Method for Generating Structures Smaller Than Normal Resolution Limit
Original Publication Date: 1989-Aug-01
Included in the Prior Art Database: 2005-Jan-28
By means of double exposure of photoresist (PR), a first exposure being to an image of photo-limited size and a second to the same image after displacement, a photoresist image is formed which is smaller than normal, single exposure photo resolution permits. Image displacement may be accomplished by standard laser interferometer stage motion control. An image may also be displaced with high precision by rotating a planar refracting element placed in the optical path of a projection exposure system. The technique permits elements to be constructed having smaller than standard resolution-limited dimensions for benefits other than device density, e.g., semiconductor device performance.