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1/f Tunnel Current Noise through Si-bound Alkyl Monolayers

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 نشر من قبل Dominique Vuillaume
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report low frequency tunnel current noise characteristics of an organic monolayer tunnel junction. The measured devices, n-Si/alkyl chain (C18H37)/Al junctions, exhibit a clear 1/ f &#947; power spectrum noise with 1< &#947; <1.2. We observe a slight bias-dependent background of the normalized current noise power spectrum (SI/I^2). However, a local increase is also observed over a certain bias range, mainly if V > 0.4 V, with an amplitude varying from device to device. We attribute this effect to an energy-dependent trap-induced tunnel current. We find that the background noise, SI, scales with >. A model is proposed showing qualitative agreements with our experimental data.



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