Gas Phase and Surface Kinetic Processes in Hot-Wire Chemical Vapor Deposition

Holt, Jason K.; Swiatek, Maribeth; Goodwin, David G.; Atwater, Harry A.

doi:10.1557/proc-609-a6.2

Cited by 4 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There have been a number of recent reports [3][4][5][6] of the distribution of wire-desorbed radicals, following the early report by Doyle et al 7 Experiments conducted using similar detection schemes, such as vacuum ultraviolet photoionization mass spectrometry, have shown quite different results in some cases. 4,5 Whether these differences are due to the different histories of the wire used or differences in the reactor condition ͑e.g., amorphous silicon-coated walls͒ is unclear.…”

Section: Introductionmentioning

confidence: 99%

The aging of tungsten filaments and its effect on wire surface kinetics in hot-wire chemical vapor deposition

Holt

Swiatek

Goodwin

et al. 2002

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

Wire-desorbed radicals present during hot-wire chemical vapor deposition growth have been measured by quadrupole mass spectrometry. New wires produce Si as the predominant radical for temperatures above 1500 K, with a minor contribution from SiH 3 , consistent with previous measurements; the activation energy for the SiH 3 signal suggests its formation is catalyzed. Aged wires also produce Si as the predominant radical ͑above 2100 K͒, but show profoundly different radical desorption kinetics. In particular, the Si signal exhibits a high temperature activation energy consistent with evaporation from liquid silicon. The relative abundance of the other SiH x species suggests that heterogeneous pyrolysis of SiH 4 on the wire may be occurring to some extent. Chemical analysis of aged wires by Auger electron spectroscopy suggests that the aging process is related to the formation of a silicide at the surface, with silicon surface concentrations as high as 15 at. %. A limited amount ͑2 at. %͒ of silicon is observed in the interior as well, suggesting that diffusion into the wire occurs. Calculation of the relative rates for the various wire kinetic processes, coupled with experimental observations, reveals that silicon diffusion through the silicide is the slowest process, followed by Si evaporation, with SiH 4 decomposition being the fastest.

show abstract

Section: Introductionmentioning

confidence: 99%

The aging of tungsten filaments and its effect on wire surface kinetics in hot-wire chemical vapor deposition

Holt

Swiatek

Goodwin

et al. 2002

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to the SiH 3 homogeneous reaction SiH 2 is created, which at higher pressures may polymerize further to Si 3 H 4 . Holt et al [554] have performed Monte Carlo simulations to study gas phase and kinetic processes in HWCVD. They showed that under the conditions for obtaining device quality material SiH 3 is the most abundant species at the substrate.…”

Section: Ixd Deposition Modelmentioning

confidence: 99%

Methods of deposition of hydrogenated amorphous silicon for device applications

Sark

2002

Handbook of Thin Films

View full text Add to dashboard Cite

“…The silane (SiH 4 ), used as source gas, induces the formation of silicide (WSi x ) at the surface of the tungsten (W) wire employed as catalyzer. Moreover, the radical desorption kinetics from the filament profoundly change with silicide formation [6,7]. The aging of the catalyzer implies a low reproducibility of the deposited material quality.…”

Section: Introductionmentioning

confidence: 99%

Hot wire chemical vapor deposition: limits and opportunities of protecting the tungsten catalyzer from silicide with a cavity

et al. 2009

View full text Add to dashboard Cite

Hot Wire Chemical Vapor Deposition (HW-CVD) is one of the most promising techniques for depositing the intrinsic microcrystalline silicon layer for the production of micro-morph solar cells. However, the silicide formation at the colder ends of the tungsten wire drastically reduces the lifetime of the catalyzer, thus limiting its industrial exploitation. A simple but interesting strategy to decrease the silicide formation is to hide the electrical contacts of the catalyzer in a long narrow cavity which reduces the probability of the silane molecules to reach the colder ends of the wire. In this paper, the working mechanism of the cavity is elucidated. Measurements of the thickness profile of the silicon deposited in the internal walls of the cavity have been compared with those predicted using a simple diffusion model based on the assumption of Knudsen flow. A lifetime study of the 2 protected and unprotected wires has been carried out. The different mechanisms which determine the deterioration of the catalyzer have been identified and discussed.

show abstract

Gas Phase and Surface Kinetic Processes in Hot-Wire Chemical Vapor Deposition

Cited by 4 publications

References 8 publications

The aging of tungsten filaments and its effect on wire surface kinetics in hot-wire chemical vapor deposition

The aging of tungsten filaments and its effect on wire surface kinetics in hot-wire chemical vapor deposition

Methods of deposition of hydrogenated amorphous silicon for device applications

Hot wire chemical vapor deposition: limits and opportunities of protecting the tungsten catalyzer from silicide with a cavity

Contact Info

Product

Resources

About