Patents by Inventor Douglas Tweet

Douglas Tweet 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: 20060073708
    Abstract: Transistors fabricated on SSOI (Strained Silicon On Insulator) substrate, which comprises a strained silicon layer disposed directly on an insulator layer, have enhanced device performance due to the strain-induced band modification of the strained silicon device channel and the limited silicon volume because of the insulator layer. The present invention discloses SSOI substrate fabrication processes comprising various novel approaches. One is the use of a thin relaxed SiGe layer as the strain-induced seed layer to facilitate integration and reduce processing cost. Another is the formation of split implant microcracks deep in the silicon substrate to reduce the number of threading dislocations reaching the strained silicon layer. And lastly is a two step annealing/thinning process for the strained silicon/SiGe multilayer film transfer without blister or flaking formation.
    Type: Application
    Filed: November 21, 2005
    Publication date: April 6, 2006
    Inventors: Jer-shen Maa, Jong-Jan Lee, Douglas Tweet, David Evans, Allen Burmaster, Sheng Hsu
  • Publication number: 20060051960
    Abstract: A method of forming a relaxed SiGe layer having a high germanium content in a semiconductor device includes preparing a silicon substrate; depositing a strained SiGe layer; implanting ions into the strained SiGe layer, wherein the ions include silicon ions and ions selected from the group of ions consisting of boron and helium, and which further includes implanting H+ ions; annealing to relax the strained SiGe layer, thereby forming a first relaxed SiGe layer; and completing the semiconductor device.
    Type: Application
    Filed: September 7, 2004
    Publication date: March 9, 2006
    Inventors: Douglas Tweet, David Evans, Sheng Hsu, Jer-Shen Maa
  • Publication number: 20060046507
    Abstract: A method of providing a layer in a semiconductor device, wherein the layer includes Si1-x-yGexCy, and wherein the carbon in the layer is in a stable condition, includes preparing a silicon substrate; preparing a SiGeC precursor; forming a Si1-x-yGexCy layer on the silicon substrate from the precursor; forming a top silicon layer on the Si1-x-yGexCy layer; and completing the semiconductor device.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventor: Douglas Tweet
  • Publication number: 20060030124
    Abstract: A method of fabricating a silicon-on-plastic layer via layer transfer includes depositing a layer of SiGe on a silicon substrate; depositing a layer of silicon; implanting splitting hydrogen ions into the silicon substrate; bonding a glass substrate to the silicon layer; splitting the wafer; removing the silicon layer and a portion of the SiGe layer; depositing a dielectric on the silicon side of the silicon-on-glass wafer; applying adhesive and bonding a plastic substrate to the silicon side of the silicon-on-glass wafer; removing the glass from the glass side of the bonded, silicon-on-glass wafer to form a silicon-on-plastic wafer; and completing a desired IC device on the silicon-on-plastic. Multi-level structure may be fabricated according to the method of the invention by repeating the last few steps of the method of the invention.
    Type: Application
    Filed: August 5, 2004
    Publication date: February 9, 2006
    Inventors: Jer-Shen Maa, Jong-Jan Lee, Douglas Tweet, Sheng Hsu
  • Publication number: 20060019464
    Abstract: A method of fabricating a silicon-on-glass layer via layer transfer includes depositing a layer of SiGe on a silicon substrate; relaxing the SiGe layer; depositing a layer of silicon on the relaxed SiGe layer; implanting hydrogen ions in a second hydrogen implantation step to facilitate splitting of the wafer; bonding a glass substrate to the strained silicon layer to form a composite wafer; splitting the composite wafer to provide a split wafer; and processing the split wafer to prepare it for subsequent device fabrication.
    Type: Application
    Filed: July 20, 2004
    Publication date: January 26, 2006
    Inventors: Jer-Shen Maa, Jong-Jan Lee, Douglas Tweet, Sheng Hsu
  • Publication number: 20050214997
    Abstract: A method of forming a substrate for use in IC device fabrication includes preparing a silicon substrate, including doping a bulk silicon (100) substrate with ions taken from the group of ions to form a doped substrate taken from the group of doped substrates consisting of n-type doped substrates and p-type doped substrates; forming a first relaxed SiGe layer on the silicon substrate; forming a first tensile-strained silicon cap on the first relaxed SiGe layer; forming a second relaxed SiGe layer on the first tensile-strained silicon cap; forming a second tensile-strained silicon cap on the second relaxed SiGe layer; and completing an IC device.
    Type: Application
    Filed: March 23, 2004
    Publication date: September 29, 2005
    Inventors: Douglas Tweet, Sheng Hsu, Jer-Shen Maa
  • Publication number: 20050196894
    Abstract: A 3D quantum dot optical path structure is provided, along with a method for selectively forming a 3D quantum dot optical path. The method comprises: forming a single crystal Si substrate with a surface; forming a Si feature in the substrate, such as a via, trench, or pillar; forming dots from a Ge or SiGe material overlying the Si feature; and, forming an optical path that includes the dots. In some aspects of the method, the Si feature has defect sites. For example, the Si feature may be formed with a miscut angle. As a result of the miscut angle, steps are formed in the Si feature plane. Then, the dots are formed in the Si feature steps. The miscut angle is in the range between 0.1 and 5 degrees, and the spacing between steps is in the range between 1 and 250 nanometers (nm).
