Patents Assigned to RFHIC CORPORATION
  • Patent number: 11901417
    Abstract: Wafers including a diamond layer and a semiconductor layer having III-Nitride compounds and methods for fabricating the wafers are provided. A nucleation layer, at least one semiconductor layer having III-Nitride compound and a protection layer are formed on a silicon substrate. Then, a silicon carrier wafer is glass bonded to the protection layer. Subsequently the silicon substrate, nucleation layer and a portion of the semiconductor layer are removed. Then, an intermediate layer, a seed layer and a diamond layer are sequentially deposited on the III-Nitride layer. Next, a substrate wafer that includes a glass substrate (or a silicon substrate covered by a protection layer) is glass bonded to the diamond layer. Then, the silicon carrier wafer and the protection layer are removed.
    Type: Grant
    Filed: February 23, 2022
    Date of Patent: February 13, 2024
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11901418
    Abstract: Wafers including a diamond layer and a semiconductor layer having III-Nitride compounds and methods for fabricating the wafers are provided. A nucleation layer, at least one semiconductor layer having III-Nitride compound and a protection layer are formed on a silicon substrate. Then, a silicon carrier wafer is glass bonded to the protection layer. Subsequently the silicon substrate, nucleation layer and a portion of the semiconductor layer are removed. Then, an intermediate layer, a seed layer and a diamond layer are sequentially deposited on the III-Nitride layer. Next, a support wafer that includes a GaN layer (or a silicon layer covered by a protection layer) is deposited on the diamond layer. Then, the silicon carrier wafer and the protection layer are removed.
    Type: Grant
    Filed: February 23, 2022
    Date of Patent: February 13, 2024
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11652146
    Abstract: Wafers including a diamond layer and a semiconductor layer having III-Nitride compounds and methods for fabricating the wafers are provided. A nucleation layer, at least one semiconductor layer having III-Nitride compound and a protection layer are formed on a silicon substrate. Then, a silicon carrier wafer is glass bonded to the protection layer. Subsequently the silicon substrate, nucleation layer and a portion of the semiconductor layer are removed. Then, an intermediate layer, a seed layer and a first diamond layer are sequentially deposited on the III-Nitride layer. Next, the silicon carrier wafer and the protection layer are removed. Then, a silicon substrate wafer that includes a protection layer, silicon substrate and a diamond layer is prepared and glass bonded to the first diamond layer.
    Type: Grant
    Filed: June 10, 2020
    Date of Patent: May 16, 2023
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11521957
    Abstract: In one embodiment, a semiconductor device includes a first substrate with a transistor formed in a first active are, a first bonding pad electrically connected to the transistor and a first metal pad surrounding the first active area. A second substrate of a type that is different from the first substrate includes a passive circuit element in a second active area on a front surface, a second bonding pad electrically connected to the passive circuit element, a second metal pad surrounding the second active area, and a mounting pad on a back surface of the second substrate with a through-via electrically connecting the second bonding pad to the mounting pad. A first interconnection extends from the first bonding pad to the second bonding pad, and a second interconnection extends from the first metal pad to the second metal pad and surrounds the region through which the first interconnection extends.
    Type: Grant
    Filed: July 8, 2021
    Date of Patent: December 6, 2022
    Assignee: RFHIC CORPORATION
    Inventor: Won Sang Lee
  • Patent number: 11502175
    Abstract: Wafers including a diamond layer and a semiconductor layer having III-Nitride compounds and methods for fabricating the wafers are provided. A nucleation layer, at least one semiconductor layer having III-Nitride compound and a protection layer are formed on a silicon substrate. Then, a silicon carrier wafer is glass bonded to the protection layer. Subsequently the silicon substrate, nucleation layer and a portion of the semiconductor layer are removed. Then, an intermediate layer, a seed layer and a diamond layer are sequentially deposited on the III-Nitride layer. Next, a substrate wafer that includes a glass substrate (or a silicon substrate covered by a protection layer) is glass bonded to the diamond layer. Then, the silicon carrier wafer and the protection layer are removed.
