Patents by Inventor Tongtong ZHU
Tongtong ZHU 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: 20240014348Abstract: A method of manufacturing an LED device comprises the steps of: forming a second LED structure over a first LED structure, in which at least one of the first or second LED structures is positioned over a porous region of III-nitride material. An LED device comprises a second LED structure positioned over a first LED structure, in which at least one of the first or second LED structures is positioned over a porous region of III-nitride material. An array of LEDs and a three-colour LED device are also provided.Type: ApplicationFiled: August 4, 2021Publication date: January 11, 2024Inventors: Yingjun LIU, Tongtong ZHU, Muhammad ALI
-
Publication number: 20230378237Abstract: A method of manufacturing an LED device comprises the steps of: providing a template comprising a first porous region of III-nitride material; forming a first LED structure on the template above the first porous region; and forming a second LED structure on the template, in which the second LED structure is not positioned above the first porous region. An LED device comprises a first LED structure, over a first porous region of III-nitride material; and a second LED structure which is not positioned over the first porous region. A three colour LED device is also provided.Type: ApplicationFiled: August 4, 2021Publication date: November 23, 2023Inventors: Yingjun LIU, Tongtong ZHU, Muhammad ALI
-
Publication number: 20230361252Abstract: An LED device comprises a plurality of light-emitting diodes (LEDs), and an optical filter arranged to filter light emitted by the plurality of LEDs. The optical filter comprises a first region arranged to filter light emitted from a first portion of the plurality of LEDs, in which the first region of the optical filter comprises a Distributed Bragg Reflector (DBR) configured to prevent transmission of light of a predetermined wavelength ?1. The LED device may comprise a colour-conversion material positioned between the first portion of the LEDs and the DBR, the colour-conversion material being configured to emit light at one or more wavelengths different from the emission wavelength ?1 of the first portion of LEDs. An optical filter and a method of manufacture are also provided.Type: ApplicationFiled: September 10, 2021Publication date: November 9, 2023Inventors: Tongtong ZHU, Yingjun LIU, Muhammad ALI
-
Publication number: 20230290806Abstract: A method of manufacturing an LED device comprises the steps of: forming an n-doped connecting layer of III-nitride material over a porous region of III-nitride material; forming a first electrically-insulating mask layer on the n-doped connecting layer; removing a portion of the first mask layer to expose a first exposed region of the n-doped connecting layer; forming a first LED structure, which is configured to emit light at a first emission wavelength, on the first exposed region of the n-doped connecting layer; forming a second electrically-insulating mask layer over the first LED structure and the n-doped connecting layer; removing a portion of the second mask layer to expose a second exposed region of the n-doped connecting layer; and forming a second LED structure, which is configured to emit light at a second emission wavelength different from the first emission wavelength, on the second exposed region of the n-doped connecting layer.Type: ApplicationFiled: August 4, 2021Publication date: September 14, 2023Inventors: Tongtong ZHU, Yingjun LIU, Muhammad ALI
-
Publication number: 20230290903Abstract: A light emitting diode (LED) comprises: an n-doped portion; a p-doped portion; and a light emitting region located between the n-doped portion and the p-doped portion. The light emitting region comprises: a light-emitting layer which emits light at a peak wavelength between 400 and 599 nm under electrical bias thereacross; a III-nitride layer located on the light-emitting layer; and a III-nitride barrier layer located on the III-nitride layer. The light emitting diode comprises a porous region of III-nitride material. An LED array and a method of manufacturing an LED with a peak emission wavelength between 400 nm and 599 nm under electrical bias are also provided.Type: ApplicationFiled: August 4, 2021Publication date: September 14, 2023Inventors: Tongtong ZHU, Yingjun LIU, Muhammad ALI
-
