Te-free SbBi thin film as a laser heat-mode photoresist

A Te-free binary phase change material Sb Bi is proposed as a new inorganic photoresist for heat-mode lithography. It shows good film-forming ability(surface roughness <1 nm), low threshold power for crystallization(2 m W), and high etching selectivity(15:1). Line-type, dot-type, and complex pattern structures with the smallest feature size of 275 nm are fabricated on Sb Bi thin films using a 405 nm diode laser direct writing system. In addition, the excellent grating structures with a period of 0.8 μm demonstrate that thermal interference does not affect the adjacent microstructures obviously. These results indicate that Sb Bi is a promising laser heat-mode resist material for micro/nanostructure fabrication.

MSCT在鼻咽癌颅底骨侵犯的应用价值

目的分析鼻咽癌颅底侵犯MSCT诊断价值。方法分析经病理证实28例鼻咽癌患者MSCT影像资料,比较多平面重组(MPR)与横断面图像对颅底侵犯的检出情况。结果 MSCT多平面重组(MPR)显示25例颅底侵犯,横断面图像显示19例。横断面表现主要为骨质破坏和颅底孔道增宽,而MPR除骨质改变外,还能清楚显示颅底侵犯的范围。结论 MSCT可精确显示鼻咽癌颅内侵犯的部位、途径及范围,有助于临床分期及指导放疗野的设置。

Sb_(80)Bi_(20)相变薄膜的非线性光学响应

利用磁控溅射法在K9玻璃基底上制备了SiN/Sb80Bi20/SiN相变薄膜结构,并利用连续He-Ne激光共焦Z-扫描技术同时测量了在激光作用下透射和反射非线性光学响应。实验结果表明,相变膜在激光焦点处的反射和透射信号由于薄膜的相变表现为非线性响应特性。薄膜在焦点处的透射信号强度随着扫描激光功率的增强逐渐增大直至饱和。这是由于在激光的作用下形成了相变微区,随着扫描功率的增加,相变区域逐渐变大引起的。对不同功率激光扫描后的样品进行了低于相变阈值的重复扫描实验,结果表明,相变区域具有较高的光热稳定性,说明BiSb相变薄膜具有相变数据存储潜在应用价值。