Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transient terahertz photoconductivity measurements of minority-carrier
  lifetime in tin sulfide thin films: Advanced metrology for an early-stage
  photovoltaic material   Materials research with a focus on enhancing the minority-carrier lifetime of
the light-absorbing semiconductor is key to advancing solar energy technology
for both early-stage and mature material platforms alike. Tin sulfide (SnS) is
an absorber material with several clear advantages for manufacturing and
deployment, but the record power conversion efficiency remains below 5%. We
report measurements of bulk and interface minority-carrier recombination rates
in SnS thin films using optical-pump, terahertz (THz)-probe transient
photoconductivity (TPC) measurements. Post-growth thermal annealing in H_2S gas
increases the minority-carrier lifetime, and oxidation of the surface reduces
the surface recombination velocity. However, the minority-carrier lifetime
remains below 100 ps for all tested combinations of growth technique and
post-growth processing. Significant improvement in SnS solar cell performance
will hinge on finding and mitigating as-yet-unknown recombination-active
defects. We describe in detail our methodology for TPC experiments, and we
share our data analysis routines as freely-available software.

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The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph