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Zinc oxide films prepared
by sol-gel spin coating
指導老師：林克默
學
生：吳仕賢
報告日期：2010.01.15
Y. Natsume, H. Sakata, Thin Solid Films 372 (2000) 30.
Department of Applied Chemistry, School of Engineering, Tokai University, 1117, Kitakaname, Hiratsuka,
Kanagawa, 259-1292, Japan.
大綱
 前言
 實驗流程
 結果與討論
 結論
前言
ZnO films are n-type wide-gap semiconductors with optical
transparency in the visible range.
 Zinc oxide films deposited by chemical spray pyrolysis had
resistivities (~10-3 Ωcm).
 Al-doped ZnO films formed by sol-gel dip coating gave
resistivities of (7-10) × 10-4 Ωcm.
 No reports are found on zinc oxide films prepared by sol-gel
spin-coating that can be made with a simple coating apparatus.

實驗流程
結果與討論
The (002) peak intensity increased with an
increase in the annealing temperature.
However, the full width at half-max-ima
(FWHM) of the (002) peaks was hardly
changed with increasing film annealing
temperature.
Hence, the multiple-coating or piling up of
each ZnO film was considered not to
disturb the overall growth of the films with
c-axis orientation.
We confirmed that this shoulder peak
was thought to be due to metallic zinc
present, as interstitial atoms, in the
lattice of ZnO crystallites in the film,
rather than reduced Zn by Ar+ sputteretching, because the shoulder peak
existed from the outermost surface.
However, the resistivity increased mildly
because the decrease of the carrier
concentration might be controlled because
of decreasing defects that produce donor
levels, as a result, decomposition and
oxidation of the precursor films became
more active, and a better stoichiometry of
the ZnO films was formed above 525℃,
rather than the change of the mobility with
the annealing temperature.
where Ea1 is the activation energy for
band conduction as defined in Eq. 3.,
Ea2 , the activation energy for nearest
neighbor hopping conduction, k, the
Boltzmann constant and σ1 and σ2, the
pre-exponential factors,espectively.
結論
The160-230nm thick films formed on Pyrex glass substrate were
polycrystalline with c-axis orientation.
 A minimum d.c. resistivity of 28.2 Ωcm was obtained by a 10cycle spin-coating of zinc acetate film followed by annealing in
air at a temperature of 525℃.
 Grain boundary scattering was caused by thermionic emission of
electrons over grain boundaries.
 The optical band gap energy was obtained to be Eopt =3.2-3.21 ev
for the films.
