Electrochemical atomic layer epitaxy studies

Cachet H, Cortes R, Froment M, Mamin G (1999) Epitaxial growth of electrodeposited cadmium selenide on (111) gallium arsenide. Philos Mag Lett 79/10 837-840 Muthuvel M, Stickney JL (2006) CdTe Electrodeposition on InP(lOO) via Electrochemical Atomic Layer Epitaxy (EC-ALE) Studies Using UHV-EC. Langmuir 22 5504-5508 Streltsov EA, Osipovich NP, Ivashkevich LS, Lyakhov AS (1999) Effect of Cd(ll) on electrodeposition of textured PbSe. Electrochim Acta 44 2645-2652 Beaunier L, Cachet H, Cortes R, Froment M (2000) Electrodeposition of PbSe epitaxial films on (111) InP. Electrochem Commun 2 508-510... 

Gregory BW, Suggs DW, Stickney JL (1991) Conditions for the deposition of CdTe by electrochemical atomic layer epitaxy. J Electrochem Soc 138 1279-1284 Suggs DW, Stickney JL (1991) Characterization of atomic layers of tellurium electrodeposited on the low-index planes of gold. J Phys Chem 95 10056-64 Suggs DW, Stickney JL (1993) Studies of the structures formed by the alternated electrodeposition of atomic layers of Cd and Te on the low-index planes of Au. 1. LEED and Auger studies. Surf Sci 290 362-374... 

Varazo K, Lay MD, Sorenson TA, Stickney JL (2002) Formation of the first monolayers of CdTe on Au(l 11) by electrochemical atomic layer epitaxy (EC-ALE) studied by LEED, Auger, XPS, and in-situ STM. J Electroanal Chem 522 104-114... 

Colletti LP, Teklay D, Stickney JL (1994) Thin-layer electrochemical studies of the oxidative underpotential deposition of sulfur and its application to the electrochemical atomic layer epitaxy deposition of CdS. J Electroanal Chem 369 145-152... 

Colleti LP, Thomas S, WUmer EM, Stickney JL (1997) Thin layer electrochemical studies of ZnS, ZnSe, and ZnTe formation by Electrochemical Atomic Layer Epitaxy (ECALE). Mater Res Soc Symp Proc 451 235. 

Venkatasamy V, Mathe MK, Cox SM, Happek U, Stickney JL (2006) Optimization studies of HgSe thin film deposition by electrochemical atomic layer epitaxy (EC-ALE). Electrochim Acta 51 4347-4351... 

Cecconi, T. Atrei, A. Bardi, U. Forni, F. Innocenti, M. Loglio F. Foresti M. Rovida G. 2001. X-ray photoelectron diffraction (XPD) study of the atomic structure of the ultrathin CdS phase deposited on Ag(lll) by electrochemical atomic layer epitaxy (ECALE). J. Electron Spectrosc. Relat. Phenom. 114-116 563-568. 

Villegas, I. Stickney, J. L. 1992. Preliminary studies of gallium arsenide deposition on gold (100), (110), and (111) surfaces by electrochemical atomic layer epitaxy. J. Electrochem. Soc. 139 686-94. 

This paper describes ongoing studies of the electrodeposition thin films of the compound semiconductors CdTe and InAs, using the method of electrochemical atomic layer epitaxy (ALE). Surface limited electrochemical reactions are used to form the individual atomic layers of the component elements. An automated electrochemical flow deposition system is used to form the atomic layers in a cycle. Studies of the conditions needed to optimize the deposition processes are underway. The deposits were characterized using X-ray diffraction, scanning probe microscopy, electron probe microanalysis and optical/infrared absorption spectroscopy. 

The use of electrochemical atomic layer epitaxy for the electrosynthesis of high quality thin films of thermoelectric materials is studied. Specifically, the use of sequential underpotential deposition (upd) cycles of Sb and Co for the production of CoSb phases on Au substrates is investigated. Stable atomic layers of Sb can be formed on Au, and were imaged for the first time by STM. These layers consist of randomly distributed islands of Sb with a mean diameter of 5.5 nm and a mean height of 0.35 nm. Co upd layers appear to form in situ on Au, but do not survive transfer to the Sb deposition solution. In contrast, stable upd layers of Co can be produced on the Sb/Au surface. In addition, there is a 180 mV positive shift of the Co upd formal potential to more positive values, suggestive of the formation of a stable CoSb phase. 

Electrochemical atomic layer epitaxy (EC-ALE) is the combination of underpotential deposition (UPD) and ALE. UPD is the formation of an atomic layer of one element on a second element at a potential under, or prior to, that needed to deposit the element on itself [5, 6]. The shift in potential results from the free energy of the surface compound formation. Early UPD studies were carried out mostly on polycrystalline electrode surfaces [7], This was due, at least in part, to the difficulty of preparing and maintaining single-crystal electrodes under well-defined conditions of surface structure and cleanliness [8]. The definition of epitaxy is variable but focuses on the formation of single crystal films on single crystal substrates. This is different from other thin film deposition methods where polyciystalline or amorphous film deposits are formed even on single crystal substrates. Homoepitaxy is the formation of a compound on itself. Heteroepitaxy is the formation of a compound on a different compound or element and is much... 

Huang B et al (1995) Preliminary studies of the use of an automated flow-cell electrodeposition system for the formation of CdTe thin films by electrochemical atomic layer epitaxy. J Electrochem Soc 142 3007-3016... 

Atomic layer epitaxy, 117 Atomic level studies of CdTe(lOO), electrochemical digital etching, 115-123 Auger electron spectrometers, 106 Auger electron spectroscopy bisulfate anion adsorption on Au(l 11), Pt(l 11), and Rh(l 11) surfaces, 126-138 to monitor composition of acidified water surfaces, 106-114 underpotential deposition of lead on Cu(lOO) and Cu(lll), 142-154 use for bisulfate anion adsorption, 127... 

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