In this paper, we present a new concept and fabrication of micro optical switch of which application is transmissive display devices. The micro optical switch consists of two parallel plate electrodes and is driven by electrostatic force. The first electrode is patterned on the glass substrate and the second electrode is disposed spaced apart from the first electrode. Each electrode has holes and the holes in each electrode do not overlap with one another. Light passes through the holes in the second electrode via the holes in the first electrode. All dimensions and fabrication process of the micro optical switch were designed to be compatible with Liquid Crystal Display (LCD) fabrication process. The size of the fabricated micro optical switch was 254μm × 254 μm. The micro optical switch was fabricated by surface micromachining. Aluminum was used as electrodes and patterned by plasma etching process. Photoresist was used as a sacrificial layer, which defined the gap between the two electrodes. Plasma ahsing was used to remove the sacrificial layer. Finally, anti-stiction layer was coated by Molecular Vapor Deposition (MVD) process. When voltage was applied, the second electrode moved down and contacted the first electrode. When voltage applying stopped, the second electrode returned to its original position. The voltage required to pull in the second electrode was below than 15 V. The sum of transition time, from on to off-state and from off to on-state, was below than 100 ㎲ and operating frequency was more than the 10 kHz.

Date Published: 13 March 2013
PDF: 6 pages
Proc. SPIE 8616, MOEMS and Miniaturized Systems XII, 86160J (13 March 2013); doi: 10.1117/12.2002262

Published in SPIE Proceedings Vol. 8616:
MOEMS and Miniaturized Systems XII
Wibool Piyawattanametha; Yong-Hwa Park, Editor(s)