Study of nanostructure formation processes on thin film surfaces irradiated with femtosecond laser pulses and development of its physical model

飞秒激光脉冲照射薄膜表面纳米结构形成过程的研究及其物理模型的建立

基本信息

批准号：
15360030
负责人：
MIYAZAKI Kenzo
金额：
$ 9.73万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

For the purposes of developing a new nanotechnology using femtosecond (fs) lasers, this research project was aiming at making clear experimental conditions and constructing a physical model for the periodic nanostructure formation and the selective change in bonding structure that we have recently found on hard thin films irradiated with fs laser pulses. The main results obtained are as follows.・The nanostructure size observed was λ/10〜λ/5 of the laser wavelength λ when fs laser pulses were irradiated on the thin films such as TiN and diamond-like carbon (DLC) at a low fluence near ablation threshold. We have shown that the nanostructure and its size could be controlled with the laser polarization, wavelength and fluence.・In addition, we have found that the DLC consisting of sp^3 and sp^2 can be modified into the conductive glassy carbon (GC) through the selective transition of sp^3 into sp^2 under almost the same experimental condition as for the nanostructure formation.・Reflectivity of DLC film surface was measured as a function of fluence and laser pulse shots. The results have shown that the reflectivity change is closely associated with the nanostructure formation, and that the superimposed laser shots and resulting incubation effect mainly contribute to the nanostructure formation.・The reflectivity of DLC was also measured using a pump and probe technique. The results have shown a characteristic reflectivity change due to the formation of a grating on the surface, where the selective change in the bonding structure from sp^3 to sp^2 induces a swelling of the film surface.・The measurements have demonstrated that the nanostructure formation on the DLC surface is certainly preceded by the change in the bonding structure.・On the basis of the experimental results obtained we have been developing a physical model for the nanostructure formation that relies on a localized field created in the interaction.

为了使用飞秒（fs）激光器的新纳米技术，该研究项目旨在明确实验条件并构建我们最近在硬薄膜上发现的周期性纳米结构形成和键合结构选择性变化的物理模型得到的主要结果如下。・当对薄膜照射飞秒激光脉冲时，观察到的纳米结构尺寸为激光波长λ的λ/10～λ/5。例如TiN和类金刚石碳（DLC）在接近烧蚀阈值的低注量下我们已经证明纳米结构及其尺寸可以通过激光偏振、波长和注量来控制。此外，我们还发现DLC。由sp^3和sp^2组成的物质可以在与纳米结构形成几乎相同的实验条件下通过sp^3选择性转变为sp^2而改性为导电玻璃碳（GC）。・DLC膜表面的反射率被测量为结果表明，反射率变化与纳米结构的形成密切相关，叠加的激光束和由此产生的孵化效应主要有助于纳米结构的形成。・还测量了 DLC 的反射率。使用泵和探针技术，结果显示由于表面上形成光栅而导致特征反射率变化，其中键合结构从 sp^3 到 sp^2 的选择性变化导致薄膜表面膨胀。・测量值有证明了 DLC 表面纳米结构的形成肯定先于键合结构的变化。・根据获得的实验结果，我们一直在开发纳米结构形成的物理模型，该模型依赖于相互作用中产生的局部场。

项目成果

期刊论文数量（94）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Materials control with high-intensity femtosecond laser pulses. I. Ultrafast alignment of molecules and its real-time detection

使用高强度飞秒激光脉冲进行材料控制。

DOI：
发表时间：
2005
期刊：
Proc.2nd In.Symp. on Sustainable Energy System (Kyoto Univ., Kyoto, 2005)
影响因子：
0
作者：
K.Miyazaki;et al.;M.Kaku et al.
通讯作者：
M.Kaku et al.

Coulomb explosion dynamics of nitrogen molecules with high-intensity femtosecond laser pulses

高强度飞秒激光脉冲氮分子库仑爆炸动力学

DOI：
发表时间：
2003
期刊：
Proceedings of The Third Asian Pacific Laser Symposium 68
影响因子：
0
作者：
K.Miyazaki;et al.
通讯作者：
et al.

Femtosecond-laser- induced alignment in Coulomb explosion of nitrogen molecules

氮分子库仑爆炸中的飞秒激光诱导排列

DOI：
发表时间：
2003
期刊：
Proc.CLEO/Pacific Rim 2003 (Nat.Taiwan Unv.Taipei, 2003)
影响因子：
0
作者：
N.Yasumaru;et al.;N.Yasumaru et al.;K.Miyazaki et al.;N.Yasumaru et al.;N.Yasumaru et al.;K.Miyazaki et al.;N.Yasumaru et al.;N.Yasumaru et al.;K.Miyazaki et al.
通讯作者：
K.Miyazaki et al.

N.Maekawa, W.Kobayashi, M.Kaku, K.Miyazaki: "Femtosecond-laser-induced structural change of diamond-like carbon film"Proc.of the 4th Asian pacific laser symposium. (in press). (2004)

N.Maekawa、W.Kobayashi、M.Kaku、K.Miyazaki：“飞秒激光诱导类金刚石碳膜结构变化”第四届亚太激光研讨会论文集。