Publication number: 20230167576Abstract: A wafer holder for holding a semiconductor wafer during electrochemical porosification with an electrolyte comprises a housing for receiving the semiconductor wafer, an aperture in the housing, through which an upper surface of the semiconductor wafer is exposable to the electrolyte, a seal extending around the aperture, for preventing the ingress of electrolyte into the housing; and an electrical contact for making an electrical connection with the semiconductor wafer. A method of electrochemical porosification of a semiconductor wafer comprises the steps of placing a semiconductor wafer in a wafer holder; immersing the housing in an electrolyte, so that the surface of the semiconductor wafer is exposed to electrolyte through the aperture; and applying a potential difference between the semiconductor wafer and the electrolyte.Type: ApplicationFiled: April 28, 2021Publication date: June 1, 2023Inventors: Tongtong ZHU, Yingjun LIU
-
Patent number: 11651954Abstract: A method for porosifying a Ill-nitride material in a semiconductor structure is provided, the semiconductor structure comprising a sub-surface structure of a first Ill-nitride material, having a charge carrier density greater than 5×1017 cm?3, beneath a surface layer of a second Ill-nitride material, having a charge carrier density of between 1×1014 cm?3 and 1×1017 cm?3. The method comprises the steps of exposing the surface layer to an electrolyte, and applying a potential difference between the first Ill-nitride material and the electrolyte, so that the sub-surface structure is porosified by electrochemical etching, while the surface layer is not porosified. A semiconductor structure and uses thereof are further provided.Type: GrantFiled: September 27, 2017Date of Patent: May 16, 2023Assignee: CAMBRIDGE ENTERPRISE LTDInventors: Tongtong Zhu, Rachel A. Oliver, Yingjun Liu
-
Patent number: 11631782Abstract: A method for etching a semiconductor structure (110) is provided, the semiconductor structure comprising a sub-surface quantum structure (30) of a first III-V semiconductor material,beneath a surface layer (31) of a second III-V semiconductor material having a charge carrier density of less than 5×1017 cm?3. The sub-surface quantum structure may comprise, for example, a quantum well, or a quantum wire, or a quantum dot. The method comprises the steps of exposing the surface layer to an electrolyte (130), and applying a potential difference between the first III-V semiconductor material and the electrolyte, to electrochemically etch the sub-surface quantum structure (30) to form a plurality of nanostructures, while the surface layer (31) is not etched. A semiconductor structure, uses thereof, and devices incorporating such semiconductor structures are further provided.Type: GrantFiled: January 25, 2019Date of Patent: April 18, 2023Assignee: CAMBRIDGE ENTERPRISE LIMITEDInventors: Rachel A. Oliver, Tongtong Zhu, Yingjun Liu, Peter Griffin
-
Publication number: 20230105367Abstract: A method for etching a semiconductor structure (110) is provided, the semiconductor structure comprising a sub-surface quantum structure (30) of a first III-V semiconductor material, beneath a surface layer (31) of a second III-V semiconductor material having a charge carrier density of less than 5 × 1017 cm-3. The sub-surface quantum structure may comprise, for example, a quantum well, or a quantum wire, or a quantum dot. The method comprises the steps of exposing the surface layer to an electrolyte (130), and applying a potential difference between the first III-V semiconductor material and the electrolyte, to electrochemically etch the sub-surface quantum structure (30) to form a plurality of nanostructures, while the surface layer (31) is not etched. A semiconductor structure, uses thereof, and devices incorporating such semiconductor structures are further provided.Type: ApplicationFiled: November 30, 2022Publication date: April 6, 2023Inventors: Rachel A. OLIVER, Tongtong ZHU, Yingjun LIU, Peter GRIFFIN
-
Publication number: 20230096352Abstract: A method for porosifying a III-nitride material in a semiconductor structure is provided, the semiconductor structure comprising a sub-surface structure of a first III-nitride material, having a charge carrier density greater than 5×1017 cm?3, beneath a surface layer of a second III-nitride material, having a charge carrier density of between 1×1014 cm?3 and 1×1017 cm?3. The method comprises the steps of exposing the surface layer to an electrolyte, and applying a potential difference between the first III-nitride material and the electrolyte, so that the sub-surface structure is porosified by electrochemical etching, while the surface layer is not porosified. A semiconductor structure and uses thereof are further provided.Type: ApplicationFiled: November 30, 2022Publication date: March 30, 2023Inventors: Tongtong ZHU, Rachel A. OLIVER, Yingjun LIU
