公开(公告)号：US10579768B2

公开(公告)日：2020-03-03

申请号：US15502950

申请日：2016-11-04

Applicant: KLA-Tencor Corporation

Inventor： Vladimir Levinski ,  Eitan Hajaj ,  Tal Itzkovich ,  Sharon Aharon ,  Michael E. Adel ,  Yuri Paskover ,  Daria Negri ,  Yuval Lubashevsky ,  Amnon Manassen ,  Myungjun Lee ,  Mark D. Smith

IPC: G06F17/50 ,  H01L21/027 ,  G03F7/20

Abstract: Metrology targets and target design methods are provided, in which target elements are defined by replacing elements from a periodic pattern having a pitch p, by assist elements having at least one geometric difference from the replaced elements, to form a composite periodic structure that maintains the pitch p as a single pitch. Constructing targets within the bounds of compatibility with advanced multiple patterning techniques improves the fidelity of the targets and fill factor modulation enables adjustment of the targets to produce sufficient metrology sensitivity for extracting the overlay while achieving process compatibility of the targets.

公开(公告)号：US10444639B2

公开(公告)日：2019-10-15

申请号：US15843371

申请日：2017-12-15

Applicant: KLA-Tencor Corporation

Inventor： Onur Nihat Demirer ,  William Pierson ,  Mark D. Smith ,  Jeremy S. Nabeth ,  Miguel Garcia-Medina ,  Lipkong Yap

IPC: G03F7/20 ,  H01L21/027 ,  G03F9/00

Abstract: A process control system includes a controller configured to generate a reference overlay signature based on one or more overlay reference layers of a sample, extrapolate the reference overlay signature to a set of correctable fields for the exposure of a current layer of the sample to generate a full-field reference overlay signature, identify one or more alignment fields of the set of correctable fields, generate an alignment-correctable signature by modeling alignment corrections for the set of correctable fields, subtract the alignment-correctable signature from the full-field reference overlay signature to generate feedforward overlay corrections for the current layer when the one or more overlay reference layers are the same as the one or more alignment reference layers, generate lithography tool corrections based on the feedforward overlay corrections, and provide the lithography tool corrections for the current layer to the lithography tool.

公开(公告)号：US20180196358A1

公开(公告)日：2018-07-12

申请号：US15413628

申请日：2017-01-24

Applicant: KLA-Tencor Corporation

Inventor： Myungjun Lee ,  Stewart Robertson ,  Mark D. Smith ,  Pradeep Subrahmanyan

IPC: G03F7/20

CPC classification number: G03F7/70641 ,  G03F1/44 ,  G03F7/70091

Abstract: A lithography system includes an illumination source, one or more projection optical elements, and a pattern mask. The illumination source includes one or more illumination poles. The pattern mask includes a set of focus-sensitive mask elements periodically distributed with a pitch, wherein the set of focus-sensitive mask elements is configured to diffract illumination from the one or more illumination poles. The pitch is selected such that two diffraction orders of illumination associated with each of the one or more illumination poles are asymmetrically distributed in a pupil plane of the one or more projection optical elements. Further, the one or more projection optical elements are configured to expose a sample with an image of the set of focus-sensitive pattern mask elements based on the two diffraction orders of illumination associated with each of the one or more illumination poles. Additionally, one or more printing characteristics of the image of the set of focus-sensitive pattern mask elements on the sample is indicative of a position of the sample within a focal volume of the one or more projection optical elements.

