Globalfoundries Inc.

Globalfoundries Singapore Pte. Ltd.

Arthur Hotzel

Paul Willard Ackmann

Soon Yoeng Tan

Guo Xiang Ning

Remi Riviere

Wolfram Grundke

Matthias Ruhm

Eric Cotte

Philipp Jaschinsky

Torsten Maehr

Martin Freitag

A method and apparatus for detecting changes in the vibrational mode spectra and/or elasticity of a pellicle without reliance upon visual inspection are provided. Embodiments include providing a pellicle, a lower surface of the pellicle attached to a photomask; directing light from a light source onto an upper surface of the pellicle at an angle to the upper surface; causing a deflection of the pellicle concurrently with the light being directed onto the pellicle; detecting light reflected off of the deflected pellicle; and characterizing a vibrational mode of the pellicle based on the detection.

In-situ contactless monitoring of photomask pellicle degradation

Methods for reducing reticle transmission differences and for optimizing layer placement for overlay in MTRs and CTRs are disclosed. Embodiments include providing a reticle having a prime area and a frame area surrounding the prime area; determining RT differences across the prime area; and providing RT adjustment structures on the reticle to decrease the RT differences. Other embodiments include grouping multiple layers of a semiconductor production flow, the layers for each group having an RT difference less than a predetermined value; and placing the layers on plural ordered reticles of a reticle set, each reticle having multiple image fields, by selecting, for each reticle, layers from a single group and optimizing placement of the layers for overlay. Other embodiments include selectively rotating image fields on a reticle having multiple image fields to improve overlay, or optimizing placement of DDLs on CTRs by placing each design orientation on a different reticle.

Cross technology reticle (CTR) or multi-layer reticle (MLR) CDU, registration, and overlay techniques

Methods, apparatus, and system for minimizing defectivity in top-coat-free immersion photolithography are provided. Embodiments include forming a photomask by defining a first pattern including a main functional pattern in the photomask; and defining a second pattern including a sub-resolution fill pattern in the photomask in areas between or and/or within structures of the first pattern, the fill pattern having a pitch or range of pitches smaller than a minimum resolved pitch of the lithographic exposure and/or at least a part of the sub-resolution structures of the sub-resolution fill pattern not substantially modifying an imaging of any structure of the main functional pattern in the lithographic exposure.

Methods, apparatus, and systems for minimizing defectivity in top-coat-free lithography and improving reticle CD uniformity

A method includes performing a spin coating process. In the spin coating process, a first fluid is dispensed to a surface of a wafer. The method further includes performing an inspection of an edge area of the wafer. On the basis of the inspection of the edge area of the wafer, a defect analysis is performed. In the defect analysis, it is determined if the edge area of the wafer has a defect that is indicative of an insufficient coating of the surface of the wafer by the first fluid.

Methods including a processing of wafers and spin coating tool

Asymmetric heating and/or thermal expansion of a reticle or an image field is reduced. Embodiments include exposing a wafer with an actual image field (including a pattern for a chip layer) on a multilayer reticle, and performing a dummy exposure with another image field of the reticle. Other embodiments include exposing a wafer with a reticle area including both the actual and one or more other image fields of a multilayer reticle, sacrificing any die on the wafer that is exposed with substantial illumination with an image field other than the actual image field. Further embodiments include dummy exposures or enlargement of the illuminated reticle area of a single layer reticle with variation in pattern density between regions of the image field. Further embodiments include changing the image field geometry of a multilayer or single layer reticle.

Asymmetric reticle heating of multilayer reticles eliminated by dummy exposures and related methods

Correction of reticle defects, including reticle weak spots or shortcomings, is accomplished with a second exposure. Embodiments include obtaining a reticle with a pattern corresponding to a wafer pattern design, exposing a wafer with the reticle, modifying the design, designating variations between the design and the modified design as reticle defects, and exposing the wafer with correction patterns containing structure corresponding to the modified design at defect positions. Other embodiments include modifying, eliminating, and/or shifting the pattern near a reticle blank defect position, and exposing a wafer with the reticle and with a correction pattern containing structure corresponding to the design at a defect position; modifying a patterned reticle surface layer near a defect forming an expanded defect, exposing a wafer with the modified reticle and with an expanded defect correction pattern; and exposing a wafer with a reticle and with a correction pattern larger than a detected reticle defect.

Reticle defect correction by second exposure

Correction of reticle defects, such as EUV reticle defects, is accomplished with a second exposure. Embodiments include obtaining a reticle with a first pattern corresponding to a design for a wafer pattern, detecting dark defects and/or design/OPC weak spots in the first pattern, exposing a resist covered wafer using the reticle, and exposing the wafer using a second reticle with a second pattern or a second image field with openings corresponding to the dark defects, with a repair pattern on the reticle or on another reticle, or with a programmed e-beam or laser writer.

A pellicle frame is mechanically attached to a reticle, without use of an adhesive. An embodiment includes mechanically attaching a pellicle frame to a front surface of a reticle, removing the pellicle frame from the reticle, cleaning the reticle, and mechanically reattaching the pellicle frame to the reticle. Embodiments further include using a clamp to mechanically attach the pellicle frame to the reticle. Embodiments further include forming the pellicle frame with a flange having an opening in the center, and forming the clamp with two portions, one portion with a protrusion that fittingly engages the opening in the flange and with a second opening, and the second portion with a segment that extends behind the reticle and with a second protrusion that fittingly engages the second opening.

Mechanical fixture of pellicle to lithographic photomask

Correction of CD variation is accomplished with a second exposure, e.g. using a second reticle. Embodiments include exposing a first wafer with a first dose using a first reflective reticle having a pattern corresponding to a wafer target pattern, or measuring and/or inspecting first reticle pattern portions and calculating and/or simulating corresponding first wafer pattern portions obtained with a predetermined first dosage, identifying CD variations between the exposed wafer or the calculated/simulated first wafer pattern and the target pattern for different target pattern features, exposing a second wafer with the first reticle using a second dose, and correcting the CD variations by applying an additional exposure of the second wafer, before or after exposing the second wafer with the first reticle. Embodiments further include using additional exposures to prevent printing unwanted structures on the reticle or to deliberately vary sizes of selected structures on the wafer for development purposes.

Lithographic CD correction by second exposure

Correction of critical dimension variation is accomplished with a second exposure, e.g. using a second reticle. Embodiments include exposing a first wafer with a first dose using a first reticle, having a pattern corresponding to a target pattern for a wafer, identifying CD variations between the exposed wafer and the target pattern for different features in the target pattern, exposing a second wafer with the first reticle using a second dose, less than or equal to the first dose, and correcting the CD variations by applying an additional exposure of the second wafer. Embodiments further include using one or more additional exposures to prevent printing unwanted structures on the reticle or to deliberately vary the sizes of selected structures on the wafer for development purposes.

A reticle is cleaned by vapor condensing on the active surface of the reticle. An embodiment includes positioning the reticle in a cleaning chamber having a bottom surface, with the active surface of the reticle facing the bottom surface of the cleaning chamber, and directing vapor at the active surface of the reticle. Embodiments further include filling a reservoir in a bottom portion of the cleaning chamber with liquid and directing vapor by heating the liquid. Embodiments further include cooling the reticle concurrently with heating the liquid. Embodiments further include rotating the reticle concurrently with heating the liquid and cooling the reticle. Embodiments further include emptying the reservoir and dry spinning the reticle, subsequent to cleaning the reticle.

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Dresden, Germany

Arthur Hotzel