    Type: Grant
    Filed: June 18, 2020
    Date of Patent: November 15, 2022
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11476335
    Abstract: Wafers including a diamond layer and a semiconductor layer having III-Nitride compounds and methods for fabricating the wafers are provided. A nucleation layer, at least one semiconductor layer having III-Nitride compound and a protection layer are formed on a silicon substrate. Then, a silicon carrier wafer is glass bonded to the protection layer. Subsequently the silicon substrate, nucleation layer and a portion of the semiconductor layer are removed. Then, an intermediate layer, a seed layer and a diamond layer are sequentially deposited on the III-Nitride layer. Next, a support wafer that includes a GaN layer (or a silicon layer covered by a protection layer) is deposited on the diamond layer. Then, the silicon carrier wafer and the protection layer are removed.
    Type: Grant
    Filed: June 29, 2020
    Date of Patent: October 18, 2022
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11424328
    Abstract: A method for fabricating a semiconductor wafer is provided, where the semiconductor wafer includes a diamond layer and a semiconductor layer having III-Nitride compounds. The method includes the steps of: disposing a nucleation layer on a SiC substrate and disposing at least one semiconductor layer on the nucleation layer, the at least one semiconductor layer including a III-Nitride compound. The method further includes the steps of: disposing a protection layer on the at least one semiconductor layer; bonding a carrier wafer to the protection layer, the carrier wafer including a SiC substrate; removing the substrate, the nucleation layer and a portion of the at least one semiconductor layer; disposing a diamond layer on the at least one semiconductor layer; depositing a substrate wafer on the diamond layer; and removing the carrier wafer and the protection layer.
    Type: Grant
    Filed: June 29, 2020
    Date of Patent: August 23, 2022
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 11146243
    Abstract: A bulk acoustic wave (BAW) filter for passing through electric signals in a preset frequency range is provided. The BAW filter includes: a diamond substrate; a passivation layer formed on the diamond substrate; a first metal layer formed on the passivation layer; a piezoelectric layer formed on the first metal layer; a second metal layer formed on a piezoelectric layer and a metal pad formed on the first metal layer. The metal pad, first metal layer, piezoelectric layer and second metal layer form an electrical path that allows an electrical signal within a preset frequency range to pass therethrough.
    Type: Grant
    Filed: February 2, 2020
    Date of Patent: October 12, 2021
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 10861947
    Abstract: Methods for processing a semiconductor transistor are provided, where the semiconductor transistor includes a substrate, an epitaxial layer, and transistor components that are formed on the epitaxial layer. The method includes: removing a portion of the substrate that is disposed below a portion of the transistor components, to thereby expose a portion of a bottom surface of the epitaxial layer; forming an electrically insulating layer on the exposed portion of the bottom surface of the epitaxial layer; forming a via that extends from a bottom surface of the insulating layer to a bottom surface of one of the transistor components; depositing at least one metal layer on the bottom surface of the insulating layer, on a side wall of the via and on the bottom surface of one of the transistor components; and applying a solder paste to a bottom surface of the at least one metal layer.
    Type: Grant
    Filed: May 26, 2020
    Date of Patent: December 8, 2020
    Assignee: RFHIC CORPORATION
    Inventor: Won Sang Lee
  • Publication number: 20200287004
    Abstract: Methods for processing a semiconductor transistor are provided, where the semiconductor transistor includes a substrate, an epitaxial layer, and transistor components that are formed on the epitaxial layer. The method includes: removing a portion of the substrate that is disposed below a portion of the transistor components, to thereby expose a portion of a bottom surface of the epitaxial layer; forming an electrically insulating layer on the exposed portion of the bottom surface of the epitaxial layer; forming a via that extends from a bottom surface of the insulating layer to a bottom surface of one of the transistor components; depositing at least one metal layer on the bottom surface of the insulating layer, on a side wall of the via and on the bottom surface of one of the transistor components; and applying a solder paste to a bottom surface of the at least one metal layer.
