Zarlink Semiconductor Limited

X-fab Semiconductor Foundries Ag

Mitel Semiconductor Limited

Brian Martin

John Shannon

John Perring

Ian G Daniels

Christine Wallace

A method is provided for performing photolithography on a substrate which has a first region on a lower level and a second region on an upper level, wherein a first pattern area exists within said first region, a second pattern area exists within said second region, and at least said first and second regions are coated with a photoresist, the method comprising: a) exposing the photoresist through a first mask so as to expose said first region including said first pattern area, and thus create a first pattern in said first pattern area, but not expose said second pattern area; and b) exposing the photoresist through a second mask so as to expose said second pattern area, and thus create a second pattern in said second pattern area, but not expose said first pattern area, and also to expose an area of said first region which lies adjacent said second region.

Multiple level photolithography

A reticle for use in a photolithography process for exposing a photoresist layer in the production of a component which is formed from a plurality of adjacent exposed areas. The reticle includes an exposure aperture adapted to allow light to pass through the reticle, a patterned area within the exposure aperture which defines at least part of the functional design of the component, and one or more 'stitching' structures located close to one or more of the edges of the exposure aperture. The 'stitching' structures are arranged to create &#x201c;stitching&#x201d; marks on the photoresist, which can be used to determine whether the adjacent exposed areas have been accurately positioned.

Exposure positioning in photolithography

A method is provided for performing photolithography on a substrate which has a first region on a lower level and a second region on an upper level, wherein a first pattern area exists within said first region, a second pattern area exists within said second region, and at least said first and second regions are coated with a photoresist, the method comprising:

A method of carrying out optical proximity correction in the design of a reticle for exposing a photoresist of a wafer in photolithography using a lens having a focal plane, the method including generating a dense-isolated offset focus/exposure matrix, containing dense-isolated offset values, being the difference between values of linewidth for dense and isolated lines, as a function of focal plane position, for each of a plurality of different exposures, selecting from among the contours of the dense-isolated offset focus/exposure matrix for each different exposure, the flattest contour, and carrying out optical proximity correction on the basis that the exposure will be the exposure corresponding to said flattest contour.

Optical proximity correction method

A method of manufacturing integrated circuits is performed by coating a substrate with resist, exposing the resist to light through a pattern in a mask so as to define slots in the resist corresponding to the pattern in the mask, chemically developing the resist after exposure to light, and choosing the thickness of the resist so as to achieve the desired profile of the slots defined in the resist.

Growing community of inventors

Plymouth, United Kingdom

Brian Martin