公开(公告)号：US20210010948A1

公开(公告)日：2021-01-14

申请号：US16921738

申请日：2020-07-06

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  Yinying Xiao-Li ,  Elena Loginova ,  John Fielden

IPC: G01N21/95 ,  G02B27/10 ,  G02B1/113 ,  G01N21/88

Abstract: Strontium tetraborate can be used as an optical material. Strontium tetraborate exhibits high refractive indices, high optical damage threshold, and high microhardness. The transmission window of strontium tetraborate covers a very broad range of wavelengths, from 130 nm to 3200 nm, making the material particularly useful at VUV wavelengths. An optical component made of strontium tetraborate can be incorporated in an optical system, such as a semiconductor inspection system, a metrology system, or a lithography system. These optical components may include mirrors, lenses, lens arrays, prisms, beam splitters, windows, lamp cells or Brewster-angle optics.

公开(公告)号：US20240426021A1

公开(公告)日：2024-12-26

申请号：US18588822

申请日：2024-02-27

Applicant: KLA Corporation

Inventor： Kelly Mauser ,  Yung-Ho Alex Chuang ,  Baigang Zhang ,  Xuefeng Liu ,  John Fielden ,  Elena Loginova Casey

IPC: C30B17/00 ,  C30B29/10 ,  C30B33/06 ,  C30B35/00 ,  G02F1/35 ,  G02F1/355 ,  G02F1/37

Abstract: A method for growing a periodically-poled nonlinear crystal may include placing a seed crystal into a melt to form a seed crystal melt mixture, where the seed crystal may include at least one of strontium tetraborate (SBO) or lithium triborate (LBO), and where the melt includes at least one of a mixture of Sr, B, and O or a mixture of Li, B, and O. The method may further include heating the seed crystal melt mixture to a predetermined temperature until the periodically-poled nonlinear crystal forms.

公开(公告)号：US12152316B1

公开(公告)日：2024-11-26

申请号：US17532685

申请日：2021-11-22

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  Vladimir Dribinski

IPC: C30B33/02 ,  C30B7/00 ,  C30B9/00 ,  C30B29/10 ,  C30B29/22 ,  G01N21/95 ,  G01N21/956 ,  G01N21/84 ,  G01N21/87

Abstract: The passivation of a nonlinear optical crystal for use in an inspection tool includes growing a nonlinear optical crystal in the presence of at least one of fluorine, a fluoride ion and a fluoride-containing compound, mechanically preparing the nonlinear optical crystal, performing an annealing process on the nonlinear optical crystal and exposing the nonlinear optical crystal to a hydrogen-containing or deuterium-containing passivating gas.

公开(公告)号：US11879853B2

公开(公告)日：2024-01-23

申请号：US17672832

申请日：2022-02-16

Applicant: KLA Corporation

Inventor： Xuefeng Liu ,  Jenn-Kuen Leong ,  Yung-Ho Alex Chuang ,  John Fielden

IPC: G01N21/95 ,  G01N21/47 ,  G02B27/28 ,  H04N23/56 ,  H04N23/75

CPC classification number: G01N21/9501 ,  G01N21/47 ,  G02B27/281 ,  G02B27/283 ,  H04N23/56 ,  H04N23/75

Abstract: An inspection system may include an illumination source to generate an illumination beam, illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, and collection optics to collect scattered light from the sample in a dark-field mode, where the scattered light from the sample includes surface haze associated with light scattered from a surface of the sample, and where at least a at least a portion of the surface haze has elliptical polarizations. The system may further include pupil-plane optics to convert the polarizations of the surface haze across the pupil to linear polarization that is aligned parallel to a selected haze orientation direction. The system may include a linear polarizer to reject the surface haze aligned parallel to this haze orientation direction and a detector to generate a dark-field image of the sample based on light passed by the linear polarizer.

公开(公告)号：US11719652B2

公开(公告)日：2023-08-08

申请号：US17160006

申请日：2021-01-27

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  John Fielden

IPC: G01N23/20008 ,  G01N23/201 ,  H01J35/06 ,  H01J35/14 ,  H01J35/18 ,  H01J3/02 ,  H05G1/02 ,  G03F7/20 ,  G03F7/00

CPC classification number: G01N23/20008 ,  G01N23/201 ,  G03F7/70633 ,  H01J3/022 ,  H01J35/065 ,  H01J35/066 ,  H01J35/147 ,  H01J35/18 ,  H05G1/02 ,  G01N2223/03 ,  G01N2223/054 ,  G01N2223/1016 ,  G01N2223/204 ,  G01N2223/6116 ,  H01J2235/062 ,  H01J2235/068 ,  H01J2235/16 ,  H01J2235/18

Abstract: Methods and systems for realizing a high radiance x-ray source based on a high density electron emitter array are presented herein. The high radiance x-ray source is suitable for high throughput x-ray metrology and inspection in a semiconductor fabrication environment. The high radiance X-ray source includes an array of electron emitters that generate a large electron current focused over a small anode area to generate high radiance X-ray illumination light. In some embodiments, electron current density across the surface of the electron emitter array is at least 0.01 Amperes/mm2, the electron current is focused onto an anode area with a dimension of maximum extent less than 100 micrometers, and the spacing between emitters is less than 5 micrometers. In another aspect, emitted electrons are accelerated from the array to the anode with a landing energy less than four times the energy of a desired X-ray emission line.

