shehrin Sayed 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: 20250111863
    Abstract: The present embodiments relate to a PMR write-head structure where the spin-orbit torque (SOT) material is in contact with the main pole in the write gap (WG). In addition, with the write shield (WS) electrically isolated from the side shield (SS) in the present designs, the current can be confined in the SOT material near the main pole, and the device resistance can remain within a reasonable range. It can be shown, using simulations, that the main pole switching rise time can be improved by 18˜24% using spin-orbit torque from heavy metals like platinum.
    Type: Application
    Filed: September 29, 2023
    Publication date: April 3, 2025
    Inventors: Shehrin Sayed, Haowen Ren, Yue Liu, Wenyu Chen, Yuhui Tang
  • Publication number: 20250095672
    Abstract: The present embodiments relate to a write head design with a patterned hot seed (HS). Particularly, the HS can be patterned as part of a multi-step patterning process that can partially or completely remove portions of the HS at multiple sides to form various designs. For example, the HS can have a two-step cliff design, etching multiple steps around an un-patterned center portion, and a flared angle. The designs of the patterned HS can improve write head performance.
    Type: Application
    Filed: September 18, 2023
    Publication date: March 20, 2025
    Inventors: Haowen Ren, Weihao Xu, Yuxuan Xiao, Shehrin Sayed, Yue Liu, Yan Wu, Yuhui Tang
  • Publication number: 20250078862
    Abstract: The present embodiments can generally provide a magnetic write head structure with optimized gap current distribution to maximize the current-assisted areal density capacity (ADC) gain in hard-disk-drive storage devices. In a first example embodiment, a non-dual-write-shield (nDWS) write head can include a main pole (MP), a trailing shield (TS), and a write gap (WG) disposed between the MP and the TS. The write head can also include a side shield (SS), a leading shield (LS), and a write shield (WS). The write head can include a side gap (SG) between the MP and the SS on both sides of the MP tip, and a leading gap (LG) between the MP and the LS. The write head can also include a coil wrapped around the MP through a PP3 shield that is configured to direct a time-dependent write current to saturate magnetization of the MP.
    Type: Application
    Filed: September 6, 2024
    Publication date: March 6, 2025
    Inventors: Shehrin Sayed, Wenyu Chen, Yue Liu, Kowang Liu, Tetsuya Roppongi, Haowen Ren, Yuhui Tang, Moris Musa Dovek, Wenjie Chen
  • Publication number: 20240349624
    Abstract: A rectifier device, has a Hall layer comprising a layer of a Hall material, and a spin-orbit layer adjacent the Hall layer. The spin-orbit layer has a spin-orbit material having a first surface and a second surface, a ferromagnet adjacent the spin-orbit material, and oxide on the outer surfaces of the spin-orbit layer. A rectifying system has an array of the above rectifying devices having a number, K, of parallel branches, each branch having N devices, branch electrical connections between corresponding devices in each of the parallel branches, and device electrical connection between devices in each parallel branch.
    Type: Application
    Filed: October 28, 2021
    Publication date: October 17, 2024
    Inventors: Eli Yablonovitch, Sayeef Salahuddin, Shehrin Sayed
  • Patent number: 12094497
    Abstract: The present embodiments can generally provide a magnetic write head structure with optimized gap current distribution to maximize the current-assisted areal density capacity (ADC) gain in hard-disk-drive storage devices. In a first example embodiment, a non-dual-write-shield (nDWS) write head can include a main pole (MP), a trailing shield (TS), and a write gap (WG) disposed between the MP and the TS. The write head can also include a side shield (SS), a leading shield (LS), and a write shield (WS). The write head can include a side gap (SG) between the MP and the SS on both sides of the MP tip, and a leading gap (LG) between the MP and the LS. The write head can also include a coil wrapped around the MP through a PP3 shield that is configured to direct a time-dependent write current to saturate magnetization of the MP.
    Type: Grant
    Filed: August 30, 2023
    Date of Patent: September 17, 2024
    Assignee: Headway Technologies, Inc.
    Inventors: Shehrin Sayed, Wenyu Chen, Yue Liu, Kowang Liu, Tetsuya Roppongi, Haowen Ren, Yuhui Tang, Moris Musa Dovek, Wenjie Chen
  • Patent number: 11742011
    Abstract: The present disclosure relates to a magnetic memory structure with a voltage-controlled gain-cell configuration, which includes a memory resistive device, a first transistor connected in series with the memory resistive device, and a second transistor. The memory resistive device has a baseline resistance larger than 10 M?, and is eligible to exhibit a ‘1’ state and a ‘0’ state and exhibit a resistance change between the ‘1’ state and the ‘0’ state. The second transistor has a gate connected to a connection node of the first transistor and the memory resistive device. When the memory resistive device exhibits the ‘1’ state, a gate voltage for the second transistor is smaller than a threshold voltage of the second transistor, and when the memory resistive device exhibits the ‘0’ state, the gate voltage for the second transistor is larger than the threshold voltage of the second transistor.
    Type: Grant
    Filed: August 11, 2021
    Date of Patent: August 29, 2023
    Assignee: The Regents of the University of California
    Inventors: Sayeef Salahuddin, Shehrin Sayed
  • Publication number: 20230045804
    Abstract: The present disclosure relates to a magnetic memory structure with a voltage-controlled gain-cell configuration, which includes a memory resistive device, a first transistor connected in series with the memory resistive device, and a second transistor. The memory resistive device has a baseline resistance larger than 10 M?, and is eligible to exhibit a ‘1’ state and a ‘0’ state and exhibit a resistance change between the ‘1’ state and the ‘0’ state. The second transistor has a gate connected to a connection node of the first transistor and the memory resistive device. When the memory resistive device exhibits the ‘1’ state, a gate voltage for the second transistor is smaller than a threshold voltage of the second transistor, and when the memory resistive device exhibits the ‘0’ state, the gate voltage for the second transistor is larger than the threshold voltage of the second transistor.
    Type: Application
    Filed: August 11, 2021
    Publication date: February 16, 2023
    Inventors: Sayeef Salahuddin, Shehrin Sayed
  • Patent number: 11417834
    Abstract: A switching device is disclosed. The switching device includes a spin-orbit coupling (SOC) layer, a pure spin conductor (PSC) layer disposed atop the SOC layer, a ferromagnetic (FM) layer disposed atop the PSC layer, and a normal metal (NM) layer sandwiched between the PSC layer and the FM layer. The PSC layer is a ferromagnetic insulator (FMI) is configured to funnel spins from the SOC layer onto the NM layer and to further provide a charge insulation so as to substantially eliminate current shunting from the SOC layer while allowing spins to pass through. The NM layer is configured to funnel spins from the PSC layer into the FM layer.
    Type: Grant
    Filed: December 23, 2019
    Date of Patent: August 16, 2022
    Assignee: Purdue Research Foundation
    Inventors: Shehrin Sayed, Vinh Quang Diep, Kerem Y Camsari, Supriyo Datta
  • Patent number: 10964468
    Abstract: A magnetic memory structure employs electric-field controlled interlayer exchange coupling between a free magnetic layer and a fixed magnetic layer to switch a magnetization direction. The magnetic layers are separated by a spacer layer disposed between two oxide layers. The spacer layer exhibits a large IEC while the oxide layers provide tunnel barriers, forming a quantum-well between the magnetic layers with discrete energy states above the equilibrium Fermi level. When an electric field is applied across the structure, the tunnel barriers become transparent at discrete energy states via a resonant tunneling phenomenon. The wave functions of the two magnets then can interact and interfere to provide a sizable IEC. IEC can control the magnetization direction of the free magnetic layer relative to the magnetization direction of the fixed magnetic layer depending on the sign of the IEC, induced by a magnitude of the applied electric field above a threshold value.
    Type: Grant
    Filed: July 12, 2019
    Date of Patent: March 30, 2021
    Assignee: The Regents of the University of California
    Inventors: Sayeef Salahuddin, Shehrin Sayed
  • Publication number: 20210012940
    Abstract: A magnetic memory structure employs electric-field controlled interlayer exchange coupling between a free magnetic layer and a fixed magnetic layer to switch a magnetization direction. The magnetic layers are separated by a spacer layer disposed between two oxide layers. The spacer layer exhibits a large IEC while the oxide layers provide tunnel barriers, forming a quantum-well between the magnetic layers with discrete energy states above the equilibrium Fermi level. When an electric field is applied across the structure, the tunnel barriers become transparent at discrete energy states via a resonant tunneling phenomenon. The wave functions of the two magnets then can interact and interfere to provide a sizable IEC. IEC can control the magnetization direction of the free magnetic layer relative to the magnetization direction of the fixed magnetic layer depending on the sign of the IEC, induced by a magnitude of the applied electric field above a threshold value.