公开(公告)号：US20180173839A1

公开(公告)日：2018-06-21

申请号：US15810898

申请日：2017-11-13

Applicant: KLA-Tencor Corporation

Inventor： Chao Fang ,  Mark D. Smith ,  Brian Duffy

IPC: G06F17/50 ,  G01B21/02 ,  G06T7/00 ,  G03F7/20

CPC classification number: G06F17/5081 ,  G01B21/02 ,  G03F7/705 ,  G03F7/70616 ,  G06F2217/82 ,  G06T7/0004 ,  G06T7/001 ,  G06T2200/04 ,  G06T2200/08 ,  G06T2207/20076 ,  G06T2207/20081 ,  G06T2207/30148

Abstract: A metrology system includes a controller communicatively coupled to a metrology tool. The controller may generate a three-dimensional model of a sample, generate a predicted metrology image corresponding to a predicted analysis of the sample with the metrology tool based on the three-dimensional model, evaluate two or more candidate metrology recipes for extracting the metrology measurement from the one or more predicted metrology images, select, based on one or more selection metrics, a metrology recipe from the two or more candidate metrology recipes for extracting a metrology measurement from an image of the structure from the metrology tool, receive an output metrology image of a fabricated structure from the metrology tool based on a metrology measurement of the fabricated structure, and extract the metrology measurement associated with the fabricated structure from the output metrology image based on the metrology recipe.

公开(公告)号：US10209627B2

公开(公告)日：2019-02-19

申请号：US15413628

申请日：2017-01-24

Applicant: KLA-Tencor Corporation

Inventor： Myungjun Lee ,  Stewart Robertson ,  Mark D. Smith ,  Pradeep Subrahmanyan

IPC: G03B27/52 ,  G03F7/20 ,  G03F1/44

Abstract: A lithography system includes an illumination source, projection optical elements, and a pattern mask. The illumination source includes one or more illumination poles. The pattern mask includes a set of focus-sensitive mask elements distributed with a pitch and, is configured to diffract illumination from the one or more illumination poles. The pitch may be selected such that two diffraction orders of illumination associated with each of the one or more illumination poles are asymmetrically distributed in a pupil plane of the projection optical elements. Further, the projection optical elements may expose a sample with an image of the set of focus-sensitive pattern mask elements based on the two diffraction orders of illumination associated with each of the one or more illumination poles such that one or more printing characteristics is indicative of a position of the sample within a focal volume of the projection optical elements.

公开(公告)号：US10095122B1

公开(公告)日：2018-10-09

申请号：US15289590

申请日：2016-10-10

Applicant: KLA-Tencor Corporation

Inventor： Myungjun Lee ,  Mark D. Smith

IPC: G03B27/42 ,  G03F7/20 ,  G03F1/76 ,  G03F1/44

Abstract: A lithography system includes an illumination source, a pattern mask, and an optical element configured to expose a sample with an image of the pattern mask for the fabrication of one or more printed device structures and one or more metrology target structures. The pattern mask includes a device pattern mask area and a metrology target pattern mask area. The device pattern mask area includes a set of device pattern elements distributed with a device pitch. The metrology target pattern mask area includes a set of metrology target pattern elements. The one or more printed metrology target structures include a set of metrology target elements distributed with a metrology target pitch. Regions of the metrology target pattern mask area include sub-resolution features having widths smaller than the resolution of the optical element such that the sub-resolution pattern elements are not included on the one or more printed metrology target structures.

公开(公告)号：US10030965B2

公开(公告)日：2018-07-24

申请号：US15148116

申请日：2016-05-06

Applicant: KLA-Tencor Corporation

Inventor： Stilian Ivanov Pandev ,  Sanjay Kapasi ,  Mark D. Smith ,  Ady Levy

IPC: G01B11/00 ,  H01L21/66

Abstract: Methods and systems for monitoring parameters characterizing a set of hot spot structures fabricated at different locations on a semiconductor wafer are presented herein. The hot spot structures are device structures that exhibit sensitivity to process variations and give rise to limitations on permissible process variations that must be enforced to prevent device failures and low yield. A trained hot spot measurement model is employed to receive measurement data generated by one or more metrology systems at one or more metrology targets and directly determine values of one or more hot spot parameters. The hot spot measurement model is trained to establish a functional relationship between one or more characteristics of a hot spot structure under consideration and corresponding measurement data associated with measurements of at least one metrology target on the same wafer. A fabrication process parameter is adjusted based on the value of a measured hot spot parameter.

