Plasma Active Species Research Articles

GAS PRODUCTS OF ARGON PLASMA INTERACTION WITH POLYARAMID AND POLY(ETHYLENE TEREPHTHALATE)

Non-equilibrium plasma is widely used for surface modification of polymer materials. Reactions of plasma active species with polymers lead not only to the surface modification, but to the formation of gaseous products, which change the plasma composition and internal plasma parameters. It results in the dependence of surface etching and modification kinetics on the quantity of material been treated (on sample sizes in a reactor). These phenomena are known as so called “loading effect” and have been studied for the treatment of polypropylene and polyimide films, poly(ethylene terephthalate) films and fabrics in oxygen and air plasma. It can be expected that gas products of noble gas plasma action on polymers will change strongly plasma parameters and modification results. In this paper, experimental data are represented on composition of gas products and their evolution rates at the treatment of polyaramid films, fibers and poly(ethylene terephthalate) fabric in low-pressure argon plasma. Poly(ethylene terephthalate) textile fabric (PET) made of monofilament yarns (SAATI, S.p.A., Italy) and polyaramide (PA) films and complex yarns “Rusar®” (Termotex, Russia) were used in experiments. Direct current discharge was excited in a flow of argon (technical grade) in a glass tube reactor with 3 cm inner diameter. Fabric samples were placed as cylinders on the reactor wall in the discharge positive column. Square of PET samples was varied from 18 to 111 cm2. The PA yarns with the total length of 550 or 1020 cm were placed in the reactor on special holder with the length of 20 cm. Total gas pressure in reactor was varied from 30 to 300 Pa at discharge current of 20 – 110 mA. Gas flow rate in the reactor was kept constant and equal to 30 cm´s-1. Gas phase analysis was carried out by the methods of plasma emission spectroscopy and mass-spectrometry. Plasma emission spectra and mass-spectra show evolution of H2, CO and H2O molecules at the treatment of PA and PET in argon plasma. Evolution rates for different gas products and their mole fractions have been obtained as functions of total gas pressure. Increase in polymer sample square has been shown to result in changing the ratios between evolution rates for different gas products. Sum of CO, H2 and H2O mole fractions increases with polymer sample square and decreases with gas pressure. Dissociation of molecular gas products results in the changing plasma active species. Oxygen and hydrogen atom lines and OH emission bands are observed in plasma emission spectra. Alteration of intensity ratio for О(3p3P ® 3s3S0) and Ar (4p3D3 ® 4s3P2) lines (IO/IAr) versus time after discharge starting shows the possible participation of oxygen atoms in heterogeneous reactions with polymers. Evolution of molecular gas products of heterogeneous reactions influences plasma properties and rates of plasma chemical reactions. The data obtained will be used for the further analysis of mechanisms of heterogeneous reactions of plasma active species with polymers.

Power density measurements to optimize AC plasma jet operation in blood coagulation.

In this paper, the plasma power density and corresponding plasma dose of a low-cost air non-thermal plasma jet (ANPJ) device are estimated at different axial distances from the nozzle. This estimation is achieved by measuring the voltage and current at the substrate using diagnostic techniques that can be easily made in laboratory; thin wire and dielectric probe, respectively. This device uses a compressed air as input gas instead of the relatively-expensive, large-sized and heavy weighed tanks of Ar or He gases. The calculated plasma dose is found to be very low and allows the presented device to be used in biomedical applications (especially blood coagulation). While plasma active species and charged-particles are found to be the most effective on blood coagulation formation, both air flow and UV, individually, do not have any effect. Moreover, optimal conditions for accelerating blood coagulation are studied. Results showed that, the power density at the substrate is shown to be decreased with increasing the distance from the nozzle. In addition, both distances from nozzle and air flow rate play an important role in accelerating blood coagulation process. Finally, this device is efficient, small-sized, safe enough, of low cost and, hence, has its chances to be wide spread as a first aid and in ambulance.

