Charge transport and trapping phenomena in off-stoichiometric silicon dioxide films

• DOI: 10.1063/1.331806
• Publication Date: 2003-02-14T18:32:07Z
• Authors: D. J. DiMaria; D. W. Dong; C. Falcony; T. N. Theis; J. R. Kirtley; J. C. Tsang; D. R. Young; F. L. Pesavento; S. D. Brorson
• Keywords: Polycrystalline silicon; Silicon dioxide; Stoichiometry

The electrical characteristics of off-stoichiometric silicon dioxide films have been investigated. oxide studied had an excess atomic (Si) content in the range 1%–6%. Raman spectroscopy and photoconductivity measurements indicate that Si is present as amorphous islands or small crystallites embedded (SiO2) forming a two-phase material. These differ structure from previously reported where dual dielectric layers stoichiometric SiO2 Si-rich with ≥13% were used. observed to produce electron injection contacting electrodes via layer into at lower average electric fields. This mechanism was believed be due localized field enhancement near SiO2–Si-rich interface caused by curvature tiny matrix. current versus voltage which will discussed here found highly nonohmic, showing increase conductivity increasing silcion At low fields (≲1 MV/cm), these very conductance leakage densities smaller than 10−11 A/cm2 room temperature. Furthermore, effect permanent charge trapping decrease content. It proposed transport across film controlled primarily tunneling between reversible space region ≲150 Å extent injecting contact, limiting measured external circuit. also associated this conduction and/or possibility trapped electrons phase islands. With incorporation oxides electrically-alterable read-only-memory devices, extended write/erase cycling (by least four orders magnitude) beyond normally for equivalent devices using demonstrated reduction its on