Patents by Inventor Bas M. Mertens

Bas M. Mertens 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).

  • Device, EUV lithographic device and method for preventing and cleaning contamination on optical elements
    Patent number: 7462842
    Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: December 9, 2008
    Assignee: Carl Zeiss SMT AG
    Inventors: Marco E. Wedowski, Frank Stietz, Bas M. Mertens, Roman Klein
  • Device, EUV-lithographic device and method for preventing and cleaning contamination on optical elements
    Patent number: 7060993
    Abstract: The invention relates to a method for preventing contamination on the surfaces of optical elements comprising a multi-layer system, during the exposure thereof to radiation at signal wave lengths in an evacuated closed system comprising a residual gas atmosphere, whereby the photocurrent generated by means of photo emission from the radiated surface of the multi-layer system is measured. The photocurrent is used to regulate the gas composition of the residual gas. The gas composition is altered according to at least one lower and one upper threshold value of the photocurrent. The invention also relates to a device for regulating the contamination on the surface of at least one optical element during exposure and an EUV-lithographic device and a method for cleaning the surfaces of the optical elements contaminated by carbon.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: June 13, 2006
    Assignee: Carl Zeiss SMT AG
    Inventors: Marco E. Wedowski, Frank Stietz, Bas M. Mertens, Roman Klein