Evolution of Crystallinity in Mixed-Phase (a+μc)-Si:H as Determined by Real Time Spectroscopic Ellipsometry

2003 ◽  
Vol 762 ◽  
Author(s):  
A. S. Ferlauto ◽  
G. M. Ferreira ◽  
R.J. Koval ◽  
J.M. Pearce ◽  
C.R. Wronski ◽  
...  
Keyword(s):  
Real Time ◽  
Spectroscopic Ellipsometry ◽  
Vapor Deposition ◽  
Volume Fraction ◽  
Cone Angle ◽  
Chemical Vapor ◽  
Mixed Phase ◽  
Thin Film Solar Cells ◽  
Nucleation Density ◽  
Microcrystalline Silicon

AbstractThe ability to characterize the phase of the intrinsic (i) layers incorporated into amorphous silicon [a-Si:H] and microcrystalline silicon [μc-Si:H] thin film solar cells is critically important for cell optimization. In our research, a new method has been developed to extract the thickness evolution of the μc-Si:H volume fraction in mixed phase amorphous + microcrystalline silicon [(a+μc)-Si:H] i-layers. This method is based on real time spectroscopic ellipsometry measurements performed during plasma-enhanced chemical vapor deposition of the films. In the analysis, the thickness at which crystallites first nucleate from the a-Si:H phase can be estimated, as well as the nucleation density and microcrystallite cone angle. The results correlate well with structural and solar cell measurements.

Stress in Hydrogenated Microcrystalline Silicon Thin Films

1999 ◽  
Vol 557 ◽  
Author(s):  
D. Peiró ◽  
C. Voz ◽  
J. Bertomeu ◽  
J. Andreu ◽  
E. Martínez ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Vapor Deposition ◽  
Volume Fraction ◽  
Chemical Vapor ◽  
Hot Wire ◽  
X Ray Diffraction ◽  
Microcrystalline Silicon ◽  
X Ray ◽  
Silicon Thin Films ◽  
Abrupt Changes

AbstractHydrogenated microcrystalline silicon films have been obtained by hot-wire chemical vapor deposition (HWCVD) in a silane and hydrogen mixture at low pressure (<5 × 10-2 mbar). The structure of the samples and the residual stress were characterised by X- ray diffraction (XRD). Raman spectroscopy was used to estimate the volume fraction of the crystalline phase, which is in the range of 86 % to 98%. The stress values range between 150 and -140 MPa. The mechanical properties were studied by nanoindentation. Unlike monocrystalline wafers, there is no evidence of abrupt changes in the force-penetration plot, which have been attributed to a pressure-induced phase transition. The hardness was 12.5 GPa for the best samples, which is close to that obtained for silicon wafers.

Effect of Hydrogen Radical on Properties of Hydrogen in Hydrogenated Microcrystalline Silicon

2000 ◽  
Vol 609 ◽  
Author(s):  
Takashi Itoh ◽  
Noriyuki Yamana ◽  
Hiroki Inouchi ◽  
Norimitsu Yoshida ◽  
Hidekuni Harada ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Volume Fraction ◽  
Chemical Vapor ◽  
Hot Wire ◽  
Crystalline Volume Fraction ◽  
Microcrystalline Silicon ◽  
Integrated Intensity ◽  
Hydrogen Radical ◽  
Integrated Intensities

ABSTRACTHydrogenated microcrystalline silicon (μc-Si:H) films are prepared by hot-wire assisted plasma enhanced chemical vapor deposition, which controls the hydrogen radical density by filament temperatures, Tf, without changing other conditions. The effect of hydrogen radical on the properties of incorporated hydrogen into μc-Si:H films is studied using infrared absorption and gas effusion spectroscopies. The hydrogen concentration decreases with increasing Tf. The crystalline volume fraction, Xc, increases with Tf and shows a peak at Tf of 1850 °C. Integrated intensities of the modes near 2000 and 2100 cm-1 decrease with increasing Tf. Integrated intensity of the mode near 880 cm-1 shows almost same tendency of Xc. The effect of hydrogen radical on the properties of incorporated hydrogen into μc-Si:H films is discussed.

scholarly journals Structural Characterization of SiF4, SiH4 and H2 Hot-Wire-Grown Microcrystalline Silicon Thin Films with Large Grains

2001 ◽  
Vol 664 ◽  
Author(s):  
J. J. Gutierrez ◽  
C. E. Inglefield ◽  
C. P. An ◽  
M. C. DeLong ◽  
P. C. Taylor ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Vapor Deposition ◽  
Volume Fraction ◽  
Annealing Treatment ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Hot Wire ◽  
Microcrystalline Silicon ◽  
Crystal Volume

ABSTRACTIn this paper, we present a comprehensive study of microcrystalline silicon thin film samples deposited by a novel growth process intended to maximize their grain size and crystal volume fraction. Using Atomic Force Microscopy, Raman spectroscopy, and x ray diffraction the structural properties of these samples were characterized qualitatively and quantitatively. Samples were grown using a Hot-Wire Chemical Vapor Deposition process with or without a post-growth hot-wire annealing treatment. During Hot-Wire Chemical Vapor Deposition, SiF4 is used along with SiH4 and H2 to grow the thin films. After growth, some samples received an annealing treatment with only SiF4 and H2 present. These samples were compared to each other in order to determine the deposition conditions that maximize grain size. Large microcrystalline grains were found to be aggregates of much smaller crystallites whose size is nearly independent of deposition type and post-annealing treatment. Thin films deposited using the deposition process with SiF4 partial flow rate of 2 sccm and post-growth annealing treatment had the largest aggregate grains ∼.5 µm and relatively high crystal volume fraction.

Real time spectroscopic ellipsometry characterization of the nucleation of diamond by filament‐assisted chemical vapor deposition

1992 ◽  
Vol 71 (10) ◽  
pp. 5287-5289 ◽  
Author(s):  
R. W. Collins ◽  
Yue Cong ◽  
H. V. Nguyen ◽  
Ilsin An ◽  
K. Vedam ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Real Time ◽  
Spectroscopic Ellipsometry ◽  
Vapor Deposition ◽  
Chemical Vapor
Sign in / Sign up

Export Citation Format

Share Document