TITLE:
Preparation of CuYO2 Thin Films by Sol-Gel Method Using Copper Acetate and Yttrium Acetate as Metal Sources
AUTHORS:
Takashi Ehara
KEYWORDS:
CuYO2, Delafossite, Sol-Gel, Thin Films, Photoluminescence
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.4 No.1,
January
11,
2016
ABSTRACT:
Delafossite structured p-type wide bandgap
semiconductor, CuYO2 thin films were prepared on SiO2 substrate by sol-gel
method using copper (II) acetate and yttrium (III) acetate as source materials.
The films preparation process was studied by varying annealing temperature
after the preparation of gel films by spin coating, followed by thermal annealing
at higher temperature. In the present work, one step annealing directly from
Cu-Y-gel under nitrogen flow was used. X-ray diffraction (XRD) revealed that
the film annealed at 800。C is significantly c-axis oriented, shows only (002)
and (004) peaks at 15.6。 and 31.5。, respectively. The optical bandgap of 3.7 - 3.8
eV is estimated by (αhν)2 plot which is higher than previous works. In
addition, the films with highly c-axis orientation showed photoluminescence
(PL) at room temperature with very broad peak at 2.3 eV. The films annealed at
different temperature showed different structural properties.