Inactivation of Shewanella putrefaciens by Plasma Activated Water

Plasma activated water (PAW) generated by atmospheric-pressure air microplasma arrays is a solution containing a variety of reactive species. Here we investigate the effects of different applied voltage and water-activated time on bactericidal activities against Shewanella putrefaciens (S. putrefaciens). Our measurements showed that the sterilization efficiency of S. putrefaciens by PAW could be up to 2.0 Log Reduction. Scanning electron microscopy image and DNA concentration measurement showed that the S. putrefaciens cells were damaged and deformed due to the PAW treatment. The physicochemical properties of PAW treated by different applied voltage and water-activated time were evaluated, including pH value, initial PAW temperature, and the concentrations of plasma-activated species, such as H2O2, NO 3 − , NO 2 − , and O3. Analysis indicates that the sterilization efficiency of S. putrefaciens treated by PAW was mainly determined by H2O2 concentration and pH value of PAW. This study provides a basis for the PAW potential applications in the disinfection of rotten food.

Kinetics and mechanisms for ion-assisted etching of InP thin films in HBr + Cl2 + Ar inductively coupled plasma with various HBr/Cl2 mixing ratios

The study of InP etching kinetics as well as the evaluation of InP etching mechanism in HBr + Cl2 + Ar inductively coupled plasma were carried out. Experiments on the measurements of the etching rates for InP, SiO2, and SiNx as well as plasma diagnostics using Langmuir probes and optical emission spectroscopy were conducted at a fixed total gas pressure (10 mTorr, or 1.33 Pa), input power (800 W), and bias power (200 W), and the variable parameter was the HBr/Cl2 mixing ratio. Zero-dimensional (global) plasma modeling provided data regarding the densities of the plasma active species as well as on the particle and energy fluxes to the etched surface. An increase in the Cl2 fraction in the feed gas yielded a non-monotonic InP etching rate with a maximum of ~120 nm/min at 35% Cl2. Model-based analysis of the InP etching kinetics revealed that 1) the InP etching process is mainly provided by the chemical etching pathway; 2) the non-monotonic change in the InP etching rate cannot be explained by the chemical effects of Br and Cl atoms; and 3) the HCl molecules may have sufficiently contributed to the chemical etching pathway.

PLASMA PARAMETERS AND ACTIVE SPECIES KINETICS IN CF4+C4F8+Ar GAS MIXTURE

This work discusses the relationships between the initial composition of the CF4 + C4F8 + Ar gas mixture, gas-phase characteristics and heterogeneous process kinetics under the condition of low-pressure inductively coupled plasma. The goals were to investigate how the CF4/C4F8 mixing ratio influences internal plasma parameters (electron temperature, electron density and ion bombardment energy) and kinetics of plasma active species as well as to analyze how the changes in above parameters may influence the dry etching characteristics, such as etching rates and selectivities. The investigation was carried out using the combination of plasma diagnostics by double Langmuir probes and 0-dimensional plasma modeling. Both experiments and calculations were carried out at constant gas pressure (10 mTorr), input power (800 W) and bias power (150 W) while the CF4/C4F8 mixing ratio was varied through the partial flow rates for corresponding gases. It was shown that the substitution of CF4 for C4F8 in the CF4+C4F8+Ar feed gas lowers F atom formation rates and causes the decreasing F atom flux to the treated surface due to decreasing their volume density. It was proposed that an increase in the densities and fluxes of unsaturated CFx (x=1,2) radicals toward C4F8-rich plasmas at the nearly constant ion energy flux (i.e. at the nearly constant efficiency of ion bombardment) causes a decrease in the effective reaction probability for F atoms through the increasing thickness of the fluorocarbon polymer film on the treated surface.Forcitation:Efremov A.M., Murin D.B., Kwon K.H. Plasma parameters and active species kinetics CF4+C4F8+Ar gas mixture. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N4-5. P. 31-36

A comparative study on the transdermal penetration effect of gaseous and aqueous plasma reactive species

To improve the depth of plasma active species in the skin, it is very important to develop skin disease treatment using plasma. In this article, an air plasma source was used to work directly with the skin of a mouse. A tortuous pathway, hair follicles, electroporation and a microneedle do not aid the transdermal delivery of gaseous plasma active species, therefore these gaseous plasma active species cannot penetrate mouse skin with a thickness of ~0.75 mm. The plasma activated water (PAW) produced by the air plasma source was used to study the transdermal penetration of the aqueous plasma activated species. This aqueous plasma activated species can penetrate the skin through hair follicles, intercellular and transcellular routes. The pH of the PAW did not affect the penetration efficiency of the aqueous plasma active species.

Plasma CVD of hydrogenated boron-carbon thin films from triethylboron.

