公开(公告)号：US12072606B2

公开(公告)日：2024-08-27

申请号：US17862133

申请日：2022-07-11

Applicant: KLA Corporation

Inventor： John Fielden ,  Yung-Ho Alex Chuang

IPC: G02F1/355 ,  G01N21/95 ,  G03F7/00

CPC classification number: G02F1/3551 ,  G01N21/9501 ,  G03F7/7015 ,  G03F7/70591 ,  G01N2201/068

Abstract: An amorphous layer is used as a protective coating for hygroscopic nonlinear optical crystals. The amorphous layer consists of one or more alkali metal borates and/or alkali earth metal borates. The amorphous layer slows or prevents water and/or oxygen from diffusing into the hygroscopic nonlinear optical crystal, thus simplifying handling, storage and operating environmental requirements. One or multiple additional coating layers may be placed on top of the amorphous layer, with the additional coating layers including conventional optical materials. The thicknesses of the amorphous layer and/or additional layers may be chosen to reduce reflectance of the optical component at one or more specific wavelengths. The coated nonlinear optical crystal is used in an illumination source utilized in a semiconductor inspection system, a metrology system, or a lithography system.

公开(公告)号：US20240243143A1

公开(公告)日：2024-07-18

申请号：US18391595

申请日：2023-12-20

Applicant: KLA Corporation

Inventor： Evgeniia Butaeva ,  Sisir Yalamanchili ,  Larissa Juschkin ,  John Fielden ,  Ting Fung Chung ,  Francisco Kole

IPC: H01L27/146 ,  G01N21/95

CPC classification number: H01L27/1462 ,  G01N21/9501 ,  H01L27/14636 ,  H01L27/1464 ,  H01L27/14685 ,  G02B1/11

Abstract: Back-illuminated image sensors for detecting short wavelength radiation (e.g., deep ultraviolet (DUV) and vacuum ultraviolet (VUV) light) include a semiconductor membrane, circuit elements formed on a frontside surface of the semiconductor membrane, and a pure boron coating on the backside surface of the semiconductor membrane. A two-part anti-reflective coating is formed over the pure boron coating and includes a thin oxide or nitride protection layer disposed between the pure boron coating and a fluoride-based anti-reflection layer. A method for fabricating the image sensors may include performing plasma atomic layer deposition (plasma ALD) processes to sequentially generate the pure boron coating, the oxide/nitride protection layer and then the fluoride-based anti-reflection layer. The image sensors may be configured as charge coupled devices (CCDs), complementary metal oxide semiconductor (CMOS) sensors, or as photodiodes, and arranged as two-dimensional (2D) area sensors or a one-dimensional (1D) array sensors.

公开(公告)号：US12015046B2

公开(公告)日：2024-06-18

申请号：US17544413

申请日：2021-12-07

Applicant: KLA Corporation

Inventor： Sisir Yalamanchili ,  John Fielden ,  Francisco Kole ,  Yung-Ho Alex Chuang

IPC: H01L27/146 ,  G03F7/00

CPC classification number: H01L27/14698 ,  G03F7/70033 ,  H01L27/1464

Abstract: Back-illuminated DUV/VUV/EUV radiation or charged particle image sensors are fabricated using a method that utilizes a plasma atomic layer deposition (plasma ALD) process to generate a thin pinhole-free pure boron layer over active sensor areas. Circuit elements are formed on a semiconductor membrane's frontside surface, and then an optional preliminary hydrogen plasma cleaning process is performed on the membrane's backside surface. The plasma ALD process includes performing multiple plasma ALD cycles, with each cycle including forming an adsorbed boron precursor layer during a first cycle phase, and then generating a hydrogen plasma to convert the precursor layer into an associated boron nanolayer during a second cycle phase. Gasses are purged from the plasma ALD process chamber after each cycle phase. The plasma ALD cycles are repeated until the resulting stack of boron nanolayers has a cumulative stack height (thickness) that is equal to a selected target thickness.