公开(公告)号：US10018919B2

公开(公告)日：2018-07-10

申请号：US15224290

申请日：2016-07-29

Applicant: KLA-Tencor Corporation

Inventor： Myungjun Lee ,  Mark D. Smith

IPC: G03B27/54 ,  G03F7/20 ,  G03F1/22

CPC classification number: G03F7/70283 ,  G03F1/22 ,  G03F1/38 ,  G03F7/70091 ,  G03F7/70625 ,  G03F7/70633 ,  G03F7/70683

Abstract: A lithography system includes an illumination source including two illumination poles separated along a first direction and symmetrically distributed around an optical axis, a pattern mask to receive illumination from the illumination source, and a set of projection optics to generate an image corresponding to the pattern mask onto a sample. The pattern mask includes a metrology target pattern mask and device pattern mask elements. The device pattern mask elements are distributed along the first direction with a device separation distance. The metrology target pattern mask includes a set of metrology target pattern mask elements having a diffraction pattern corresponding to that of the device pattern mask elements. A metrology target generated on the sample associated with the metrology target pattern mask is characterizable along a second direction and has printing characteristics corresponding to those of device pattern elements generated on the sample associated with the device pattern mask elements.

公开(公告)号：US10007191B2

公开(公告)日：2018-06-26

申请号：US15232302

申请日：2016-08-09

Applicant: KLA-Tencor Corporation

Inventor： John J. Biafore ,  Mark D. Smith ,  John S. Graves ,  David A. Blankenship ,  Alessandro Vaglio Pret

IPC: G03B27/32 ,  G03C5/18 ,  G06G7/48 ,  G03F7/20 ,  G03F7/38 ,  G03F7/30

CPC classification number: G03F7/705 ,  G03F7/30 ,  G03F7/322 ,  G03F7/325 ,  G03F7/38 ,  G03F7/70125 ,  G03F7/70441 ,  G03F7/70625

Abstract: In some embodiments, a method may include improving a development process of a photoresist. The method may include simulating a negative-tone development process of a photoresist. The method may include determining a reaction of a developer with a soluble photoresist surface. Determining the reaction of the developer may include applying a reaction rate constant at a power of a reaction order to a blocked polymer concentration to yield a resist dissolution rate of soluble resist comprising the dissolution-limited regime of development. The method may include determining a flux of the developer into exposed and partially soluble resist. Determining the flux of the developer may include applying a vector valued diffusion coefficient of the developer dependent upon the blocked polymer concentration to a gradient of developer concentration to an expansion rate of insoluble resist comprising the expansion-controlled regime of development. The method may include optimizing an illumination source and a mask on a full chip.

公开(公告)号：US20170343903A1

公开(公告)日：2017-11-30

申请号：US15224290

申请日：2016-07-29

Applicant: KLA-Tencor Corporation

Inventor： Myungjun Lee ,  Mark D. Smith

IPC: G03F7/20 ,  G03F1/22

CPC classification number: G03F7/70283 ,  G03F1/22 ,  G03F1/38 ,  G03F7/70091 ,  G03F7/70625 ,  G03F7/70633 ,  G03F7/70683

Abstract: A lithography system includes an illumination source including two illumination poles separated along a first direction and symmetrically distributed around an optical axis, a pattern mask to receive illumination from the illumination source, and a set of projection optics to generate an image corresponding to the pattern mask onto a sample. The pattern mask includes a metrology target pattern mask and device pattern mask elements. The device pattern mask elements are distributed along the first direction with a device separation distance. The metrology target pattern mask includes a set of metrology target pattern mask elements having a diffraction pattern corresponding to that of the device pattern mask elements. A metrology target generated on the sample associated with the metrology target pattern mask is characterizable along a second direction and has printing characteristics corresponding to those of device pattern elements generated on the sample associated with the device pattern mask elements.