RETRACTED: Study of Parylene-C Thin Film Deposited on Flat Substrates

Tsai, Fa Ta; Chuang, Chin Tun; Li, Tsai Cheng; Yu, Pei Chi

doi:10.4028/www.scientific.net/amm.217-219.1077

Cited by 3 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On probing Parylene-C coated CVD graphene samples by AFM before PMMA coating and after PMMA removal, we found an imperceptible change in the Parylene-C surface morphology. In addition, the PMMA residues on SiO 2 substrates (which have a similar adhesion to PMMA as Parylene-C) 67,68 show negligible traces of PMMA after the same removal procedure as above.…”

Section: Fabrication Of Micro-blister Devicesmentioning

confidence: 97%

Ultra-thin graphene–polymer heterostructure membranes

2016

View full text Add to dashboard Cite

The fabrication of arrays of ultra-thin conductive membranes remains a major challenge in realising large-scale micro/nano-electromechanical systems (MEMS/NEMS), since processing-stress and stiction issues limit the precision and yield in assembling suspended structures. We present the fabrication and mechanical characterisation of a suspended graphene-polymer heterostructure membrane that aims to tackle the prevailing challenge of constructing high yield membranes with minimal compromise to the mechanical properties of graphene. The fabrication method enables suspended membrane structures that can be multiplexed over wafer-scales with 100% yield. We apply a micro-blister inflation technique to measure the in-plane elastic modulus of pure graphene and of heterostructure membranes with a thickness of 18 nm to 235 nm, which ranges from the 2-dimensional (2d) modulus of bare graphene at 173 ± 55 N m to the bulk elastic modulus of the polymer (Parylene-C) as 3.6 ± 0.5 GPa as a function of film thickness. Different ratios of graphene to polymer thickness yield different deflection mechanisms and adhesion and delamination effects which are consistent with the transition from a membrane to a plate model. This system reveals the ability to precisely tune the mechanical properties of ultra-thin conductive membranes according to their applications.

show abstract

Section: Fabrication Of Micro-blister Devicesmentioning

confidence: 97%

Ultra-thin graphene–polymer heterostructure membranes

2016

View full text Add to dashboard Cite

show abstract

“…Plasma treatment is a widely used method to create stochastic nanostructures and to modify the surface roughness of Parylene-C [24,25,26] and other biomaterials [27,28]. …”

Section: Resultsmentioning

confidence: 99%

Surface Nanostructuring of Parylene-C Coatings for Blood Contacting Implants

et al. 2018

View full text Add to dashboard Cite

This paper investigates the effects on the blood compatibility of surface nanostructuring of Parylene-C coating. The proposed technique, based on the consecutive use of O2 and SF6 plasma, alters the surface roughness and enhances the intrinsic hydrophobicity of Parylene-C. The degree of hydrophobicity of the prepared surface can be precisely controlled by opportunely adjusting the plasma exposure times. Static contact angle measurements, performed on treated Parylene-C, showed a maximum contact angle of 158°. The nanostructured Parylene-C retained its hydrophobicity up to 45 days, when stored in a dry environment. Storing the samples in a body-mimicking solution caused the contact angle to progressively decrease. However, at the end of the measurement, the plasma treated surfaces still exhibited a higher hydrophobicity than the untreated counterparts. The proposed treatment improved the performance of the polymer as a water diffusion barrier in a body simulating environment. Modifying the nanotopography of the polymer influences the adsorption of different blood plasma proteins. The adsorption of albumin—a platelet adhesion inhibitor—and of fibrinogen—a platelet adhesion promoter—was studied by fluorescence microscopy. The adsorption capacity increased monotonically with increasing hydrophobicity for both studied proteins. The effect on albumin adsorption was considerably higher than on fibrinogen. Study of the proteins simultaneous adsorption showed that the albumin to fibrinogen adsorbed ratio increases with substrate hydrophobicity, suggesting lower thrombogenicity of the nanostructured surfaces. Animal experiments proved that the treated surfaces did not trigger any blood clot or thrombus formation when directly exposed to the arterial blood flow. The findings above, together with the exceptional mechanical and insulation properties of Parylene-C, support its use for packaging implants chronically exposed to the blood flow.

show abstract