Electrical, Transport, and Optical Properties of Multifunctional Graphitic Films Synthesized on Dielectric Surfaces by Nickel Nanolayer-Assisted Pyrolysis

Abstract

We demonstrate that predepositing on the dielectric surface a nanometrically thin nickel film is sufficient to transform amorphous pyrolyzed photoresist film (PPF) into a graphitic film (GRF) enriched with nickel particles. The GRF shows three orders of magnitude higher carrier mobility than that of amorphous PPF, while its electrical conductivity doubles after etching away the nickel remains. The pronounced 2D peak in the Raman spectrum, almost dispersionless absorbance in the spectral range of 750 -2000 nm, and saturable absorption coefficient indicate that GRF possesses graphene-like band structure. The proposed cost-efficient and scalable synthesis route opens avenues towards fabrication of micron size patterned graphitic structures of any shape directly on a dielectric substrate. Having graphene-like transport and electrical properties at the 20 times higher absorbance than the single layer graphene, GRF is attractive for fabrication of fast modulators of optical radiation, bolometers and other photonics and optoelectronic devices that require an enhanced optical absorption.

Coupling between structural properties and charge transport in nano-crystalline and amorphous graphitic carbon films, deposited by electron-beam evaporation

“…As it was shown [20], the main contribution to the D band originates from oscillations that meet the condition q ≈ 2 k, where k is the wave vector of the electron participating in the transition (a 'quasiselection' rule). It is important to note that the A 1g modes are inherent in clusters of six-atomic aromatic rings with sp 2 -bonds so that the D band can serve as an indicator of the presence of graphite-like clusters in the carbon structure [18,21]. As opposed to band D, G band is observed in any organization of carbon bonds, including all possible rings and chains, as well as the disordered carbon bonds.…”

Electrical impedance sensing of organic pollutants with ultrathin graphitic membranes

“…Pyrolyzed photoresist films (PPF) with and without Ni catalytic layer were fabricated following the routes developed in [24]. Briefly, first 300 μl of nLoF resist (AZR 1:4) were deposited on SiO 2 wafer through spin coating at 3000 rpm for 60 s, followed by 1 min bake at 110 °C.…”

“…The same procedure has been followed for the fabrication of graphitized PPF (PPF+Ni). However the nLof resists was deposited on a SiO 2 substrate, pre-covered with 10 nm thick catalytic Ni layer [24].…”

“…In this paper, we report the implementation of thin graphitic membranes, i.e. pyrolyzed photoresist (PPF) [24], pyrolytic carbon (PyC) [25], and multilayer graphene (MLG) in EIS based sensors. Depending on the synthesis method, graphitic films may differ by conductivity and crystallinity (from highly ordered multi-layered graphene to almost amorphous pyrolyzed resist and pyrolytic carbon) being composed of either large (up to several microns) or small (5-10 nm) graphene flakes.…”

Pyrolyzed photoresist thin film: Effect of electron beam patterning on DC and THz conductivity

“…The relatively low electrical conductivity of PPF [10] does not rule out practical applications of these carbon films. Indeed, the chemical stability and robustness of PPFs are beneficial for biomedical [11][12][13], electrochemical [14][15][16] and microelectromechanical applications [17][18][19][20].…”