Controlling surfaces and interfaces of semiconductors using organic molecules

Abstract Control over semiconductor surface energetics can be achieved using different chemisorbed organic molecules with diverse electronic properties. We find evidence of such control over CdTe upon adsorption of dicarboxylic acid derivatives with different substituted phenyl rings. FT-IR measurements show that the dicarboxylic acid derivatives bind as carboxylates to form approximately one monolayer. Such chemisorption modifies both the band bending and the electron affinity (up to 500 and 700 mV, respectively), as measured by contact potential difference WPM Changes in band bending result from a coupling between molecular orbitals and surface states close to the valence band and depend on the withdrawing character of the phenyl substituent. A model is presented to interpret and explain the data.

[1]  Joseph P. Lorenzo,et al.  Indium phosphide passivation using thin layers of cadmium sulfide , 1995 .

[2]  J. Libman,et al.  Simultaneous Control of Surface Potential and Wetting of Solids with Chemisorbed Multifunctional Ligands , 1997 .

[3]  D. Lin-Vien.  The Handbook of Infrared and Raman Characteristic Frequencies of Organic Molecules , 1991 .

[4]  M. Matsumura,et al.  Effect of EDTA on the photocatalytic activities and flatband potentials of cadmium sulfide and cadmium selenide , 1990 .

[5]  W. Mönch.  Semiconductor Surfaces and Interfaces , 1994 .

[6]  J. Libman,et al.  Controlling electronic properties of CdTe by adsorption of dicarboxylic acid derivatives: Relating molecular parameters to band bending and electron affinity changes , 1997 .

[7]  D. Cahen,et al.  Defect chemical explanation for the effect of air anneal on CdS/CuInSe2 solar cell performance , 1989 .

[8]  Eli Yablonovitch,et al.  Nearly ideal electronic properties of sulfide coated GaAs surfaces , 1987 .

[9]  M. Natan,et al.  Interaction of diethyldithiocarbamate with n-type cadmium sulfide and cadmium selenide: efficient photoelectrochemical oxidation to the disulfide and flat-band potential of the semiconductor as a function of adsorbate concentration , 1986 .

[10]  C. Murphy,et al.  Photoluminescence-Based Correlation of Semiconductor Electric Field Thickness with Adsorbate Hammett Substituent Constants. Adsorption of Aniline Derivatives onto Cadmium Selenide , 1990 .

[11]  K. Nakamoto.  Infrared and Raman Spectra of Inorganic and Coordination Compounds , 1978 .

[12]  Bruce A. Parkinson,et al.  Effects of Cations on the Performance of the Photoanode in the n-GaAs |K2Se-K2Se2-KOH|C Semiconductor Liquid Junction Solar Cell , 1979 .

[13]  David Cahen,et al.  POLAR LIGAND ADSORPTION CONTROLS SEMICONDUCTOR SURFACE POTENTIALS , 1994 .

[14]  A. Ellis,et al.  Photoluminescence as a probe of the adsorption of gaseous boranes onto the surface of cadmium selenide crystals , 1993 .

[15]  R. C. Weast.  CRC Handbook of Chemistry and Physics , 1973 .

[16]  Jimmy C. Yu,et al.  Semiconductor―olefin adducts. Photoluminescent properties of cadmium sulfide and cadmium selenide in the presence of butenes , 1989 .

[17]  S. Wiberley,et al.  Introduction to infrared and Raman spectroscopy , 1965 .

[18]  N. Lewis,et al.  Chemical studies of the passivation of GaAs surface recombination using sulfides and thiols , 1991 .

[19]  C. Stahle,et al.  Etching on polar (111) surfaces of CdTe crystals studied with Auger electron spectroscopy , 1987 .

[20]  R. H. Williams,et al.  Effects of surface treatments on Schottky barrier formation at metal/n‐type CdTe contacts , 1989 .

[21]  A. Shanzer,et al.  CONTROLLING THE WORK FUNCTION OF CDSE BY CHEMISORPTION OF BENZOIC ACID DERIVATIVES AND CHEMICAL ETCHING , 1995 .