Infineon Technologies Ag

Michael Heissmeier

Molela Moukara

Burkhard Ludwig

Christoph N&ouml;lscher

Markus Hofs&auml;ss

Rainer Pforr

Uwe Griesinger

Christoph Friedrich

A photoresist layer on a substrate wafer is exposed in first sections with a first exposure radiation and in second sections with a second exposure radiation that is phase-shifted by 180&deg;. The first and second sections adjoin one another in boundary regions in which the photoresist layer is artificially not sufficiently exposed. Where a distance between these boundary regions is smaller than a photolithographically critical, least distance, the photoresist layer is exposed, at a first boundary region, with a third exposure radiation and at a second boundary region with a fourth exposure radiation phase-shifted by 180&deg;. A trim mask provided for the process has a first translucent region and a second translucent region. The first light-transparent region and the second light-transparent region are fashioned such that the light passing through the first light-transparent region and the light passing through the second light-transparent region has a phase displacement of 180&deg;.

Method for determining and removing phase conflicts on alternating phase masks

An alternating phase mask is described in which a propagation of a T phase conflict which occurs in the case of a T pattern structure is avoided by producing a phase jump at one of the 90&deg; corners of the T pattern structure. First and second transparent area segments, which produce a mutual phase difference of 180&deg;, are separated by a narrow slot running approximately at 45&deg; toward the corner of the T pattern structure. The structure containing the transparent area segments, which are separated by the slot running at 45&deg;, can also be provided at the other corner of the T structure providing a solution for each T conflict. The trimming mask for eliminating the dark line artificially produced by the 180&deg; phase jump is a conventional mask and requires no additional coloration. Moreover, alignment errors are minimal on account of the small number of trimming openings.

Alternating phase mask

An alternating phase mask having a branched structure containing two opaque segments is described. Two transparent surface segments are disposed on both sides of the segments or the components thereof, respectively. The surface segments are provided with phases that are displaced by 180&deg;&plusmn;&Dgr; &agr;, whereby &Dgr; &agr; a is not more than 25&deg;. The surface segments are separated by at least one transparent surface boundary segment whose phase is situated between the phases of the adjacent surface segments.

Growing community of inventors

München, Germany

Michael Heissmeier