Influence of Power on the Microstructure and Optical Properties of Microcrystalline Si Films

2014 ◽  
Vol 1016 ◽  
pp. 305-308
Author(s):  
Hua Cheng ◽  
Feng Jiang ◽  
Chang Zheng Ma ◽  
Kuo Jiang

Microcrystalline silicon films were deposited using Ar diluted SiH4 gaseous mixture by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD). The effects of power on microstrcture and optical properties of microcrystalline silicon films were investigated. The results show that, with the increasing of the power, the crystallinity increased, but the concentration of hydrogen decreased monotonously. Furthermore, the absorption coefficient of the films increased monotonously, and the optical bandgap changed from 1.89eV to 1.75eV with the microwave power ranging from 400 W to 650W.

1999 ◽  
Vol 593 ◽  
Author(s):  
Lih-Hsiung Chan ◽  
Wei-Zen Chou ◽  
Lih-Hsin Chou

ABSTRACTHydrogenated amorphous silicon carbide films (a -SiC:H) were prepared from CH4, SiH4, and Ar mixtures by Electron Cyclotron Resonance Plasma Chemical Vapor Deposition (ECR PCVD). The deposition of the thin films was proceeded with the following optimized conditions; microwave power: 900W, Ar flux : 90sccm, and total flux: 113.4 sccm. The substrate temperature was around 100∼120°C during deposition. For comparisons, the relative flux ratio of methane to silane was varied to produce thin films of different compositions to investigate the relationships between the associated compositions of films and their corresponding microstructures and optical properties. Moreover, both film's microstructures and their optical properties were analyzed to find out as to how they are interrelated. Furthermore, the surface morphology and amorphous microstructures were confirmed by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), respectively. And, x-ray Photoelectron Spectroscopy (XPS) was employed to study the relative atomic ratio of C to Si along with the bonding conditions in the thin films. Finally, the Hydrogen concentration and the amounts of C-H and Si-H bonds were determined by Fourier transform infrared spectroscopy(FTIR), while the optical properties were measured by optical spectrophotometer.


2017 ◽  
Vol 895 ◽  
pp. 28-32 ◽  
Author(s):  
Hua Cheng ◽  
Di Wang ◽  
Feng Li Li

Micro-Si films were deposited using Ar diluted SiH4 gaseous mixture by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD). The effects of the substrate temperature on microstructure and electrical conductivity of micro-Si film were investigated. The results show that, with the increasing of substrate temperature, crystallinity and grain size increased monotonously, of which a competing balance would determine the electrical conductivity of micro-Si films. Based on these results, relatively small grain size and appropriate crystallinity would be beneficial to improve the electrical properties of micro-Si films.


1996 ◽  
Vol 452 ◽  
Author(s):  
I. Beckers ◽  
E. Conrad ◽  
P. Müller ◽  
N. H. Nickel ◽  
I. Sieber ◽  
...  

AbstractMicrocrystalline silicon (μc-Si) films were prepared by electron cyclotron resonance assisted chemical vapor deposition (ECRCVD) using helium, argon and hydrogen dilution. The crystalline fraction was estimated from Raman backscattering spectra and scanning electron-microscopy (SEM) was used to obtain information on roughness and homogeneity of the films. For hydrogen dilution the highest crystallinity (Xc = 85 %) occurs at a ratio of ΔH = [H2]/([H2]+[SiH4])= 0.98. At the same time the deposition rate decreases continuously with increasing H2 dilution. These results are consistent with the idea that H etching promotes the growth of μc-Si. At ΔH > 0.98 a Xc decreases due to a H mediated transition of small crystallites into amorphous tissue. The implications of these results for the growth mechanisms are discussed.


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