An integrated Mach–Zehnder interferometric biosensor with a silicon oxynitride waveguide by plasma-enhanced chemical vapor deposition

Last Advances in Silicon-Based Optical Biosensors

“…The trend over last few years has been to improve sensitivity, integration or cost-efficiency. In order to improve cost-efficiency of the fabrication process using Si-technology, alternatives to Si 3 N 4 as a core layer have been developed such as SiO x N y , deposited using plasma-enhanced chemical vapour deposition (PECVD) [ 26 , 27 ]. Regarding integration, due to the low-cost of the light sources, photodetectors, and other optical components for visible wavelengths, make it easier to implement a portable LOC device.…”

Functionalization of silicon dioxide and silicon nitride surfaces with aminosilanes for optical biosensing applications

“…Thus, the conditions of both the silane deposition and curing vary greatly from one report to another. For example, modification with APTES has been performed using 0.1% solution in dry toluene for 1 hr followed by heating at 110°C for 2 hr (Brosinger et al, 1997), 10% aqueous solution, pH 3.45, at 80°C for 2 hr and curing at 100°C for 1 hr (Brandenburg, Krauter, Kunzel, Stefan, & Schulte, 2000; Jiang et al, 2014), 2% solution in a mixture of 95%/5% (v/v) ethanol/H 2 O for 2 hr and heating at 120°C for 15 min (Liu, Kim, Gu, Kee, & Park, 2014; Liu, Lim, Soo, Park, & Shin, 2015; Liu et al, 2013), 10% solution in ethanol and drying at room temperature for 2 hr (Choo et al, 2014), or 0.5% aqueous solution for 2 min and curing at 120°C for 20 min (Angelopoulou et al, 2015; Psarouli et al, 2015). APTES has been also deposited from vapours in a vacuum chamber (Densmore et al, 2008, 2009).…”

A plasmonic refractive index sensor with an ultrabroad dynamic sensing range

“…Many improved and miniatured SPR sensors have been accomplished using optical fibers 6 – 8 , varying microcavities coupled with metal-insulator-metal (MIM) waveguides 9 , 10 , Mach-Zehnder interferometric biosensor 11 , metallic nanoparticles 12 – 14 or plasmonic metamaterials 15 – 17 . However, these state-of-the-art SPR RI sensors with promising sensing performance determined by the derivative of the monitored SPR parameters (e.g., resonant angular, resonant wavelength, intensity near the resonance) are only operated under a narrow detection range for RI changes.…”