Patents by Inventor Avijit Ray-Chaudhuri

Avijit Ray-Chaudhuri 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).

  • Diffractive element in extreme-UV lithography condenser
    Patent number: 6285497
    Abstract: Condensers having a mirror with a diffraction grating in projection lithography using extreme ultra-violet significantly enhances critical dimension control. The diffraction grating has the effect of smoothing the illumination at the camera's entrance pupil with minimum light loss. Modeling suggests that critical dimension control for 100 nm features can be improved from 3 nm to less than about 0.5 nm.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: September 4, 2001
    Assignee: EUV LLC
    Inventors: William C. Sweatt, Avijit Ray-Chaudhuri