Title :
Direct nm-Scale Spatial Mapping of Traps in CIGS
Author :
Paul, P.K. ; Cardwell, D.W. ; Jackson, C.M. ; Galiano, K. ; Aryal, K. ; Pelz, J.P. ; Marsillac, S. ; Ringel, S.A. ; Grassman, T.J. ; Arehart, A.R.
Author_Institution :
Ohio State Univ., Columbus, OH, USA
Abstract :
Nanometer-scale deep-level transient spectroscopy (nano-DLTS) is used to simultaneously map the spatial distribution of the EV + 0.47 eV trap in p-type Cu(In,Ga)Se2 with surface topography, providing a spatially resolved correlation between electrical traps with physical structure. It is demonstrated that the observed EV + 0.47 eV trap properties using nano-DLTS match those seen with conventional macroscopic device-scale DLTS measurements. Additionally, maps of the EV + 0.47 eV trap reveal that this trap is not uniformly distributed and is likely associated with specific grain boundary structures. The combined approach reveals overall trap impact from the local nanometer scale to the device (micrometer-centimeter) scale and correlation with physical structures on the nanometer-scale that can be broadly applied to any semiconductor material.
Keywords :
copper compounds; deep level transient spectroscopy; gallium compounds; grain boundaries; indium compounds; surface topography; ternary semiconductors; Cu(InGa)Se2; device scale; electrical traps; grain boundary structures; local nanometer scale; macroscopic device-scale DLTS measurements; nanometer-scale deep-level transient spectroscopy; overall trap impact; physical structures; semiconductor material; spatial trap distribution; spatially resolved correlation; surface topography; trap direct nanometer-scale spatial mapping; Capacitance; Photovoltaic cells; Semiconductor device measurement; Spatial resolution; Spectroscopy; Temperature measurement; Transient analysis; Cu(In; Ga)Se2 (CIGS); deep levels; nano-DLTS; thin-film solar cell;
Journal_Title :
Photovoltaics, IEEE Journal of
DOI :
10.1109/JPHOTOV.2015.2459971