公开(公告)号：US20230185158A1

公开(公告)日：2023-06-15

申请号：US17991198

申请日：2022-11-21

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  Kelly Mauser ,  Baigang Zhang ,  Xuefeng Liu ,  John Fielden ,  Yinying Xiao-Li ,  Elena Loginova

IPC: G02F1/35 ,  G02F1/355 ,  G02F1/39 ,  G02F1/37 ,  G01N21/47

CPC classification number: G02F1/3534 ,  G01N21/4738 ,  G02F1/37 ,  G02F1/392 ,  G02F1/3507 ,  G02F1/3542 ,  G02F1/3548 ,  G02F1/3551 ,  H01S3/1625

Abstract: A nonlinear crystal including stacked strontium tetraborate SrB4O7 (SBO) crystal plates that are cooperatively configured to create a periodic structure for quasi-phase-matching (QPM) is used in the final frequency doubling stage of a laser assembly to generate laser output light having a wavelength in the range of about 180 nm to 200 nm. One or more fundamental laser beams are frequency doubled, down-converted and/or summed using one or more frequency conversion stages to generate an intermediate frequency light with a corresponding wavelength in the range of about 360 nm to 400 nm, and then the final frequency converting stage utilizes the nonlinear crystal to double the frequency of the intermediate frequency light to generate the desired laser output light at high power. Methods, inspection systems, lithography systems and cutting systems incorporating the laser assembly are also described.

公开(公告)号：US20230161221A1

公开(公告)日：2023-05-25

申请号：US18087236

申请日：2022-12-22

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  Yinying Xiao-Li ,  Elena Loginova ,  John Fielden ,  Baigang Zhang ,  Xuefeng Liu ,  Kelly Ann Weekley Mauser

IPC: G02F1/35 ,  G02F1/355

CPC classification number: G02F1/354 ,  G02F1/3551 ,  G02F1/3548 ,  G02F1/3507 ,  G02F1/3503

Abstract: A nonlinear crystal grating assembly including two integral nonlinear crystal grating structures having inverted crystal axes and having parallel spaced-apart mesas with predetermined mesa widths arranged such that, when assembled in an interdigitated configuration, the mesas of the two grating structures form an alternating grating pattern that is aligned with a propagation direction of input light, thereby creating a periodic structure for quasi-phase-matching (QPM). The nonlinear crystal grating structures are formed using strontium tetraborate, lithium triborate or another nonlinear crystal material. The nonlinear crystal grating assembly is utilized in a laser assembly in which fundamental wavelengths are doubled and/or summed using intermediate frequency conversion stages, and then a final frequency converting stage utilizes the nonlinear crystal grating assembly to double or sum one or more intermediate light beam frequencies to generate laser output light at high power and photon energy levels. A method and inspection system are also described.

公开(公告)号：US20220336180A1

公开(公告)日：2022-10-20

申请号：US17858943

申请日：2022-07-06

Applicant: KLA Corporation

Inventor： Edgardo Garcia Berrios ,  J. Joseph Armstrong ,  Yinying Xiao-Li ,  John Fielden ,  Yung-Ho Alex Chuang

IPC: H01J1/304 ,  H01J3/02 ,  H01J37/073

Abstract: A light modulated electron source utilizes a photon-beam source to modulate the emission current of an electron beam emitted from a silicon-based field emitter. The field emitter's cathode includes a protrusion fabricated on a silicon substrate and having an emission tip covered by a coating layer. An extractor generates an electric field that attracts free electrons toward the emission tip for emission as part of the electron beam. The photon-beam source generates a photon beam including photons having an energy greater than the bandgap of silicon, and includes optics that direct the photon beam onto the emission tip, whereby each absorbed photon creates a photo-electron that combines with the free electrons to enhance the electron beam's emission current. A controller modulates the emission current by controlling the intensity of the photon beam applied to the emission tip. A monitor measures the electron beam and provides feedback to the controller.

公开(公告)号：US11417492B2

公开(公告)日：2022-08-16

申请号：US17020277

申请日：2020-09-14

Applicant: KLA Corporation

Inventor： Edgardo Garcia Berrios ,  J. Joseph Armstrong ,  Yinying Xiao-Li ,  John Fielden ,  Yung-Ho Alex Chuang

IPC: H01J1/304 ,  H01J3/02 ,  H01J37/073 ,  H01J35/06 ,  H01J37/28 ,  H01J37/317

Abstract: A light modulated electron source utilizes a photon-beam source to modulate the emission current of an electron beam emitted from a silicon-based field emitter. The field emitter's cathode includes a protrusion fabricated on a silicon substrate and having an emission tip covered by a coating layer. An extractor generates an electric field that attracts free electrons toward the emission tip for emission as part of the electron beam. The photon-beam source generates a photon beam including photons having an energy greater than the bandgap of silicon, and includes optics that direct the photon beam onto the emission tip, whereby each absorbed photon creates a photo-electron that combines with the free electrons to enhance the electron beam's emission current. A controller modulates the emission current by controlling the intensity of the photon beam applied to the emission tip. A monitor measures the electron beam and provides feedback to the controller.

公开(公告)号：US20210389643A1

公开(公告)日：2021-12-16

申请号：US17239561

申请日：2021-04-24

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  Yinying Xiao-li ,  Elena Loginova ,  John Fielden ,  Baigang Zhang

IPC: G02F1/355 ,  G02F1/35

Abstract: A nonlinear crystal including stacked Strontium tetraborate SrB4O7 (SBO) crystal plates that are cooperatively configured to create a periodic structure for quasi-phase-matching (QPM) is used in the final frequency converting stage of a laser assembly to generate laser output light having a wavelength in the range of 125 nm to 183 nm. One or more fundamental light beams having fundamental wavelengths between 1 and 1.1 μm are doubled and/or summed using multiple intermediate frequency conversion stages to generate one or more intermediate light beam frequencies (e.g., second through eighth harmonics, or sums thereof), and then the final frequency converting stage utilizes the nonlinear crystal to either double a single intermediate light beam frequency or to sum two intermediate light beam frequencies to generate the desired laser output light at high power and photon energy levels. A method and inspection system incorporating the laser assembly is also described.