Thin-film indium selenide prepared by reaction of selenium vapor with indium oxide

Journal Article · · Chemistry of Materials; (United States)

DOI:https://doi.org/10.1021/cm00024a053· OSTI ID:6772583

Weng, Shixing; Wynands, H; Cocivera, M ^[1]

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1. Univ. of Guelph, Ontario (Canada)

A new process involving two steps has been developed to prepare thin-film In[sub 2]Se[sub 3]. The first step is formation of indium oxide by spray pyrolysis of an aqueous solution of indium nitrate, and the second is reaction of this oxide with selenium vapor in nitrogen at atmospheric pressure to form In[sub 2]Se[sub 3]. Shorter exposure time was needed for complete conversion as the temperature was increased from 400 to 500[degree]C. Auger depth profiling of the composition of a partially converted film indicated that the conversion process appears to involve three steps: (a) reaction beteween selenium vapor and the oxide at the surface; (b) subsequent diffusion of selenium into the film until much of the oxide was converted to InSe; (c) further reaction involving selenium vapor and InSe to form In[sub 2]Se[sub 3]. It was possible to convert In[sub 2]Se[sub 3] into InSe by reacting it with indium vapor, and it was also possible to incorporate cadmium. p-type In[sub 2]Se[sub 3] and n-type InSe were prepared by this relatively inexpensive process. Resistance and Hall effect measurements gave a variety of resistivity and carrier density values, depending on the preparation conditions. X-ray diffraction indicated that the In[sub 2]Se[sub 3] film may consist of several crystalline phases, and optical absorption spectra indicated a direct bandgap of 1.84 eV. A direct bandgap of 3.64 eV was found for In[sub 2]O[sub 3], which was n-type and had a very low resistivity and high electron density. 35 refs., 5 figs., 2 tabs.

• OSTI ID: 6772583
• Journal Information: Chemistry of Materials; (United States), Vol. 4:6; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
INDIUM OXIDES
CHEMICAL REACTIONS
SPRAY COATING
INDIUM SELENIDES
CHEMICAL PREPARATION
SELENIUM
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
HALL EFFECT
PYROLYSIS
THIN FILMS
VAPORS
X-RAY DIFFRACTION
CHALCOGENIDES
COHERENT SCATTERING
DECOMPOSITION
DEPOSITION
DIFFRACTION
ELECTRICAL PROPERTIES
ELEMENTS
FILMS
FLUIDS
GASES
INDIUM COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
SELENIDES
SELENIUM COMPOUNDS
SEMIMETALS
SURFACE COATING
SYNTHESIS
THERMOCHEMICAL PROCESSES
360601* - Other Materials- Preparation & Manufacture
400201 - Chemical & Physicochemical Properties