Intel Corporation

Joseph C Langston

Pei-yang Yan

Giang T Dao

Guojing Zhang

Patrick M Troccolo

A photolithography method for creating very small line dimensions includes making a mask by exposing a mask blank through a reticle in a reduction photolithography exposure tool, at a reduction of N. The fabricated mask is then placed in a second photolithography exposure tool at a second reduction M, to expose a wafer substrate at a reduction of M. The resulting patterned substrate will have a critical dimension equaling the critical dimension of the original reticle, divided by the factor N times M. In this manner, very small size patterns can be created even though a larger pattern starting reticle is used.

Multiple reduction photolithography technique

A silicon-substrate based reflective photolithographic mask fabrication technique is described. The process begins with a multilayer, resonant reflecting substrate. A thin layer of silicon dioxide or other material capable of acting as an etch stop layer is deposited thereon. Then, a transmissive layer is deposited on the thin layer of etch stop layer. The transmissive layer is substantially transmissive to the wavelength of light used in the photolithography as well as capable of being selectively etched relative to the underlying etch stop layer. Then, the transmissive layer is etched to open preselected, absorptive areas. An absorptive layer is then deposited thereon. The absorptive layer is substantially absorptive to the wavelength of light used as well as capable of completely filling the opened areas of the transmissive layer. The absorptive layer is then planarized, and a thin protective cap is deposited thereon.

Using thin films as etch stop in EUV mask fabrication process

A new process and an improved process for fabricating device layers with ultrafine features. In one embodiment a device layer to be patterned is deposited above a substrate and a photoresist layer is deposited above that device layer. A reticle having a first transparent layer and a second opaque layer is used to pattern the photoresist layer. The reticle includes a first region with a first phase and a second region with a second phase such that the incident radiation is shifted when passing through the reticle. The second reticle layer is disposed above the first reticle layer and proximate to the location where the first region transitions to the second region of the first reticle layer. A stepper is used to expose the photoresist to radiation through the reticle. The critical dimensions of the device layer being patterned are controlled by adjusting the partial coherence of the stepper during exposure.

Processes for fabricating device layers with ultrafine features

A method of forming a patterned resist layer on a semiconductor substrate is described. The substrate is coated with a resist layer and placed on a substrate stage within a projection printer. The projection printer includes a radiation source that emits a radiation wave having a predetermined wavelength, a lens having a predetermined numerical aperture, and a reticle having an opaque section and a transparent section. The projection printer has a resolution that is a function of the wavelength and the numerical aperture. The resist layer is exposed to a radiation pattern formed at the surface of the resist layer when the radiation wave passes through the reticle. The radiation pattern includes a radiative area lying beneath the transparent section and a substantially radiation-free area lying beneath the opaque section. All dimensions of the radiation pattern at the surface of the resist layer are no less than the resolution. A portion of the substantially radiation-free area prevents a significant amount radiation from reaching a first region in the resist layer during all of the exposure. The first region has a pair of opposite edges. Spaced-apart second regions in the resist layer are exposed by the radiative area during the exposure. A resist pattern is formed where a second region lies immediately adjacent to the first region at an opposite edge and another second region lies immediately adjacent to the first region at the other opposite edge. The opposite edges are formed at different times and the distance between the opposite edges are less than the resolution.

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Los Altos, CA, United States of America

Joseph C Langston