Design of ZnO:Al films with optimized surface texture for silicon thin-film solar cells

Michael Berginski; Bernd Rech; Jürgen Hüpkes; Helmut Stiebig; Matthias Wuttig

doi:10.1117/12.661667

12 May 2006 Design of ZnO:Al films with optimized surface texture for silicon thin-film solar cells

Michael Berginski, Bernd Rech, Jürgen Hüpkes, Helmut Stiebig, Matthias Wuttig

Proceedings Volume 6197, Photonics for Solar Energy Systems; 61970Y (2006) https://doi.org/10.1117/12.661667
Event: SPIE Photonics Europe, 2006, Strasbourg, France

Abstract

This study addresses the design of radio frequency (rf) magnetron sputtered aluminum doped zinc oxide (ZnO:Al) front contacts for silicon thin-film solar cells. Optimized films comprise high conductivity and transparency, as well as a surface topography trapping the light within the photovoltaically active layers. We have investigated the influence of the doping level of the target as well as the substrate temperature during sputter deposition on the ZnO:Al properties. The aluminum content in the target influences the transmission in the near infrared (NIR), the conductivity as well as the film growth of the ZnO:Al layer. The latter affects the surface topography which develops during wet-chemical etching in diluted hydrochloric acid. Depending on aluminum content in the target and heater temperature three different regimes of etching behavior have been identified. We have applied the ZnO:Al films as front contacts in thin-film silicon solar cells to study their light trapping ability. While high transparency is a prerequisite, the light trapping has been improved using front contacts with a surface topography consisting of relatively uniformly dispersed craters. We have identified low amount of target doping and high substrate temperatures as sputter parameters enabling high cell currents. Short-circuit current densities of up to 26.8 mA/cm² have been realized in μc-Si:H single junction cell with absorber layer thickness of 1.9 μm.

Citation Download Citation

Michael Berginski, Bernd Rech, Jürgen Hüpkes, Helmut Stiebig, and Matthias Wuttig "Design of ZnO:Al films with optimized surface texture for silicon thin-film solar cells", Proc. SPIE 6197, Photonics for Solar Energy Systems, 61970Y (12 May 2006); https://doi.org/10.1117/12.661667

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available