Publication Type |
Journal Article |
School or College |
College of Engineering |
Department |
Materials Science & Engineering |
Creator |
Scarpulla, Michael |
Other Author |
Yi, Wei; Narayanamurti, Venkatesh; Lu, Hong; Gossard, Arthur C. |
Title |
Probing semiconductor band structures and heterojunction interface properties with ballistic carrier emission: GaAs/AlxGa1-xAs as a model system |
Date |
2010-06 |
Description |
Utilizing three-terminal tunnel emission of ballistic electrons and holes in a planar tunnel transistor with a Mott-barrier collector, we have developed a method to self-consistently determine the energy gap of a semiconductor and band discontinuities at a semiconductor heterojunction without using a priori material parameters. Measurements are performed on lattice-matched GaAs/AlxGa1−xAs (100) single-barrier double heterostructures with AlxGa1−xAs as the model ternary IIIV compounds. Electronic band gaps of the AlGaAs alloys and band offsets at the GaAs/AlGaAs (100) interfaces are measured with a resolution of several meV at 4.2 K. The direct-gap I band offset ratio for the GaAs/AlGaAs (100) interface is found to be 59:41 (±3%). Reexamination of our previous experiment [W. Yi et al., Appl. Phys. Lett. 95, 112102 (2009)] revealed that, in the indirect-gap regime, ballistic electrons from direct tunnel emissions probe the X valley in the conduction band, while those from Auger-like scattering processes in the metal base film probe the higher-lying L valley. Such selective electron collection may be explained by their different momentum distributions and parallel momentum conservation at the quasiepitaxial Al/GaAs (100) interface.We argue that the present method is in principle applicable to arbitrary type-I semiconductor heterostructures. |
Type |
Text |
Publisher |
American Physical Society |
Journal Title |
Physical Review B |
Volume |
81 |
Issue |
23 |
First Page |
235325 |
Last Page |
235321 |
DOI |
10.1103/PhysRevB.81.235325 |
citatation_issn |
1098-0121 |
Language |
eng |
Bibliographic Citation |
Yi, W., Narayanamurti, V., Lu, H., Scarpulla, M., & Gossard, A. C. (2010). Probing semiconductor band structures and heterojunction interface properties with ballistic carrier emission: GaAs/AlxGa1-xAs as a model system. Physical Review B, 81, 235325-1-235325-13. |
Rights Management |
(c) American Physical Society http://dx.doi.org/DOI: 10.1103/PhysRevB.81.235325 |
Format Medium |
application/pdf |
Format Extent |
1,005,684 bytes |
Identifier |
ir-main,15539 |
ARK |
ark:/87278/s66h51zd |
Setname |
ir_uspace |
ID |
706288 |
Reference URL |
https://collections.lib.utah.edu/ark:/87278/s66h51zd |