Large area and broadband semi-reflective Bragg mirror membrane manufactured by PECVD
Abstract
Non-absorbing beam splitters integrated on silicon are desirable for various micro-opto electro mechanical systems (MOEMS) devices. In this paper, we demonstrate the manufacturing with a 100% yield of dielectric membranes having a diameter up to 5.9 mm and an approximately 50% reflectivity in the 570-900 nm wavelength range. The membranes are made from a stack of up to 12 alternating SiNx and SiO2 plasma enhanced chemical vapor deposition (PECVD) films deposited and annealed on silicon. Backside micromachining of the silicon wafer by deep reactive ion etching followed by XeF2 etching is used to release the membranes. Annealing effects on stress variation and hydrogen bonding in PECVD single films and multilayers were investigated in detail to get a multilayer stack with controlled tensile stress. Optical measurements of the reflectivity, flatness and vibrations of these membranes show that they are suitable for use in MOEMS devices working in the visible-near infrared range.
- Publication:
-
Journal of Micromechanics and Microengineering
- Pub Date:
- July 2013
- DOI:
- 10.1088/0960-1317/23/7/074005
- Bibcode:
- 2013JMiMi..23g4005B