Regensburg 2004 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Halbleiterphysik
HL 12: Poster I
HL 12.60: Poster
Montag, 8. März 2004, 16:30–19:00, Poster A
Resonant tunneling through self organized InAs Quantum dots — •T. Lüdtke1, F. Hohls1, R. J. Haug1, and K. Pierz2 — 1Universität Hannover, Germany, Solid State Physics, Department Nanostructures — 2Physikalisch-Technische Bundesanstalt Braunschweig
The aim of our work was to do electron transport measurements on resonant tunnelling devices containing only a few Quantum Dots (QD). The sample is an GaAs/AlAs/GaAs tunnelling diode containing one layer and in another one a double layer of self-organized InAs QD’s (1.5 - 2 ML) embedded in the AlAs barrier which lies about 1 µ m above the top. The diodes with dimension of a about 50µ m down to a few micrometers were defined by electron beam lithography (EBL). The interesting problem of contacting the small diodes to a bonding wire was solved with a polyimide (PI) layer surrounding the mesa. Then a hole above the diode is defined by EBL, and wet etching through the PI layer gave the opportunity to connect the diode to a top contact of about 80µ m. Temperature dependent characterization measurements down to 1.5 K as well as magnetic field variations were realized to study Coulomb Blockade, tunnel coupling in double QD’s and to calculate g-Factors.