# US 12,326,410 B2 · Electron spectroscopy based techniques for determining various chemical and electrical characteristics of samples > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,326,410 B2 - Document ID: US12326410B2 - Status: Granted - Kind: B2 - Application number: 18/002,848 - Filed: 2021-06-28 - Published: 2023-09-14 - Granted: 2025-06-10 - Earliest claimed: 2020-06-28 - Assignees: Cozai Ltd - Applicants: Cozai Ltd - Inventors: Hagai Cohen - Web page: https://patentgrep.com/patent/US12326410B2 ## CPC - G01N 23/2251: using incident electron beams, e.g. scanning electron microscopy [SEM] - G01N 21/64: Fluorescence; Phosphorescence - G01N 23/2273: Measuring photoelectron spectrum, e.g. electron spectroscopy for chemical analysis [ESCA] or X-ray photoelectron spectroscopy [XPS] - G01R 31/307: of integrated circuits - G01N 2223/079: incident electron beam and measuring excited X-rays - G01N 2223/085: photo-electron spectrum [ESCA, XPS] - G01N 2223/304: electric circuits, signal processing - G01N 2223/306: computer control - G01N 2223/405: mapping of a material property - G01N 2223/6116: semiconductor wafer - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A measurement system and method are presented for measuring one or more parameters of a sample. The measurement system comprises an excitation system and a detection system. The excitation system is configured to generate combined exciting radiation comprising one- or multi-parameter modulation of multiple exciting signals of different types to be applied to at least a portion of a sample under measurements to thereby induce electron emission response of said at least portion of the sample to said combined exciting radiation. The detection system is configured for detecting the electron emission response of the at least portion of the sample and generating measured data indicative of a modulated change of an electrical state of the at least portion of the sample, thereby enabling determination of one or more parameters of the sample from the measured data. ## Claims ### Claim 1 A measurement system for measuring a sample, the measurement system comprising: an excitation system comprising a plurality of excitation sources generating excitations of different types comprising: a high energy radiation source generating high energy radiation and at least one of the following: at least one relatively low-energy particles' source generating at least one wide beam; at least one electron beam source generating e-radiation in the form of a focused electron beam; a light source generating illumination including one or more optical beams; and at least one electric power supply providing a bias voltage to a sample; a signal modulation system associated with at least two of said excitation sources, thereby providing that each of at least two respective excitations is a modulated excitation having a predetermined modulation profile during each of at least one measurement session, such that the excitations of the different types including the at least two modulated excitations, when concurrently applied to at least a region of the sample, differently affect said at least region of the sample inducing responses of the sample including responses to the different modulated excitations indicative of various different information pieces about the sample, forming together a combined effective response of the sample embedding multiple data about the sample; a detection system comprising at least an electron spectrometer and being configured and operable for detecting the effective response of said at least region of the sample to the multiple excitations including said at least two modulated excitations and generating measured data indicative of the detected effective response, which is indicative of a modulated change of electrical state of at least said region of the sample; a control unit configured for signal communication with the detector to process the measured data, utilizing modulation data about the predetermined modulation profile for each of said at least two modulated excitations, and determine one or more of the parameters/conditions of said at least region of the sample. ### Claim 2 (depends on 1) The system according to claim 1, wherein: the high energy radiation source comprises at least one of X-ray source and electron beam source configured and operable for irradiating a surface region of the sample and causing emission of electrons therefrom. ### Claim 3 (depends on 1) The system according to claim 1, wherein said at least one relatively low-energy particles' source comprises at least one of electron beam source and ion beam source. ### Claim 4 (depends on 1) The system according to claim 1, wherein the control unit is configured and operable to operate the excitation system and the modulation system to concurrently excite at least a portion of the sample by the high energy radiation and excite at least one spot within said at least portion by either one or both of the focused electron beam and the focused illumination. ### Claim 5 (depends on 1) The system according to claim 1, wherein the control unit is configured and operable to utilize the modulation data used to generate said at least two modulated beams, and demodulate the measured data to extract therefrom information about the sample. ### Claim 6 (depends on 3) The system according to claim 3, wherein the control unit is configured and operable to demodulate the measured data to extract therefrom data associated with the excited location of the sample. ### Claim 7 (depends on 1) The system according to claim 1, wherein the