Plasma Synthesis of Hydrocarbon/Fluorocarbon Thin Films with Compositional Gradients

Abstract

Plasma enhanced chemical vapor deposition is used to synthesize hydrocarbon/fluorocarbon thin films with compositional gradients by continuously changing the ratio of gases in a C 3 F 8 / H 2 plasma. The films are characterized using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, water contact angle, and scanning electron microscopy. Using these methods, along with gas-phase diagnostics, film chemistry and the underlying deposition mechanisms are elucidated, leading to a model that accurately predicts film thickness. ) 282 284 286 288 290 292 294 296 Intensity (a.u.) Binding Energy (eV

Evaluation of polymer hydrophobic recovery behavior following H2O plasma processing

“…For example, the BE of the OCO group after one month is 0.8 eV lower when compared to the freshly treated PP sample. Shifts in BE such as these result from changes in the local chemical environment of a functional group and are discussed further below.…”

“…Although elemental composition data cannot be used to follow surface reorganization, high‐resolution XPS peak fitting does give us insight into this process. Work described previously correlates shifts in C 1s CF x BEs with changes in the local chemical environment. As the local concentration of fluorine decreased, the BEs of individual moieties decreased because of the lower electron withdrawing power on the carbon center.…”

Ar/O2 and H2O plasma surface modification of SnO2 nanomaterials to increase surface oxidation

“…[22][23][24] Substrates were placed in the center of the coil region and the reactor was pumped to base pressure (5-10 mTorr) for ~10 min. For Ar/O 2 plasma treatments, the gas flow rates were 10 and 15 sccm, respectively, resulting in a steady-state total system pressure of 145 mTorr after 5 min of gas flow (no plasma).…”

Growth of a Surface-Tethered, All-Carbon Backboned Fluoropolymer by Photoactivated Molecular Layer Deposition

“…The pMLD films also have thickness control under 5 nm, which is difficult to achieve via traditional CVD methods. 15,18,19,25 Additionally, the film shows exceptional thermal stability up to 400 °C as well as the ability to be photopatterned, a useful capability that has not been previously shown in MLD synthesis. These characteristics may enable area-selective deposition techniques with applications toward the fabrication of micro-and nanoelectronic devices.…”

“…Thin film polymers with carbon backbones possess important properties such as conductivity, photoresistance, and high stability, though they have not yet been developed via MLD. The MLD polymer in this work also contains a fluorinated functionality, similar to thin film fluoropolymers that are typically grown using chemical vapor deposition (CVD) methods, − a class of materials that have been studied extensively for its variety of applications toward membranes, microfluidics, hydrophobic biomaterials, and area-selective ALD . Unlike CVD fluoropolymers, however, which are made using harsh plasma or hot wire conditions that can cause a myriad of CF x groups within the film, the pMLD monomers introduced here do not undergo degradation upon deposition, resulting in well-defined polymer films.…”