Thickness evolution of the microstructure of si:h films in the amorphous-to-microcrystalline phase transition region

Authors

R. W. Collins, Pennsylvania State University
G. M. Ferreira, Pennsylvania State University
A. S. Ferlauto, Pennsylvania State University
R. J. Koval, Pennsylvania State University
J. M. Pearce, Pennsylvania State UniversityFollow
C. R. Wronski, Pennsylvania State University
M. M. Al-Jassim, National Renewable Energy Laboratory
K. M. Jones, National Renewable Energy Laboratory

Document Type

Conference Proceeding

Publication Date

12-1-2003

Volume

C

Journal

Proceedings of the 3rd World Conference on Photovoltaic Energy Conversion

First Page

2767

Last Page

2772

Abstract

Real time spectroscopic ellipsometry (RTSE) has been applied to develop deposition phase diagrams that describe the thickness evolution of the phase of hydrogenated silicon (Si:H) thin films. Such diagrams can be applied to establish optimization principles for the intrinsic (i-) layers incorporated into high performance solar cells based on amorphous Si:H (a-Si:H). The phase diagrams for the growth of Si:H on a-Si:H film substrates incorporate two transitions versus accumulated thickness, the first from the amorphous to the mixed-phase (amorphous + microcrystalline) growth regime [the a→(a+μc) transition] and the second from the mixed-phase to single-phase microcrystalline growth regime [the (a+μc)→μc transition]. Methods have been developed to extract the evolution of the volume fraction of microcrystalline Si:H (μc-Si:H) within the mixed-phase growth regime. Similar deposition phase diagrams have also been developed to optimize p-type Si:H layers for a-Si:H-based n-i-p and p-i-n cells.