modulation system is configured and operable to modulate at least one of the exciting signals, the detected effective response being indicative of one or more of the following properties of said at least region of the sample: conduction integrity of leads; work function; combined optical and electrical measurement results. ### Claim 8 (depends on 1) The system according to claim 1, wherein the modulation system is configured and operable to modulate the at least two of the exciting signals, the detected effective response being indicative of one or more of the following properties of said at least region of the sample: I-V and V-V characteristics; vertically and/or laterally resolved electrostatic potential: chemical analysis results of a small spot in said region: soft breakdown of elements. ### Claim 9 (depends on 1) The system according to claim 1, wherein the wide beam, when modulated, has one or more of the following modulations: current amplitude modulation at a certain frequency; landing energy modulation at a certain frequency. ### Claim 10 (depends on 1) The system according to claim 1, wherein the illumination includes at least one optical beam, which when modulated, has at least one of the following modulations: wavelength modulation around a selected wavelength, polarization modulation, amplitude modulation, temporal frequency modulation. ### Claim 11 (depends on 1) The system according to claim 1, wherein the optical light source system is configured and operable to produce the illumination in the form of two or more optical beams differing from one another in at least one of the following parameters: wavelength, amplitude, polarization, temporal frequency. ### Claim 12 (depends on 1) The system according to claim 1, wherein the electric power supply is operable by the modulator to produce modulated biasing voltage according to a predetermined time function. ### Claim 13 (depends on 1) The system according to claim 1, wherein the electron source is configured and operable by the modulator to produce the modulated focused electron beam for exciting a region of the sample containing, or at least partially intersecting with, a surface portion of the sample excited by the high energy radiation. ### Claim 14 (depends on 4) The system according to claim 4, wherein the illumination is modulated to periodically excite the spot in said portion of the sample. ### Claim 15 (depends on 1) The system according to claim 1, wherein the excitation system and the modulation system are configured and operable to produce first and second focused beams for exciting first and second distant regions of the sample, wherein at least one of said first and second beams is modulated and wherein one of the first and second spots is contained or at least partially intersects with a surface portion of the sample excited by the high energy radiation. ### Claim 16 (depends on 1) The system according to claim 1, wherein the excitation system and the modulation system are configured and controllably operated to provide multi-parameter modulation of the excitation signals to thereby determine a two-dimensional or three-dimensional map of chemical composition and/or electrical properties of the sample. ### Claim 17 (depends on 1) The system according to claim 1, wherein the excitation system and the modulation system are configured and operable to excite a relatively small region of the sample by modulated focused excitation including at least one of the electron beam and the illumination within a relatively large portion of the sample excited by either one or both of the high energy radiation and the wide charged particle beam, thereby inducing modification of an effective voltage of said relatively small region and enabling extraction of contribution of said region in the detected effective response of the sample. ### Claim 18 (depends on 1) The system according to claim 1, configured and operable to measure chemical and/or electrical properties of a selected domain in the sample, said excitations comprising a pattern of applied excitations formed by a combination of phase differences and modulation frequencies of the excitations of different types, thereby enabling to extract from the effective response of the sample characteristic X-ray photoelectron spectroscopy (XPS) line shifts indicative of said selected domain. ### Claim 19 (depends on 18) The system according to claim 18, wherein said combination of phase differences and modulation frequencies of the excitations of different types comprises the bias voltage and the wide beam e-radiation gradually changing in opposite directions w % bile exciting the sample concurrently with excitation of the sample with the high energy radiation. ### Claim 20 (depends on 18) The system according to claim 18, configured and operable to perform a lateral scan of said sample's domain, by applying either one or both of the modulated illumination and modulated focused e-radiation. ### Claim 21 (depends on 1) The system according to claim 1, wherein the detection system comprises a detector comprising an array of sensor elements each configured to generate measured data piece indicative of an amount of electrons emitted from the sample with a certain kinetic energy based on relative location of said sensor element in said array of sensor elements. ### Claim 22 (depends on 1) The system according to claim 1, wherein the detection system comprises an optical detector for detecting an optical response of the sample to the multiple excitations. ### Claim 23 (depends on 1) The system according to claim 1, comprising an illuminator and an