Current status and outlook for silicon-based optical biosensors

The importance of silicon photonic devices extends beyond passive structures for light guiding and light emission. Nano- and microstructured silicon photonic devices have emerged as viable gas, chemical, and biological sensors. The advantages of these silicon-based optical biosensors for high sensitivity detection include a low analyte volume requirement, reduced size, and compatibility with existing CMOS technology. Several advances in ring resonators, waveguides, and various porous silicon photonic structures for biosensing applications will be reviewed.