Patents by Inventor Raj Mohindra

Raj Mohindra 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: 5651379
    Abstract: The invention relates to a wafer rinsing system for rinsing chemicals and particles off of wafers without introducing contaminants. The system reduces the particle count on wafers by filtering the water and the gas used during rinsing at the wet bench. The system includes a rinsing unit, a local water filter bank, a local gas filtering system, an H.sub.2 O.sub.2 injection unit, an auxiliary chemical injection unit, and a controller for operating the other components. The water filter bank provides a multiple stage filtering system to eliminate particles without a substantial drop in water pressure. The H.sub.2 O.sub.2 injection unit provides a local source of H.sub.2 O.sub.2 to clean the filter and rinser and to provide a mechanism for controlling the formation of native oxide on the wafer during rinsing. The auxiliary chemical injection unit provides a chemical additive to the rinsing unit to enhance the wafer cleaning process.
    Type: Grant
    Filed: December 1, 1995
    Date of Patent: July 29, 1997
    Assignee: YieldUP International
    Inventors: Raj Mohindra, Abhay K. Bhushan, Rajiv Bhushan, Suraj Puri
  • Patent number: 5634978
    Abstract: A method operates a system for wet processing of semiconductors. The system includes an inlet coupled to a fluid source, and a filter coupled to the inlet. The system also includes a sealed vessel coupled to the filter where the sealed vessel has a lower liquid portion and an upper vapor portion. The system further includes an outlet coupled to the sealed vessel. The outlet is attached to the lower liquid portion. A solvent injector coupled to the sealed vessel is also used. The solvent injector is coupled to the upper vapor portion, and supplies a gaseous mixture including a polar organic compound. The polar organic compound is a non-saturated polar organic vapor. The system also includes a gas source coupled to the sealed vessel. The gas source is coupled to the upper vapor portion, and supplies an inert gas into the upper vapor portion. A device for removing the liquid from the lower liquid portion at substantially a constant liquid level rate is also included.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: June 3, 1997
    Assignee: YieldUP International
    Inventors: Raj Mohindra, Abhay Bhushan, Rajiv Bhushan, Suraj Puri, John H. Anderson, Sr., Jeffrey Nowell
  • Patent number: 5571337
    Abstract: A method for drying articles with flat surfaces such as a semiconductor wafer. The method includes steps of immersing a semiconductor wafer in a liquid such as water, and displacing the liquid with a gaseous mixture. The liquid is displaced adjacent to a face of the wafer as measured from the face. A step of pulsing drying fluid directed at wafer edges is also included. The method dries wafers without the use of any harmful organic solvents and the like, and also dries wafers without substantial movement.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: November 5, 1996
    Assignee: YieldUP International
    Inventors: Raj Mohindra, Abhay Bhushan, Rajiv Bhushan, Suraj Puri, John H. Anderson, Jeffrey Nowell
  • Patent number: 5542441
    Abstract: The invention relates to a wafer rinsing system for rinsing chemicals and particles off of wafers without introducing contaminants. The system reduces the particle count on wafers by filtering the water and the gas used during rinsing at the wet bench. The system includes a rinsing unit, a local water filter bank, a local gas filtering system, an H.sub.2 O.sub.2 injection unit, an auxiliary chemical injection unit, and a controller for operating the other components. The water filter bank provides a multiple stage filtering system to eliminate particles without a substantial drop in water pressure. The H.sub.2 O.sub.2 injection unit provides a local source of H.sub.2 O.sub.2 to clean the filter and rinser and to provide a mechanism for controlling the formation of native oxide on the wafer during rinsing. The auxiliary chemical injection unit provides a chemical additive to the rinsing unit to enhance the wafer cleaning process.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: August 6, 1996
    Assignee: YieldUP International
    Inventors: Raj Mohindra, Abhay K. Bhushan, Rajiv Bhushan, Suraj Puri