Surface Micromachined Adjustable Micro-Concave Mirror for Bio-Detection Applications

Abstract

We present a bio-detection system integrated with an adjustable micro-concave mirror. The bio-detection system consists of an adjustable micro-concave mirror, micro flow cytometer chip and optical detection module. The adjustable micro-concave mirror can be fabricated with ease using commercially available MEMS foundry services (such as multiuser MEMS processes, MUMPs) and its curvature can be controlled utilizing thermal or electrical effects. Experimental results show that focal lengths of the micro-concave mirror ranging from 313.5 to 2275.0 𝜇m are achieved. The adjustable micro-concave mirror can be used to increase the efficiency of optical detection and provide a high signal-to-noise ratio. The developed micro-concave mirror is integrated with a micro flow cytometer for cell counting applications. Successful counting of fluorescent-labeled beads is demonstrated using the developed method.

Integrated Indium Micromirrors for Optofluidics

“…A research group of the National University of Formosa (Taiwan) has developed an adjustable micro-concave mirror to perform optical bio-detection applications [16]. This mirror is built in a polysilicon thin film over a silicon substrate, and has a thin gold film over it to increase reflectivity.…”

“…The diameter achieved for this mirror was 800µm. Source: [16] The micromirror was designed for bio-detection applications, especially for fluorescence. More than to bounce light beams, it was intended to focus them into one point.…”