Investigation of Wet Etching with Surfactant Applied on the Releasing Process of Devices Fabricated by Surface Micro Machining

Chien-Chung Tsai ； Y-Cheng Huang ； Chia-Jung Lee ； Chia-Ching Chang Chien

《淡江理工學刊》 10卷2期 (2007/06) Pp. 155-158

https://doi.org/10.6180/jase.2007.10.2.11

並列摘要

Investigation of surfactant applied on wet etching for releasing the micro optical devices with Micro Array Thermal Actuator, MATA, fabricated by Surface Micromachining common process is proposed in this paper. BOE (buffered oxide etch), concentrated HF (49%), concentrated HF (49%) with 10% surfactant are adopted as the etchants for releasing the micro optical devices in experiment, respectively. Low Temperature Oxide, LTO, is a sacrificial layer material and the etching phenomena will be demonstrated by the three different etchants during the releasing process. The experimental results exhibit Poly-Si is seriously damaged and geometrical dimensions of the micro structure are reduction by BOE (6:1) compared with the original design. On the other hand, the geometrical features of the micro devices are consistency with the original design and successfully released by concentrated HF (49%) etching. However, there are some residual LTO on the surface of Poly 1 layer during the period of concentrated HF (49%) etching process. Nevertheless, the residual LTO on Poly 1 layer surface is significantly improved by the concentrated HF (49%) with 10% surfactant. Finally, the micro optical devices fabricated by SMart common process are successfully released by the concentrated HF (49%) with 10% surfactant and the surfaces of devices are relatively smooth.

並列關鍵字

Micro-optics ； Surface Micromachining ； Wet Etching ； Sacrificial Layer