Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)
- Volume 11 Issue 4
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- Pages.528-536
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- 1999
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- 1229-6422(pISSN)
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- 2465-7611(eISSN)
Effects of transient thermo reflectance on the thermal responses of metal thin film exposed to ultrashort laser heating
극초단 펄스레이저 광이 입사된 금속박막의 열적반응 중 비정상반사율의 영향
Abstract
This work studies the effects of transient reflectance on the thermal responses of a metal(gold) thin-film during ultrashort laser heating. The heating process is calculated using the conventional conduction model (parabolic one-step: POS), parabolic two-step model (PTS) with and without variable properties, hyperbolic two-step model (HTS). Results from the HTS model are very similar to those from the PTS model, since the laser heating time in this study is greater than the electron relaxation time. PTS model with variable properties, however, results in totally different temperature profiles compared to those from POS models or calculation with constant properties. Transient reflectances are estimated from electron temperature distributions and based on the linear relationship between the electron temperature and complex dielectric constants. Reflectance of the front surface can be changed with respect to dielectric constants, while those of the rear surface remain unchanged.
Keywords
- Metal thin-film;
- Ultrashort pulse laser heating;
- Microscale heat transfer;
- Transient thermoreflectance;
- Complex dielectric constants
- 금속박막;
- 극초단 펄스레이저 가열;
- 미세열전달;
- 비정상 반사율;
- 복소유전상수;