# US 2021/0333316 A1 · Measuring Temperature-Modulated Properties of a Test Sample > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0333316 A1 - Document ID: US20210333316A1 - Status: Published application - Kind: A1 - Application number: 17/235,902 - Filed: 2021-04-20 - Published: 2021-10-28 - Earliest claimed: 2020-04-24 - Assignees: KLA Corporation - Applicants: Kla Corporation - Inventors: Dirch Hjorth Petersen; Ole Hansen; Henrik Hartmann Henrichsen; Benny Guralnik - Web page: https://patentgrep.com/patent/US20210333316A1 ## CPC - G01R 31/2812: {Checking for open circuits or shorts, e.g. solder bridges; Testing conductivity, resistivity or impedance (of connections G01R31/66)} - G01R 31/2858: {Measuring of material aspects, e.g. electro-migration [EM], hot carrier injection} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - H10P 74/207: {Electrical properties, e.g. testing or measuring of resistance, deep levels or capacitance-voltage characteristics} - H10P 74/277: {Circuits for electrically characterising or monitoring manufacturing processes, e.g. circuits in tested chips or circuits in testing wafers} - G01R 31/2628: {for measuring thermal properties thereof} - G01R 31/2831: {Testing of materials or semi-finished products, e.g. semiconductor wafers or substrates (G01R31/318511 takes precedence; testing during manufacture H10P74/00)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract A physical property of a test sample with a conductive or semi-conductive material (line/area/volume) is obtained. Periodic Joule heating is induced within the test sample by passing an AC current across a first pair of probe terminals electrically connected to the test sample, measuring the voltage drop across a second pair of probe terminals electrically connected to the test sample at one and three times the fundamental excitation frequency of the current-conducting terminals, and calculating the temperature-modulated property/properties of the test sample as a function of the potential drop measurement(s). This includes: a) determining a value proportional to the TCR of the test sample, b) a geometric parameter of the test sample (affected by coupling of its TCR to heat transport to/from the test sample), or c) the true resistivity of the test sample at the ambient experimental temperature by subtracting measurable and accountable TCR offset(s). ## Claims ### Claim 1 A method for measuring a property in response to a temperature modulation of a test sample, said method comprising: providing said test sample, said test sample being made of an electrically conducting or semiconducting material; providing at least two terminals and at least two or four electrically conducting interconnections between said terminals and said electrically conducting or semiconducting material, said two or four electrically conducting interconnections contacting two or four positions at said electrically conducting or semiconducting material; providing a power source and an electric circuit for generating a current and injecting said current into said electrically conducting or semiconducting material using said terminals; measuring a voltage across a part of said electrically conducting or semiconducting material using said terminals; and determining said property as a function of a value of the third harmonic frequency component of said measured voltage. ### Claim 2 (depends on 1) The method according to claim 1, further comprising determining said property as a function of said measured voltage. ### Claim 3 (depends on 1) The method according to claim 1, wherein said property is a temperature coefficient of resistance, thermal conductance, thermal conductivity, charge carrier concentration, electrical and thermal geometry, line edge roughness, side wall angle, resistance at room/reference temperature, Peltier coefficient, Seebeck coefficient, or electrical cross section of a conductor. ### Claim 4 (depends on 1) The method according to claim 1, further comprising defining a threshold for accepting or rejecting said test sample. ### Claim 5 A method for screening a test sample, said method comprising: providing said test sample, said test sample being made of an electrically conducting or semiconducting material; providing at least two terminals, and at least two or four electrically conducting interconnections between said terminals and said electrically conducting or semiconducting material; said two or four electrically conducting interconnections contacting two or four positions at said electrically conducting or semiconducting material; providing a power source and an electric circuit for generating a current and injecting said current into said electrically conducting or semiconducting material using said terminals; measuring a voltage across a part of said electrically conducting or semiconducting material using said terminals; determining a third harmonic frequency component of said measured voltage; determining a threshold value for accepting or rejecting said test sample as a function of said third harmonic frequency component; accepting said test sample when a magnitude of said third harmonic frequency component is lower than said threshold; and rejecting said test sample when said magnitude of said third harmonic frequency component is higher than said threshold. ### Claim 6 (depends on 5) The method according to claim 5, further comprising providing a set of third harmonic frequency components of voltages measured on a set of samples. ### Claim 7 (depends on 6) The method according to claim 6, wherein said threshold is a function of said set of third harmonic frequency components. ### Claim 8 (depends on 6) The method according to claim 6, wherein said threshold is not more than 10% different than said third harmonic frequency component of said set of third harmonic frequency components having a greatest magnitude. ### Claim 9 (depends on 5) The method according to claim 5, further comprising determining an electric resistance of said electrically conducting or semiconducting material at reference temperature as a function of said current, said measured voltage, and a value of said third harmonic frequency component of said measured voltage. ### Claim 10 (depends on 5) The method according to claim 5, wherein said current has an amplitude for heating a domain or said test sample to a temperature above a background temperature. ### Claim 11 (depends on 5) The method according to claim 5, further comprising comparing said measured voltage to a set of reference values for screening a shape or determining a shape of an electrical component or interconnection. ### Claim 12 (depends on 11) The method according to claim 11, wherein said set of reference values comprises coordinates or pairs relating shapes of an electrically conducting layer or electrically conducting line is a function of voltage resulting from heating. ### Claim 13 (depends on 11) The method according to claim 11, wherein said set of reference values comprises coordinates or pairs relating shapes of an electrically conducting layer or electrically conducting line is a function of voltage at the third harmonic frequency resulting from heating. ### Claim 14 (depends on 11) The method according to claim 11, further comprising defining a target reference value in said set of reference values for accepting or rejecting said test sample. ### Claim 15 (depends on 14) The method according to claim 14, further comprising rejecting said test sample when a difference between said voltage and said target is greater than said threshold. ### Claim 16 (depends on 14) The method according to claim 14, further comprising accepting said test sample when a difference between said voltage and said target is smaller than said threshold. ### Claim 17 (depends on 11) The method according to claim 11, further comprising comparing said measured voltage to said set of reference values. ### Claim 18 A method for determining the temperature coefficient of resistance, said method comprising: providing said test sample, said test sample being made of an electrically conducting or semiconducting material; providing a set of terminals including at least four terminals and at least four electrically conducting interconnections between said terminals and said electrically conducting or semiconducting material, said four electrically conducting interconnections contacting four positions at said electrically conducting or semiconducting material; providing a power source and an electric circuit for generating a current; injecting a first current into said test sample using a first combination of two terminals from said set of terminals; measuring a first voltage using a second combination of two terminals from said set of terminals; injecting a second current into said test sample using a third combination of two terminals from said set of terminals; measuring a second voltage using a fourth combination of two terminals from said set of terminals; and determining the temperature coefficient of resistance or a value proportional to the temperature coefficient of resistance as a function of said first current, said second current, said first voltage, and said second voltage. ### Claim 19 (depends on 18) The method according to claim 18, wherein said third combination is equal to said second combination and wherein said fourth combination is equal to said first combination. ### Claim 20 (depends on 18) The method according to claim 18, wherein said first combination is different than said third combination. ### Claim 21 (depends on 18) The method according to claim 18, wherein said second combination is different than said fourth combination.