Patents by Inventor H. Zhang

H. Zhang 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: 20150228777
    Abstract: Transistors having partially recessed gates are constructed on silicon-on-insulator (SOI) semiconductor wafers provided with a buried oxide layer (BOX), for example, FD-SOI and UTBB devices. An epitaxially grown channel region relaxes constraints on the design of doped source and drain profiles. Formation of a partially recessed gate and raised epitaxial source and drain regions allow further improvements in transistor performance and reduction of short channel effects such as drain induced barrier lowering (DIBL) and control of a characteristic subthreshold slope. Gate recess can be varied to place the channel at different depths relative to the dopant profile, assisted by advanced process control. The partially recessed gate has an associated high-k gate dielectric that is initially formed in contact with three sides of the gate. Subsequent removal of the high-k sidewalls and substitution of a lower-k silicon nitride encapsulant lowers capacitance between the gate and the source and drain regions.
    Type: Application
    Filed: February 7, 2014
    Publication date: August 13, 2015
    Applicant: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Patent number: 9099465
    Abstract: Metal interconnections are formed in an integrated circuit by forming a wide trench in a dielectric layer. A dielectric fin of a second dielectric material is formed in the trench. Conductive plugs and metal lines are formed on both sides of the fin.
    Type: Grant
    Filed: October 14, 2013
    Date of Patent: August 4, 2015
    Assignee: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Publication number: 20150162278
    Abstract: Ultra-low-k dielectric materials used as inter-layer dielectrics in high-performance integrated circuits are prone to be structurally unstable. The Young's modulus of such materials is decreased, resulting in porosity, poor film strength, cracking, and voids. An alternative dual damascene interconnect structure incorporates deep air gaps into a high modulus dielectric material to maintain structural stability while reducing capacitance between adjacent nanowires. Incorporation of a deep air gap having k=1.0 compensates for the use of a higher modulus film having a dielectric constant greater than the typical ultra-low-k (ULK) dielectric value of about 2.2. The higher modulus film containing the deep air gap is used as an insulator and a means of reducing fringe capacitance between adjacent metal lines. The dielectric layer between two adjacent metal lines thus forms a ULK/high-modulus dielectric bi-layer.
    Type: Application
    Filed: December 5, 2013
    Publication date: June 11, 2015
    Applicants: International Business Machines Corporation, STMicroelectronics, Inc.
    Inventors: John H. Zhang, Hsueh-Chung Chen, Lawrence A. Clevenger, Yann Mignot, Carl Radens, Richard Stephen Wise, Yannick Loquet, Yiheng Xu
  • Publication number: 20150162277
    Abstract: Ultra-low-k dielectric materials used as inter-layer dielectrics in high-performance integrated circuits are prone to be structurally unstable. The Young's modulus of such materials is decreased, resulting in porosity, poor film strength, cracking, and voids. An alternative dual damascene interconnect structure incorporates air gaps into a high modulus dielectric material to maintain structural stability while reducing capacitance between adjacent nanowires. Incorporation of an air gap having k=1.0 compensates for the use of a higher modulus film having a dielectric constant greater than the typical ultra-low-k (ULK) dielectric value of about 2.2. The higher modulus film containing the air gap is used as an insulator between adjacent metal lines, while a ULK film is retained to insulate vias. The dielectric layer between two adjacent metal lines thus forms a ULK/high-modulus dielectric bi-layer.
    Type: Application
    Filed: December 5, 2013
    Publication date: June 11, 2015
    Applicants: International Business Machines Corporation, STMicroelectronics, Inc.
    Inventors: John H. Zhang, Yann Mignot, Lawrence A. Clevenger, Carl Radens, Richard Stephen Wise, Yiheng Xu, Yannick Loquet, Hsueh-Chung Chen
  • Publication number: 20150115401
    Abstract: A sequence of semiconductor processing steps permits formation of both vertical and horizontal nanometer-scale serpentine resistors and parallel plate capacitors within a common structure. The method of fabricating such a structure cleverly takes advantage of a CMP process non-uniformity in which the CMP polish rate of an insulating material varies according to a certain underlying topography. By establishing such topography underneath a layer of the insulating material, different film thicknesses of the insulator can be created in different areas by leveraging differential polish rates, thereby avoiding the use of a lithography mask. In one embodiment, a plurality of resistors and capacitors can be formed as a compact integrated structure within a common dielectric block, using a process that requires only two mask layers.
    Type: Application
    Filed: October 31, 2013
    Publication date: April 30, 2015
    Inventors: John H. Zhang, Lawrence A. Clevenger, Carl Radens, Yiheng Xu, Edem Wornyo
  • Patent number: 9018092
    Abstract: A plurality of metal tracks are formed in an integrated circuit die in three metal layers stacked within the die. A protective dielectric layer is formed around metal tracks of an intermediate metal layer. The protective dielectric layer acts as a hard mask to define contact vias between metal tracks in the metal layers above and below the intermediate metal layer.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: April 28, 2015
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: John H. Zhang, Lawrence A. Clevenger, Carl Radens, Yiheng Xu
  • Publication number: 20150102496
    Abstract: Metal interconnections are formed in an integrated circuit by forming a wide trench in a dielectric layer. A dielectric fin of a second dielectric material is formed in the trench. Conductive plugs and metal lines are formed on both sides of the fin.