-
Publication number: 20230053144Abstract: A red-light emitting diode (LED) comprises: an n-doped portion; a p-doped portion; and a light emitting region located between the n-doped portion and a p-doped portion. The light emitting region comprises: a light-emitting indium gallium nitride layer which emits light at a peak wavelength between 600 and 750 nm under electrical bias thereacross; a III-nitride layer located on the light-emitting indium gallium nitride layer; and a III-nitride barrier layer located on the III-nitride layer, and the light emitting diode comprises a porous region of III-nitride material. A red mini LED, a red micro-LED, an array of micro-LEDs, and a method of manufacturing a red LED are also provided.Type: ApplicationFiled: January 22, 2021Publication date: February 16, 2023Inventors: Muhammad ALI, Yingjun LIU, Tongtong ZHU
-
Publication number: 20230053213Abstract: A semiconductor structure comprises a layer of a first III-nitride material having a first lattice dimension; a non-porous layer of a second III-nitride material having a second lattice dimension different from the first lattice dimension; and a porous region of III-nitride material disposed between the layer of first III-nitride material and the non-porous layer of the second III-nitride material. An optoelectronic semiconductor device, an LED, and a method of manufacturing a semiconductor structure are also provided.Type: ApplicationFiled: January 22, 2021Publication date: February 16, 2023Inventors: Muhammad ALI, Rachel OLIVER, Tongtong ZHU
-
Publication number: 20230048093Abstract: A method of manufacturing a micro-LED comprises the steps of forming an n-doped connecting layer of III-nitride material over a porous region of III-nitride material, and forming an electrically-insulating mask layer on the n-doped connecting layer. The method comprises the steps of removing a portion of the mask to expose an exposed region of the n-doped connecting layer, and forming an LED structure on the exposed region of the n-doped connecting layer. A method of manufacturing an array of micro-LEDs comprises the step of removing a portion of the mask to expose an array of exposed regions of the n-doped connecting layer, and forming an LED structure on each exposed region of the n-doped connecting layer. A micro-LED and array of micro-LEDs are also provided.Type: ApplicationFiled: January 22, 2021Publication date: February 16, 2023Inventors: Muhammad ALI, Yingjun LIU, Tongtong ZHU
-
Publication number: 20210057601Abstract: A method for etching a semiconductor structure (110) is provided, the semiconductor structure comprising a sub-surface quantum structure (30) of a first III-V semiconductor material,beneath a surface layer (31) of a second III-V semiconductor material having a charge carrier density of less than 5×1017 cm3. The sub-surface quantum structure may comprise, for example, a quantum well, or a quantum wire, or a quantum dot. The method comprises the steps of exposing the surface layer to an electrolyte (130), and applying a potential difference between the first III-V semiconductor material and the electrolyte, to electrochemically etch the sub-surface quantum structure (30) to form a plurality of nanostructures, while the surface layer (31) is not etched. A semiconductor structure, uses thereof, and devices incorporating such semiconductor structures are further provided.Type: ApplicationFiled: January 25, 2019Publication date: February 25, 2021Inventors: Rachel A. OLIVER, Tongtong ZHU, Yingjun LIU, Peter GRIFFIN
-
Publication number: 20200227255Abstract: A method for porosifying a Ill-nitride material in a semiconductor structure is provided, the semiconductor structure comprising a sub-surface structure of a first Ill-nitride material, having a charge carrier density greater than 5×1017 cm?3, beneath a surface layer of a second Ill-nitride material, having a charge carrier density of between 1×1014 cm?3 and 1×1017 cm?3. The method comprises the steps of exposing the surface layer to an electrolyte, and applying a potential difference between the first Ill-nitride material and the electrolyte, so that the sub-surface structure is porosified by electrochemical etching, while the surface layer is not porosified. A semiconductor structure and uses thereof are further provided.Type: ApplicationFiled: September 27, 2017Publication date: July 16, 2020Inventors: Tongtong ZHU, Rachel A. OLIVER, Yingjun LIU