| 11. |
- Borg, Mattias, et al.
(författare)
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GaAs/GaSb nanowire heterostructures grown by MOVPE
- 2008
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Ingår i: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248. ; 310:18, s. 4115-4121
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Tidskriftsartikel (refereegranskat)abstract
- We report Au-assisted growth of GaAs/GaSb nanowire heterostructures on GaAs(1 1 1)B-substrates by metal-organic vapor phase epitaxy. The growth is studied at various precursor molar fractions and temperatures, in order to optimize the growth conditions for the GaSb nanowire segment. In contrast to most other III-V nanowire systems, the GaSb nanowire growth is Group V-limited under most conditions. We found that depending on the TMSb molar fraction, the seed particle is either supersaturated AuGa or AuGa2 during GaSb growth. The high Ga content in the particle gives a characteristic diameter increase between the GaAs and GaSb segment. From TEM and XEDS measurements we conclude that the GaSb nanowire growth occurs along either the AuGa-GaSb or AuGa2-GaSb pseudo-binaries of the Au-Ga-Sb ternary phase diagram. Finally, the GaSb nanowires exhibit untapered radial growth on the {1 (1) over bar 0} side facets. (C) 2008 Elsevier B.V. All rights reserved.
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| 12. |
- Borgström, Magnus, et al.
(författare)
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Site control of InAs quantum dots on a patterned InP surface: As/P exchange reactions
- 2003
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Ingår i: Journal of Crystal Growth. - 0022-0248. ; 248, s. 310-316
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Tidskriftsartikel (refereegranskat)abstract
- In this paper. we present the effect of annealing temperature and annealing time on InAs site-controlled quantum dot growth. Individual InAs quantum dots formed by self-assembling have been positioned into holes, created by partial overgrowth of electron beam induced nano-carbon deposits by metal organic vapor phase epitaxy. As/P exchange reactions produce material sufficient for selective dot nucleation in the holes. Results. showing that As/P exchange reactions occur even when capping the dots with InP are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
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| 13. |
- Borgström, Magnus, et al.
(författare)
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Site-control of InAs quantum dots on a patterned InP surface: As/P exchange reactions
- 2002
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Ingår i: 7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science.
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Konferensbidrag (refereegranskat)abstract
- We present the effect of annealing temperature and annealing time on InAs/InP site-controlled quantum dot growth. Electron beam pre-patterning forms carbon nano-deposits at the InP surface, which then can be used as growth masks to form nano-holes at the surface. By only annealing of the patterned InP surface under an arsine ambient, As/P exchange reactions produce material sufficient for selective dot nucleation in the holes at the surface
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| 14. |
- Bryllert, Tomas, et al.
(författare)
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Designed emitter states in resonant tunneling through quantum dots
- 2002
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 80:15, s. 2681-2683
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Tidskriftsartikel (refereegranskat)abstract
- Resonant tunneling through a single layer of self-assembled quantum dots (QDs) is compared to tunneling through two layers of vertically aligned (stacked) dots. The difference can be viewed as going from a two-dimensional emitter to a zero-dimensional emitter. The temperature dependence of current peaks originating in tunneling through individual QDs and individual stacks is used to clarify this point. In addition, we show that the statistical size distribution of self-assembled quantum dots causing the inhomogeneous broadening in luminescence experiments can be analyzed in a resonant tunneling experiment. (C) 2002 American Institute of Physics.
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| 15. |
- Bryllert, Tomas, et al.
(författare)
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Resonant tunneling through coupled self-assembled quantum dots and the influence of inhomogeneous broadening
- 2002
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Ingår i: 7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science.
