AVS 60th International Symposium and Exhibition
    MEMS and NEMS Tuesday Sessions
       Session MN-TuP

Paper MN-TuP3
Micro Fabrication on Quartz Glass by Inductively Coupled Plasma-reactive Ion Etching and its Optical Application

Tuesday, October 29, 2013, 6:00 pm, Room Hall B

Session: MEMS and NEMS Poster Session
Presenter: Y.H. Tang, ITRC, NARL, Taiwan, Republic of China
Authors: Y.H. Tang, ITRC, NARL, Taiwan, Republic of China
Y.H. Lin, ITRC, NARL, Taiwan, Republic of China
P.-L. Chen, ITRC, NARL, Taiwan, Republic of China
M.-H. Shiao, ITRC, NARL, Taiwan, Republic of China
C.-N. Hsiao, ITRC, NARL, Taiwan, Republic of China
Correspondent: Click to Email
The etching characteristics of inductively coupled plasma-reactive ion etching (ICP-IRE) on the micro structure of quartz glass were investigated with a negative photoresist (KMPR 1050) etching mask material. We found that a nearly vertical side wall of the fabricated quartz glass profile with KMPR 1050 mask (negative photoresist). Detailed process characterization was performed by varying the process parameters which include ICP power, bias power and chamber pressure. In the case of KMPR mask, which has excellent material strength and good verticality, the etched micro structure exhibited a depth of 44.6 μm and vertical sidewall angle of 89° by means of ICP power 1500 W, bias power 120 W, and chamber pressure at 10 mTorr under a mixture gas of C4F8 and He at 12 and 84 sccm of flow rates, respectively. Moreover, the etching rate was controlled approximately at 0.249 μm per minute, the etching selectivity was more than a ratio of 1:2, and the roughness of etched surface was around 12.9 nm. Furthermore, the advantage of pattern transfer with high resolution and high accuracy has been demonstrated by fabricating subwavelength structure (SWS), achieving broadband antireflection (AR) and increasing the transmittance of incident light across the quartz glass. Consequently, smoothly tapered SWS surfaces with a width of 105 nm and a height of 190 nm could be produced on quartz wafer. This fabricated SWS decreased the surface reflectance to less than 6.75 % in the visible light spectrum.