Ultralarge area MOS tunnel devices for electron emission

Article

关键词: INTERFACE OXIDATION-KINETICS;    SUBSTRATE DOPING LEVELS;    PHYSICAL MODEL;    HOT-ELECTRONS;    SILICON;    FEMTOCHEMISTRY;    MICROSCOPY;    ROUGHNESS;    JUNCTIONS;    BREAKDOWN;   

DOI  :  10.1103/PhysRevB.76.155315

来源: SCIE

【 摘 要 】

A comparative analysis of metal-oxide-semiconductor (MOS) capacitors by capacitance-voltage (C-V) and current-voltage (I-V) characteristics has been employed to characterize the thickness variations of the oxide on different length scales. Ultralarge area (1 cm(2)) ultrathin (similar to 5 nm oxide) MOS capacitors have been fabricated to investigate their functionality and the variations in oxide thickness, with the use as future electron emission devices as the goal. I-V characteristics show very low leakage current and excellent agreement to the Fowler-Nordheim expression for the current density. Oxide thicknesses have been extracted by fitting a model based on Fermi-Dirac statistics to the C-V characteristics. By plotting I-V characteristics in a Fowler plot, a measure of the thickness of the oxide can be extracted from the tunnel current. These apparent thicknesses show a high degree of correlation to thicknesses extracted from C-V characteristics on the same MOS capacitors, but are systematically lower in value. This offset between the thicknesses obtained by C-V characteristics and I-V characteristics is explained by an inherent variation of the oxide thickness. Comparison of MOS capacitors with different oxide areas ranging from 1 cm(2) to 10 mu m(2), using the slope from Fowler-Nordheim plots of the I-V characteristics as a measure of the oxide thickness, points toward two length scales of oxide thickness variations being similar to 1 cm and similar to 10 mu m, respectively.

【 授权许可】

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