TY - GEN
T1 - Investigation on micro-machining characteristics and phenomenon of semiconductor materials by harmonics of Nd:YAG laser
AU - Hirano, Takayuki
AU - Okamoto, Yasuhiro
AU - Okada, Akira
AU - Uno, Yoshiyuki
AU - Sakagawa, Tomokazu
AU - Nakashiba, Shin Ichi
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2012
Y1 - 2012
N2 - Precision micro-machining without crack and heat affected zones is required in order to use high-performance materials such as silicon and silicon carbide, and it is expected that the higher harmonics of the Nd:YAG laser can perform precision micro-machining due to its high photon energy. However, even by using the harmonics of the Nd:YAG laser, a heat affected zone is inevitable due to the plasma generation. In order to reduce the influence of plasma on the processing results, it is important to understand the generation mechanism of plasma. Therefore, the laser induced plasma in micro-drilling of silicon carbide was observed by a high-speed shutter camera, and the influence of laser wavelength and surrounding conditions on the machining characteristics were experimentally investigated. The removal depth increased with decreasing wavelength and the surrounding gas pressure. The surface integrity was improved by the combination of shorter wavelength and reduced pressure conditions. The behavior of laser induced plasma was different from the wavelength of the laser beam and the surrounding gas pressure. Under atmospheric pressure conditions, the plasma grew greatly and affected the wider surface around the drilled hole with increasing wavelength. Under reduced pressure conditions, there was little difference in plasma size by wavelength, and the affected zone around the drilled hole became relatively smaller. It became clear that a low surrounding gas pressure and shorter wavelength were important to obtain better surface integrity and highly efficient processing.
AB - Precision micro-machining without crack and heat affected zones is required in order to use high-performance materials such as silicon and silicon carbide, and it is expected that the higher harmonics of the Nd:YAG laser can perform precision micro-machining due to its high photon energy. However, even by using the harmonics of the Nd:YAG laser, a heat affected zone is inevitable due to the plasma generation. In order to reduce the influence of plasma on the processing results, it is important to understand the generation mechanism of plasma. Therefore, the laser induced plasma in micro-drilling of silicon carbide was observed by a high-speed shutter camera, and the influence of laser wavelength and surrounding conditions on the machining characteristics were experimentally investigated. The removal depth increased with decreasing wavelength and the surrounding gas pressure. The surface integrity was improved by the combination of shorter wavelength and reduced pressure conditions. The behavior of laser induced plasma was different from the wavelength of the laser beam and the surrounding gas pressure. Under atmospheric pressure conditions, the plasma grew greatly and affected the wider surface around the drilled hole with increasing wavelength. Under reduced pressure conditions, there was little difference in plasma size by wavelength, and the affected zone around the drilled hole became relatively smaller. It became clear that a low surrounding gas pressure and shorter wavelength were important to obtain better surface integrity and highly efficient processing.
KW - Laser
KW - Plasma behavior
KW - Silicon carbide
KW - Surrounding gas pressure
KW - Wavelength
UR - http://www.scopus.com/inward/record.url?scp=84862729063&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84862729063&partnerID=8YFLogxK
U2 - 10.4028/www.scientific.net/KEM.516.36
DO - 10.4028/www.scientific.net/KEM.516.36
M3 - Conference contribution
AN - SCOPUS:84862729063
SN - 9783037854280
T3 - Key Engineering Materials
SP - 36
EP - 41
BT - Proceedings of Precision Engineering and Nanotechnology
PB - Trans Tech Publications Ltd
T2 - 4th International Conference of Asian Society for Precision Engineering and Nanotechnology, ASPEN 2011
Y2 - 16 November 2011 through 18 November 2011
ER -