Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface preparation and patterning by nano imprint lithography for the
  selective area growth of GaAs nanowires on Si(111)   The selective area growth of Ga-assisted GaAs nanowires (NWs) with a high
vertical yield on Si(111) substrates is still challenging. Here, we explore
different surface preparations and their impact on NW growth by molecular beam
epitaxy. We show that boiling the substrate in ultrapure water leads to a
significant improvement in the vertical yield of NWs (realizing 80%) grown on
substrates patterned by electron-beam lithography (EBL). Tentatively, we
attribute this improvement to a reduction in atomic roughness of the substrate
in the mask opening. On this basis, we transfer our growth results to
substrates processed by a technique that enables the efficient patterning of
large arrays, nano imprint lithography (NIL). In order to obtain hole sizes
below 50 nm, we combine the conventional NIL process with an indirect pattern
transfer (NIL-IPT) technique. Thereby, we achieve smaller hole sizes than
previously reported for conventional NIL and growth results that are comparable
to those achieved on EBL patterned substrates.

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The categories of this paper are: gr-qc
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
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The categories of this paper are: physics
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
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The categories of this paper are: cs