Optical and structural study for DLC thin films prepared by plasma jet

S J Kadhem

doi:10.30723/ijp.v17i40.405

Abstract

Diamond-like carbon (DLC) homogeneous thin films were deposited from cyclohexane (Ccyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (C 6H12 ) liquid by using a plasma jet system which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 kv and kv and kv and kv and frequency 28 frequency 28frequency 28 frequency 28frequency 28frequency 28frequency 28frequency 28 kHz. kHz. The optical and structural properties and chemical bonding of these films were investigated. In this work, the effect of changing the distance between the substrate and the plasma torch (2, 2.5 and 3 cm) was studied. The flow rate of argon gas which used to generate the plasma was fixed (0.5 L/min). These films were characterized by UV–Visible spectrophotometer, X-ray diffractometer (XRD) and scanning electron microscopy (SEM) and Fourier transformation infrared spectroscopy (FTIR). The maximum absorption (λmax) appears around 312, 298.3 and 293.2 nm at the three distance between plasma torch and the substrate 2.5, 2 and 3 cm, respectively. The values of the optical energy gap are 3.47, 3.65 and 3.76 eV at a different distance (2, 2.5 and 3cm), respectively. In XRD diffraction pattern, The occurrence of diamond peaks and graphite peaks in the x-ray spectrum for these films Indicates that there is an occurrence of local ordered sp3 and sp2 for carbon domains and graphite respectively.

Highlights

Carbon shows itself in few different phases like diamond [1, 2] graphite, fullerenes [3, 4], nanotubes [5,6,7,8] and diamond-like carbon [9] because of its ability to hybridize in several structures, for example, tetrahedral, trigonal and linear coordinations [10]
This system is characterized by high efficiency; the small size of plasma jet enables us to deal with large areas, to give an advantage in dental treatment in medical use, which requires high correctness [12]
Numerous Layers of carbon nanoparticles deposited with 0.5L/min as a fixed flow rate of argon gas on quartz substrates with a thickness 200, 220, 250 nm at the different distance between the substrate and plasma torch (2, 2.5 and 3 cm), respectively

Summary

Introduction

Carbon shows itself in few different phases like diamond [1, 2] graphite, fullerenes [3, 4], nanotubes [5,6,7,8] and diamond-like carbon [9] because of its ability to hybridize in several structures, for example, tetrahedral (sp3), trigonal (sp2) and linear coordinations (sp1) [10]. Gas flows through the electrode at many controlled at a various flow rate and could be measured by unit (l/min) This system is characterized by high efficiency; the small size of plasma jet enables us to deal with large areas, to give an advantage in dental treatment in medical use, which requires high correctness [12]. It can be used for deposition nitrides, oxides and other materials of thin films [13]. There are three types of films depending on the sp fraction and hydrogen content These types are polymeric amorphous carbon (PAC), diamond-like carbon (DLC), and graphitic amorphous carbon (GAC) [15]

Experimental part

Measurements of optical properties

The scanning electron microscope analysis

Conclusions