Low-temperature chemical vapor deposition (CVD) of B-C thin films is of importance for neutron voltaics and semiconductor technology. The highly reactive trialkylboranes, with alkyl groups of 1-4 carbon atoms, are a class of precursors that have been less explored for low-temperature CVD of B-C films. Herein, we demonstrate plasma CVD of B-C thin films using triethylboron (TEB) as a single source precursor in an Ar plasma. We show that the film density and B/C ratio increases with increasing plasma power, reaching a density of 2.20 g/cm3 and B/C = 1.7. This is attributed to a more intense energetic bombardment during deposition and more complete dissociation of the TEB molecule in the plasma at higher plasma power. The hydrogen content in the films ranges between 14 and 20 at. %. Optical emission spectroscopy of the plasma shows that BH, CH, C2, and H are the optically active plasma species from TEB. We suggest a plasma chemical model based on β-hydrogen elimination of C2H4 to form BH3, in which BH3 and C2H4 are then dehydrogenated to form BH and C2H2. Furthermore, C2H2 decomposes in the plasma to produce C2 and CH, which together with BH and possibly BH3-x(C2H5)x are the film forming species.

On the relationships between plasma chemistry, etching kinetics and etching residues in CF4+C4F8+Ar and CF4+CH2F2+Ar plasmas with various CF4/C4F8 and CF4/CH2F2 mixing ratios

In this work, we investigated how the CF4/C4F8 and CF4/CH2F2 mixing ratios in CF4+C4F8+Ar and CF4+CH2F2+Ar inductively coupled plasmas influence plasma parameters, densities and fluxes of plasma active species and etching characteristics (process kinetics, etching rates and selectivities, etching residues) for both Si and SiO2. For this purpose, we employed surface diagnostics by x-ray photoelectron spectroscopy (XPS), plasma diagnostics by Langmuir probes and 0-dimensional plasma model. It was found that the substitution of CF4 for CH2F2 causes the stronger decreases in both F atom flux and ion energy flux compared with the effect of C4F8. Accordingly, the CF4+CH2F2+Ar mixture provides the deeper fall of both Si and SiO2 etching rates, leaves the higher amount of the fluorocarbon polymer on the etched surface (especially in the case of Si) and results in a bit higher SiO2/Si etching selectivity. It was shown also that, in both gas systems, the etching process appears in the steady-state regime. The mechanisms influencing the etching/polymerization balance were discussed based on the correlation between Si and SiO2 etching rates with fluxes of plasma active species.

Formation mechanism of bead-chain-like ZnO nanostructures from oriented attachment of Zn/ZnO nanocomposites prepared via DC arc discharge in liquid

Bead-chain-like ZnO nanoparticles (NPs) formed in colloidal solution from oriented attachment (OA) of spherical nanoparticles. Arc discharge in liquid is a cost-effective method for quick mass production of nanostructured materials without considerable environmental footprints. Applying voltage across two zinc rods as electrodes, which were immersed in water cause explosion of electrodes and plasma generation. Zn/ZnO nanocomposites produced by interaction of different active species in high-pressure and high-temperature plasma at the solid-liquid interface. Different sized nanoparticles with diameters of 26, 35, 40 and 60nm at applied discharge currents of 150, 100, 50 and 20A respectively, were fabricated in water without any chemical additives. The results showed bead-like oriented attachments appeared with increasing the applied current during synthesis. Length of aggregates increases from 114nm to 120nm with the applied current of the arc discharge. The mechanism of OA of ZnO NPs was investigated by calculating the attractive and repulsive forces based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed for characterization of particle size, shape, and investigation of bead-like aggregates. X-ray diffraction (XRD) analysis was used to study the crystal structure and phase composition of the bead-chain like nanostructures. Finally, zeta potential analysis was used to measure surface charges and study the mechanism of oriented attachment. The results provide a simple and flexible method for synthesis of Zn/ZnO bead-chain like nanostructures.

