光纤激光诱导背面干法刻蚀制备二元衍射光学元件

陈继民; 何超; 周伟平; 申雪飞

doi:doi:10.3788/ope.20122001.0031

光学精密工程, 2012, 20 (1): 31, 网络出版: 2012-02-14

光纤激光诱导背面干法刻蚀制备二元衍射光学元件

Fabrication of binary diffractive optical element by fiber laser induced backside dry etching

论文大纲

陈继民 ^*何超周伟平申雪飞

作者单位

北京工业大学激光工程研究院, 北京 100124

激光刻蚀微纳加工二元衍射光学元件能量密度阈值 laser etching micro/nano fabrication binary Diffractive Optical Element (DOE) energy threshold fluence

摘要

为了降低激光直接辐照透明介电材料的表面加工粗糙度和激光能量密度刻蚀阈值, 提高微光学元件的产出率, 介绍了一种用固体介质作吸收层, 激光直接作用在透明光学材料上进行微纳加工的激光诱导背面干法刻蚀工艺。首先, 选用95氧化铝陶瓷作固体材料辅助吸收层, 应用中心波长为1 064 nm的掺镱光纤激光器, 在3.2 mm厚的熔融石英玻璃表面刻蚀了亚微米尺度的二维周期性光栅结构。然后, 对刻蚀参数进行拟合并探讨了激光能量密度对刻蚀参数的影响。最后, 观察该二元光学元件的衍射花样图形并讨论其衍射特性。实验制备了槽深为4.2 μm, 槽底均方根粗糙度小于40 nm, 光栅常数为25 μm的二维微透射光栅, 其刻蚀阈值低于7.66 J/cm2。结果表明,应用该工艺制备二维透射光栅, 降低了激光刻蚀透明材料的密度阈值及加工结构的表面粗糙度。

Abstract

With the aim to lower the surface roughnesses of etched samples and the etching threshold fluence of a direct laser irradiation source and to raise the yield of micro-optical elements, a laser induced backside dry etching technique with the assistance of a solid medium as the absorbed layer was proposed to fabricate transparent dielectric materials by direct laser irradiation. By using an alumina ceramic wafer (Al2O3 in 95%, surface roughness less than 500 nm) as the absorber, a 2D transmittance grating in a micro size binary Diffractive Optical Element (DOE) was fabricated on the fused silica with a thickness of 3.2 mm by the 1 064 nm Ytterbium Doped Fiber (YDF) laser. And then, the etching parameter curves were fitted and the effect of laser energy density on the parameters was discussed. Finally, the diffraction patterns of micro structure were observed to examine the features of binary DOE. According to the measured results, the binary transmittance grating shows its grating constant in 25 μm,the depth of trench in 4.2 μm, and the RMS roughness of the trench bottom below 40 nm. Furthermore, the etching threshold influence is estimated below 7.66 J/cm2. These results are much lower than those of the etching without any absorbers.

参考文献

[1] 赫尔齐克. 微光学元件、系统和应用[M]. 北京: 国防工业出版社, 2002.

HERZIG H P. Micro-Optics Elements, Systems and Applications[M]. Beijing: China National Defense Industry Press,2001. (in Chinese)

[2] 佟军民, 胡松, 李爱敏,等. 衍射光学元件在无掩模光刻中的应用[J]. 微细加工技术, 2006, 10(5): 18-23.

TONG J M, HU S, LI A M, et al.. Application of diffractive optical elements in maskless lithography[J]. Microfabrication Technology, 2006,10(5): 18-23. (in Chinese)

[3] 仇中军, 周立波, 房丰洲. 石英玻璃的化学机械磨削加工[J]. 光学精密工程, 2010, 18(7): 1554-1561.

QIU ZH J, ZHOU L B, FANG F ZH, et al.. Chemical mechanical grinding for quartz glass[J]. Opt. Precision Eng., 2010,18(7): 1554-1561. (in Chinese)

[4] 沈易, 吴翌旭, 邢燕冰,等. 多光束无掩模光刻系统[J]. 应用光学, 2010,31(4): 537-539.

