Patents by Inventor Balasubramanian Ramachandran

Balasubramanian Ramachandran 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).

  • Patent number: 7112763
    Abstract: A rapid thermal processing (RTP) system including a transmission pyrometer monitoring the temperature dependent absorption of the silicon wafer for radiation from the RTP lamps at a reduced power level. A look-up table is created relating unnormalized values of photodetector photocurrents with wafer and radiant lamp temperatures. A calibrating step measures the photocurrent with known wafer and lamp temperatures and all photocurrents measured thereafter are accordingly normalized. The transmission pyrometer may be used for closed loop control for thermal treatments below 500° C. or used in the pre-heating phase for a higher temperature process including radiation pyrometry in closed loop control. The pre-heating temperature ramp rate may be controlled by measuring the initial ramp rate and readjusting the lamp power accordingly. Radiation and transmission pyrometers may be included in an integrated structure with a beam splitter dividing radiation from the wafer.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: September 26, 2006
    Assignee: Applied Materials, Inc.
    Inventors: Aaron Hunter, Rajesh S. Ramanujam, Balasubramanian Ramachandran, Corina Elena Tanasa, Tarpan Dixit
  • Publication number: 20060160564
    Abstract: A multi-band communication device configured with a mobile communication device for voice or data communication over a cellular, satellite or other communication network and configured with an auxiliary communication system configured to receive and/or transmit an auxiliary communication signal. The mobile communication device and auxiliary communication system are integrated into the same components within the multi-band communication device thereby allowing the components to share the processing tasks associated with each communication device within the multi-band communication device. The auxiliary communication device may be configured to operate during standby mode of the mobile communication device, such as during reception of a paging signal. The auxiliary communication device may comprise, but is not limited to, AM or FM radio, personal communication devices such as FRS, GMRS, or weather band radio.
    Type: Application
    Filed: January 20, 2005
    Publication date: July 20, 2006
    Inventors: Norman Beamish, Darioush Agahi, Balasubramanian Ramachandran
  • Publication number: 20060086713
    Abstract: A rapid thermal processing (RTP) system including a transmission pyrometer monitoring the temperature dependent absorption of the silicon wafer for radiation from the RTP lamps at a reduced power level. A look-up table is created relating unnormalized values of photodetector photocurrents with wafer and radiant lamp temperatures. A calibrating step measures the photocurrent with known wafer and lamp temperatures and all photocurrents measured thereafter are accordingly normalized. The transmission pyrometer may be used for closed loop control for thermal treatments below 500° C. or used in the pre-heating phase for a higher temperature process including radiation pyrometry in closed loop control. The pre-heating temperature ramp rate may be controlled by measuring the initial ramp rate and readjusting the lamp power accordingly. Radiation and transmission pyrometers may be included in an integrated structure with a beam splitter dividing radiation from the wafer.
    Type: Application
    Filed: October 26, 2004
    Publication date: April 27, 2006
    Inventors: Aaron Hunter, Rajesh Ramanujam, Balasubramanian Ramachandran, Cornia Tanasa, Tarpan Dixit
  • Publication number: 20060068749
    Abstract: A low noise filter is arranged to receive an input signal from a downconverter. The low noise filter is constructed to block or cancel any DC offset in the input signal, as well as filter selected frequency components from the input signal. The low noise filter uses a shared capacitor both to handle the DC offset and to set filter response characteristics. As the low noise filter is implemented with a Frequency Dependent Negative Resistance (FDNR) device, the shared capacitor may be relatively small. The low noise filter has a load capacitor, with the output of the load capacitor coupled to a bias resistor and voltage. This bias structure cooperates with the load capacitor to set a high cutoff frequency for the low noise filter useful for blocking or canceling the DC offset.
