Amorphous hydrogenated silicon nitride thin films a-SiN<sub>x</sub>:H (abbreviated later by SiN<sub>x</sub>) were deposited by Electron Cyclotron Resonance plasma enhanced chemical vapor deposi...Amorphous hydrogenated silicon nitride thin films a-SiN<sub>x</sub>:H (abbreviated later by SiN<sub>x</sub>) were deposited by Electron Cyclotron Resonance plasma enhanced chemical vapor deposition method (ECR-PECVD). By changing ratio of gas flow (R = NH<sub>3</sub>/SiH<sub>4</sub>) in the reactor chamber different stoichiometric layers x = [N]/[Si] ([N] and [Si] atomic concentrations) are successfully deposited. Part of the obtained films has subsequently undergone rapid thermal annealing RTA (800°C/1 s) using halogen lamps. Optical and structural characterizations are then achieved by spectroscopic ellipsometry (SE), ion beam analysis and infrared absorption techniques. The SE measurements show that the tuning character of their refractive index n(λ) with stoichiometry x and their non-absorption properties in the range of 250 - 850 nm expect for Si-rich SiN<sub>x</sub> films in the ultraviolet UV range. The stoichiometry x and its depth profile are determined by Rutherford backscattering spectrometry (RBS) while the hydrogen profile (atomic concentration) is determined by Elastic Recoil Detection Analysis (ERDA). Vibrational characteristics of the Si-N, Si-H and N-H chemical bonds in the silicon nitride matrix are investigated by infrared absorption. An atomic hydrogen fraction ranging from 12% to 22% uniformly distributed as evaluated by ERDA is depending inversely on the stoichiometry x ranging from 0.34 to 1.46 as evaluated by RBS for the studied SiN<sub>x</sub> films. The hydrogen loss after RTA process and its out-diffusion depend strongly on the chemical structure of the films and less on the initial hydrogen concentration. A large hydrogen loss was noted for non-thermally stable Si-rich SiNx films. Rich nitrogen films are less sensitive to rapid thermal process.展开更多
In this paper, polycrystalline silicon films were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition （ECR-PECVD） using SiH4/Ar and SiH4/H2 gaseous mixture. Effects of argon flow rate...In this paper, polycrystalline silicon films were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition （ECR-PECVD） using SiH4/Ar and SiH4/H2 gaseous mixture. Effects of argon flow rate on the deposition efficiency and the film property were investigated by comparing with H2. The results indicated that the deposition rate of using Ar as discharge gas was 1.5-2 times higher than that of using H2, while the preferred orientations and the grain sizes of the films were analogous. Film crystallinity increased with the increase of Ar flow rate. Optimized flow ratio of SiH4 to Ar was obtained as F（SiH4）： F（Ar）=10：70 for the highest deposition rate.展开更多
文摘Amorphous hydrogenated silicon nitride thin films a-SiN<sub>x</sub>:H (abbreviated later by SiN<sub>x</sub>) were deposited by Electron Cyclotron Resonance plasma enhanced chemical vapor deposition method (ECR-PECVD). By changing ratio of gas flow (R = NH<sub>3</sub>/SiH<sub>4</sub>) in the reactor chamber different stoichiometric layers x = [N]/[Si] ([N] and [Si] atomic concentrations) are successfully deposited. Part of the obtained films has subsequently undergone rapid thermal annealing RTA (800°C/1 s) using halogen lamps. Optical and structural characterizations are then achieved by spectroscopic ellipsometry (SE), ion beam analysis and infrared absorption techniques. The SE measurements show that the tuning character of their refractive index n(λ) with stoichiometry x and their non-absorption properties in the range of 250 - 850 nm expect for Si-rich SiN<sub>x</sub> films in the ultraviolet UV range. The stoichiometry x and its depth profile are determined by Rutherford backscattering spectrometry (RBS) while the hydrogen profile (atomic concentration) is determined by Elastic Recoil Detection Analysis (ERDA). Vibrational characteristics of the Si-N, Si-H and N-H chemical bonds in the silicon nitride matrix are investigated by infrared absorption. An atomic hydrogen fraction ranging from 12% to 22% uniformly distributed as evaluated by ERDA is depending inversely on the stoichiometry x ranging from 0.34 to 1.46 as evaluated by RBS for the studied SiN<sub>x</sub> films. The hydrogen loss after RTA process and its out-diffusion depend strongly on the chemical structure of the films and less on the initial hydrogen concentration. A large hydrogen loss was noted for non-thermally stable Si-rich SiNx films. Rich nitrogen films are less sensitive to rapid thermal process.
文摘In this paper, polycrystalline silicon films were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition （ECR-PECVD） using SiH4/Ar and SiH4/H2 gaseous mixture. Effects of argon flow rate on the deposition efficiency and the film property were investigated by comparing with H2. The results indicated that the deposition rate of using Ar as discharge gas was 1.5-2 times higher than that of using H2, while the preferred orientations and the grain sizes of the films were analogous. Film crystallinity increased with the increase of Ar flow rate. Optimized flow ratio of SiH4 to Ar was obtained as F（SiH4）： F（Ar）=10：70 for the highest deposition rate.
