Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Formation of ordered arrays of Ag nanowires and nanodots on Si(5 5 7)
  surface   The ordered arrays of Ag nanowires and nanodots have been grown in ultra-high
vacuum on the Si(5 5 7) surface containing regular steps of three bilayer
height. Formation of Ag nanostructures have been studied by scanning tunneling
microscopy, low energy electron diffraction and Auger electron spectroscopy at
room temperature. It was shown that a sample exposure in the vacuum before Ag
growth affects the shape of the forming Ag islands. This effect is caused by
oxygen adsorption on the silicon surface from the residual atmosphere in the
vacuum chamber. When Ag is deposited on the clean silicon surface the islands,
overlapping several (1 1 1) neighboring terraces, form. The arrays of silver
nanowires elongated along steps and silver nanodots, arranged in lines parallel
to the steps, can be formed on the Si(5 5 7) surface depending on the amount of
adsorbed oxygen.

25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci