CdTe thin films: Spray deposition using a nanoparticle ink precursor

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:417696

Schulz, D L; Pehnt, M; Curtis, C J; Ginley, D S ^[1]

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1. National Renewable Energy Lab., Golden, CO (United States)

CdTe thin film growth using nanoparticle precursors and spray deposition has been investigated. Employing a metathesis approach, cadmium iodide was reacted with sodium telluride in methanol solvent resulting in the formation of soluble NaI and insoluble CdTe nanoparticles. After appropriate chemical workup, methanol-capped CdTe colloids were isolated. CdTe colloids prepared by this method exhibit a dependence of the nanoparticle diameter upon reaction temperature as determined by transmission electron microscopy (TEM) and UV-Visible spectroscopy (UV-Vis). CdTe thin film formation was achieved by spray depositing the nanoparticle colloids (25--75 {angstrom} diameter) onto substrates at elevated temperatures (T = 280--440 C) with no further thermal treatment. These films were characterized by XRD, x-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Cubic CdTe phase formation was observed by XRD with a contaminant oxide phase also detected. XPS analysis showed that CdTe films produced by this one-step method contained no Na or C, but substantial O. AFM gave CdTe grain sizes of {approximately}0.1--0.3 {micro}m for films sprayed at 400 C. A layer-by-layer film growth mechanism proposed for the one-step spray deposition of nanoparticle precursors will be discussed.

• OSTI ID: 417696
• Report Number(s): CONF-960401--; ISBN 1-55899-329-0
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
AIR
CADMIUM IODIDES
CADMIUM TELLURIDE SOLAR CELLS
CADMIUM TELLURIDES
CHEMICAL COMPOSITION
GRAIN SIZE
METHANOL
MICROSTRUCTURE
MORPHOLOGY
OXIDATION
PARTICLE SIZE
PHOTOELECTRON SPECTROSCOPY
SEMICONDUCTOR MATERIALS
SODIUM TELLURIDES
SPRAY COATING
SYNTHESIS
TEMPERATURE DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA
X-RAY DIFFRACTION