The Electrical Properties of Plasma-Deposited Thin Films Derived from Pelargonium graveolens

• Main Authors: Ahmed Al-Jumaili, Surjith Alancherry, Kateryna Bazaka, Mohan V. Jacob
• Format: Article
• Language: English
• Published: MDPI AG 2017-10-01
• Series: Electronics
• Subjects: electrical properties; plasma-deposited films; Pelargonium graveolens; geranium; metal–insulator–metal
• Online Access: https://www.mdpi.com/2079-9292/6/4/86

Inherently volatile at atmospheric pressure and room temperature, plant-derived precursors present an interesting human-health-friendly precursor for the chemical vapour deposition of thin films. The electrical properties of films derived from Pelargonium graveolens (geranium) were investigated in metal–insulator–metal (MIM) structures. Thin polymer-like films were deposited using plasma-enhanced synthesis under various plasma input power. The J–V characteristics of thus-fabricated MIM were then studied in order to determine the direct current (DC) conduction mechanism of the plasma polymer layers. It was found that the capacitance of the plasma-deposited films decreases at low frequencies (C ≈ 10−11) and remains at a relatively constant value (C ≈ 10−10) at high frequencies. These films also have a low dielectric constant across a wide range of frequencies that decreases as the input RF power increases. The conductivity was determined to be around 10−16–10−17 Ω−1 m−1, which is typical for insulating materials. The Richardson–Schottky mechanism might dominate charge transport in the higher field region for geranium thin films.