Influence of background charges on Coulomb blockade in quantum dots

Single electron devices are being investigated widely for their use in logi c circuits and data storage devices. Here a point of concern is the sensiti vity of single electron transistors (SETs) to changing background charges, which may arise from freezing out or capture of single electrons in the vic inity of the devices in the substrate or the buried oxide of the silicon-on -insulator (SOI) material. SET structures have been fabricated on a SOI bas is and the effect of charges placed close to the quantum dot was investigat ed. This was performed in a low temperature scanning electron microscope (L TSEM), where a SET at liquid helium temperature was irradiated with electro ns. Characterization of the SETs in the LTSEM showed the appearance of 'ran dom telegraph noise'. (C) 2001 Elsevier Science B.V. All rights reserved.