optical detector configured and operable to perform optical measurements of the sample. ### Claim 24 (depends on 23) The system according to claim 23, wherein said illuminator comprises said light source unit for producing said exciting illumination. ### Claim 25 A measurement system for measuring one or more parameters of a sample, the measurement system comprising: an excitation system configured and operable to generate combined exciting radiation comprising multi-parameter modulation of multiple exciting signals of different types to be applied to at least a portion of a sample under measurements to thereby differently affect said at least portion of the sample by the multiple exciting signals of different types characterized by the multi-parameter modulation and induce electron emission response of said at least portion of the sample to said combined exciting radiation, said electron emission response being therefore indicative of various different information pieces about the sample; a detection system for detecting the electron emission response of said at least portion of the sample and generating measured data indicative of a modulated change of an electrical state of said at least portion of the sample, thereby enabling to utilize predetermined modulation data about modulation profiles of the multi-parameter modulation of the multiple exciting signals of different types for determination of one or more parameters of the sample from said measured data. ### Claim 26 (depends on 1) The system according to claim 1, wherein the electron emission response is indicative of secondary electron emission from the sample induced by the combined excitation of the sample and a detectable change of an electric parameter of the sample being excited by said combined excitation. ### Claim 27 A method for measuring parameters of a sample, the method comprising: performing at least one measurement session on the sample and obtaining at least one corresponding measured data, wherein said performing of the measurement session comprises: concurrently exciting at least a portion of the sample by multiple excitations of different types comprising at least two modulated excitations, each having a predetermined modulation profile, such that the multiple excitations of the different types including the at least two modulated excitations differently affect said at least portion of the sample inducing responses of the sample including responses to the different modulated excitations indicative of various different information pieces about the sample, forming together a combined effective response of the sample embedding multiple data about the sample, said multiple excitations comprising high energy irradiation, and one or more of the following: at least one wide beam of relatively low-energy charged particles, e-radiation comprising a focused electron beam, illumination comprising one or more light beams, and an electrical power supply providing at least sample bias voltage; detecting the combined effective response of said at least portion of the sample to said multiple excitations indicative of at least electron emission of the sample; and generating the measured data indicative of the detected combined effective response, processing said measured data utilizing modulation data about the predetermined modulation profile for each of said at least two modulated excitations and determining one or more parameters of the sample within said at least portion of the sample. ### Claim 28 (depends on 27) The method according to claim 27, wherein the high energy radiation comprises X-ray radiation or electron beam radiation. ### Claim 29 (depends on 27) The method according to claim 27, wherein said at least one wide beam of relatively low-energy particles comprises at least one of electron beam and ion beam. ### Claim 30 (depends on 27) The method according to claim 27, comprising controlling the excitation and modulation procedures to concurrently excite at least a portion of the sample by the high energy radiation and excite at least one spot within said at least portion by either one or both of the focused electron beam and the illumination. ### Claim 31 (depends on 27) The method according to claim 27, wherein said processing comprises utilizing the modulation data used to generate the predetermined number of modulated beams, and demodulate the measured data to extract therefrom information about the sample. ### Claim 32 (depends on 31) The method according to claim 31, wherein said processing comprises demodulating the measured data to extract therefrom data associated with the excited location of the sample. ### Claim 33 (depends on 27) The method according to claim 27, wherein the detected effective response is indicative of one or more of the following properties of said at least region of the sample: conduction integrity of leads; work function; combined optical and electrical measurement results. ### Claim 34 (depends on 27) The method according to claim 27, wherein the detected effective response is indicative of one or more of the following properties of said at least region of the sample: I-V and V-V characteristics; vertically and/or laterally resolved electrostatic potential; chemical analysis results of a small spot in said region; soft breakdown of elements. ### Claim 35 (depends on 27) The method according to claim 27, wherein the wide beam has one or more of the following modulations: current amplitude modulation at a certain frequency; landing energy modulation at a certain frequency. ### Claim 36 (depends on 27) The method according to claim 27, wherein the