    Type: Application
    Filed: September 25, 2004
    Publication date: March 30, 2006
    Inventors: Aly Ismail, John Vasa, Balasubramanian Ramachandran
  • Publication number: 20050254804
    Abstract: During fabrication, a rotating semiconductor substrate is radiated in accordance with a thermal recipe. Temperature measurements of the semiconductor substrate are obtained along with the position of the semiconductor substrate at the time of each temperature measurement. It is then determined for the position of the semiconductor substrate whether at least one particular temperature measurement of the temperature measurements should be filtered. If so, at least one filtered temperature measurement is obtained. The radiation of the semiconductor substrate is subsequently controlled based on the temperature measurements, the at least one filtered temperature measurement, and the thermal recipe.
    Type: Application
    Filed: April 11, 2005
    Publication date: November 17, 2005
    Applicant: Applied Materials, Inc.
    Inventors: Wolfgang Aderhold, Balasubramanian Ramachandran, Leonid Tertitski, Patrick Stone
  • Patent number: 6897131
    Abstract: Lamp based spike annealing was improved to address the aggressive requirements of <100 nm Ultra Shallow Junction (USJ) technologies. Improvements focused on enhancing cool down rates, and thereby improving spike sharpness. Boron ion implanted substrates with varying ion-implanted energy and dose were then annealed to characterize the improvements in spike annealing. A greater than 10% improvement in sheet resistance and junction depth was realized on substrates that were annealed with the improved spike profile. The improved spike anneal had the same comparable uniformity to the standard spike anneal.
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: May 24, 2005
    Assignee: Applied Materials, Inc.
    Inventors: Balasubramanian Ramachandran, Ravi Jallepally, Ryan C. Boas, Sundar Ramamurthy, Amir Al-Bayati, Houda Graoui, Joseph M. Spear
  • Publication number: 20050102108
    Abstract: Method and apparatus for obtaining a tailored heat transfer profile in a chamber housing a microprocessor manufacturing process, including estimating heat transfer properties of the chamber; estimating heat absorptive properties of a wafer; adjusting the physical characteristics of the chamber to correct the heat transfer properties; and utilizing the chamber for manufacturing microprocessors.
    Type: Application
    Filed: September 24, 2004
    Publication date: May 12, 2005
    Inventors: Balasubramanian Ramachandran, Joseph Ranish, Ravi Jallepally, Sundar Ramamurthy, Raman Achutharaman, Brian Haas, Aaron Hunter
  • Patent number: 6888104
    Abstract: A substrate support ring has a band having an inner perimeter that at least partially surrounds a periphery of the substrate. The band has a radiation absorption surface. A lip extends radially inwardly from the inner perimeter of the band to support the substrate. The band and lip can be formed from silicon carbide, and the radiation absorption surface can be an oxidized layer of silicon carbide. In one version, the band and lip have a combined thermal mass Tm, and the radiation absorption surface has an absorptivity A and a surface area Sa, such that the ratio (A×Sa)/Tm is from about 4×10?5 m2K/J to about 9×10?4 m2K/J.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: May 3, 2005
    Assignee: Applied Materials, Inc.
    Inventors: Joseph M. Ranish, Aaron Muir Hunter, Balasubramanian Ramachandran, Jallepally Ravi, Sundar Ramamurthy, Vedapuram S. Achutharaman, Khurshed Sorabji
  • Publication number: 20040185807
    Abstract: A dynamically varying linearity system “DVLS” capable of varying the linearity of a radio frequency (RF) front-end of a communication device responsive to receiving a condition signal indicating a desired mode of operation of a transmitter. The DVLS may include a condition signal indicative of the desired mode of operation and a controller that adjusts the linearity of the transmitter responsive to the condition signal. The condition signal may be responsive to a user interface. The controller, responsive to the condition signal, may dynamically adjust the operating current of the transmitter.
