TY - JOUR
T1 - Planar-Waveguide-LMR-Based Sensors
T2 - Engineering the Depth of Characteristic Curves
AU - Shrivastav, Anand M.
AU - Del Villar, Ignacio
AU - Ascorbe, Joaquin
AU - Corres, Jesus M.
AU - Matias, Ignacio R.
N1 - Funding Information:
This work was supported in part by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant 101034288 and in part by Campus Iberus Universities.
Publisher Copyright:
IEEE
PY - 2023/8/1
Y1 - 2023/8/1
N2 - Lossy mode resonance (LMR)-based sensors have been proven as one of the exponentially growing research fields since the last decade. These sensors have demonstrated their capabilities in the detection of several physical, chemical, and biological entities, such as refractive index, humidity, gases, enzymes, etc. Conventionally, LMR-based sensors are developed using optical fiber as the sensing platform, but to increase the broad range of applications and better tenability, planar waveguide substrates for LMR realization have been introduced in the last few years. This provides a greater degree of freedom for the sensor design such as tunability in substrate thickness, material, and better surface immobilization. The current study focuses on evaluating the effect of substrate thickness on LMR-based optical sensors to achieve higher sensing performance. For experiments, 150-μm-thick glass coverslips are used as the thin planer substrate, which is then coated with a few nanometers thick LMR-supported SnO2 layer using the dc sputtering method. Furthermore, to monitor the effect of the changing substrate thickness, the width of the glass coverslip is reduced through the chemical etching process using the 40% HF solution, and simultaneously, the changes in LMR spectra are analyzed. The study shows that the depth of LMR curves strongly depend on the thickness of the waveguide providing LMRs with lower substrate thickness possesses higher depth. Greater depth in LMR curves is a crucial factor in identifying the minimum transmission wavelength of resonance, making it easier to track and detect the targeted parameter. This characteristic greatly enhances the applicability of LMR-based sensors in industrial applications.
AB - Lossy mode resonance (LMR)-based sensors have been proven as one of the exponentially growing research fields since the last decade. These sensors have demonstrated their capabilities in the detection of several physical, chemical, and biological entities, such as refractive index, humidity, gases, enzymes, etc. Conventionally, LMR-based sensors are developed using optical fiber as the sensing platform, but to increase the broad range of applications and better tenability, planar waveguide substrates for LMR realization have been introduced in the last few years. This provides a greater degree of freedom for the sensor design such as tunability in substrate thickness, material, and better surface immobilization. The current study focuses on evaluating the effect of substrate thickness on LMR-based optical sensors to achieve higher sensing performance. For experiments, 150-μm-thick glass coverslips are used as the thin planer substrate, which is then coated with a few nanometers thick LMR-supported SnO2 layer using the dc sputtering method. Furthermore, to monitor the effect of the changing substrate thickness, the width of the glass coverslip is reduced through the chemical etching process using the 40% HF solution, and simultaneously, the changes in LMR spectra are analyzed. The study shows that the depth of LMR curves strongly depend on the thickness of the waveguide providing LMRs with lower substrate thickness possesses higher depth. Greater depth in LMR curves is a crucial factor in identifying the minimum transmission wavelength of resonance, making it easier to track and detect the targeted parameter. This characteristic greatly enhances the applicability of LMR-based sensors in industrial applications.
KW - Sensor integration
KW - full-width half-minimum (FWHM)
KW - lossy mode resonance (LMR)
KW - optical sensors
KW - waveguide
UR - http://www.scopus.com/inward/record.url?scp=85165899459&partnerID=8YFLogxK
U2 - 10.1109/LSENS.2023.3297314
DO - 10.1109/LSENS.2023.3297314
M3 - Article
AN - SCOPUS:85165899459
SN - 2475-1472
VL - 7
JO - IEEE Sensors Letters
JF - IEEE Sensors Letters
IS - 8
M1 - 5000304
ER -