@article{oai:miyazaki-u.repo.nii.ac.jp:00002981,
 author = {水野, 俊男 and 向本, 徹 and Yokotani, Atsushi and 横谷, 篤至 and 川原, 公介 and 二宮, 孝文 and 沢田, 博司 and 黒澤, 宏 and Mizuno, Toshio and Mukumoto, Toru and Kawahara, Kosuke and Ninomiya, Takahumi and Sawada, Hiroshi and Kurosawa, Kou},
 journal = {宮崎大学工学部紀要, Memoirs of Faculty of Engineering, University of Miyazaki},
 month = {Oct},
 note = {Silicon is the most basic material in the semiconductor industry, because it is used as a substrate of the integrated circuits (ICs). The silicon substrates are planed to reduce the thickness as thin as 50 μm for the ICs of
the next generation. Since mechanical strength ofsuch a thin substrate is extremely weak, it is very difficult to cut by the convectional mechanical dicing technique. Therefore new techniques using lasers in which
non-contact process is expected have been tried to develop by many researchers. Especially, it is said that a femtosecond laser can do processing with a little thermal effect compared with the case using the nanosecond laser. However, it has not been completed to eliminate the thennal effects, even if use with femtosecond laser.
Then to find out the reason, we have tried to observe the process that the drilled hole is formed with a high speed imaging technique using ICCD camera. A regenerative amplified Ti:sapphire laser (E = 30 ~ 500 μJ/pulse, r= 200 fs,λ= 780 nm, f= 10 Hz) was used and focused onto a 50 μm-thick silicon sample. The
gate ofthe ICCD camera was set at 5 ns. First, we investigated the dependence of laser energy on the speed of the fonnation of the drilled hole. As a result, it was found that the larger the energy, the slower the speed of the
formation. Even if the smaller energy density was used, very slow speed of formation and much larger thermal effects are observed when the defocused condition was used. So we can say that the degree of the thennal
effects is not simply related to the energy density of the laser but strongly related to the speed of the formation, which can be measured by the ICCD camera. The similar tendency was also obtained for other materials, which are important for the fabrication of ICs (Al, Cu, SiO2 and acrylic resin).},
 pages = {93--99},
 title = {フェムト秒レーザーを用いた半導体関連材料の加工と特性の評価},
 volume = {33},
 year = {2004},
 yomi = {ミズノ, トシオ and ムクモト, トオル and ヨコタニ, アツシ and カワハラ, コウスケ and ニノミヤ, タカフミ and サワダ, ヒロシ and クロサワ, コウ}
}