Publication detail

Local optical and electric characteristics of solar cells

TOMÁNEK, P. ŠKARVADA, P. GRMELA, L.

Original Title

Local optical and electric characteristics of solar cells

Type

conference paper

Language

English

Original Abstract

Today photovoltaic cells are divided into two principal types: higher-efficiency but quite expensive crystalline silicon solar cells (either monocrystalline or multicrystalline), and lower-cost thin-film solar cells, usually composed of amorphous silicon, polycrystalline silicon, cadmium telluride, or copper indium gallium diselenide. In both cases their operation is based on a large-area pn junction. Their efficiency is generally limited by defects and impurities, which include grain boundaries, dislocations, and transition metals. A wide variety of defects can be formed in a silicon crystals during and after their growth. Some of defects arise on cell surface during its life-time such as scratches. These surface damages are origin of lower light-trapping efficiency. Many of defects do not cause cell malfunction, but generate local microplasmas, which are conductive and hence reduce overall cell efficiency. A number of defects of various kinds, some of them being of local character only, can not be observed with classical methods in such large-area junctions. Therefore a use of more precise scanning probe microscopes represents a novel approach to surface investigations with superresolving features. The paper presents results of experimental study of high resolution map of induced photocurrent and local electroluminescence in monocrystalline silicon solar cells. Photovoltaic solar cells are evaluated by I-V electric measurement, Far-field and Near-field Optical Beam Induced photocurrent (NOBIC), as well as by Scanning Near-field Optical Microscope (SNOM) topography and reflection. The correlation between reflection and transport characteristics indicates power of this diagnostic tool.

Keywords

solar cell, optical characteristics, electric characteristics, local measurement

Authors

TOMÁNEK, P.; ŠKARVADA, P.; GRMELA, L.

RIV year

2010

Released

1. 1. 2010

Publisher

SPIE

Location

Bellingham, USA

ISBN

978-0-8194-7671-5

Book

Ninth International Conference on Correlation Optics

ISBN

0277-786X

Periodical

Proceedings of SPIE

Year of study

7388

Number

7388

State

United States of America

Pages from

73880L1

Pages to

73880L9

Pages count

9