On the Control of Plasma Parameters and Active Species Kinetics in CF4 + O2 + Ar Gas Mixture by CF4/O2 and O2/Ar Mixing Ratios

The effects of both CF4/O2 and Ar/O2 mixing ratios in three-component CF4 + O2 + Ar mixture on plasma parameters, densities and fluxes of active species determining the dry etching kinetics were analyzed. The investigation combined plasma diagnostics by Langmuir probes and zero-dimensional plasma modeling. It was found that the substitution of CF4 for O2 at constant fraction of Ar in a feed gas produces the non-monotonic change in F atom density, as it was repeatedly reported for the binary CF4/O2 gas mixtures. At the same time, the substitution of Ar for O2 at constant fraction of CF4 results in the monotonic increase in F atom density toward more oxygenated plasmas. The natures of these phenomena as well as theirs possible impacts on the etching/polymerization kinetics were discussed in details.

Comparative research of plasma-assisted milling and traditional milling in synthesizing AlN

In this paper, traditional milling and discharge plasma-assisted milling are employed to synthesize aluminum nitride (AlN) powder at nanometer scale by milling the mixture of aluminum and lithium hydroxide monohydrate. AlN powders can be generated in traditional milling and plasma-assisted milling in an hour milling time. Differential thermal analysis curves show that the reaction temperature of the powders treated by plasma-assisted milling is lower than that of traditional milling. These results indicate that plasma-assisted milling has higher efficiency in the synthesis of AlN, getting smaller crystallite size and activating powder. Moreover, an optical emission spectrum is employed to demonstrate the active species in plasma. The different formation process of AlN in the two-milling process, and the promotion effects of plasma in the milling process are discussed.

Potential applications of nonthermal plasmas against biofilm-associated micro-organisms invitro.

Biofilms as complex microbial communities attached to surfaces pose several challenges in different sectors, ranging from food and healthcare to desalination and power generation. The biofilm mode of growth allows microorganisms to survive in hostile environments and biofilm cells exhibit distinct physiology and behaviour in comparison with their planktonic counterparts. They are ubiquitous, resilient and difficult to eradicate due to their resistant phenotype. Several chemical-based cleaning and disinfection regimens are conventionally used against biofilm-dwelling micro-organisms invitro. Although such approaches are generally considered to be effective, they may contribute to the dissemination of antimicrobial resistance and environmental pollution. Consequently, advanced green technologies for biofilm control are constantly emerging. Disinfection using nonthermal plasmas (NTPs) is one of the novel strategies having a great potential for control of biofilms of a broad spectrum of micro-organisms. This review discusses several aspects related to the inactivation of biofilm-associated bacteria and fungi by different types of NTPs under invitro conditions. A brief introduction summarizes prevailing methods in biofilm inactivation, followed by introduction to gas discharge plasmas, active plasma species and their inactivating mechanism. Subsequently, significance and aspects of NTP inactivation of biofilm-associated bacteria, especially those of medical importance, including opportunistic pathogens, oral pathogenic bacteria, foodborne pathogens and implant bacteria, are discussed. The remainder of the review discusses majorly about the synergistic effect of NTPs and their activity against biofilm-associated fungi, especially Candida species.

Improving Internal Cell Colonization of Porous Scaffolds with Chemical Gradients Produced by Plasma Assisted Approaches.

Cell colonization of the surrounding environment is a very significant process in both physiological and pathological events. In order to understand the tissue regeneration process and thereby provide guidance principles for designing new biomaterials, it is of paramount importance to study the cell colonization in the presence of physical, chemical, and biological cues. Flat "gradient" materials are generally used with this purpose. Three dimensional gradient scaffolds mimicking more precisely the situation in vivo are somewhat more complex to fabricate and characterize. Scaffolds for Tissue Engineering (TE) made of hydrophobic synthetic polymers do not allow good cell colonization: far from their periphery, in fact, internal cell colonization is usually low. In this research poly-ε caprolactone (PCL) scaffolds have been "decorated" with chemical gradients both on top and along their thickness by means of cold plasma processes, in order to improve cell colonization of their core. Plasma treatments with a mixture of argon and oxygen (Ar/O2), as well as plasma deposition of differently cross-linked poly(ethylene oxide) (PEO)-like coatings, have been performed. This study establishes that cross-linked PEO-like domains interspaced with native PCL ones deposited only on top of the scaffold (i.e., coating that penetrates less than 300 μm inside the scaffold) are more effective in promoting cell colonization across the scaffolds than the other tested materials including superhydrophilic samples and that ones produced by tested double step approaches. Last but not least, one result of this research is that, in the case of plasma coatings with low deposition rates and porous materials with a low pore interconnectivity, it is possible to improve penetration of low pressure plasma active species inside the scaffold's core thorough a pretreatment of the porous materials (i.e., penetration up to 4500 mm far from topside).

