Influence of the total gas flow rate on high rate growth microcrystalline silicon films and solar cells

2009 ◽  
Vol 18 (8) ◽  
pp. 3563-3567 ◽  
Author(s):  
Han Xiao-Yan ◽  
Hou Guo-Fu ◽  
Zhang Xiao-Dan ◽  
Wei Chang-Chun ◽  
Li Gui-Jun ◽  
...  
2006 ◽  
Vol 15 (5) ◽  
pp. 1110-1113 ◽  
Author(s):  
Gao Yan-Tao ◽  
Zhang Xiao-Dan ◽  
Zhao Ying ◽  
Sun Jian ◽  
Zhu Feng ◽  
...  

2015 ◽  
Vol 1734 ◽  
Author(s):  
Kento Nakanishi ◽  
Jun Otsuka ◽  
Masanori Hiratsuka ◽  
Chen Chung Du ◽  
Akira Shirakura ◽  
...  

ABSTRACTDiamond-like carbon (DLC) has widespread attention as a new material for its application to thin film solar cells and other semiconducting devices. DLC can be produced at a lower cost than amorphous silicon, which is utilized for solar cells today. However, the electrical properties of DLC are insufficient for this purpose because of many dangling bonds in DLC. To solve this problem, we investigated the effects of the fluorine incorporation on the structural and electrical properties of DLC.We prepared five kinds of fluorinated DLC (F-DLC) thin film with different amounts of fluorine. Films were deposited by the radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) method. C6H6 and C6HF5 were used as source gases. The total gas flow rate was constant and the gas flow rate ratio R (=C6H6 / (C6H6 + C6HF5)) was changed from 0 to 1 in 0.25 ratio steps. We also prepared nitrogen doped DLC (F-DLC) on p-Si using N2 gas as a doping gas to form nitrogen doped DLC (F-DLC) / p-Si heterojunction diodes.X-ray photoelectron spectroscopy (XPS) showed that fluorine concentration in the DLC films was controlled. Moreover, the XPS analysis of the C1s spectrum at R=2/4 showed the presence of CF bonding. At R=1, CF2 bonding was observed in addition to CF bonding. The sheet resistivity of the films changed from 3.07×1012 to 4.86×109 Ω. The minimum value was obtained at R=2/4. The current-voltage characteristics indicated that nitrogen doped F-DLC of 2/4 and p-Si heterojunction diode exhibited the best rectification characteristics and its energy conversion efficiency had been maximized. This is because of a decrease of dangling bonds density by ESR analysis and an increase of sp2 structures by Raman analysis. When the fluorine is over certain content, the sheet resistivity increases because chain structures become larger, which is due to the CF2 bonding in F-DLC prevents ring structures. Many C2F4 species were observed and it may become precursors of the chain structure domains, such as (CF2)n.In this study, we revealed effects of fluorine incorporation on DLC and succeeded in increasing its conductivity and improving rectification characteristics of DLC/ p-Si hetero-junction diodes. Our results indicate that DLC fluorination is effective for the semiconducting material, such as solar cell applications.


2014 ◽  
Vol 47 (6) ◽  
pp. 478-482 ◽  
Author(s):  
Satoshi Nishida ◽  
Hiroshi Muta ◽  
Shizuma Kuribayashi
Keyword(s):  
Gas Flow ◽  

2001 ◽  
Vol 664 ◽  
Author(s):  
I. Ferreira ◽  
F. Braz Fernandes ◽  
P. Vilarinho ◽  
E. Fortunato ◽  
R. Martins

ABSTRACTIn this work, we present the properties of n-type silicon films obtained by hot wire plasma assisted technique produced at different rf power and gas flow rate. The films were produced at a filament temperature of 2000°C and the rf power was varied from 0W to 200W while gas flow rate was varied from 15 to 100sccm keeping rf power at 50W. In this flow rate range, the growth rate of the films varied from 5Å/s to 250Å/s and the corresponding electrical room dark conductivity varied from 10−2 to 10(Ωcm)-1. On the other hand, we observed that the electrical conductivity increased from 2 to 6(Ωcm)-1, and the Hall mobility from 0.1 to 2cm2/V.s as rf power change from 0W to 200W. The infrared, EDS and XPS analyses revealed the existence of oxygen incorporation, which is not related to post-deposition oxidation. The X-ray diffraction and [.proportional]Raman data show the presence of Si crystals in the films structure and the SEM micrographs reveal a granular surface morphology with grain sizes lower than 60nm.


Author(s):  
B.S. Soroka ◽  
V.V. Horupa

Natural gas NG consumption in industry and energy of Ukraine, in recent years falls down as a result of the crisis in the country’s economy, to a certain extent due to the introduction of renewable energy sources along with alternative technologies, while in the utility sector the consumption of fuel gas flow rate enhancing because of an increase the number of consumers. The natural gas is mostly using by domestic purpose for heating of premises and for cooking. These items of the gas utilization in Ukraine are already exceeding the NG consumption in industry. Cooking is proceeding directly in the living quarters, those usually do not meet the requirements of the Ukrainian norms DBN for the ventilation procedures. NG use in household gas stoves is of great importance from the standpoint of controlling the emissions of harmful components of combustion products along with maintenance the satisfactory energy efficiency characteristics of NG using. The main environment pollutants when burning the natural gas in gas stoves are including the nitrogen oxides NOx (to a greater extent — highly toxic NO2 component), carbon oxide CO, formaldehyde CH2O as well as hydrocarbons (unburned UHC and polyaromatic PAH). An overview of environmental documents to control CO and NOx emissions in comparison with the proper norms by USA, EU, Russian Federation, Australia and China, has been completed. The modern designs of the burners for gas stoves are considered along with defining the main characteristics: heat power, the natural gas flow rate, diameter of gas orifice, diameter and spacing the firing openings and other parameters. The modern physical and chemical principles of gas combustion by means of atmospheric ejection burners of gas cookers have been analyzed from the standpoints of combustion process stabilization and of ensuring the stability of flares. Among the factors of the firing process destabilization within the framework of analysis above mentioned, the following forms of unstable combustion/flame unstabilities have been considered: flashback, blow out or flame lifting, and the appearance of flame yellow tips. Bibl. 37, Fig. 11, Tab. 7.


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