    Type: Application
    Filed: October 14, 2013
    Publication date: April 16, 2015
    Applicant: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Publication number: 20150097289
    Abstract: A sequence of processing steps presented herein is used to embed an optical signal path within an array of nanowires, using only one lithography step. Using the techniques disclosed, it is not necessary to mask electrical features while forming optical features, and vice versa. Instead, optical and electrical signal paths can be created substantially simultaneously in the same masking cycle. This is made possible by a disparity in the widths of the respective features, the optical signal paths being significantly wider than the electrical ones. Using a damascene process, the structures of disparate widths are plated with metal that over-fills narrow trenches and under-fills a wide trench. An optical cladding material can then be deposited into the trench so as to surround an optical core for light transmission.
    Type: Application
    Filed: October 3, 2013
    Publication date: April 9, 2015
    Applicant: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Publication number: 20150096591
    Abstract: A brush-cleaning apparatus is disclosed for use in cleaning a semiconductor wafer after polishing. Embodiments of the brush-cleaning apparatus implemented with a multi-branch chemical dispensing unit are applied beneficially to clean semiconductor wafers, post-polish, using a hybrid cleaning method. An exemplary hybrid cleaning method employs a two-chemical sequence in which first and second chemical treatment modules are separate from one another, and are followed by a pH-neutralizing-rinse that occurs in a treatment module separate from the first and second chemical treatment modules. Implementation of such hybrid methods is facilitated by the multi-branch chemical dispensing unit, which provides separate chemical lines to different chemical treatment modules, and dispenses chemical to at least four different areas of each wafer during single-wafer processing in an upright orientation.
    Type: Application
    Filed: October 7, 2013
    Publication date: April 9, 2015
    Applicant: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Patent number: 9002493
    Abstract: A semiconductor processing apparatus includes a semiconductor processing station for a semiconductor wafer, and an endpoint detector associated with the semiconductor processing station. The endpoint detector includes a non-contact probe configured to probe the semiconductor wafer, an optical transmitter configured to transmit an optical signal to the non-contact probe, and an optical receiver configured to receive a reflected optical signal from the non-contact probe. The controller controls the semiconductor processing station based on the reflected optical signal.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: April 7, 2015
    Assignee: STMicroelectronics, Inc.
    Inventors: John H. Zhang, Cindy Goldberg
  • Patent number: 8992692
    Abstract: A cleaning apparatus for cleaning a semiconductor wafer includes a rotary brush to be positioned to clean the semiconductor wafer, and an optical sensing device associated with the rotary brush to sense a separation distance between a reference position thereon and the semiconductor wafer. An actuator is coupled to the optical sensing device to position the rotary brush based upon the sensed separation distance.
    Type: Grant
    Filed: February 3, 2012
    Date of Patent: March 31, 2015
    Assignee: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Publication number: 20150087205
    Abstract: An adaptive uniform polishing system is equipped with feedback control to apply localized adjustments during a polishing operation. The adaptive uniform polishing system disclosed has particular application to the semiconductor industry. Such an adaptive uniform polishing system includes a rotatable head that holds a semiconductor wafer, and a processing unit structured to be placed in contact with an exposed surface of the wafer. The processing unit includes a rotatable macro-pad and a plurality of rotatable micro-pads that can polish different portions of the exposed surface at different rotation speeds and pressures. Thus, uniformity across the exposed surface can be enhanced by applying customized treatments to different areas. Customized treatments can include the use of different pad materials and geometries. Parameters of the adaptive uniform polishing system are programmable, based on in-situ data or data from other operations in a fabrication process, using advanced process control.
    Type: Application
    Filed: September 24, 2013
    Publication date: March 26, 2015
    Applicant: STMicroelectronics, Inc.
    Inventor: John H. Zhang
  • Patent number: 8987780
    Abstract: A graphene capped HEMT device and a method of fabricating same are disclosed. The graphene capped HEMT device includes one or more graphene caps that enhance device performance and/or reliability of an exemplary AlGaN/GaN heterostructure transistor used in high-frequency, high-energy applications, e.g., wireless telecommunications. The HEMT device disclosed makes use of the extraordinary material properties of graphene. One of the graphene caps acts as a heat sink underneath the transistor, while the other graphene cap stabilizes the source, drain, and gate regions of the transistor to prevent cracking during high-power operation. A process flow is disclosed for replacing a three-layer film stack, previously used to prevent cracking, with a one-atom thick layer of graphene, without otherwise degrading device performance. In addition, the HEMT device disclosed includes a hexagonal boron nitride adhesion layer to facilitate deposition of the compound nitride semiconductors onto the graphene.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: March 24, 2015
    Assignee: STMicroelectronics, Inc.