    Type: Application
    Filed: July 12, 2019
    Publication date: January 14, 2021
    Inventors: Sayeef Salahuddin, Shehrin Sayed
  • Publication number: 20200136024
    Abstract: A switching device is disclosed. The switching device includes a spin-orbit coupling (SOC) layer, a pure spin conductor (PSC) layer disposed atop the SOC layer, a ferromagnetic (FM) layer disposed atop the PSC layer, and a normal metal (NM) layer sandwiched between the PSC layer and the FM layer. The PSC layer is a ferromagnetic insulator (FMI) is configured to funnel spins from the SOC layer onto the NM layer and to further provide a charge insulation so as to substantially eliminate current shunting from the SOC layer while allowing spins to pass through. The NM layer is configured to funnel spins from the PSC layer into the FM layer.
    Type: Application
    Filed: December 23, 2019
    Publication date: April 30, 2020
    Applicant: Purdue Research Foundation
    Inventors: Shehrin Sayed, Vinh Quang Diep, Kerem Y. Camsari, Supriyo Datta
  • Patent number: 10516098
    Abstract: A switching device is disclosed. The switching device includes a spin-orbit coupling (SOC) layer, a pure spin conductor (PSC) layer disposed atop the SOC layer, a ferromagnetic (FM) layer disposed atop the PSC layer, and a normal metal (NM) layer sandwiched between the PSC layer and the FM layer. The PSC layer is a ferromagnetic insulator (FMI) is configured to funnel spins from the SOC layer onto the NM layer and to further provide a charge insulation so as to substantially eliminate current shunting from the SOC layer while allowing spins to pass through. The NM layer is configured to funnel spins from the PSC layer into the FM layer.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: December 24, 2019
    Assignee: Purdue Research Foundation
    Inventors: Shehrin Sayed, Vinh Quang Diep, Kerem Y Camsari, Supriyo Datta
  • Patent number: 10497416
    Abstract: A spintronic memory device having a spin momentum-locking (SML) channel, a nanomagnet structure (NMS) disposed on the SML, and a plurality of normal metal electrodes disposed on the SML. The magnetization orientation of the NMS is controlled by current injection into the SML through normal metal electrode. The magnetization orientation of the NMS is determined by measuring voltages across the NMS and the SML while flowing charge current through the SML via the normal metal electrodes.
    Type: Grant
    Filed: February 13, 2018
    Date of Patent: December 3, 2019
    Assignee: Purdue Research Foundation
    Inventors: Shehrin Sayed, Supriyo Datta, Esteban E. Marinero-Caceres
  • Publication number: 20180233188
    Abstract: A spintronic memory device having a spin momentum-locking (SML) channel, a nanomagnet structure (NMS) disposed on the SML, and a plurality of normal metal electrodes disposed on the SML. The magnetization orientation of the NMS is controlled by current injection into the SML through normal metal electrode. The magnetization orientation of the NMS is determined by measuring voltages across the NMS and the SML while flowing charge current through the SML via the normal metal electrodes.
    Type: Application
    Filed: February 13, 2018
    Publication date: August 16, 2018
    Applicant: Purdue Research Foundation
    Inventors: Shehrin Sayed, Supriyo Datta, Esteban E. Marinero-Caceras
  • Publication number: 20180182954
    Abstract: A switching device is disclosed. The switching device includes a spin-orbit coupling (SOC) layer, a pure spin conductor (PSC) layer disposed atop the SOC layer, a ferromagnetic (FM) layer disposed atop the PSC layer, and a normal metal (NM) layer sandwiched between the PSC layer and the FM layer. The PSC layer is a ferromagnetic insulator (FMI) is configured to funnel spins from the SOC layer onto the NM layer and to further provide a charge insulation so as to substantially eliminate current shunting from the SOC layer while allowing spins to pass through. The NM layer is configured to funnel spins from the PSC layer into the FM layer.
    Type: Application
    Filed: December 22, 2017
    Publication date: June 28, 2018
    Applicant: Purdue Research Foundation
    Inventors: Shehrin Sayed, Vinh Quang Diep, Kerem Y. Camsari, Supriyo Datta