Optical properties of sputtered fluorinated ethylene propylene and its application to surface-plasmon resonance sensor fabrication

Keathley, Phillip D.; Hastings, J. T.

doi:10.1116/1.3013368

Cited by 6 publications

(12 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In these implementations, the refractive index of the buffer layer has to match to that of aqueous samples ͑close to 1.33 at the wavelength of = 632.8 nm͒ in order to achieve a symmetrical refractive index structure needed for the excitation of LRSPs. Up to date, fluoropolymers deposited by spincoating 10,14 or sputtering 17 and low refractive index dielectric layers such as aluminum fluoride 18 or magnesium fluoride 14 prepared by thermal evaporation were used for the construction of layer systems supporting LRSPs. In this contribution, we investigate thin gold films deposited on a Cytop fluoropolymer for the excitation of LRSPs on the surface of a SFPS biosensor.…”

Section: Introductionmentioning

confidence: 99%

Optimization of layer structure supporting long range surface plasmons for surface plasmon-enhanced fluorescence spectroscopy biosensors

Huang

Dostálek

Knoll

2010

Journal of Vacuum Science &Amp; Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phen

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

Optimization of layer structure supporting long range surface plasmons for surface plasmon-enhanced fluorescence spectroscopy biosensors

Huang

Dostálek

Knoll

2010

Journal of Vacuum Science &Amp; Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phen

View full text Add to dashboard Cite

show abstract

“…The smaller refractive index of CAT-CVD films indicates a presence of air in the films. The authors of [54] obtained thin films of Teflon FEP with a somewhat higher refractive index than that of the sputtered target material. This increased value of the refractive index could be caused by dense packing in the film or by inclusion into the film of impurities such as carbonized clusters and other chemical groups synthesized in the plasma at a comparatively high pressure.…”

Section: Discussionmentioning

confidence: 99%

Fluoropolymer Film Formation by Electron Activated Vacuum Deposition

et al. 2021

View full text Add to dashboard Cite

Polytetrafluoroethylene (PTFE), polyhexafluoropropylene (PHFP) and polychlorotrifluoroethylene (PCTFE) were heated to their decomposition temperature in a high vacuum. The emitted fragments passed an electron cloud, condensed on a substrate and formed fluoropolymer film. Growth rate of PTFE and PHFP films increased up to a factor five in the presence of the electron cloud. Mass spectrometry revealed changes in the mass spectra of fragments generated by thermal decomposition only and formed under electron activation. The observed changes were different for each fluoropolymer. Infrared spectroscopy (IRS) showed that the structure of the films was close to the structure of the bulk polymers. Atomic force microscopy (AFM) has revealed different morphologies of PTFE, PHFP and PCTFE films, suggesting a Volmer–Weber growth mechanism for PTFE and PHFP but a Frank-van der Merwe one for PCTFE. All films were smooth at nanoscale and transparent from ultraviolet to near-infrared region. Additional radio frequency (RF) plasma ignited in the emitted fragments at a low pressure increased mechanical characteristics of the films without losing their optical transparency and smoothness.

show abstract

“…It is an ideal cladding material for both PC and PSU core fibers due to: firstly, FEP is very soft (Young's modulus of FEP is 0.48 GPa [28], compared to that of silica is 70 GPa [29]), and therefore can highly increase the overall flexibility of the optical waveguide, a crucial property to achieve long-term deep tissue neuromodulation and minimize the foreign body response (FBR) [30]. Secondly, FEP has one the lowest RI within all the thermoplastics (1.34@630 nm [31]). The large RI difference between the core materials (PC, PSU) and the cladding material FEP leads to the UHNA of the POFs.…”

Section: Materials Propertiesmentioning

confidence: 99%

Adaptive polymer fiber neural device for drug delivery and enlarged illumination angle for neuromodulation

Sui¹,

Meneghetti²,

Kaur³

et al. 2022

J. Neural Eng.

View full text Add to dashboard Cite

Objective.Optical fiber devices constitute significant tools for the modulation and interrogation of neuronal circuitry in the mid and deep brain regions. The illuminated brain area during neuromodulation has a direct impact on the spatio-temporal properties of the brain activity and depends solely on the material and geometrical characteristics of the optical fibers. In the present work, we developed two different flexible polymer optical fibers (POFs) with integrated microfluidic channels (MFCs) and an ultra-high numerical aperture (UHNA) for enlarging the illumination angle to achieve efficient neuromodulation. Approach. Three distinct thermoplastic polymers: polysulfone (PSU), polycarbonate (PC), and fluorinated ethylene propylene (FEP) were used to fabricate two step-index UHNA POF neural devices using a scalable thermal drawing process. The POFs were characterized in terms of their illumination map as well as their fluid delivery capability in phantom and adult rat brain slices. Main results. A 100-fold reduced bending stiffness of the proposed fiber devices compared to their commercially available counterparts has been found. The integrated MFCs can controllably deliver dye (trypan blue) on-demand over a wide range of injection rates spanning from 10 nL/min to 1000 nL/min. Compared with commercial silica fibers, the proposed UHNA POFs exhibited an increased illumination area by 17% and 21% under 470 and 650 nm wavelength, respectively. In addition, a fluorescent light recording experiment has been conducted to demonstrate the ability of our UHNA POFs to be used as optical waveguides in fiber photometry. Significance. Our results overcome the current technological limitations of fiber implants that have limited illumination area and we suggest that soft neural fiber devices can be developed using different custom designs for illumination, collection, and photometry applications. We anticipate our work to pave the way towards the development of next-generation functional optical fibers for neuroscience.

show abstract

Optical properties of sputtered fluorinated ethylene propylene and its application to surface-plasmon resonance sensor fabrication

Cited by 6 publications

References 11 publications

Optimization of layer structure supporting long range surface plasmons for surface plasmon-enhanced fluorescence spectroscopy biosensors

Optimization of layer structure supporting long range surface plasmons for surface plasmon-enhanced fluorescence spectroscopy biosensors

Fluoropolymer Film Formation by Electron Activated Vacuum Deposition

Adaptive polymer fiber neural device for drug delivery and enlarged illumination angle for neuromodulation

Contact Info

Product

Resources

About