We report on the achievement of a two dimensional electron gas in completely undoped In0.75Al0.25As/In0.75Ga0.25As metamorphic quantum wells. Using these structures we were able to reduce the carrier density, with respect to reported values in similar modulation – doped structures, to about 2 ÷ 3´ 1011 cm-2 with mobilities of up to 2.15´ 105 cm2 (V s)-1. We found experimentally that the electronic charge in the quantum well is likely due to deep – level donor states in the In0.75Al0.25As barrier band gap, whose energy lies within the In0.75Ga0.25As/In0.75Al0.25As conduction band discontinuity. This result is further confirmed through a Poisson – Schrödinger simulation of the two dimensional electron gas structure
F. Capotondi, G. Biasiol, I. Vobornik, F. Giazotto, L. Sorba, A. Cavallini, et al. (2004). Two dimensional electron gas formation in undoped In0.75Ga0.25As/In0.75Al0.25As quantum well. JOURNAL OF VACUUM SCIENCE & TECHNOLOGY. B, 22, 702-706 [10.1116/1.1688345].
Two dimensional electron gas formation in undoped In0.75Ga0.25As/In0.75Al0.25As quantum well
CAVALLINI, ANNA;FRABONI, BEATRICE
2004
Abstract
We report on the achievement of a two dimensional electron gas in completely undoped In0.75Al0.25As/In0.75Ga0.25As metamorphic quantum wells. Using these structures we were able to reduce the carrier density, with respect to reported values in similar modulation – doped structures, to about 2 ÷ 3´ 1011 cm-2 with mobilities of up to 2.15´ 105 cm2 (V s)-1. We found experimentally that the electronic charge in the quantum well is likely due to deep – level donor states in the In0.75Al0.25As barrier band gap, whose energy lies within the In0.75Ga0.25As/In0.75Al0.25As conduction band discontinuity. This result is further confirmed through a Poisson – Schrödinger simulation of the two dimensional electron gas structureI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