    Type: Application
    Filed: October 27, 2003
    Publication date: September 23, 2004
    Inventor: Balasubramanian Ramachandran
  • Publication number: 20040126999
    Abstract: Lamp based spike annealing was improved to address the aggressive requirements of <100 nm Ultra Shallow Junction (USJ) technologies. Improvements focused on enhancing cool down rates, and thereby improving spike sharpness. Boron ion implanted substrates with varying ion-implanted energy and dose were then annealed to characterize the improvements in spike annealing. A greater than 10% improvement in sheet resistance and junction depth was realized on substrates that were annealed with the improved spike profile. The improved spike anneal had the same comparable uniformity to the standard spike anneal.
    Type: Application
    Filed: September 22, 2003
    Publication date: July 1, 2004
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Balasubramanian Ramachandran, Ravi Jallepally, Ryan C. Boas, Sundar Ramamurthy, Amir Al-Bayati, Houda Graoui, Joseph M. Spear
  • Publication number: 20040052512
    Abstract: During fabrication, a rotating semiconductor substrate is radiated in accordance with a thermal recipe. Temperature measurements of the semiconductor substrate are obtained along with the position of the semiconductor substrate at the time of each temperature measurement. It is then determined for the position of the semiconductor substrate whether at least one particular temperature measurement of the temperature measurements should be filtered. If so, at least one filtered temperature measurement is obtained. The radiation of the semiconductor substrate is subsequently controlled based on the temperature measurements, the at least one filtered temperature measurement, and the thermal recipe.
    Type: Application
    Filed: September 12, 2002
    Publication date: March 18, 2004
    Applicant: Applied Materials, Inc.
    Inventors: Wolfgang R. Aderhold, Balasubramanian Ramachandran, Leonid M. Tertitski, Patrick F. Stone
  • Patent number: 6674999
    Abstract: A dynamically varying linearity system “DVLS” capable of varying the linearity of a radio frequency (RF) front-end of a communication device responsive to receiving a condition signal indicating a desired mode of operation of a transmitter. The DVLS may include a condition signal indicative of the desired mode of operation and a controller that adjusts the linearity of the transmitter responsive to the condition signal. The condition signal may be responsive to a user interface. The controller, responsive to the condition signal, may dynamically adjust the operating current of the transmitter.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: January 6, 2004
    Assignee: Skyworks Solutions, Inc
    Inventor: Balasubramanian Ramachandran
  • Patent number: 6560446
    Abstract: A dynamically varying linearity system “DVLS” capable of varying the linearity of a radio frequency (RF) front-end of a communication device responsive to receiving a condition signal indicating a desired mode of operation of a transmitter. The DVLS may include a condition signal indicative of the desired mode of operation and a controller that adjusts the linearity of the transmitter responsive to the condition signal. The condition signal may be responsive to a user interface. The controller, responsive to the condition signal, may dynamically adjust the operating current of the transmitter.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: May 6, 2003
    Assignee: Skyworks Solutions, Inc.
    Inventor: Balasubramanian Ramachandran
  • Publication number: 20020159503
    Abstract: A dynamically varying linearity system “DVLS” capable of varying the linearity of a radio frequency (RF) front-end of a communication device responsive to receiving a condition signal indicating a desired mode of operation of a transmitter. The DVLS may include a condition signal indicative of the desired mode of operation and a controller that adjusts the linearity of the transmitter responsive to the condition signal. The condition signal may be responsive to a user interface. The controller, responsive to the condition signal, may dynamically adjust the operating current of the transmitter.
    Type: Application
    Filed: March 16, 2001
    Publication date: October 31, 2002
    Applicant: Conexant Systems, Inc.
    Inventor: Balasubramanian Ramachandran
  • Publication number: 20020119763
    Abstract: A system capable of varying the operating current of at least one frequency source in the receiver of a communication device in response to the presence of an undesired signal within a frequency band of signals received at the receiver. The system may include a condition signal indicative of the presence of an undesired signal within a frequency band of signals received at a receiver and a controller that adjusts a frequency source responsive to the condition signal.
    Type: Application
    Filed: February 26, 2001
    Publication date: August 29, 2002
    Inventors: Balasubramanian Ramachandran, Aravind Loke, Trevor Robinson