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Better control over the onset of microcrystallinity in fast-growing silicon network

Published online by Cambridge University Press:  03 March 2011

Sumita Mukhopadhyay
Affiliation:
Energy Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
Debajyoti Das
Affiliation:
Energy Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
Swati Ray*
Affiliation:
Energy Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
*
a) Address all correspondence to this author. e-mail: ersm@iacs.res.in
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Abstract

In view of obtaining a Si:H network at the onset of microcrystallinity at a high deposition rate, we have adopted an intelligent approach to find out a tricky plasma condition in radio frequency (rf) plasma-enhanced chemical vapordeposition that provides a better control on growth introducing retarded microcrystallization. The deposition parameter includes a combination of high electrical power applied to the (SiH4+H2)-plasma and high gas pressure in thereaction chamber. High rf power increases the number density of film-forming precursors as well as atomic H density in the plasma, which helps to increase thefilm deposition rate and to promote microcrystallinity, respectively. In addition,high pressure helps not only to increase the film-growth rate by producing a dense plasma but also retards the microcrystallization process by increasing significantlythe gas phase collision frequency and consequently reducing the effective reactivityof atomic H on the surface of a fast-growing Si:H network. A combination of high-power and high-pressure plasma conditions provides a reasonably wide rangeof H2 dilution to work with and better control in producing a Si:H network at theonset of microcrystallinity, while increasing the film-growth rate.

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Articles
Copyright
Copyright © Materials Research Society 2004

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References

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