The Doppler Broadening Spectroscopy Used As Kapton Thickness Sensor.

The Doppler Broadening Spectroscopy (DBS) was used to measure Kapton film thickness, varied in 0.3-30 mils range, with Ge68 positron source and pure copper (Cu), nickel (Ni) or aluminum (Al) metals as targets. The linear relationship between S-parameter and Kapton thickness was found for Cu and Ni with sensitivity depending whether the film was used on one or two sides. LYS-1¹ (Layers Profile Analysis) program was applied to determine backscatter and absorption coefficients and subsequently absorption fractions for multi-layer system with “backing-target-Kapton-source” layers in symmetrical and non-symmetrical arrangements. The experimental and theoretical S-parameter values for multilayers system with varied Kapton film thickness show a good correlation, but its precision needs to be improved. The optimization plan for better sensor is presented. [ABSTRACT FROM AUTHOR]