Requires Subscription: Photovoltaics International Archive

Solutions used in the texturization of monocrystalline silicon

Share on facebook
Facebook
Share on twitter
Twitter
Share on linkedin
LinkedIn
Share on reddit
Reddit
Share on email
Email

By Jose Ximello-Quiebras, Department of Physics, University of Konstanz; Johannes Junge, New Materials Group, Department of Physics, University of Konstanz; Sven Seren, Head of the New Materials Group, Department of Physics, University of Konstanz; Giso Hahn, Department of Physics, University of Konstanz; Ernst Epple, CTO, Lotus Systems GmbH

Texturization of (100) monocrystalline silicon (mono-Si) for solar cells is still an issue in the industrial production of standard screen-printed mono-Si solar cells. This fact is due to the properties of isopropyl alcohol (IPA), which is used together with potassium hydroxide (KOH) in the standard etching solution KOH-IPA (or used with sodium hydroxide NaOH in NaOH-IPA). The low boiling point of IPA (82.4°C) limits the etching temperature and thus the processing speed. Furthermore, KOH-IPA etching solution is very sensitive to the wafer pre-treatment characteristics of as-cut mono-Si wafers. Two ways to overcome these disadvantages are presented in this paper. The first approach involves the use of a high boiling alcohol (HBA) instead of IPA in the standard KOH-IPA etching solution. This allows higher etching temperatures to be used, without evaporation losses of the alcohol, but with reduced etching times. The second approach consists of using a closed etching bath in which vacuum (low-pressure) steps (i.e. pressure oscillations between atmospheric and below-atmospheric pressure) are achievable; in addition, a cooling system located on top of the etching bath allows the liquefaction of the evaporated IPA. The second texturing approach considerably decreases the etching time of mono-Si wafers. Examples of mono-Si wafers were textured using the new KOH-HBA etching solution and then processed into solar cells; the current-voltage results of the processed solar cells are presented.

L3dwLWNvbnRlbnQvdXBsb2Fkcy9sZWdhY3ktcHVibGljYXRpb24tcGRmcy80MDExMGY1OWE3LXNvbHV0aW9ucy11c2VkLWluLXRoZS10ZXh0dXJpemF0aW9uLW9mLW1vbm9jcnlzdGFsbGluZS1zaWxpY29uLnBkZg==

Published In

Photovoltaics International Archive
This sixteenth edition of Photovoltaics International marks four years of production of the quarterly journal. As always, our focus is on efficiency and quality improvement and cost reduction in manufacturing.

Read Next

Photovoltaics International Archive
Photovoltaics International Papers, PV Modules
With mature product offerings now available from several of the leading industrial PV equipment and tool manufacturers, and latest-generation ECAs available from suppliers, this article aims to provide important background information on ECAs, as well as give a brief overview of some of the challenges and cutting-edge developments in ECA-related PV applications.
Photovoltaics International Archive
Cell Processing, Photovoltaics International Papers
This paper reviews those associated fabrication technologies for the mass production of Ni/Cu-plated contacts. The technologies currently in use in the PV industry for plated contacts, as well as the developing technologies having high scaling-up potential, will be reviewed. In addition, the future requirements for plating metallization will be discussed.
Photovoltaics International Archive
Cell Processing, Photovoltaics International Papers
This paper discusses what is actually behind these announcements and how an evolutionary industry sector such as PVis becoming, it seems, decidedly revolutionary with large jumps in efficiency.
Photovoltaics International Archive
Cell Processing, Photovoltaics International Papers
This paper presents an analysis and the results of extensive simulations of the efficiency limits and roadmap to 25.5% of a tunnel oxide passivated contact (TOPCon) solar cell, on the basis of an efficiency level of 25.21% (designed area, identified by ISFH) achieved through three years of continuous technical optimization on a pilot line at Longi.
Photovoltaics International Archive
Cell Processing, Photovoltaics International Papers
The development of new ways of increasing the production throughput for passivated emitter and rear cells (PERCs), as the major solar cell technology in the global market, is an area of great interest to the PV community. This paper presents approaches for significantly increasing the throughput of PERC production processes. The main focus is on the tube furnace processes for the emitter formation and oxidation, with the introduction of the High Temperature Stack Oxidation (HiTSOx) approach. Additional approaches that are currently under investigation at Fraunhofer ISE for increasing the throughput for wet-chemical, printing and laser processes will also be briefly outlined.
Photovoltaics International Archive
Cell Processing, Photovoltaics International Papers
The holy grail of every solar cell producer is the creation of a lowcost interdigitated back-contact (IBC) solar cell with an efficiency greater than 25%, a goal that can be found in almost every roadmap presentation. In this paper it will be shown that we are not far away from achieving this target, since IBC devices, with different process complexities, are already in production at several companies.

Subscribe to Newsletter

Upcoming Events

Solar Media Events
June 14, 2022
Napa, USA
Solar Media Events
October 4, 2022
New York, USA