UC Santa Cruz

Micro-Electro-Mechanical Systems (MEMS) allow scaling down and integration of conventional scientific instrumentation. In particular, advancements in fabrication have made possible the creation of small, precise and inexpensive versions of optical components and systems.

Optical components for the use in mid-wave infrared (MWIR) range, 3-5 m wavelength, are of particular interest for their ability to detect various organic chemical compounds and to determine the temperature of objects based on their radiation emission. High sensitivity, but low spectral resolution of optical detectors in the MWIR region requires addition of optical filters to provide spectral information.

In this thesis we describe the design, fabrication, and testing of a MEMS-based optical filter that combines a Fabry-Perot interferometer with dielectric Bragg reflectors, using magnetic actuation.

The research started with identification of the problem, complete literature search to identify the existing solutions. A novel design for an improved optical filter was proposed. Optical and mechanical models were created, and materials were chosen that correlated to the optical model. Fabrication flow was developed for robust and wafer-scale process that achieves high yield and improves optical performance. Three iterations of fabrication cycle resulted in improvement of optical characteristics of the devices by three orders of magnitude.

Mechanical method of magnetic actuation was developed that allows precise movement across the entire range of MWIR. Optical results from the first device were shown to correlate with mechanical and optical models.