    Type: Application
    Filed: May 26, 2020
    Publication date: September 10, 2020
    Applicant: RFHIC Corporation
    Inventor: Won Sang Lee
  • Publication number: 20200227301
    Abstract: The present invention discloses a semiconductor-on-diamond-on-carrier substrate wafer. The semiconductor-on-diamond-on-carrier wafer comprises: a semiconductor-on-diamond wafer having a diamond side and semiconductor side; a carrier substrate disposed on the diamond side of the semiconductor-on-diamond wafer and including at least one layer having a lower coefficient of thermal expansion (CTE) than diamond; and an adhesive layer disposed between the diamond side of the semiconductor-on-diamond wafer and the carrier substrate to bond the carrier substrate to the semiconductor-on-diamond wafer. The semiconductor-on-diamond-on-carrier substrate wafer has the following characteristics: a total thickness variation of no more than 40 ?m; a wafer bow of no more than 100 ?m; and a wafer warp of no more than 40 ?m.
    Type: Application
    Filed: March 26, 2020
    Publication date: July 16, 2020
    Applicant: RFHIC Corporation
    Inventors: Daniel Francis, Frank Yantis Lowe, Michael Ian Pearson
  • Patent number: 10707311
    Abstract: HEMT having a drain field plate is provided. The drain field plate is formed in the area between the gate and drain of a HEMT. The drain field plate includes a metal pad that has a larger projection area than the drain pad. The drain field plate and semiconductor layer disposed beneath the drain field plate form a metal-semiconductor (M-S) Schottky structure. The capacitance of the M-S Schottky structure generates capacitance in the semiconductor area, which increases the breakdown voltage of the transistor components of the HEMT. A portion of the substrate under the active area may be removed to thereby increase the heat conductivity and reduce the junction temperature of the transistor components of the HEMT.
    Type: Grant
    Filed: December 1, 2018
    Date of Patent: July 7, 2020
    Assignee: RFHIC CORPORATION
    Inventor: Won Sang Lee
  • Patent number: 10699896
    Abstract: A method of fabricating a semiconductor device structure includes: providing a substrate comprising a layer of compound semiconductor material; forming a seed layer of nano-crystalline diamond having a layer thickness in a range 5 to 50 nm on the layer of compound semiconductor material; and growing a layer of polycrystalline CVD diamond on the seed layer using a chemical vapour deposition (CVD) technique. An effective thermal boundary resistance (TBReff) at an interface between the layer of compound semiconductor material and the layer of polycrystalline CVD diamond material is no more than 50 m2K/GW.
    Type: Grant
    Filed: April 14, 2019
    Date of Patent: June 30, 2020
    Assignee: RFHIC CORPORATION
    Inventors: Firooz Nasser-Faili, Daniel Francis, Frank Yantis Lowe, Daniel James Twitchen
  • Publication number: 20200177161
    Abstract: A bulk acoustic wave (BAW) filter for passing through electric signals in a preset frequency range is provided. The BAW filter includes: a diamond substrate; a passivation layer formed on the diamond substrate; a first metal layer formed on the passivation layer; a piezoelectric layer formed on the first metal layer; a second metal layer formed on a piezoelectric layer and a metal pad formed on the first metal layer. The metal pad, first metal layer, piezoelectric layer and second metal layer form an electrical path that allows an electrical signal within a preset frequency range to pass therethrough.
