Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of efficiency limiting processes in thin film Cu(In,Ga)(S,Se)2
  electrodeposited solar cells   Electrodeposited thin film cells have been fabricated with record-breaking
efficiencies of 11.4%. This presentation examines conversion mechanisms in
cells with a focus on the effect of CdS buffer layers using a range of
complementary tools. Dark currents (IVs) are well described by series and
parallel resistances, and two dominant recombination mechanisms represented by
parallel diodes. Measurements of IV as a function of temperature (IVT) allow
extraction of activation energies corresponding to these processes and indicate
their spatial position. Admittance spectroscopy (AS) gives an independent
estimate of the same energies, and yields values of the defect densities of
states in the forbidden gap. Two dominant levels are apparent, confirming the
validity of the IV analysis. Spectral response (QE) measurements are presented,
yielding information on minority carrier collection efficiency. The different
methods of parameter extraction are correlated and indicate recombination
levels some hundreds of meV above the valence band and below the conduction
band. Bias dependence of admittance spectroscopy gives indications on the
localisation of defect centres with one defect situated at the CdS
heterointerface and the other in the bulk of the depletion region. The dark
current analysis indicates that photogenerated minority carrier collection is
the limiting factor in these cells at the operating bias.

25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
19
The categories of this paper are: eess