Matteo d’Angelo, Dario Crimella, Carmen Galassi, Nora Lecis, Ali Gökhan Demir
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引用次数: 0
Abstract
Interest towards fabrication and post-processing of thermoelectric micro-sized devices has increased in recent years. The coupling of inexpensive deposition technologies and fast laser treatments on “as-deposited” films is an attractive solution for industrial scalability. In this work, we propose an approach never reported before in literature: the utilization of a ns-pulsed active fibre laser to directly densify p-type bismuth telluride-based thick films deposited on silicon. A feasibility study was conducted on the material to determine optimal laser parameters: the treated products were characterized, and it was concluded that a value of laser fluence as low as 4.5 mJ cm−2 is sufficient for densification. The material resulted cracked after the laser treatment, and it was demonstrated by SEM and profilometric analyses that shrinking occurs and sintering necks are formed; further, the arising of second phases after annealing was excluded by means of XRD analysis. Envisioning an industrial large area process with linear diode arrays source, a prediction of the laser power requirements to irradiate 1 mm2 films in selected conditions is presented. More extensive studies will be performed to determine a narrower parameters window and determine a relationship between the film thickness and laser parameters for future applications to as-deposited films.
期刊介绍:
Optik publishes articles on all subjects related to light and electron optics and offers a survey on the state of research and technical development within the following fields:
Optics:
-Optics design, geometrical and beam optics, wave optics-
Optical and micro-optical components, diffractive optics, devices and systems-
Photoelectric and optoelectronic devices-
Optical properties of materials, nonlinear optics, wave propagation and transmission in homogeneous and inhomogeneous materials-
Information optics, image formation and processing, holographic techniques, microscopes and spectrometer techniques, and image analysis-
Optical testing and measuring techniques-
Optical communication and computing-
Physiological optics-
As well as other related topics.