    Type: Application
    Filed: February 2, 2020
    Publication date: June 4, 2020
    Applicant: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 10594298
    Abstract: A bulk acoustic wave (BAW) filter for passing through electric signals in a preset frequency range is provided. The BAW filter includes: a diamond substrate; a passivation layer formed on the diamond substrate; a first metal layer formed on the passivation layer; a piezoelectric layer formed on the first metal layer; a second metal layer formed on a piezoelectric layer and a metal pad formed on the first metal layer. The metal pad, first metal layer, piezoelectric layer and second metal layer form an electrical path that allows an electrical signal within a preset frequency range to pass therethrough.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: March 17, 2020
    Assignee: RFHIC Corporation
    Inventor: Won Sang Lee
  • Patent number: 10586850
    Abstract: Methods for mounting and dismounting thin and/or bowed semiconductor-on-diamond wafers to a carrier are disclosed that flatten said wafers and provide mechanical support to enable efficient semiconductor device processing on said semiconductor-on-diamond wafers.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: March 10, 2020
    Assignee: RFHIC Corporation
    Inventors: Quentin Diduck, Daniel Francis, Frank Yantis Lowe, Felix Ejeckam
  • Patent number: 10446468
    Abstract: Methods of fabricating compound semiconductor device structures having polycrystalline CVD diamond. The method includes: providing a substrate that has a layer of single crystal compound semiconductor material; forming a bonding layer on a surface of the substrate, the bonding layer having a thickness of less than 25 nm and a thickness variation of no more than 15 nm; and growing a layer of polycrystalline diamond on the bonding layer using a chemical vapor deposition technique. The effective thermal boundary resistance at the interface between the layer of single crystal compound semiconductor material and the layer of polycrystalline CVD diamond material is less than 25 m2K/GW. The layer of single crystal compound semiconductor material has one or both of the following characteristics: a charge mobility of at least 1200 cm2V?1s?1; and a sheet resistance of no more than 700 ?/square.
    Type: Grant
    Filed: February 24, 2019
    Date of Patent: October 15, 2019
    Assignee: RFHIC CORPORATION
    Inventors: Frank Yantis Lowe, Daniel Francis, Firooz Nasser-Faili, Daniel James Twitchen
  • Publication number: 20190252183
    Abstract: A method of fabricating a semiconductor device structure includes: providing a substrate comprising a layer of compound semiconductor material; forming a seed layer of nano-crystalline diamond having a layer thickness in a range 5 to 50 nm on the layer of compound semiconductor material; and growing a layer of polycrystalline CVD diamond on the seed layer using a chemical vapour deposition (CVD) technique. An effective thermal boundary resistance (TBReff) at an interface between the layer of compound semiconductor material and the layer of polycrystalline CVD diamond material is no more than 50 m2K/GW.
    Type: Application
    Filed: April 14, 2019
    Publication date: August 15, 2019
    Applicant: RFHIC Corporation
    Inventors: Firooz NASSER-FAILI, Daniel Francis, Frank Yantis Lowe, Daniel James Twitchen
  • Publication number: 20190189533
    Abstract: A semiconductor device structure comprising: a layer of single crystal compound semiconductor material; and a layer of polycrystalline CVD diamond material, wherein the layer of polycrystalline CVD diamond material is bonded to the layer of single crystal compound semiconductor material via a bonding layer having a thickness of less than 25 nm and a thickness variation of no more than 15 nm, wherein an effective thermal boundary resistance (TBReff) as measured by transient thermoreflectance at an interface between the layer of single crystal compound semiconductor material and the layer of polycrystalline CVD diamond material is less than 25 m2 K/GW with a variation of no more than 12 m2 K/GW as measured across the semiconductor device structure, and wherein the layer of single crystal compound semiconductor material has one or both of the following characteristics: a charge mobility of at least 1200 cm2 V?1 s?1; and a sheet resistance of no more than 700 ?/square.
    Type: Application
    Filed: February 24, 2019
    Publication date: June 20, 2019
    Applicant: RFHIC Corporation
    Inventors: Frank Yantis LOWE, Daniel Francis, Firooz NASSER-FAILI, Daneil James Twitchen
  • Patent number: 10319580
    Abstract: A semiconductor device structure comprising: a layer of compound semiconductor material; and a layer of polycrystalline CVD diamond material, wherein the layer of polycrystalline CVD diamond material is bonded to the layer of compound semiconductor material via a layer of nano-crystalline diamond which is directly bonded to the layer of compound semiconductor material, the layer of nano-crystalline diamond having a thickness in a range 5 to 50 nm and configured such that an effective thermal boundary resistance (TBReff) as measured by transient thermoreflectance at an interface between the layer of compound semiconductor material and the layer of polycrystalline CVD diamond material is no more than 50 m2K/GW.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: June 11, 2019
    Assignee: RFHIC CORPORATION
    Inventors: Firooz Nasser-Faili, Daniel Francis, Frank Yantis Lowe, Daniel James Twitchen