Influence of argon fraction on plasma parameters in H2-N2mixture discharge with cathodic cage

Low-pressure H 2 -N 2 mixture pulsed DC plasmas with a cathodic cage (active screen) are widely used for plasma nitriding applications. In this study, the low-pressure H 2 -N 2 mixture plasma with a cathodic cage generated by 50 Hz pulsed DC source is investigated with triple Langmuir probe and optical emission spectroscopy. The electron temperature ( T e LP ) and electron number density ( n e ) are measured using a triple Langmuir probe (TLP). The excitation temperature ( T exc OES ) is calculated spectroscopically using Boltzmann plot method whereas nitrogen dissociation fraction is estimated using actinometry as well as the intensity ratio method ( I N (746.83 nm)/ I N2 (337.1 nm)). The results show that the electron and excitation temperatures, electron density and nitrogen atomic species density [N] all increase with the argon admixture, however, the important molecular ionized species density [N 2 + ] significantly decreases beyond 30% addition. This study provides useful information about the influence of the argon addition on plasma parameters and active species generation. As a result it helps to optimize the plasma nitriding system as a function of argon admixture to avoid random trials in the processing.

On the Etching Mechanisms of SiC Thin Films in CF4/CH2F2/N2/Ar Inductively Coupled Plasma

Etching mechanisms of SiC thin films in CF4/CH2F2/N2/Ar inductively coupled plasmas were studied based on the correlations between measured SiC etching rates and model-predicted fluxes of plasma active species. Plasma chemistry was analyzed using Langmuir probe diagnostics, optical emission spectroscopy and 0-dimensional (global) plasma modeling. It was found that, under the given set of process conditions, the SiC etching kinetics is not affected by the thickness of the fluorocarbon polymer film and corresponds to the steady-state ion-assisted chemical reaction with the domination of the chemical etching pathway. It was proposed that the reaction probability between SiC and F atoms depends on both ion energy flux and the flux of polymerizing radicals through the balance active surface sites acceptable for the adsorption of F atoms.

Functional and rheological properties of cold plasma treated rice starch

The present work deals with aimed to study the effect of cold plasma treatment on the functional and rheological properties of rice starch using two different power levels (40 and 60W). The changes in amylose content, turbidity, pH, water and fat absorption due to plasma treatment were evaluated. Where decrease in the turbidity and pH after the treatment was observed. Gel hydration properties and syneresis study revealed that there is an increase in leaching of amylose molecules after the treatment. Rapid Visco Analyzer examination showed an increase in pasting and final viscosities. From G′ and G″ moduli determination we observed that there is decrease in retrogradation tendency of starch gels. XRD did not show any change in A-type pattern but decrease in the relative crystallinity was observed due to depolymerization caused by active plasma species. FTIR shows some of the additional functional groups after treatment. SEM showed formation of fissures on the surface of starch granules due to etching caused by the plasma species. Thus, plasma treatment can be one of the methods for physical modification of starch.

Cylindrical dielectric barrier discharge plasma catalytic effect on chemical methods of silver nano-particle production

In this study, cylindrical dielectric barrier discharge plasma was used to study the catalytic effect on chemical methods of silver nano-particles for the first time. In this method, the processing time is short and the temperature of reaction is low. Also, the reactor is very simple, inexpensive, and accessible. In this work, pure AgNO3 as the precursor agent and poly vinyl pyrrolidone as the macromolecular surfactant were dissolved in ethanol as the solvent. UV-Vis and XRD were used to identify the colloidal and powder nano-particles, respectively. Optical emission spectroscopy was also used to identify the active species in plasma. Effects of gas flow rate, voltage, volume of solution, and processing time were also studied. Moreover, TEM and SEM images presented the mean diameter of nano-particle size around 10 to 20 nm. The results have been very promising.

