Porous silicon micro-resonator implemented by standard photolithography process for sensing application

Abstract

International audienceA micro-resonator based on porous silicon ridge waveguides is implemented by a large scale standard photolithography process to obtain a low cost and sensitive sensor based on volume detection principle instead of the evanescent one usually used. The porous nature of the ridge waveguides allows the target molecules to be infiltrated in the core and to be detected by direct interaction with the propagated light. Racetrack resonator with radius of 100 µm and a coupling length of 70 µm is optically characterized for the volume detection of different concentrations of glucose. A high sensitivity of 560 nm/RIU is reached with only one micro-resonator and a limit of detection of 8.10-5 RIU, equivalent to a glucose concentration of 0.7 g/L, is obtained

Quantification of porosity in extensively nanoporous thin films in contact with gases and liquids

“…The electrical properties of thin porous layers possess an advantage in fabrication of ultralow- k dielectric films for minimization of RC delay in nano-integrated circuits, while the low thermal conductivity of such films can be utilized for engineering of high-performance thermally insulating barriers 4 . Thin mesoporous coatings characterized by low refractive index are highly desirable for optical applications, such as antireflection coatings 5 and optical microresonators 6 . The physical and morphological properties of nanoporous and mesoporous layers are strongly linked to materials’ porosity (defined as the ratio of the void volume to the total volume of the layer).…”

Submicron gap reduction of micro-resonator based on porous silica ridge waveguides manufactured by standard photolithographic process

“…Thus, with regard to all these aspects, an initial porosity of 50% which gives after oxidation a porosity of 20%, has been chosen. This porosity allows to obtain pore diameters in an estimated range [10 -30 nm] that is sufficient for detection applications that we have already conducted for example in reference [31,32].…”

Nanosilicon-Based Composites for (Bio)sensing Applications: Current Status, Advantages, and Perspectives

“…Optical transmittance of PSi microring resonators and microcavities was used as the signal for sensor and biosensor applications [101,102,103,104]. Weiss et al reported on 10 μm and 25 μm microring waveguides for nucleic acid (PNA) detection via transmittance measurements.…”