Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Patent
1995-11-16
1997-11-25
Karlsen, Ernest F.
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
324715, 324719, 324718, 437 8, G01R 3102
Patent
active
056916485
ABSTRACT:
A method and apparatus for measuring sheet resistance and thickness of thin films and substrates. A four-point probe assembly engages the surface of a film on a substrate, and the thickness of the substrate is determined from the point of contact between the probes and film. A measuring apparatus then outputs a voltage waveform which applies a voltage to probes of the probe assembly. An inverter inverts the voltage and provides the inverted voltage on another probe of the probe assembly, thus inducing a current in these probes of the four point probe and through the surface of the film. Two other probes measure a voltage in the film created by the current. The voltages on the current probes provide a voltage close to zero at the other probes, thus allowing these other probes to measure voltages with greater precision. The current created by the voltage waveform and the voltage created across the inner probes are measured for each voltage level of the waveform. A sheet resistance of the film is determined by calculating the slope of a least square fit line of the measured current and voltage. The sheet resistance is proportional to the slope of the least square line. The thickness of the film is calculated by dividing the film resistivity by the calculated sheet resistance.
REFERENCES:
patent: 2659861 (1953-11-01), Branson
patent: 2659862 (1953-11-01), Branson
patent: 3601693 (1971-08-01), Lorentzen
patent: 3676775 (1972-07-01), Dupnock et al.
patent: 3735254 (1973-05-01), Severin
patent: 4048558 (1977-09-01), Goodman
patent: 4267506 (1981-05-01), Shiell
patent: 4335350 (1982-06-01), Chen
patent: 4446424 (1984-05-01), Chatanier
patent: 4546318 (1985-10-01), Bowden
patent: 4667149 (1987-05-01), Cohen et al.
patent: 4703252 (1987-10-01), Perloff et al.
patent: 4706015 (1987-11-01), Chen
patent: 4755746 (1988-07-01), Mallory et al.
patent: 4758777 (1988-07-01), Bossard
patent: 4907931 (1990-03-01), Mallory et al.
patent: 4989154 (1991-01-01), Yamashita et al.
patent: 5006809 (1991-04-01), Mang et al.
patent: 5144253 (1992-09-01), Blanchard
patent: 5377071 (1994-12-01), Moslehi
patent: 5386188 (1995-01-01), Minneman
patent: 5461358 (1995-10-01), Ravas
Karlsen Ernest F.
Solis Jose M.
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