Nonthermal plasma treatment of Aspergillus spp. spores on hazelnuts in an atmospheric pressure fluidized bed plasma system: Impact of process parameters and surveillance of the residual viability of spores

In this study, the impact of fluidized bed reactor diameters and plasma forming gases on inactivation efficiency of the Atmospheric Pressure Fluidized Bed Plasma (APFBP) system for aflatoxigenic spores of Aspergillus flavus and Aspergillus parasiticus on hazelnuts were investigated. Hazelnuts were artificially contaminated with A. flavus and A. parasiticus and then treated with dry air or nitrogen plasma for up to 5 min in two different fluidizing bed reactors of APFBP system at various plasma parameters. The decontamination effect of APFBP on Aspergillus spp. spores increased with the applied reference voltage and the frequency. The killing effect of plasma on the spores decreased as the diameter of the fluidized bed reactor increased. The fungicidal effects on A. flavus (4.17 log) and A. parasiticus (4.09 log) were found for air plasma treatment after 5 min. Due to the formation of active plasma species in the presence of oxygen, the air plasma generated at APFBP system was more effective than nitrogen plasma on decontamination of Aspergillus spp. spores, as expected. The total inactivation of the natural background microbiota of hazelnuts was obtained within maximum 2 min APFBP treatment. The aflatoxigenic spores that remained on hazelnuts after plasma process were considered as damaged cells, because they could not continue growing during storage at 25 °C for 30 days. The damage caused by APFBP treatment on Aspergillus spp. spore cells was demonstrated by using scanning electron microscopy.

Comparison of the Active Species in the RF and Microwave Flowing Discharges of N2 and Ar–20 %N2

We report a detailed comparison between RF and microwave (HF) plasmas of N2 and Ar–20 %N2 as well as in the corresponding afterglows by comparing densities of active species at nearly the same discharge conditions of tube diameter (5–6 mm), gas pressure (6–8 Torr), flow rate (0.6–1.0 slm) and applied power (50–150 W). The analysis reveals an interesting difference between the two cases; the length of the RF plasma (~25 cm) is measured to be much longer than that of HF (6 cm). This ensures a much longer residence time (10−2 s) of the active species in the N2 RF plasma [compared to that (10−3 s) of HF], providing a condition for an efficient vibrational excitation of N2(X, v) by (V–V) climbing-up processes, making the RF plasma more vibrationally excited than the HF one. As a result of high V–V plasma excitation in RF, the densities of the vibrationally excited N2(X, v > 13) molecules are higher in the RF afterglow than in the HF afterglow. Destruction of N2(X, v) due to the tube wall is estimated to be very similar between the two system as can be inferred from the γv destruction probability of N2(X, v > 3–13) on the tube wall (2–3 × 10−3 for both cases) obtained from a comparison between the density of N2(X, v > 3–9) in the plasmas to that of the N2(X, v > 13) in the long afterglows. Interestingly enough, densities of N-atoms and N2(A) metastable molecules in the afterglow regions, however, are measured to be very similar with each other. The measured lower density of N2 + ions than expected in the HF afterglow is rationalized from a high oxygen impurity in our HF setup since N2 + ions are very sensitive to oxygen impurity .

Influence of power density on high purity 63 mm diameter polycrystalline diamond deposition inside a 2.45 GHz MPCVD reactor

63 mm diameter polycrystalline diamond (PCD) films were synthesized via a microwave plasma chemical vapor deposition (MPCVD) reactor in 99% H2–1% CH4 atmosphere. Two different conditions, i.e. the typical condition (input power of 5 kW and gas pressure of 13 kPa) and the high power density condition (input power of 10 kW and gas pressure of 18 kPa), were employed for diamond depositions. The color changes of the plasma under the two proposed conditions with and without methane were observed by photographs. Likewise, the concentrations of hydrogen atoms and carbon active chemical species in plasma were analyzed by optical emission spectroscopy (OES). The morphologies and purity of the PCD films were investigated by scanning electron microscopy (SEM) and Raman spectroscopy, respectively. Finally, the transmission spectrum of the polished PCD plates was characterized by a UV–Vis–NIR spectrometer. Experimental results showed that both the concentrations of hydrogen atoms and carbon radicals increased obviously, with the boost input power and higher pressure. The films synthesized under the high power density condition displayed higher purity and more uniform thickness. The growth rates in 10 kW and 18 kPa reached ~7.7 µm h−1, approximately 6.5 times as much as that occurred in the typical process. Moreover, the polished plates synthesized under the high power density condition possessed a relatively high optical transmittance (~69%), approaching the theoretical values of approximately 71.4% in IR. These results indicate that the purity and growth rate of big-area PCD films could be simultaneously increased with power density.