Measure Thickness of Magnetic Thin-Film Based on the Capacitance-to-frequency Signal Conversion

Abstract

According to wave-absorbing material's electricity characteristic, this text created a kind of new high-performance, low-cost capacitance type absorbing-wave coat's thickness measuring system. Carry out a research of thin film measurement which from nm-level to micron-level. According to the theory which capacitor working in electric field, it design a special single-piece capacitance sensor. This system can carry on a measurement to the thickness of thin film from nm-level to micron-level. The use of capacitance / frequency (C / F) method, the system can automatically tune to zero, calibrate and eliminate most of the error, so the system structure is very simple.