Open AccessExperimental and FDTD study of silicon surface morphology induced by femtosecond laser irradiation at a high substrate temperature
Author(s) -
Guoliang Deng,
Guoying Feng,
Shouhuan Zhou
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.007818
Subject(s) - femtosecond , materials science , optics , laser , finite difference time domain method , silicon , substrate (aquarium) , surface roughness , irradiation , wavelength , surface finish , polarization (electrochemistry) , optoelectronics , composite material , chemistry , oceanography , physics , nuclear physics , geology
Substrate temperature is an important parameter for controlling the properties of femtosecond laser induced surface structures besides traditional ways. The morphology on silicon surface at different temperatures are studied experimentally. Compared to those formed at 300 K, smoother ripples, micro-grooves and nano/micro-holes are formed at 700 K. A two temperature model and FDTD method are used to discuss the temperature dependence of surface structures. The results show that the increased light absorption at elevated temperature leads to the reduction of surface roughness. The type-g feature in the FDTD-η map at 700 K, which corresponds to the energy deposition modulation parallel to the laser polarization with a periodicity bigger than the wavelength, is the origin of the formation of grooves. This work can benefit both surface structures based applications and the study of femtosecond laser-matter interactions.