Abstract
Local electrical transport measurements with scanning probe microscopy on polycrystalline (PX) p-CuInSe2 and p-Cu(In,Ga)Se2 films show that the photovoltaic and dark currents for bias voltages smaller than 1 V flow mainly through grain boundaries (GBs), indicating inversion at the GBs. Photocurrent for higher bias flows mainly via the grains. Based on these results and our finding of ∼100 meV GB band bending we deduce the potential landscape around the GBs. We suggest that high grain material quality, leading to large carrier mobilities, and electron-hole separation at the GBs, by chemical and electrical potential gradients, result in the high performance of these PX solar cells.
Original language | English |
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Pages (from-to) | 85-90 |
Number of pages | 6 |
Journal | Solar Energy Materials and Solar Cells |
Volume | 91 |
Issue number | 1 |
DOIs | |
State | Published - 5 Jan 2007 |
Externally published | Yes |
Keywords
- CIGS
- CIS
- Conductive AFM
- Grain boundaries
- Solar cell
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films