Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon ... more Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon (100) substrates by a capacitively coupled 13.56 MHz RF plasma enhanced chemical vapour deposition (RF-PECVD) system, using acetylene (C 2 H 2) as process gas. DLC films were deposited at a constant power of 200 W with 100 sccm flow of C 2 H 2 and at deposition temperatures of 25ºC (RT), 150ºC and 300ºC. DLC films were characterized by Fourier-transform Infrared Spectroscopy (FTIR), Ellipsometry and Raman Spectroscopy. Characterization of DLC films for anti-reflective (AR) property by FTIR on double side coated silicon at room temperature showed enhancement in maximum transmission of about 89% in 3-5 μm wavelength. Raman and Ellipsometry analysis confirmed the formation of DLC films with Ad/Ag ratio of 0.53-0.82 and refractive index (n) of 2.3.
Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by ... more Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by partially replacing the amido groups from the complexes [Ti(NMe2)4] and [Ti(NEt2)4] via Brønstedt acid/base reactions, using the malonate-ligands di-isopropylmalonate (Hdpml) and di-tert-butylmalonate (Hdbml). Four representative complexes were synthesized and fully characterised by 1H NMR, 13C NMR, CHN analysis and mass spectrometry. The crystal structures of the six-coordinated complexes [Ti(NMe2)2(dbml)2] (3) and [Ti(NEt2)2(dbml)2] (4) are presented and discussed. The complexes are solids and the chemical and thermal characteristics of the complexes strongly depend on the substitution at the malonate ligand. While dpml containing complexes show a promising behaviour for classical MOCVD, dbml containing complexes seem to be more suitable for liquid injection-metal-organic chemical vapour deposition (LI-MOCVD). Based on its thermal characteristics, the most promising complex for thermal CVD, [Ti(NEt2)2(dpml)2] (2) was selected for preliminary MOCVD experiments, which indicate a good suitability for the deposition of TiO2 thin films.
Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of th... more Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of thin films of oxide materials as it offers advantages, such as deposition over large surface area, conformal coverage, selective area deposition, and a high degree of compositional ...
Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency ... more Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency based Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) at room temperature. Experiments were carried out using a flow rate of 100 sccm and 300 sccm of acetylene (C 2 H 2) gas and the bias voltage was varied from 300-450 V for DLC deposition. Scanning electron microscope (SEM) and transmission electron microscope (TEM) has been used to study the structure and morphology of the DLC coating. TEM results of DLC coatings deposited at 100 sccm C 2 H 2 flow suggest that some crystalline features of diamond are present in the disordered matrix of DLC. Mechanical properties of DLC coatings were studied using a nanoindenter. The results indicate that the hardest DLC film is obtained at 100 sccm flow rate of C 2 H 2 deposited at 450 V bias voltage of about 32.25 GPa. The results also indicate that the lowest coefficient of friction (COF) of about 0.04 in DLC film is obtained at 300 sccm flow rate of C 2 H 2 deposited at 400 V bias voltage. COF is found to be lower in high C 2 H 2 flow rate, wherever relatively softer DLC was deposited.
ABSTRACT MnO/C composite coatings were grown by the metalorganic chemical vapor deposition proces... more ABSTRACT MnO/C composite coatings were grown by the metalorganic chemical vapor deposition process on ceramic alumina in argon ambient. Characterization by various techniques confirms that these coatings are homogeneous composites comprising nanometer-sized MnO particles embedded in a matrix of nanometer-sized graphite. Components of the MnO/C composite coating crystalline disordered, but are electrically quite conductive. Resistance vs. temperature measurements show that coating resistance increases exponentially from a few hundred ohms at room temperature to a few megaohms at 30 K. Logarithmic plots of reduced activation energy vs. temperature show that the coating material undergoes a metal–insulator transition. The reduced activation energy exponent for the film under zero magnetic field was 2.1, which is unusually high, implying that conduction is suppressed at much faster rate than the Mott or the Efros–Shklovskii hopping mechanism. Magnetoconductance vs. magnetic field plots obtained at various temperatures show a high magnetoconductance (∼28.8%) at 100 K, which is unusually large for a disordered system, wherein magnetoresistance is attributed typically to weak localization. A plausible explanation for the unusual behavior observed in the carbonaceous disordered composite material is proposed.
Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency ... more Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency based Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) at room temperature. Experiments were carried out using a flow rate of 100 sccm and 300 sccm of acetylene (C 2 H 2) gas and the bias voltage was varied from 300-450 V for DLC deposition. Scanning electron microscope (SEM) and transmission electron microscope (TEM) has been used to study the structure and morphology of the DLC coating. TEM results of DLC coatings deposited at 100 sccm C 2 H 2 flow suggest that some crystalline features of diamond are present in the disordered matrix of DLC. Mechanical properties of DLC coatings were studied using a nanoindenter. The results indicate that the hardest DLC film is obtained at 100 sccm flow rate of C 2 H 2 deposited at 450 V bias voltage of about 32.25 GPa. The results also indicate that the lowest coefficient of friction (COF) of about 0.04 in DLC film is obtained at 300 sccm flow rate of C 2 H 2 deposited at 400 V bias voltage. COF is found to be lower in high C 2 H 2 flow rate, wherever relatively softer DLC was deposited.
Abstract Diamond-like Carbon (DLC) for IR antireflective properties is currently being used in th... more Abstract Diamond-like Carbon (DLC) for IR antireflective properties is currently being used in the coating of germanium based IR optics. These DLC coatings offer better wear resistance as compared to traditional anti-reflective (AR) coatings. The current work emphasizes the development of IR optics using germanium substrate coated with DLC which typically covers IR transmission in wavelength regions like 3–7 μm and 9–15 μm. In order to study IR transmission, an optimum film thickness of DLC was calculated and coated on a double sided polished germanium substrate. DLC was coated on a single side of a germanium substrate, as well as on both sides of germanium. DLC has been deposited using Radio Frequency Plasma Enhanced Chemical Vapour Deposition (RF-PECVD) at room temperature without the use of any intermediary buffer layers required for adhesion and high hardness values were achieved at room temperature as compared to existing literature. The transmission of IR through DLC coated germanium windows was measured using Fourier Transform Infra-Red (FTIR) spectroscopy. A comparison between transmission through a single side and double sided DLC coating on germanium has been demonstrated. The hardness of the film was measured using nanoindentation. Scratch test was also performed using nanoindentation. Adhesion and salt spray tests were performed as per MIL standards. With double sided DLC coating, a peak transmission value of 93% is achieved in 3–7 μm and the average hardness of DLC is measured to be 32.74 GPa.
Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of th... more Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of thin films of oxide materials as it offers advantages, such as deposition over large surface area, conformal coverage, selective area deposition, and a high degree of compositional ...
Radio frequency (RF) plasma enhanced chemical vapour deposition (PECVD) technique was used to mak... more Radio frequency (RF) plasma enhanced chemical vapour deposition (PECVD) technique was used to make a diamond like carbon (DLC) coating on silicon (100) substrate. The deposition was carried out using C 2 H 2 as the process gas, at different temperatures, 25°C (room temperature) and 300°C with constant power and flow rate. Characterization techniques such as ellipsometry and Raman spectroscopy were used to characterize these samples. Raman analysis of DLC coatings at different temperature is carried out in detail for two different excitation wavelengths i.e. 514 and 785 nm and, results are presented in the paper. Blue-shiftis observed in both D and G peaks of Raman spectrum with increase in deposition temperature, which indicates the formation of compressive strain in high temperature deposited DLC coatings. Dispersion in both D and G peaks is observed for different excitation wavelength suggesting that the coating is hydrogenated DLC. The degree of hydrogenation of the DLC coating appears to decrease with respect to the deposition temperature. Nano-indentation study shows a marginal increase in hardness with increase in deposition temperature.
Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon ... more Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon (100) substrates by a capacitively coupled 13.56 MHz RF plasma enhanced chemical vapour deposition (RF-PECVD) system, using acetylene (C 2 H 2) as process gas. DLC films were deposited at a constant power of 200 W with 100 sccm flow of C 2 H 2 and at deposition temperatures of 25ºC (RT), 150ºC and 300ºC. DLC films were characterized by Fourier-transform Infrared Spectroscopy (FTIR), Ellipsometry and Raman Spectroscopy. Characterization of DLC films for anti-reflective (AR) property by FTIR on double side coated silicon at room temperature showed enhancement in maximum transmission of about 89% in 3-5 μm wavelength. Raman and Ellipsometry analysis confirmed the formation of DLC films with Ad/Ag ratio of 0.53-0.82 and refractive index (n) of 2.3.
Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by ... more Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by partially replacing the amido groups from the complexes [Ti(NMe2)4] and [Ti(NEt2)4] via Brønstedt acid/base reactions, using the malonate-ligands di-isopropylmalonate (Hdpml) and di-tert-butylmalonate (Hdbml). Four representative complexes were synthesized and fully characterised by 1H NMR, 13C NMR, CHN analysis and mass spectrometry. The crystal structures of the six-coordinated complexes [Ti(NMe2)2(dbml)2] (3) and [Ti(NEt2)2(dbml)2] (4) are presented and discussed. The complexes are solids and the chemical and thermal characteristics of the complexes strongly depend on the substitution at the malonate ligand. While dpml containing complexes show a promising behaviour for classical MOCVD, dbml containing complexes seem to be more suitable for liquid injection-metal-organic chemical vapour deposition (LI-MOCVD). Based on its thermal characteristics, the most promising complex for thermal CVD, [Ti(NEt2)2(dpml)2] (2) was selected for preliminary MOCVD experiments, which indicate a good suitability for the deposition of TiO2 thin films.
... Govt. of India). One of us (A. Varade) thanks Dr. Latha Kumari and Vaibhav Varade (Physics De... more ... Govt. of India). One of us (A. Varade) thanks Dr. Latha Kumari and Vaibhav Varade (Physics Dept., IISc, India) for vital discussions regarding charge transport. One of us (A. Varade) would like to thank Prof. S. Sampath (Dept. ...
Equilibrium thermodynamic analysis has been applied to the low-pressure MOCVD process using manga... more Equilibrium thermodynamic analysis has been applied to the low-pressure MOCVD process using manganese acetylacetonate as the precursor. “CVD phase stability diagrams” have been constructed separately for the processes carried out in argon and oxygen ambient, depicting the compositions of the resulting films as functions of CVD parameters. For the process conduced in argon ambient, the analysis predicts the simultaneous deposition of MnO and elemental carbon in 1:3 molar proportion, over a range of temperatures. The analysis predicts also that, if CVD is carried out in oxygen ambient, even a very low flow of oxygen leads to the complete absence of carbon in the film deposited oxygen, with greater oxygen flow resulting in the simultaneous deposition of two different manganese oxides under certain conditions. The results of thermodynamic modeling have been verified quantitatively for low-pressure CVD conducted in argon ambient. Indeed, the large excess of carbon in the deposit is found to constitute a MnO/C nanocomposite, the associated cauliflower-like morphology making it a promising candidate for electrode material in supercapacitors. CVD carried out in oxygen flow, under specific conditions, leads to the deposition of more than one manganese oxide, as expected from thermodynamic analysis (and forming an oxide–oxide nanocomposite). These results together demonstrate that thermodynamic analysis of the MOCVD process can be employed to synthesize thin films in a predictive manner, thus avoiding the inefficient trial-and-error method usually associated with MOCVD process development. The prospect of developing thin films of novel compositions and characteristics in a predictive manner, through the appropriate choice of CVD precursors and process conditions, emerges from the present work.
Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon ... more Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon (100) substrates by a capacitively coupled 13.56 MHz RF plasma enhanced chemical vapour deposition (RF-PECVD) system, using acetylene (C 2 H 2) as process gas. DLC films were deposited at a constant power of 200 W with 100 sccm flow of C 2 H 2 and at deposition temperatures of 25ºC (RT), 150ºC and 300ºC. DLC films were characterized by Fourier-transform Infrared Spectroscopy (FTIR), Ellipsometry and Raman Spectroscopy. Characterization of DLC films for anti-reflective (AR) property by FTIR on double side coated silicon at room temperature showed enhancement in maximum transmission of about 89% in 3-5 μm wavelength. Raman and Ellipsometry analysis confirmed the formation of DLC films with Ad/Ag ratio of 0.53-0.82 and refractive index (n) of 2.3.
Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by ... more Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by partially replacing the amido groups from the complexes [Ti(NMe2)4] and [Ti(NEt2)4] via Brønstedt acid/base reactions, using the malonate-ligands di-isopropylmalonate (Hdpml) and di-tert-butylmalonate (Hdbml). Four representative complexes were synthesized and fully characterised by 1H NMR, 13C NMR, CHN analysis and mass spectrometry. The crystal structures of the six-coordinated complexes [Ti(NMe2)2(dbml)2] (3) and [Ti(NEt2)2(dbml)2] (4) are presented and discussed. The complexes are solids and the chemical and thermal characteristics of the complexes strongly depend on the substitution at the malonate ligand. While dpml containing complexes show a promising behaviour for classical MOCVD, dbml containing complexes seem to be more suitable for liquid injection-metal-organic chemical vapour deposition (LI-MOCVD). Based on its thermal characteristics, the most promising complex for thermal CVD, [Ti(NEt2)2(dpml)2] (2) was selected for preliminary MOCVD experiments, which indicate a good suitability for the deposition of TiO2 thin films.
Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of th... more Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of thin films of oxide materials as it offers advantages, such as deposition over large surface area, conformal coverage, selective area deposition, and a high degree of compositional ...
Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency ... more Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency based Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) at room temperature. Experiments were carried out using a flow rate of 100 sccm and 300 sccm of acetylene (C 2 H 2) gas and the bias voltage was varied from 300-450 V for DLC deposition. Scanning electron microscope (SEM) and transmission electron microscope (TEM) has been used to study the structure and morphology of the DLC coating. TEM results of DLC coatings deposited at 100 sccm C 2 H 2 flow suggest that some crystalline features of diamond are present in the disordered matrix of DLC. Mechanical properties of DLC coatings were studied using a nanoindenter. The results indicate that the hardest DLC film is obtained at 100 sccm flow rate of C 2 H 2 deposited at 450 V bias voltage of about 32.25 GPa. The results also indicate that the lowest coefficient of friction (COF) of about 0.04 in DLC film is obtained at 300 sccm flow rate of C 2 H 2 deposited at 400 V bias voltage. COF is found to be lower in high C 2 H 2 flow rate, wherever relatively softer DLC was deposited.
ABSTRACT MnO/C composite coatings were grown by the metalorganic chemical vapor deposition proces... more ABSTRACT MnO/C composite coatings were grown by the metalorganic chemical vapor deposition process on ceramic alumina in argon ambient. Characterization by various techniques confirms that these coatings are homogeneous composites comprising nanometer-sized MnO particles embedded in a matrix of nanometer-sized graphite. Components of the MnO/C composite coating crystalline disordered, but are electrically quite conductive. Resistance vs. temperature measurements show that coating resistance increases exponentially from a few hundred ohms at room temperature to a few megaohms at 30 K. Logarithmic plots of reduced activation energy vs. temperature show that the coating material undergoes a metal–insulator transition. The reduced activation energy exponent for the film under zero magnetic field was 2.1, which is unusually high, implying that conduction is suppressed at much faster rate than the Mott or the Efros–Shklovskii hopping mechanism. Magnetoconductance vs. magnetic field plots obtained at various temperatures show a high magnetoconductance (∼28.8%) at 100 K, which is unusually large for a disordered system, wherein magnetoresistance is attributed typically to weak localization. A plausible explanation for the unusual behavior observed in the carbonaceous disordered composite material is proposed.
Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency ... more Diamond-like carbon (DLC) coatings have been deposited on Silicon wafers using a Radio Frequency based Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) at room temperature. Experiments were carried out using a flow rate of 100 sccm and 300 sccm of acetylene (C 2 H 2) gas and the bias voltage was varied from 300-450 V for DLC deposition. Scanning electron microscope (SEM) and transmission electron microscope (TEM) has been used to study the structure and morphology of the DLC coating. TEM results of DLC coatings deposited at 100 sccm C 2 H 2 flow suggest that some crystalline features of diamond are present in the disordered matrix of DLC. Mechanical properties of DLC coatings were studied using a nanoindenter. The results indicate that the hardest DLC film is obtained at 100 sccm flow rate of C 2 H 2 deposited at 450 V bias voltage of about 32.25 GPa. The results also indicate that the lowest coefficient of friction (COF) of about 0.04 in DLC film is obtained at 300 sccm flow rate of C 2 H 2 deposited at 400 V bias voltage. COF is found to be lower in high C 2 H 2 flow rate, wherever relatively softer DLC was deposited.
Abstract Diamond-like Carbon (DLC) for IR antireflective properties is currently being used in th... more Abstract Diamond-like Carbon (DLC) for IR antireflective properties is currently being used in the coating of germanium based IR optics. These DLC coatings offer better wear resistance as compared to traditional anti-reflective (AR) coatings. The current work emphasizes the development of IR optics using germanium substrate coated with DLC which typically covers IR transmission in wavelength regions like 3–7 μm and 9–15 μm. In order to study IR transmission, an optimum film thickness of DLC was calculated and coated on a double sided polished germanium substrate. DLC was coated on a single side of a germanium substrate, as well as on both sides of germanium. DLC has been deposited using Radio Frequency Plasma Enhanced Chemical Vapour Deposition (RF-PECVD) at room temperature without the use of any intermediary buffer layers required for adhesion and high hardness values were achieved at room temperature as compared to existing literature. The transmission of IR through DLC coated germanium windows was measured using Fourier Transform Infra-Red (FTIR) spectroscopy. A comparison between transmission through a single side and double sided DLC coating on germanium has been demonstrated. The hardness of the film was measured using nanoindentation. Scratch test was also performed using nanoindentation. Adhesion and salt spray tests were performed as per MIL standards. With double sided DLC coating, a peak transmission value of 93% is achieved in 3–7 μm and the average hardness of DLC is measured to be 32.74 GPa.
Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of th... more Metalorganic Chemical Vapour Deposition (MOCVD) is a versatile technique for the deposition of thin films of oxide materials as it offers advantages, such as deposition over large surface area, conformal coverage, selective area deposition, and a high degree of compositional ...
Radio frequency (RF) plasma enhanced chemical vapour deposition (PECVD) technique was used to mak... more Radio frequency (RF) plasma enhanced chemical vapour deposition (PECVD) technique was used to make a diamond like carbon (DLC) coating on silicon (100) substrate. The deposition was carried out using C 2 H 2 as the process gas, at different temperatures, 25°C (room temperature) and 300°C with constant power and flow rate. Characterization techniques such as ellipsometry and Raman spectroscopy were used to characterize these samples. Raman analysis of DLC coatings at different temperature is carried out in detail for two different excitation wavelengths i.e. 514 and 785 nm and, results are presented in the paper. Blue-shiftis observed in both D and G peaks of Raman spectrum with increase in deposition temperature, which indicates the formation of compressive strain in high temperature deposited DLC coatings. Dispersion in both D and G peaks is observed for different excitation wavelength suggesting that the coating is hydrogenated DLC. The degree of hydrogenation of the DLC coating appears to decrease with respect to the deposition temperature. Nano-indentation study shows a marginal increase in hardness with increase in deposition temperature.
Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon ... more Diamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon (100) substrates by a capacitively coupled 13.56 MHz RF plasma enhanced chemical vapour deposition (RF-PECVD) system, using acetylene (C 2 H 2) as process gas. DLC films were deposited at a constant power of 200 W with 100 sccm flow of C 2 H 2 and at deposition temperatures of 25ºC (RT), 150ºC and 300ºC. DLC films were characterized by Fourier-transform Infrared Spectroscopy (FTIR), Ellipsometry and Raman Spectroscopy. Characterization of DLC films for anti-reflective (AR) property by FTIR on double side coated silicon at room temperature showed enhancement in maximum transmission of about 89% in 3-5 μm wavelength. Raman and Ellipsometry analysis confirmed the formation of DLC films with Ad/Ag ratio of 0.53-0.82 and refractive index (n) of 2.3.
Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by ... more Novel mixed amido-malonato complexes of titanium are reported. The complexes were synthesized by partially replacing the amido groups from the complexes [Ti(NMe2)4] and [Ti(NEt2)4] via Brønstedt acid/base reactions, using the malonate-ligands di-isopropylmalonate (Hdpml) and di-tert-butylmalonate (Hdbml). Four representative complexes were synthesized and fully characterised by 1H NMR, 13C NMR, CHN analysis and mass spectrometry. The crystal structures of the six-coordinated complexes [Ti(NMe2)2(dbml)2] (3) and [Ti(NEt2)2(dbml)2] (4) are presented and discussed. The complexes are solids and the chemical and thermal characteristics of the complexes strongly depend on the substitution at the malonate ligand. While dpml containing complexes show a promising behaviour for classical MOCVD, dbml containing complexes seem to be more suitable for liquid injection-metal-organic chemical vapour deposition (LI-MOCVD). Based on its thermal characteristics, the most promising complex for thermal CVD, [Ti(NEt2)2(dpml)2] (2) was selected for preliminary MOCVD experiments, which indicate a good suitability for the deposition of TiO2 thin films.
... Govt. of India). One of us (A. Varade) thanks Dr. Latha Kumari and Vaibhav Varade (Physics De... more ... Govt. of India). One of us (A. Varade) thanks Dr. Latha Kumari and Vaibhav Varade (Physics Dept., IISc, India) for vital discussions regarding charge transport. One of us (A. Varade) would like to thank Prof. S. Sampath (Dept. ...
Equilibrium thermodynamic analysis has been applied to the low-pressure MOCVD process using manga... more Equilibrium thermodynamic analysis has been applied to the low-pressure MOCVD process using manganese acetylacetonate as the precursor. “CVD phase stability diagrams” have been constructed separately for the processes carried out in argon and oxygen ambient, depicting the compositions of the resulting films as functions of CVD parameters. For the process conduced in argon ambient, the analysis predicts the simultaneous deposition of MnO and elemental carbon in 1:3 molar proportion, over a range of temperatures. The analysis predicts also that, if CVD is carried out in oxygen ambient, even a very low flow of oxygen leads to the complete absence of carbon in the film deposited oxygen, with greater oxygen flow resulting in the simultaneous deposition of two different manganese oxides under certain conditions. The results of thermodynamic modeling have been verified quantitatively for low-pressure CVD conducted in argon ambient. Indeed, the large excess of carbon in the deposit is found to constitute a MnO/C nanocomposite, the associated cauliflower-like morphology making it a promising candidate for electrode material in supercapacitors. CVD carried out in oxygen flow, under specific conditions, leads to the deposition of more than one manganese oxide, as expected from thermodynamic analysis (and forming an oxide–oxide nanocomposite). These results together demonstrate that thermodynamic analysis of the MOCVD process can be employed to synthesize thin films in a predictive manner, thus avoiding the inefficient trial-and-error method usually associated with MOCVD process development. The prospect of developing thin films of novel compositions and characteristics in a predictive manner, through the appropriate choice of CVD precursors and process conditions, emerges from the present work.
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