Superhydrophobic antireflective silica films: fractal surfaces and laser-induced damage thresholds.
Several superhydrophobic antireflective silica films have been prepared by a solgel method that uses hexamethyl-disilizane (HMDS) as a modifier. In a high-power laser, laser-induced damage thresholds (LIDTs) of 23-30 J/cm2 were obtained at 1064-nm wavelength with 1-ns pulse duration. By atomic-force microscopy and optical microscopy, the fractal surfaces of films were studied, and multifractal spectra (MFSs) were calculated both before and after laser damage. The two-sided effect of HMDS on particle growth determined the surface fractal of a particle and the multifractal structure of a film's surface. The bigger deltaalpha was, both before and after laser damage, the lower the LIDT was. The effect of methyl groups should be included in the determination of the MFS of the LIDT.
Xu
Yao
Y
State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China. xuyaoc@yahoo.com.cn
Wu
Dong
D
Sun
Yu Han
YH
Huang
Zu Xing
ZX
Jiang
Xiao Dong
XD
Wei
Xiao Feng
XF
Li
Zhi Hong
ZH
Dong
Bao Zhong
BZ
Wu
Zhong Hua
ZH