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Konferensbidrag (refereegranskat)abstract
- Resonant tunneling through a single layer of self-assembled quantum dots (QDs) as well as tunneling through two layers of vertically aligned (stacked) dots is investigated. The difference between single and double layers of QDs can be viewed as going from a two-dimensional emitter to a zero-dimensional emitter. By fabricating small-area devices we are able to probe single stacks of quantum dots, revealing details of the coupling between the stacked dots. Very sharp resonances, with peak-to-valley ratios of several hundred, have been measured in the current-voltage characteristics. We also show that the statistical size distribution of self-assembled quantum dots causing the inhomogeneous broadening in luminescence experiments can be analysed in a resonant tunneling experiment
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| 16. |
- Bryllert, Tomas, et al.
(författare)
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Transport through an isolated artificial molecule formed from stacked self-assembled quantum dots
- 2003
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 82:16, s. 2655-2657
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Tidskriftsartikel (refereegranskat)abstract
- We investigate resonant tunneling through two coupled self-assembled quantum dots. The strong confinement and the high crystalline quality provided by the self-assembled dots, in combination with the tunneling coupling between the dots, create a system that may be thought of as an artificial molecule. We are able to isolate one single artificial molecule and detailed investigations of the electrical properties are performed. Peak-to-valley ratios above 1000 and full width half maximum of a few millivolts are measured at 4 K. By changing the temperature we also observe Coulomb blockade effects in a different way. (C) 2003 American Institute of Physics.
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| 17. |
- Bryllert, Tomas, et al.
(författare)
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Vertical high-mobility wrap-gated InAs nanowire transistor
- 2006
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Ingår i: IEEE Electron Device Letters. - 0741-3106 .- 1558-0563. ; 27:5, s. 323-325
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Tidskriftsartikel (refereegranskat)abstract
- In this letter, the authors demonstrate a vertical wrap-gated field-effect transistor based on InAs nanowires [Proc. DRC, 2005, p. 157]. The nanowires have a diameter of 80 nm and are grown using selective epitaxy; a matrix of typically 10 x 10 vertically standing wires is used as channel in the transistor. The authors measure current saturation at V-ds = 0.15 V (V-g = 0 V), and a high mobility, compared to the previous nanowire transistors, is deduced.
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| 18. |
- Bryllert, Tomas, et al.
(författare)
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Vertical high mobility wrap-gated InAs nanowire transistor
- 2005
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Ingår i: 63rd Device Research Conference Digest, 2005. DRC '05. - 0780390407 ; 1
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Konferensbidrag (refereegranskat)abstract
- We demonstrate a wrap-gated field effect transistor based on a matrix of vertically standing InAs nanowires (Jensen, et. al., 2004). A lower limit of the mobility, derived from the transconductance, is on the order of 3000 cm2/Vs. The narrow ~100 nm channels show excellent current saturation and a threshold of Vg = -0.15 V. The sub-threshold characteristics show a close to ideal slope of 62mV/decade over two orders of magnitude
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| 19. |
- Bryllert, Tomas, et al.
(författare)
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Vertical wrap-gated nanowire transistors
- 2006
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Ingår i: Nanotechnology. - 0957-4484. ; 17:11, s. 227-230
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Tidskriftsartikel (refereegranskat)abstract
- We present a process for fabricating a field-effect transistor based on vertically standing InAs nanowires and demonstrate initial device characteristics. The wires are grown by chemical beam epitaxy at lithographically defined locations. Wrap gates are formed around the base of the wires through a number of deposition and etch steps. The fabrication is based on standard III - V processing and includes no random elements or single nanowire manipulation.
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| 20. |
- Carlberg, Patrick, et al.
(författare)
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Nanoimprint - a tool for realizing nano-bio research
- 2004
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Ingår i: 2004 4th IEEE Conference on Nanotechnology. - 0780385365 ; , s. 199-200
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Konferensbidrag (refereegranskat)abstract
- In this paper, we present a status report on how implementation of nanoimprint lithography has advanced our research. Contact guidance nerve growth experiments have so far primarily been done on micrometer-structured surfaces. We have made a stamp with 17 areas of different, submicron, line width and spacing covering a total 2.6 mm
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