Description: Control of plasma process instabilities during thin silicon film deposition

This title appears in the Scientific Report : 2009

Control of plasma process instabilities during thin silicon film deposition

Fourier transform infrared absorption spectroscopy (FTIR), optical emission spectroscopy (OES), self-bias voltage and plasma impedance controls were applied as in situ process diagnostics during the deposition of amorphous silicon thin-films. The diagnostic abilities of OES and FTIR are compared. Th...

Personal Name(s):	Hrunski, D.
	Grählert, W. / Beese, H. / Kilper, T. / Gordijn, A. / Appenzeller, W.
Contributing Institute:	Photovoltaik; IEF-5
Published in:	Thin solid films, 517 (2009) S. 4188 - 4191
Imprint:	Amsterdam [u.a.] Elsevier 2009
Physical Description:	4188 - 4191
DOI:	10.1016/j.tsf.2009.02.003
Document Type:	Journal Article
Research Program:	Erneuerbare Energien
Series Title:	Thin Solid Films 517
Subject (ZB):	J PECVD Thin silicon films Large-area deposition Process instabilities
	Publikationsportal JuSER

Please use the identifier: http://dx.doi.org/10.1016/j.tsf.2009.02.003 in citations.

Fourier transform infrared absorption spectroscopy (FTIR), optical emission spectroscopy (OES), self-bias voltage and plasma impedance controls were applied as in situ process diagnostics during the deposition of amorphous silicon thin-films. The diagnostic abilities of OES and FTIR are compared. The FTIR in-situ direct measurement of silane concentration in exhaust line is more precise than OES control. All in situ process diagnostics clearly indicates the inconsistency of plasma properties and therefore of deposition conditions. The drifts are comparable with the film deposition time. The FTIR measurement of reactant concentration in the process chamber evidence that the strong silane concentration drop (about 50%) in a plasma is the cause of the short-term drift of OES signals (SiH* emission), plasma impedance and self-bias voltage signals. The influences of the deposition chamber geometry and technological parameters on process drifts are considered. The decrease of the gas residence time in the reactor leads to a decrease of Initial Transient State phenomena. Finally, the improvement of solar cell performance based on thin silicon films is demonstrated when drifts are reduced. (C) 2009 Elsevier B.V. All rights reserved.