    Inventors: John H Zhang, Cindy Goldberg, Walter Kleemeier
  • Patent number: 8970004
    Abstract: A junction diode array is disclosed for use in protecting integrated circuits from electrostatic discharge. The junction diodes integrate symmetric and asymmetric junction diodes of various sizes and capabilities. Some of the junction diodes are configured to provide low voltage and current discharge via un-encapsulated interconnecting wires, while others are configured to provide high voltage and current discharge via encapsulated interconnecting wires. Junction diode array elements include p-n junction diodes and N+/N++ junction diodes. The junction diodes include implanted regions having customized shapes. If both symmetric and asymmetric diodes are not needed as components of the junction diode array, the array is configured with isolation regions between diodes of either type. Some junction diode arrays include a buried oxide layer to prevent diffusion of dopants into the substrate beyond a selected depth.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: March 3, 2015
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: John H. Zhang, Lawrence A. Clevenger, Carl Radens, Yiheng Xu
  • Publication number: 20150053930
    Abstract: Energy bands of a thin film containing molecular clusters are tuned by controlling the size and the charge of the clusters during thin film deposition. Using atomic layer deposition, an ionic cluster film is formed in the gate region of a nanometer-scale transistor to adjust the threshold voltage, and a neutral cluster film is formed in the source and drain regions to adjust contact resistance. A work function semiconductor material such as a silver bromide or a lanthanum oxide is deposited so as to include clusters of different sizes such as dimers, trimers, and tetramers, formed from isolated monomers. A type of Atomic Layer Deposition system is used to deposit on semiconductor wafers molecular clusters to form thin film junctions having selected energy gaps. A beam of ions contains different ionic clusters which are then selected for deposition by passing the beam through a filter in which different apertures select clusters based on size and orientation.
    Type: Application
    Filed: August 20, 2014
    Publication date: February 26, 2015
    Inventor: John H. Zhang
  • Publication number: 20150002213
    Abstract: Nanoscale efuses, antifuses, and planar coil inductors are disclosed. A copper damascene process can be used to make all of these circuit elements. A low-temperature copper etch process can be used to make the efuses and efuse-like inductors. The circuit elements can be designed and constructed in a modular fashion by linking a matrix of metal columns in different configurations and sizes. The number of metal columns, or the size of a dielectric mesh included in the circuit element, determines its electrical characteristics. Alternatively, the efuses and inductors can be formed from interstitial metal that is either deposited into a matrix of dielectric columns, or left behind after etching columnar openings in a block of metal. Arrays of metal columns also serve a second function as features that can improve polish uniformity in place of conventional dummy structures. Use of such modular arrays provides flexibility to integrated circuit designers.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 1, 2015
    Inventors: John H. Zhang, Lawrence A. Clevenger, Carl Radens, Yiheng Xu, Edem Wornyo
  • Publication number: 20150005610
    Abstract: It is recognized that, because of its unique properties, graphene can serve as an interface with biological cells that communicate by an electrical impulse, or action potential. Responding to a sensed signal can be accomplished by coupling a graphene sensor to a low power digital electronic switch that is activatable by the sensed low power electrical signals. It is further recognized that low power devices such as tunneling diodes and TFETs are suitable for use in such biological applications in conjunction with graphene sensors. While tunneling diodes can be used in diagnostic applications, TFETs, which are three-terminal devices, further permit controlling the voltage on one cell according to signals received by other cells. Thus, by the use of a biological sensor system that includes graphene nanowire sensors coupled to a TFET, charge can be redistributed among different biological cells, potentially with therapeutic effects.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 1, 2015
    Inventor: John H. Zhang
  • Publication number: 20150001583
    Abstract: An integrated circuit die includes a silicon substrate. PMOS and NMOS transistors are formed on the silicon substrate. The carrier mobilities of the PMOS and NMOS transistors are increased by introducing tensile stress to the channel region of the NMOS transistors and compressive stress to the channel regions of the PMOS transistors. Tensile stress is introduced by including a region of SiGe below the channel region of the NMOS transistors. Compressive stress is introduced by including regions of SiGe in the source and drain regions of the PMOS transistors.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 1, 2015
    Inventors: John H. Zhang, Pietro Montanini
  • Patent number: 8921976
    Abstract: Passive circuit elements are formed at surfaces of two integrated circuit wafers. The passive circuit elements are utilized to align the two integrated circuit wafers to form an integrated circuit wafer stack.
    Type: Grant
    Filed: December 13, 2011
    Date of Patent: December 30, 2014
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: John H. Zhang, Lawrence A. Clevenger, Yiheng Xu
  • Patent number: 8907427
    Abstract: A semiconductor device may include a substrate, source and drain regions in the substrate, a recessed epitaxial channel layer in the substrate between the source and drain regions, and a high-K gate dielectric layer overlying the recessed epitaxial channel layer. The semiconductor device may further include a gate electrode overlying the high-K gate dielectric layer, a dielectric cap layer in contact with top and sidewall portions of the gate electrode, the dielectric cap layer having a lower dielectric constant than the high-K gate dielectric layer, and source and drain contacts coupled to the source and drain regions.
    Type: Grant
    Filed: November 5, 2012
    Date of Patent: December 9, 2014
    Assignee: STMicroelectronics, Inc.
    Inventor: John H Zhang