Hydrogenated-amorphous carbon nitride films formed from the dissociative excitation reaction of CH3CN with the microwave-discharge flow of Ar: Correlation of the [N]/([N]+[C]) ratio with the relative number densities of the CH(A2Δ) and CN(B2Σ+) states

Abstract

Electron cyclotron resonance deposition, structure, and properties of oxygen incorporated hydrogenated diamondlike amorphous carbon films J. Appl. Phys. 96, 5456 (2004); 10.1063/1.1804624 Amorphous silicon nitride films of different composition deposited at room temperature by pulsed glow discharge plasma immersion ion implantation and deposition High-resolution optical emission spectra of the CN(B 2 ⌺ ϩ -X 2 ⌺ ϩ ) and CH(A 2 ⌬ -X 2 ⌸) transitions were observed in the dissociative excitation reaction of CH 3 CN with the microwave-discharge flow of Ar. The H 2 O molecules contained in the starting materials and/or adsorbed on the wall of the apparatus were removed by using P 2 O 5 as a desiccant. The pressure of Ar, P Ar , was in the range of 0.1-0.8 Torr. From the simulation analysis of the observed spectra, the ratio of the concentrations of the CH(A 2 ⌬) and CN(B 2 ⌺ ϩ ) states, N CH(A) /N CN(B) , was determined as 0.09-0.41. It was indicated that the CN(B 2 ⌺ ϩ ) state was formed via the ion-electron recombination as well as the energy transfer from the metastable state of Ar. Based on the correlation between the N CH(A) /N CN(B) and ͓N͔/͓͑N͔ϩ͓C͔͒ ratios reported in the system without desiccation ͓Jpn. J. Appl. Phys. 40, 332 ͑2001͔͒, the ͓N͔/͓͑N͔ϩ͓C͔͒ ratio in the desiccated system was predicted to be Ϸ0.18. The hydrogenated-amorphous carbon nitride films prepared under the conditions of P Ar ϭ0.1, 0.4, 0.6, and 0.8 Torr were characterized by the Rutherford backscattering ͑RBS͒ analysis and the Fourier transform infrared ͑FTIR͒ spectroscopy. The observed ͓N͔/͓͑N͔ϩ͓C͔͒ ratios of the films were in the range of 0.17-0.21, being in good agreement with the above prediction. The structure of the films was independent of P Ar . The observed correlation between the N CH(A) /N CN(B) and ͓N͔/͓͑N͔ϩ͓C͔͒ ratios can be rationalized by the consideration that the relative concentrations of the CH(A 2 ⌬) and CN(B 2 ⌺ ϩ ) states and those of the precursor free radicals of the films are supposed to originate commonly to the relative concentrations of the active species of the discharge flow of Ar.

CN Surface Interactions and Temperature-Dependent Film Growth During Plasma Deposition of Amorphous, Hydrogenated Carbon Nitride

“…Consequently, the underlying chemical processes are often obscured. Concerted attempts to understand the fundamental gas, surface, and interface chemistry that dominates a-C:N:H deposition are relatively few, ,,– and the incorporation of nitrogen remains poorly understood. Here, we have employed CH 3 CN as a single-source precursor to alleviate some of these issues and to help elucidate chemical mechanisms for a-C:N:H PECVD.…”

Deposition of Amorphous CNx Materials in BrCN Plasmas: Exploring Adhesion Behavior as an Indicator of Film Properties

“…The possibility of milder ion bombardment conditions in BrCN plasmas may be justified based on the presence of electronegative Br. This is illustrated by the work of Ito and co-workers, who reported dramatic decreases in electron density upon the addition of BrCN to Ar discharges . Thus, if atomic Br scavenges free electrons, the ensuing decrease in electron density could be accompanied by decreases in the positive ion density and/or sheath potential, leading to a lower energy flux at the surface.…”

Production of CH(A2Δ) radicals from the dissociative excitation reaction of C2H2with microwave discharge flow of Ar

“…The apparatus was essentially the same as that used in our previous studies. 25,29) It consisted of a stainless-steel chamber, a quartz window (W) for extracting the optical emission or LIF, a Pyrex-glass discharge tube (D) set at the upper part of the chamber, and a stainless-steel nozzle (N) whose tip was placed ≈5 mm downstream of that of the discharge tube. The inner diameter of the chamber was 101.6 mm.…”

“…The outline of the method used to identify the dominant active species of Ar plasma is as follows. [23][24][25][26][27][28][29][30][31] The density of Ar( 3 P 0 ) atoms, n M , is measured by the laser-induced fluorescence (LIF) spectroscopy of the 3 P 1 -3 P 0 transition whose intensity is calibrated against the Rayleigh scattering intensity of neutral Ar. The density n e and temperature T e of free electrons are measured with an electrostatic probe.…”