illumination includes at least one optical beam having at least one of the following modulations: wavelength modulation, polarization modulation, amplitude modulation, temporal frequency modulation. ### Claim 37 (depends on 27) The method according to claim 27, wherein the illumination is in the form of two or more optical beams differing from one another in at least one of the following parameters: wavelength, amplitude, polarization, temporal frequency or phase. ### Claim 38 (depends on 27) The method according to claim 27, wherein the electric power supply comprises biasing voltage modulation according to a predetermined time function. ### Claim 39 (depends on 27) The method according to claim 27, wherein the at least one modulated beam, being electron beam or focused light beam, excites at least one region of the sample containing, or at least partially intersecting with, a surface portion of the sample excited by the high energy radiation beam. ### Claim 40 (depends on 39) The method according to claim 39, wherein the at least one modulated beam, being electron beam or focused light beam, excites at least one additional region of the sample located outside said surface portion of the sample excited by the high energy radiation beam. ### Claim 41 (depends on 27) The method according to claim 27, wherein the illumination is modulated to periodically excite the spot in said portion of the sample. ### Claim 42 (depends on 27) The method according to claim 27, wherein the excitation comprises first and second focused beams for exciting first and second distant regions of the sample, wherein at least one of the first and second beams is modulated and wherein one of the first and second spots is contained or at least partially intersects with a surface portion of the sample excited by the high energy radiation beam. ### Claim 43 (depends on 27) The method according to claim 27, wherein the excitation comprises multi-parameter modulation of the excitation signals to thereby determine a two-dimensional or three-dimensional map of chemical composition and/or electrical properties of the sample. ### Claim 44 (depends on 27) The method according to claim 27, wherein said at least one measurement session comprises exciting a relatively small region of the sample by modulated focused excitation including at least one of the electron beam and the illumination within a relatively large portion of the sample excited by either one or both of the high energy radiation and the wide charged particle beam, thereby inducing modification of an effective voltage of said relatively small region and enabling extraction of contribution of said region in the detected effective response of the sample. ### Claim 45 (depends on 27) The method according to claim 27, comprising measuring chemical and/or electrical properties of a selected domain in the sample, said excitations comprising a pattern of applied excitations formed by a combination of phase differences and modulation frequencies of the excitations of different types, thereby enabling to extract, from the effective response of the sample, characteristic X-ray photoelectron spectroscopy (XPS) line shifts indicative of said selected domain. ### Claim 46 (depends on 45) The method according to claim 45, wherein said combination of phase differences and modulation frequencies of the excitations of different types comprises the bias voltage and the wide beam e-radiation gradually changing in opposite directions while exciting the sample concurrently with excitation of the sample with the high energy radiation. ### Claim 47 (depends on 46) The method according to claim 46, wherein said measurement session comprises performing a lateral scan of said sample's domain, by applying either one or both of the modulated illumination and modulated focused e-radiation. ### Claim 48 (depends on 27) The method according to claim 27, wherein said detecting utilizes an array of sensor elements each configured to generate measured data piece indicative of an amount of electrons emitted from the sample with a certain kinetic energy based on relative location of said sensor element in said array of sensor elements. ### Claim 49 (depends on 27) The method according to claim 27, wherein said detecting further comprises detecting an optical response of the sample to the multiple excitations. ### Claim 50 (depends on 27) The method according to claim 27, further comprising performing optical measurements on the sample. ### Claim 51 (depends on 27) The method according to claim 27, comprising: sequentially performing two or more of the measurement sessions on the sample differing from one another by a combination of said multiple excitations of the different types and obtaining respective two or more corresponding measured data, each indicative of the detected combined effective response. ### Claim 52 (depends on 27) The method according to claim 27, wherein said sample comprises an integrated circuit structure. ### Claim 53 (depends on 52) The method according to claim 52, wherein said integrated circuit structure comprises a high-K dielectric layer. ### Claim 54 (depends on 27) The method according to claim 27, wherein said sample comprises a semiconductor wafer. ### Claim 55 (depends on 27) The method according to claim 27, wherein said sample comprises a patterned structure. ### Claim 56 (depends on 55) The method according to claim 55, wherein the patterned structure defines an array of memory cells. ### Claim 57 (depends on 55) The method according to claim 55, wherein the patterned structure defines an array of transistors of logic IC.