Premium
Investigation of Carrier Tunneling in Short‐Period a‐Si/SiO 2 Quantum Structures with a Scanning Tunneling Microscope
Author(s) -
Golonzka O. V.,
Smolyaninov I. I.,
Vinogradov E. A.,
Zayats A. V.,
Pudonin F. A.
Publication year - 1994
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2221810112
Subject(s) - quantum tunnelling , scanning tunneling microscope , condensed matter physics , scanning tunneling spectroscopy , excited state , spin polarized scanning tunneling microscopy , quantum well , electron , materials science , amorphous solid , biasing , atomic physics , voltage , chemistry , physics , optics , quantum mechanics , organic chemistry , laser
Abstract Current‐voltage ( I‐V ) characteristics of short‐period (≦2.0 nm) amorphous Si/SiO 2 quantum structures (QWs) are investigated with a scanning tunneling microscope (STM). The tunneling current regime has been realized so that the applied bias is dropped mainly across the tip‐sample contact and the nondistorted energy structure of the QW conduction band is probed by tunneling electrons. Such measurements give the possibility to obtain energy positions of QW subbands without additional assumptions about the voltage drop across the layers. The I‐V curves observed are described taking into account sequential resonant tunneling. In the flow current regime the negative differential resistance caused by alignment of ground and first excited electron states is observed even at room temperature due to the high barrier in a‐Si/SiO 2 QWs.