SHEN Y, WU Y X, XING Y B, et al.. Multi-beam maskless lithograph system[J]. Journal of Applied Optics,2010,31(4): 537-539. (in Chinese)

[5] EHRHARDT M, RACIUKAITIS G, GECYS P, et al.. Laser-induced backside wet etching of fluoride and sapphire using picosecond laser pulses[J]. Appl. Phys. A, 2010,101: 399-404.

[6] ZIMMER K,BHME R, EHRHARDT M, et al.. Mechanism of backside etching of transparent materials with nanosecond UV-lasers [J]. Appl. Phys. A, 2010,101: 405-410.

[7] BHME R, PISSADAKIS S, EHRHARDT M, et al.. Backside etching of fused silica with ultra-short laser pulses at the interface to absorbing liquid [J]. Journal of Physics: Conference Series, 2007,59: 173-176.

[8] HOPP B, VASS C, SMAUSZ T. Laser induced backside dry etching of transparent materials [J]. Applied Surface Science, 2007,253: 7922-7925.

[9] ZIMMER K, BHME R, VASS C, et al.. Time-resolved measurements during backside dry etching of fused silica [J]. Applied Surface Science, 2009(25): 9617-9621.

[10] ZIMMER K,BHME R, RAUSCHENBACH B. Laser etching of fused silica using an adsorbed toluene layer [J]. Appl. Phys. A, 2004,79: 1883-1885.

[11] SMAUSZ T, CSIZMADIA T, KRESZ N, et al.. Influence on the laser induced backside dry etching of thickness and material of the absorber, laser spot size and multipulse irradiation [J]. Applied Surface Science, 2007,254: 1091-1095.

[12] YENA M H, HUANG C W, HSU W C. Crack-free micromachining on glass substrates by visible LIBWE using liquid metallic absorbers [J]. Applied Surface Science, 2010,257: 87-92.

[13] EHRHARDT M, RACIUKAITIS G, GECYS P, et al.. Microstructuring of fused silica by laser-induced backside wet etching using picosecond laser pulses [J]. Applied Surface Science, 2010,256: 7222-7227.

[14] LEE T, JANG D, AHN D, et al.. Effect of liquid environment on laser-induced backside wet etching of fused silica [J]. J. Appl. Phys., 2010,107: 033-112.

[15] ZIMMER K, BHME R, RUTHE D, et al.. Backside laser etching of fused silica using liquid gallium[J]. Appl. Phys. A, 2006,84: 455-458.

[16] BANKS D P, KAUR K S, EASON R W. Etching and forward transfer of fused silica in solid-phase by femtosecondlaser-induced solid etching (LISE)[J]. Applied Surface Science, 2009,255: 8343-8351.

[17] HOPO B, SMAUSZ T, VASS C, et al.. Laser-induced backside dry and wet etching of transparent materials using solid and molten tin as absorbers [J]. Appl. Phys. A, 2009,94: 899-904.

[18] 单明广, 钟志, 郭黎利, 等. 用于无模光刻的连续浮雕谐衍射透镜阵列设计[J]. 光学精密工程, 2010,18(1): 9-14.

SHAN M G, ZHONG ZH, GUO L L. Design of continuous-relief harmonic diffractive microlens array for maskless lithography[J]. Opt. Precision Eng., 2010,18(1): 9-14. (in Chinese)

[19] HUANG Z Q, HONG M H, DO T B M, et al.. Laser etching of glass substrates by 1 064 nm laser irradiation [J]. Appl. Phys. A, 2008,93: 159-163.

[20] BONSE J, WROBEL J M, KRGER J, et al.. Ultrashort-pulse laser ablation of indium phosphide in air [J]. Applied Physics A-Materials Science & Processing, 2001,72: 89-92.

陈继民, 何超, 周伟平, 申雪飞. 光纤激光诱导背面干法刻蚀制备二元衍射光学元件[J]. 光学精密工程, 2012, 20(1): 31. CHEN Ji-min, HE Chao, ZHOU Wei-ping, SHEN Xue-fei. Fabrication of binary diffractive optical element by fiber laser induced backside dry etching[J]. Optics and Precision Engineering, 2012, 20(1): 31.

光纤激光诱导背面干法刻蚀制备二元衍射光学元件

关于本站 Cookie 的使用提示

全站搜索

光纤激光诱导背面干法刻蚀制备二元衍射光学元件

相关论文

相关资讯

关于本站 Cookie 的使用提示

全站搜索