Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Selective etching of PDMS: etching as positive resist   Although, poly(dimethylsiloxane) (PDMS) is a widely used material in numerous
applications, such as micro- or nanofabrication, the method of its selective
etching has not been known up to now. In this work authors present two methods
of etching the pure, additive-free and cured PDMS as a positive resist
material.
  To achieve the chemical modification of the polymer necessary for selective
etching, energetic ions were used. We created 7 um and 45 um thick PDMS layers
and patterned them by a focused proton microbeam with various, relatively large
fluences. In this paper authors demonstrate that 30 wt% Potassium Hydroxide
(KOH) or 30 wt% sodium hydroxide (NaOH) at 70 oC temperature etch proton
irradiated PDMS selectively, and remove the chemically sufficiently modified
areas. In case of KOH development, the maximum etching rate was approximately
3.5 um/minute and it occurs at about 7.5*10^15 ion*cm-2. In case of NaOH
etching the maximum etching rate is slightly lower, 1.75 um/minute and can be
found at the slightly higher fluence of 8.75*10^15 ion*cm-2.
  These results are of high importance since up to this time it has not been
known how to develop the additive-free, cross-linked poly(dimethylsiloxane) in
lithography as a positive tone resist material.

28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th