Year: 2011
Type: article
Abstract: The electro-deposition of compound semiconductors has been attracting more attention because of its ability to rapidly deposit nanostructured materials and thin films with controlled morphology, dimensions, and crystallinity in a costeffective manner (1). In particular, low band-gap $A_2B_3$ -type chalcogenides, such as $Sb_2Te_3$ and $Bi_2Te_3$ , have been extensively studied because of their potential applications in thermoelectric power generator and cooler and phase change memory. Thermoelectric $Sb_xTe_y$ films were potentiostatically electrodeposited in aqueous nitric acid electrolyte solutions containing different ratios of $TeO_2$ to $Sb_2O_3$ . The stoichiometric $Sb_xTe_y$ films were obtained at an applied voltage of -0.15V vs. SCE using a solution consisting of 2.4 mM $TeO_2$ , 0.8 mM $Sb_2O_3$ , 33 mM tartaric acid, and 1M $HNO_3$ . The stoichiometric $Sb_xTe_y$ films had the rhombohedral structure with a preferred orientation along the [015] direction. The films featured hole concentration and mobility of $5.8{\times}10^{18}/cm^3$ and $54.8\;cm^2/V{\cdot}s$ , respectively. More negative applied potential yielded more Sb content in the deposited $Sb_xTe_y$ films. In addition, the hole concentration and mobility decreased with more negative deposition potential and finally showed insulating property, possibly due to more defect formation. The Seebeck coefficient of as-deposited $Sb_2Te_3$ thin film deposited at -0.15V vs. SCE at room temperature was approximately 118 ${\mu}V/K$ at room temperature, which is similar to bulk counterparts.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2036253766