公开(公告)号：US11715615B2

公开(公告)日：2023-08-01

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 ,  H01J35/06 ,  H01J37/28 ,  H01J37/317

CPC classification number: H01J1/3044 ,  H01J3/022 ,  H01J37/073 ,  H01J35/065 ,  H01J37/28 ,  H01J37/3174

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：US20220268710A1

公开(公告)日：2022-08-25

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 ,  H04N5/225 ,  H04N5/238 ,  G02B27/28

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：US20210272791A1

公开(公告)日：2021-09-02

申请号：US17322651

申请日：2021-05-17

Applicant: KLA Corporation

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

IPC: H01J61/067 ,  G01N21/88 ,  H01J61/10

Abstract: A broadband ultraviolet illumination source for a characterization system is disclosed. The broadband ultraviolet illumination source includes an enclosure having one or more walls, the enclosure configured to contain a gas, and a plasma discharge device based on a graphene-dielectric-semiconductor (GOS) planar-type structure. The GOS structure includes a silicon substrate having a top surface, a dielectric layer disposed on the top surface of the silicon substrate, and at least one layer of graphene disposed on a top surface of the dielectric layer. A metal contact may be formed on the top surface of the graphene layer. The GOS structure has several advantages for use in an illumination source, such as low operating voltage (below 50 V), planar surface electron emission, and compatibility with standard semiconductor processes. The broadband ultraviolet illumination source further includes electrodes placed inside the enclosure or magnets placed outside the enclosure to increase the current density.

公开(公告)号：US20210164918A1

公开(公告)日：2021-06-03

申请号：US17175179

申请日：2021-02-12

Applicant: KLA Corporation

Inventor： Xuefeng Liu ,  Jenn-Kuen Leong ,  Daniel Kavaldjiev ,  John Fielden

IPC: G01N21/95 ,  G01N21/956 ,  G01N21/21 ,  H01L21/66 ,  G01N21/88

Abstract: A system may include illumination optics to direct an illumination beam to a sample at an off-axis angle, collection optics to collect scattered light from the sample, and a phase mask located at a first pupil plane to provide different phase shifts for light in two or more pupil regions of a collection area to reshape a point spread function of light scattered from one or more particles on a surface of the sample. The system may further include a polarization rotator located at a second pupil plane, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from the surface of the sample to a selected polarization angle, a polarizer to reject light polarized along the selected polarization angle, and a detector to generate a dark-field image of the sample based on light passed by the polarizer.

公开(公告)号：US11424117B2

公开(公告)日：2022-08-23

申请号：US17322651

申请日：2021-05-17

Applicant: KLA Corporation

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

IPC: H01J61/067 ,  G01N21/88 ,  H01J61/10 ,  G01N21/95

Abstract: A broadband ultraviolet illumination source for a characterization system is disclosed. The broadband ultraviolet illumination source includes an enclosure having one or more walls, the enclosure configured to contain a gas, and a plasma discharge device based on a graphene-dielectric-semiconductor (GOS) planar-type structure. The GOS structure includes a silicon substrate having a top surface, a dielectric layer disposed on the top surface of the silicon substrate, and at least one layer of graphene disposed on a top surface of the dielectric layer. A metal contact may be formed on the top surface of the graphene layer. The GOS structure has several advantages for use in an illumination source, such as low operating voltage (below 50 V), planar surface electron emission, and compatibility with standard semiconductor processes. The broadband ultraviolet illumination source further includes electrodes placed inside the enclosure or magnets placed outside the enclosure to increase the current density.

公开(公告)号：US20220136981A1

公开(公告)日：2022-05-05

申请号：US17576528

申请日：2022-01-14

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：US20210239629A1

公开(公告)日：2021-08-05

申请号：US17160006

申请日：2021-01-27

Applicant: KLA Corporation

Inventor： Yung-Ho Alex Chuang ,  John Fielden

IPC: G01N23/20008 ,  G01N23/207 ,  G01N23/201 ,  G03F7/20

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.