Patent application number | Description | Published |
20090303482 | Enhanced Ovl dummy field enabling "on-the-fly" ovl measurement methods - A semiconductor wafer may include a dummy field configured to enable overlay measurements. The enhanced dummy field may include a plurality of encoding blocs that enable OVL measurements to be made throughout the enhanced dummy field. | 12-10-2009 |
20100155968 | Overlay Metrology Target - In one embodiment, a metrology target for determining a relative shift between two or more successive layers of a substrate may comprise; an first structure on a first layer of a substrate and an second structure on a successive layer to the first layer of the substrate arranged to determine relative shifts in alignment in both the x and y directions of the substrate by analyzing the first structure and second structure overlay. | 06-24-2010 |
20130163852 | ROTATIONAL MULTI-LAYER OVERLAY MARKS, APPARATUS, AND METHODS - In one embodiment, a semiconductor target for determining overlay error, if any, between two or more successive layers of a substrate or between two or more separately generated patterns on a single layer of a substrate is disclosed. The target comprises at least a plurality of first structures that are invariant for a plurality of first rotation angles with respect to a first center of symmetry (COS) of the first structures and a plurality of second structures that are invariant for a plurality of second rotation angles with respect to a second COS of the second structures. The first rotation angles differ from the second rotation angles, and first structures and second structures are formed on different layers of the substrate or separately generated patterns on a same layer of the substrate. | 06-27-2013 |
20140146322 | Apodization for Pupil Imaging Scatterometry - The disclosure is directed to various apodization schemes for pupil imaging scatterometry. In some embodiments, the system includes an apodizer disposed within a pupil plane of the illumination path. In some embodiments, the system further includes an illumination scanner configured to scan a surface of the sample with at least a portion of apodized illumination. In some embodiments, the system includes an apodized pupil configured to provide a quadrupole illumination function. In some embodiments, the system further includes an apodized collection field stop. The various embodiments described herein may be combined to achieve certain advantages. | 05-29-2014 |
Patent application number | Description | Published |
20090051917 | APPARATUS AND METHODS FOR DETERMINING OVERLAY OF STRUCTURES HAVING ROTATIONAL OR MIRROR SYMMETRY - Disclosed are overlay targets having flexible symmetry characteristics and metrology techniques for measuring the overlay error between two or more successive layers of such targets. In one embodiment, a target includes structures for measuring overlay error (or a shift) in both the x and y direction, wherein the x structures have a different center of symmetry (COS) than the y structures. In another embodiment, one of the x and y structures is invariant with a 180° rotation and the other one of the x and y structures has a mirror symmetry. In one aspect, the x and y structures together are variant with a 180° rotation. In yet another example, a target for measuring overlay in the x and/or y direction includes structures on a first layer having a 180 symmetry and structures on a second layer having mirror symmetry. In another embodiment, a target for determining overlay in the x and/or y direction includes structures on a first layer and structures on a second layer, wherein the structures on the first layer have a COS that is offset by a known amount from the COS of the structures on the second layer. In a specific implementation, any of the disclosed target embodiments may take the form of device structures. In a use case, device structures that have an inherent 180° rotational symmetry or a mirror symmetry in each of the first and second layers are used to measure overlay in a first layer and a second layer. Techniques for imaging targets with flexible symmetry characteristics and analyzing the acquired images to determine overlay or alignment error are disclosed. | 02-26-2009 |
20090291513 | OVERLAY MARKS, METHODS OF OVERLAY MARK DESIGN AND METHODS OF OVERLAY MEASUREMENTS - An overlay mark for determining the relative shift between two or more successive layers of a substrate and methods for using such overlay mark are disclosed. In one embodiment, the overlay mark includes at least one test pattern for determining the relative shift between a first and a second layer of the substrate in a first direction. The test pattern includes a first set of working zones and a second set of working zones. The first set of working zones are disposed on a first layer of the substrate and have at least two working zones diagonally opposed and spatially offset relative to one another. The second set of working zones are disposed on a second layer of the substrate and have at least two working zones diagonally opposed and spatially offset relative to one another. The first set of working zones are generally angled relative to the second set of working zones thus forming an “X” shaped test pattern. | 11-26-2009 |
20100005442 | Apparatus and Methods for Determining Overlay and Uses of Same - Disclosed are techniques and apparatus are provided for determining overlay error or pattern placement error (PPE) across the field of a scanner which is used to pattern a sample, such as a semiconductor wafer or device. This determination is performed in-line on the product wafer or device. That is, the targets on which overlay or PPE measurements are performed are provided on the product wafer or device itself. The targets are either distributed across the field by placing the targets within the active area or by distributing the targets along the streets (the strips or scribe areas) which are between the dies of a field. The resulting overlay or PPE that is obtained from targets distributed across the field may then be used in a number of ways to improve the fabrication process for producing the sample. For instance, the resulting overlay or PPE may be used to more accurately predict device performance and yield, more accurately correct a deviating photolithography scanning tool, or determine wafer lot disposition. | 01-07-2010 |
20100091284 | APPARATUS AND METHODS FOR DETECTING OVERLAY ERRORS USING SCATTEROMETRY - Disclosed are techniques, apparatus, and targets for determining overlay error between two layers of a sample. A plurality of targets is provided. Each target includes a portion of the first and second structures and each is designed to have an offset between its first and second structure portions. The targets are illuminated with electromagnetic radiation to thereby obtain spectra from each target at a −1 | 04-15-2010 |
20120153281 | APPARATUS AND METHODS FOR DETERMINING OVERLAY OF STRUCTURES HAVING ROTATIONAL OR MIRROR SYMMETRY - A semiconductor target for determining a relative shift between two or more successive layers of a substrate is provided. The target comprises a plurality of first structures formed in a first layer, and the first structures have a first center of symmetry (COS). The target further comprises a plurality of second structures formed in a second layer, and the second structures have second COS. The difference between the first COS and the second COS corresponds to an overlay error between the first and second layer and wherein the first and second structures have a 180° rotational symmetry, without having a 90° rotational symmetry, with respect to the first and second COS, respectively. | 06-21-2012 |