Nxp B.v.

Anja Vanleenhove

David Van Steenwinckel

Gerben Doornbos

Mark Van Dal

Peter Dirksen

Peter Zandbergen

Casper Juffermans

Hans Kwinten

The invention relates to a method of photolithography comprising the steps of: providing a substrate and forming a layer of a photoresist on the substrate, performing a first exposure in which a predetermined part of the layer of photoresist is irradiated through a mask having a pattern for forming a latent image of said pattern in the layer of the photoresist, performing a pretreatment on the layer of the photoresist to remove a predetermined part of the latent image before performing the fixation. The method provides an improved process window. The invention further relates to a photoresist for use within the method of the invention.

Photolithography

A method of forming a pattern in at least one device layer in or on a substrate comprises: coating the device layer with a first photoresist layer; exposing the first photoresist using a first mask; developing the first photoresist layer to form a first pattern on the substrate; coating the substrate with a protection layer; treating the protection layer to cause a change therein where it is in contact with the first photoresist, to render the changed protection layer substantially immune to a subsequent exposure and/or developing step; coating the substrate with a second photoresist layer; exposing the second photoresist layer using a second mask; and developing the second photoresist layer to form a second pattern on the substrate without significantly affecting the first pattern in the first photoresist layer, wherein the first and second patterns together define interspersed features having a spatial frequency greater than that of the features defined in each of the first and second patterns separately. The process has particular utility in defining source, drain and fin features of finFET devices with a smaller feature size than otherwise achievable with the prevailing lithography tools.

Double patterning for lithography to increase feature spatial density

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Kessel-lo, Belgium

Anja Vanleenhove