    Type: Application
    Filed: March 3, 2004
    Publication date: September 8, 2005
    Inventors: Jer-Shen Maa, Jong-Jan Lee, Douglas Tweet, Sheng Hsu
  • Publication number: 20050181592
    Abstract: A method of forming a SiGe layer having a relatively high Ge content includes preparing a silicon substrate; depositing a layer of SiGe to a thickness of between about 100 nm to 500 nm, wherein the Ge content of the SiGe layer is equal to or greater than 10%, implanting H2+ ions through the SiGe layer into the substrate at a dose of between about 2×1014 cm?2 to 2×1016 cm?2, at an energy of between about 20 keV to 100+ keV; low temperature thermal annealing at a temperature of between about 200° C. to 400° C. for between about ten minutes and ten hours; high temperature thermal annealing the substrate and SiGe layer, to relax the SiGe layer, in an inert atmosphere at a temperature of between about 650° C. to 1000° C. for between about 30 seconds and 30 minutes; and depositing a layer of silicon-based material on the relaxed SiGe layer to a thickness of between about 5 nm to 30 nm.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 18, 2005
    Inventors: Douglas Tweet, Jong-Jan Lee, Jer-Shen Maa
  • Publication number: 20050151134
    Abstract: A dual gate strained-Si MOSFET with thin SiGe dislocation regions and a method for fabricating the same are provided. The method comprises: forming a first layer of relaxed SiGe overlying a substrate, having a thickness of less than 5000 ?; forming a second layer of relaxed SiGe overlying the substrate and adjacent to the first layer of SiGe, having a thickness of less than 5000 ?; forming a layer of strained-Si overlying the first and second SiGe layers; forming a shallow trench isolation region interposed between the first SiGe layer and the second SiGe layer; forming an n-well in the substrate and the overlying first layer of SiGe; forming a p-well in the substrate and the overlying second layer of SiGe; forming channel regions, in the strained-Si, and forming PMOS and NMOS transistor source and drain regions.
    Type: Application
    Filed: March 3, 2005
    Publication date: July 14, 2005
    Inventors: Sheng Hsu, Jong-Jan Lee, Douglas Tweet, Jer-shen Maa
  • Publication number: 20050153474
    Abstract: Provided are a SiGe vertical optical path and a method for selectively forming a SiGe optical path normal structure for IR photodetection. The method comprises: forming a Si substrate surface; forming a Si feature, normal with respect to the Si substrate surface, such as a trench, via, or pillar; and, selectively forming a SiGe optical path overlying the Si normal feature. In some aspects, the Si substrate surface is formed a first plane and the Si normal feature has walls (sidewalls), normal with respect to the Si substrate surface, and a surface in a second plane, parallel to the first plane. Then, selectively forming a SiGe optical path overlying the Si normal feature includes forming a SiGe vertical optical path overlying the normal feature walls.
    Type: Application
    Filed: January 12, 2004
    Publication date: July 14, 2005
    Inventors: Douglas Tweet, Jong-Jan Lee, Jer-Shen Maa, Sheng Hsu
  • Publication number: 20050153524
    Abstract: Transistors fabricated on SSOI (Strained Silicon On Insulator) substrate, which comprises a strained silicon layer disposed directly on an insulator layer, have enhanced device performance due to the strain-induced band modification of the strained silicon device channel and the limited silicon volume because of the insulator layer. The present invention discloses a SSOI substrate fabrication process comprising various novel approaches. One is the use of a thin relaxed SiGe layer as the strain-induced seed layer to facilitate integration and reduce processing cost. Another is the formation of split implant microcracks deep in the silicon substrate to reduce the number of threading dislocations reaching the strained silicon layer. And lastly is the two step annealing/thinning process for the strained silicon/SiGe multilayer film transfer without blister or flaking formation.
    Type: Application
    Filed: January 12, 2004
    Publication date: July 14, 2005
    Inventors: Jer-shen Maa, Jong-Jan Lee, Douglas Tweet, David Evans, Allen Burmaster, Sheng Hsu
  • Publication number: 20050133723
    Abstract: A SiGe surface-normal optical path photodetector structure and a method for forming the SiGe optical path normal structure are provided. The method comprises: forming a Si substrate with a surface; forming a Si feature, normal with respect to the Si substrate surface, such as a via, trench, or pillar; depositing SiGe overlying the Si normal feature to a thickness in the range of 5 to 1000 nanometers (nm); and, forming a SiGe optical path normal structure having an optical path length in the range of 0.1 to 10 microns. Typically, the SiGe has a Ge concentration in the range from 5 to 100%. The Ge concentration may be graded to increase with respect to the deposition thickness. For example, the SiGe may have a 20% concentration of Ge at the Si substrate interface, a 30% concentration of Ge at a SiGe film top surface, and a thickness of 400 nm.
    Type: Application
    Filed: December 23, 2003
    Publication date: June 23, 2005
    Inventors: Jong Lee, Jer-Shen Maa, Douglas Tweet, Sheng Hsu
  • Publication number: 20050070115
    Abstract: A method of forming a silicon-germanium layer on an insulator includes depositing a layer of silicon-germanium on a silicon substrate to form a silicon/silicon-germanium portion; implanting hydrogen ions into the silicon substrate between about 500 ? to 1 ?m below a silicon-germanium/silicon interface; bonding the silicon/silicon-germanium portion to an insulator substrate to form a couplet; thermally annealing the couplet in a first thermal annealing step to split the couplet; patterning and etching the silicon-germanium-on-insulator portion to remove portions of the silicon and SiGe layers; etching the silicon-germanium-on-insulator portion to remove the remaining silicon layer; thermally annealing the silicon-germanium-on-insulator portion in a second annealing step to relaxed the SiGe layer; and depositing a layer of strained silicon about the SiGe layer.
    Type: Application
    Filed: September 30, 2003
    Publication date: March 31, 2005
    Inventors: Jer-Shen Maa, Jong-Jan Lee, Douglas Tweet, Sheng Hsu