Characterization of Surface Plasmons on Metal-oxide-semiconductor Structures

Sensor properties and surface characterization of aluminum-deposited SPR optical fibers

“…They suggested the necessity of the inclusion of a thin (2.5 nm) cermet layer at the Al-Al 2 O 3 (3 nm) interface for modeling the response. The inclusion of the cermet layer is physically taken to indicate the presence of surface roughness and also surface contamination [10]. McNeill et al [11] and Cairns et al [12] characterized the surfaces of deposited Al films with thicknesses of about 20 nm for the study of laser ablation by SPR.…”

“…Though the peak width depends on both the film thickness and the refractivity of a sample, the half (1 • ) of the FWHM at the refractivities of 1.327 and 1.373 was used for the numerical calculations of the response curves of the Al-deposited optical fiber sensors for simplicity as discussed below. Tamm et al [10] measured the SPR reflection spectra of the Al electrodes of Si-SiO 2 -Al structures with thicknesses of 20-25 nm by use of the Otto configuration. They suggested the necessity of the inclusion of a thin (2.5 nm) cermet layer at the Al-Al 2 O 3 (3 nm) interface for modeling the response.…”

“…where k 0 is the dispersion relation of SPR of a metal-vacuum interface in a one-sharp boundary model, k r is the perturbation to k 0 due to the finite physical volume of the metal, k t is the modification to k 0 due to the transducing (oxide) layer, ε s is the dielectric constant of a sample approximated by ε s = n s 2 (n s is the refractivity of a sample), and ε m (−37.0) and ε t (3.0) are the real parts of the dielectric constants of Al and Al 2 O 3 at 632.8 nm, respectively [10], and d m and d t are the film thicknesses of Al and Al 2 O 3 , respectively. When Eqs.…”

“…The SPR reflection spectra of Al films have been measured in both the Otto configuration [8][9][10] and the Kretschmann configuration [11][12][13]. The optical constants of deposited Al films [8], the reflection properties of a MgF 2 -coated Al mirror [9], the influence of surface oxide layers of Si-SiO 2 -Al structures on SPR [10], the thicknesses of the oxide layers grown on deposited Al films on silica prisms [11,12], and the conditions for light-induced excitation of SPR at an Al-liquid interface [13] have been investigated. Though these investigations give important information on the SPR phenomenon of Al films, more investigations are necessary to understand the properties of Al films as an SPR sensor element.…”

Signal enhancement of protein binding by electrodeposited gold nanostructures for applications in Kretschmann-type SPR sensors

“…1 Therefore, SPR sensors are widely used in biochemistry, clinical diagnosis, food analysis, and environmental biology. 2,3 Several types of sensing techniques using SPR phenomena have been developed, including the Kretschmann, 4 Otto, 5 and optical fibre types 6 and localized surface plasmon resonance (LSPR) sensing. 7 Among these techniques, Kretschmann-type SPR sensing has been the most commonly used because of the simple setup for chip fabrication and sensing; it is employed in commercially available equipment from various companies, such as Biacore.…”