Electrical Properties of Nanocrystalline n-SnO2 to Single Crystal p-Si Interfaces under Gas Adsorption Conditions
Autor: | Alexander Gaskov, Ludmila I. Ryabova, Marina Rumyantseva, Roman B. Vasiliev, B. A. Akimov |
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Rok vydání: | 2001 |
Předmět: | |
Zdroj: | physica status solidi (a). 188:1093-1104 |
ISSN: | 1521-396X 0031-8965 |
DOI: | 10.1002/1521-396x(200112)188:3<1093::aid-pssa1093>3.0.co;2-x |
Popis: | We present a study of heterostructures based on thin n-SnO 2 layers prepared by means of an aerosol pyrolysis on a single crystalline p-Si substrate. SnO 2 films are composed of 6-8 nm grains segregated into agglomerates of about 0.1 μm providing a porous structure of the film. Current-voltage (I-V) characteristics are taken in the temperature interval 180-300 K. Capacitance-voltage (C-V) curves are obtained at frequencies of the reference signal varied within 0.5-20 kHz at 300 K. Electrical properties of the structures were examined in air and in gas mixtures N 2 + 0.1% NO 2 and N 2 + 1% C 2 H 5 OH. A pronounced non-linearity of the I-V curves is explained in terms of the Schottky equation with high ideality factors β 7 - 11. The gas sensitivity S depends on the kind of adsorbed gas molecule due to the Schottky barrier variation together with the interface states density change. The SnO 2 doping with Ni induces an increase of S by an order of magnitude. |
Databáze: | OpenAIRE |
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