光学精密工程2012，Vol.20Issue(1)：31-37,7.DOI:10.3788/OPE.20122001.0031
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
摘要
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 (A12O3 in 95%, surface roughness less than 500 nm) as the absorber, a 2D transmit-tance 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 below40 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.关键词
激光刻蚀/微纳加工/二元衍射光学元件/能量密度阈值Key words
laser etching/ micro/nano fabrication/ binary Diffractive Optical Element (DOE)/ energy threshold fluence分类
信息技术与安全科学引用本文复制引用
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):31-37,7.基金项目
北京市教委重点项目(No.KZ20091005006) （No.KZ20091005006）
