Controlling the flux of reactive species: a case study on thin film deposition in an aniline/argon plasma

Abstract

The plasma based synthesis of thin films is frequently used to deposit ultra-thin and pinhole-free films on a wide class of different substrates. However, the synthesis of thin films by means of low temperature plasmas is rather complex due to the great number of different species (neutrals, radicals, ions) that are potentially involved in the deposition process. This contribution deals with polymerization processes in a capacitively coupled discharge operated in a mixture of argon and aniline where the latter is a monomer, which is used for the production of plasma-polymerized polyaniline, a material belonging to the class of conductive polymers. This work will present a particular experimental approach that allows to (partially) distinguish the contribution of different species to the film growth and thus to control to a certain extent the properties of the resulting material. The control of the species flux emerging from the plasma and contributing to the film growth also sheds new light on the deposition process, in particular with respect to the role of the ion component. The analysis of the produced films has been performed by means of Fourier Transform Infrared spectroscopy (FTIR) and Near Edge X-ray Absorption Fine Structure spectroscopy (NEXAFS).

Temporal afterglow between two pulses of repetitively pulsed argon-acetylene plasma: measuring electron and negatively charged species densities

“…On the practical side, applications range from the synthesis of polymers [6], nanostructures [7], and functionalized nanoparticles [8] to contamination control in photolithography [9,10] and plasma diagnostics [11].…”

Controlled deposition of plasma‐polyaniline thin film by PECVD: Understanding the influence of aniline to argon ratio

“…It was moreover demonstrated that argon/aniline plasmas contain negative ions, which are formed through complex surface reactions with the electrodes, requiring a wall conditioning for a stable deposition process. [64,65] It can be expected that many parameters (pressure, power, gas flow, pumping speed, pulse frequency, and duty cycle) as well as reactor engineering aspects (dimensions, materials, or electrodes geometry) will impact the discharge properties and thus the thin-film deposition. However, one of the most important parameters (for a given power) is the gas mixing ratio, i.e.…”