Title :
Observation of novel conductance structure in GaAs/GaxAl 1-xAs resonant tunneling heterostructures
Author :
Deshpande, M.R. ; Dekker, N.H. ; Sleight, J.W. ; Huber, J.L. ; Hornbeck, E.S. ; Reed, M.A. ; Matyi, R.J. ; Kao, Y.C. ; Fernando, C.J.L. ; Frensley, W.R.
Author_Institution :
Yale Univ., New Haven, CT, USA
Abstract :
A novel pre-resonant conductance structure is observed in single and double well GaAs/GaxAl1-xAs resonant tunneling heterostructures. This structure is attributed to single electron tunneling through donor bound states in the quantum well as they cross the Fermi level. Peaks in conductance are observed in devices as large as (64μ)2. We observe for the first time donor binding energies in quantum wells as large as 35 meV, which is probably due to the formation of a donor complex. An impressive impurity tunneling conductance structure is observed in double quantum well structures with conductance peak heights varying over 3 orders of magnitude. Conductance peaks are observed before and after the main resonant current peak which are attributed to tunneling of electrons through impurities in one quantum well and the quantum state in the other well
Keywords :
Fermi level; binding energy; electric admittance; gallium arsenide; resonant tunnelling devices; semiconductor quantum wells; semiconductor superlattices; 35 meV; 64 mum; Fermi level; GaAs-GaAlAs; GaAs/GaxAl1-xAs; conductance peak heights; donor binding energies; donor bound states; donor complex; double well; impurity tunneling conductance structure; novel conductance structure; pre-resonant conductance structure; quantum state; quantum well; resonant current peak; resonant tunneling heterostructures; single electron tunneling; single well; Analog-digital conversion; Electrons; Gallium arsenide; Impurities; Instruments; Oscillators; Resonance; Resonant tunneling devices; Switching converters; Voltage;
Conference_Titel :
High Speed Semiconductor Devices and Circuits, 1993. Proceedings., IEEE/Cornell Conference on Advanced Concepts in
Conference_Location :
Ithaca, NY
Print_ISBN :
0-7803-0894-8
DOI :
10.1109/CORNEL.1993.303084
