Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry

Nikolas J. Podraza, Jing Li, Christopher R. Wronski, Mark W. Horn, Elizabeth C. Dickey, Robert W. Collins

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Hydrogenated silicon (Si:H) and silicon-germanium alloy (Si 1-x-Ge x:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH 4 and GeH 4 and measured during growth using real time spectroscopic ellipsometry (RTSE). A two-layer virtual interface analysis has been applied to study the structural evolution of Si:H films prepared in multistep processes utilizing alternating layers of high and low H 2-dilution materials, which have been designed to produce predominantly amorphous silicon (a-Si:H) films with a controlled distribution of microcrystallites. The compositional evolution of alloy-graded a-Si 1-x-iGe xH has been studied as well using similar methods. In each study, the depth profile of the microcrystalline silicon (μc-Si:H) content,f μc, or the Ge content, x, has been extracted. Additionally, RTSE has been used to monitor post-deposition exposure of a-Si:H, a-Si 1-xGe x:H, and a-Ge:H films to hydrogen plasmas in situ in order to study the sub-surface modification and etching that would be anticipated when a highly H 2-diluted layer is deposited on a layer prepared with lower dilution. These analyses provide guidance for enhancing the performance of Si:H based solar cells through controlled fractions of microcrystallites in bulk amorphous i-layer materials using modulated H 2 dilution, through controlled bandgap profiling using compositionally graded a-Si 1-xGe x:H, and through a better understanding of the modification of underlying layers during the deposition of subsequent layers in multilayer stacks.

Original languageEnglish (US)
Title of host publicationAmorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008
Pages253-258
Number of pages6
StatePublished - Dec 1 2008
Event2008 MRS Spring Meeting - San Francisco, CA, United States
Duration: Mar 24 2008Mar 28 2008

Publication series

NameMaterials Research Society Symposium Proceedings
Volume1066
ISSN (Print)0272-9172

Other

Other2008 MRS Spring Meeting
CountryUnited States
CitySan Francisco, CA
Period3/24/083/28/08

Fingerprint

Spectroscopic ellipsometry
Dilution
ellipsometry
Thin films
Hydrogen
thin films
Microcrystalline silicon
dilution
Silicon
Plasma enhanced chemical vapor deposition
Amorphous silicon
Surface treatment
Etching
Solar cells
Multilayers
Energy gap
Plasmas
germanium alloys
silicon alloys
hydrogen plasma

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Podraza, N. J., Li, J., Wronski, C. R., Horn, M. W., Dickey, E. C., & Collins, R. W. (2008). Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry. In Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008 (pp. 253-258). (Materials Research Society Symposium Proceedings; Vol. 1066).
Podraza, Nikolas J. ; Li, Jing ; Wronski, Christopher R. ; Horn, Mark W. ; Dickey, Elizabeth C. ; Collins, Robert W. / Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry. Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008. 2008. pp. 253-258 (Materials Research Society Symposium Proceedings).
@inproceedings{19ad23b2bb91414c80bd57f47c0df441,
title = "Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry",
abstract = "Hydrogenated silicon (Si:H) and silicon-germanium alloy (Si 1-x-Ge x:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH 4 and GeH 4 and measured during growth using real time spectroscopic ellipsometry (RTSE). A two-layer virtual interface analysis has been applied to study the structural evolution of Si:H films prepared in multistep processes utilizing alternating layers of high and low H 2-dilution materials, which have been designed to produce predominantly amorphous silicon (a-Si:H) films with a controlled distribution of microcrystallites. The compositional evolution of alloy-graded a-Si 1-x-iGe xH has been studied as well using similar methods. In each study, the depth profile of the microcrystalline silicon (μc-Si:H) content,f μc, or the Ge content, x, has been extracted. Additionally, RTSE has been used to monitor post-deposition exposure of a-Si:H, a-Si 1-xGe x:H, and a-Ge:H films to hydrogen plasmas in situ in order to study the sub-surface modification and etching that would be anticipated when a highly H 2-diluted layer is deposited on a layer prepared with lower dilution. These analyses provide guidance for enhancing the performance of Si:H based solar cells through controlled fractions of microcrystallites in bulk amorphous i-layer materials using modulated H 2 dilution, through controlled bandgap profiling using compositionally graded a-Si 1-xGe x:H, and through a better understanding of the modification of underlying layers during the deposition of subsequent layers in multilayer stacks.",
author = "Podraza, {Nikolas J.} and Jing Li and Wronski, {Christopher R.} and Horn, {Mark W.} and Dickey, {Elizabeth C.} and Collins, {Robert W.}",
year = "2008",
month = "12",
day = "1",
language = "English (US)",
isbn = "9781605110363",
series = "Materials Research Society Symposium Proceedings",
pages = "253--258",
booktitle = "Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008",

}

Podraza, NJ, Li, J, Wronski, CR, Horn, MW, Dickey, EC & Collins, RW 2008, Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry. in Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008. Materials Research Society Symposium Proceedings, vol. 1066, pp. 253-258, 2008 MRS Spring Meeting, San Francisco, CA, United States, 3/24/08.

Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry. / Podraza, Nikolas J.; Li, Jing; Wronski, Christopher R.; Horn, Mark W.; Dickey, Elizabeth C.; Collins, Robert W.

Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008. 2008. p. 253-258 (Materials Research Society Symposium Proceedings; Vol. 1066).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

TY - GEN

T1 - Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry

AU - Podraza, Nikolas J.

AU - Li, Jing

AU - Wronski, Christopher R.

AU - Horn, Mark W.

AU - Dickey, Elizabeth C.

AU - Collins, Robert W.

PY - 2008/12/1

Y1 - 2008/12/1

N2 - Hydrogenated silicon (Si:H) and silicon-germanium alloy (Si 1-x-Ge x:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH 4 and GeH 4 and measured during growth using real time spectroscopic ellipsometry (RTSE). A two-layer virtual interface analysis has been applied to study the structural evolution of Si:H films prepared in multistep processes utilizing alternating layers of high and low H 2-dilution materials, which have been designed to produce predominantly amorphous silicon (a-Si:H) films with a controlled distribution of microcrystallites. The compositional evolution of alloy-graded a-Si 1-x-iGe xH has been studied as well using similar methods. In each study, the depth profile of the microcrystalline silicon (μc-Si:H) content,f μc, or the Ge content, x, has been extracted. Additionally, RTSE has been used to monitor post-deposition exposure of a-Si:H, a-Si 1-xGe x:H, and a-Ge:H films to hydrogen plasmas in situ in order to study the sub-surface modification and etching that would be anticipated when a highly H 2-diluted layer is deposited on a layer prepared with lower dilution. These analyses provide guidance for enhancing the performance of Si:H based solar cells through controlled fractions of microcrystallites in bulk amorphous i-layer materials using modulated H 2 dilution, through controlled bandgap profiling using compositionally graded a-Si 1-xGe x:H, and through a better understanding of the modification of underlying layers during the deposition of subsequent layers in multilayer stacks.

AB - Hydrogenated silicon (Si:H) and silicon-germanium alloy (Si 1-x-Ge x:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH 4 and GeH 4 and measured during growth using real time spectroscopic ellipsometry (RTSE). A two-layer virtual interface analysis has been applied to study the structural evolution of Si:H films prepared in multistep processes utilizing alternating layers of high and low H 2-dilution materials, which have been designed to produce predominantly amorphous silicon (a-Si:H) films with a controlled distribution of microcrystallites. The compositional evolution of alloy-graded a-Si 1-x-iGe xH has been studied as well using similar methods. In each study, the depth profile of the microcrystalline silicon (μc-Si:H) content,f μc, or the Ge content, x, has been extracted. Additionally, RTSE has been used to monitor post-deposition exposure of a-Si:H, a-Si 1-xGe x:H, and a-Ge:H films to hydrogen plasmas in situ in order to study the sub-surface modification and etching that would be anticipated when a highly H 2-diluted layer is deposited on a layer prepared with lower dilution. These analyses provide guidance for enhancing the performance of Si:H based solar cells through controlled fractions of microcrystallites in bulk amorphous i-layer materials using modulated H 2 dilution, through controlled bandgap profiling using compositionally graded a-Si 1-xGe x:H, and through a better understanding of the modification of underlying layers during the deposition of subsequent layers in multilayer stacks.

UR - http://www.scopus.com/inward/record.url?scp=62949151601&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=62949151601&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:62949151601

SN - 9781605110363

T3 - Materials Research Society Symposium Proceedings

SP - 253

EP - 258

BT - Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008

ER -

Podraza NJ, Li J, Wronski CR, Horn MW, Dickey EC, Collins RW. Analysis of compositionally and structurally graded Si:H and Si 1-xGe x:H thin films by real time spectroscopic ellipsometry. In Amorphous and Polycrystalline Thin-Film Silicon Science and Technology - 2008. 2008. p. 253-258. (Materials Research Society Symposium Proceedings).