Patents Assigned to Silicon Wafer Technologies, Inc.
  • Patent number: 6861320
    Abstract: The invention provides a method of making silicon-on-insulator SOI substrates with nitride buried insulator layer by implantation of molecular deuterated ammonia ions ND3+, instead of implanting nitrogen ions (N+, or N2+) as is done in prior art nitride SOI processes. The resultant structure, after annealing, has a buried insulator with a defect density which is substantially lower than in prior art nitride SOI. The deuterated nitride SOI substrates allow much better heat dissipation than SOI with a silicon dioxide buried insulator. These substrates can be used for manufacturing of high speed and high power dissipation monolithic integrated circuits.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: March 1, 2005
    Assignee: Silicon Wafer Technologies, Inc.
    Inventor: Alexander Usenko
  • Patent number: 6806171
    Abstract: A technique for forming a film of crystalline material, preferably silicon. The technique creates a sandwich structure with a weakened region at a selected depth underneath the surface. The weakened region is a layer of porous silicon with high porosity. The high porosity enclosed layer is formed by (1) forming a porous silicon layer with low porosity on surface of the substrate, (2) epitaxial growth of a non-porous layer over the low-porous layer (3) increasing of porosity of the low-porous layer making the said layer hi-porous, (4) cleaving the semiconductor substrate at said high porous layer. The porosity of the buried low-porous layer is increased by hydrogenation techniques, for example, by processing in hydrogen plasma. The process is preferentially used to produce silicon-on-insulator wafers.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: October 19, 2004
    Assignee: Silicon Wafer Technologies, Inc.
    Inventors: Alexander Ulyashin, Alexander Usenko
  • Patent number: 6696352
    Abstract: A process for producing a multilayered substrate. In a first step, an adhesive layer is applied to a surface of a support substrate. Then a device substrate is placed into contact with the adhesive surface. Then the adhesive is cured. Then the device substrate is thinned. The device substrate has a hydrogen trap layer inside. The trap layer is formed by ion implantation through a face surface of the device substrate. The adhesive is chosen from compounds that release hydrogen upon curing. Thinning of the device substrate is performed by cleavage along a fragile layer of hydrogen microbubbles. The microbubble layer is formed through gettering of hydrogen released from the adhesive layer upon curing onto the trap layer and evolving the trapped hydrogen into the microbubbles. The substrates are preferably silicon single crystalline wafers and the adhesive is preferably hydrogen-silsesquioxane.
    Type: Grant
    Filed: July 24, 2002
    Date of Patent: February 24, 2004
    Assignee: Silicon Wafer Technologies, Inc.
    Inventors: William Carr, Alexander Usenko
  • Patent number: 6387829
    Abstract: A process for manufacturing a silicon-on-insulator wafer from a silicon wafer assembly. The assembly is made of two wafers. One of the wafers contains a fragile layer. The fragile layer is a layer containing a high amount of hydrogen. An amount of energy from an energy source is applied to the assembly to separate the assembly along the fragile layer thus forming a silicon-on-insulator wafer and a leftover wafer. The energy source is selected from the group consisting of: ultrasound, infrared, hydrostatic pressure, hydrodynamic pressure, or mechanical energy. The amount of energy is chosen to be sufficient to transform the fragile layer into a quasi-continuous gaseous layer. Under separation the hydrogen-enriched layer transforms into layer consisting of hydrogen platelets and hydrogen microbubbles.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: May 14, 2002
    Assignee: Silicon Wafer Technologies, Inc.
    Inventors: Alexander Yuri Usenko, William Ned Carr
  • Patent number: 6368938
    Abstract: A process for manufacturing a silicon-on-insulator substrate and semiconductor devices on said substrate from thermally oxidized silicon wafer so that processing temperatures are limited to 900° C. is disclosed. The substrate is fabricated using H2 split process. Processing temperatures are limited to temperature of initiating of out-diffusion of oxygen from silicon dioxide into silicon. The limit prevents deterioration of buried oxide, and the oxide has low hole trap density that is equal to the trap density of an initial thermal silicon dioxide. Processing temperatures after implantation for H2 split process are limited to temperature of stability of dislocation microloops induced by the implantation at its damage peak. Resulting SOI structure have a gettering layer made from the microloops. The getter prevents yield drop caused by heavy metal contamination during the fabrication. Finished SOI devices have improved gate oxide integrity.
    Type: Grant
    Filed: June 7, 2000
    Date of Patent: April 9, 2002
    Assignee: Silicon Wafer Technologies, Inc.
    Inventor: Alexander Yuri Usenko
  • Patent number: 6355493
    Abstract: A method for forming ICs comprising a highly-resistive or semi-insulating semiconductor substrate having a thin, low resistance active semiconductor layer thereon. In accordance with one embodiment of the method, the entire semiconductor substrate with at least partially prefabricated semiconductor devices disposed thereon is subjected to irradiation sufficient to impart high resistance throughout the substrate and active semiconductor layer. A thin, low resistance, active semiconductor layer is then generated on the substrate body by localized annealing. The (partially) prefabricated semiconductor devices are restored to operability by virtue of the annealing step as defects in the top insulating layers and properties of thin layers underneath the insulator-semiconductor interfaces are “healed.” The annealing step does not, however, heal the defects in the bulk substrate so that it remains semi-insulating.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: March 12, 2002
    Assignee: Silicon Wafer Technologies Inc.
    Inventor: Alexander Yuri Usenko
  • Patent number: 6352909
    Abstract: Process for lift-off of a thin layer from a crystalline substrate, preferably the layer from a silicon wafer to further form a silicon-on-insulator (SOI) sandwich structure, wherein a separative interlayer comprises a thin quasi-continuous gaseous layer and said interlayer is obtained by gettering a monatomic hydrogen into a preformed buried defect-rich layer preferably obtained by implantation. The monatomic hydrogen is preferably inserted into the substrate by electrolytic means.
    Type: Grant
    Filed: May 26, 2000
    Date of Patent: March 5, 2002
    Assignee: Silicon Wafer Technologies, Inc.
    Inventor: Alexander Yuri Usenko
  • Patent number: 6346459
    Abstract: The method of the invention causes fracture of a semiconductor layer containing semiconductor devices from a support layer and requires no masking of the semiconductor device features during an implantation action. The method initially implants protons throughout an entirety of the semiconductor layer at an energy level that enables the protons to reach a depth that defines a delamination region. The implanting creating defects in the semiconductor devices and charge accumulation in dielectric portions (if any). Next a heat treating step causes a delamination of the semiconductor layer from the support layer that lies beneath the delamination region. Then the semiconductor layer is annealed at a temperature that exceeds a thermal stability temperature of the defects to cause a healing thereof.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: February 12, 2002
    Assignee: Silicon Wafer Technologies, Inc.
    Inventors: Alexander Y Usenko, William N. Carr