| Project/Area Number |
09650393
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
電子デバイス・機器工学
|
|---|
| Research Institution | Osaka Institute of Technology |
|---|
Principal Investigator |
SASA Shigehiko Electrical Engineering, Osaka Institute of Technology, Associate Professor, 工学部, 助教授 (50278561)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
INOUE Masataka Electrical Engineering, Osaka Institute of Technology, Professor, 工学部, 教授 (20029325)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Project Status |
Completed (Fiscal Year 1998)
|
| Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1998: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1997: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
|---|
| Keywords | InAs / AlGaSb / quantum effect devices / atomic force microscope / AFM oxidation / single electron devices / type-II heterostructure / 原子間力顕微鏡 / 共鳴トンネル / バンド間トンネル |
|---|
| Research Abstract |
For the realization of quantum devices that operate at room temperature, we explored the molecular beam epitaxial growth conditions, nanofabrication processes, and their electronic properties of InAs/AlGaSb heterostructures. We found that anodic oxidation made by atomic force microscope (AFM) is a promising fabrication method with the typical fabrication size less than 100 nm and developed various process techniques using AFM oxidation for the fabrication of various types of devices.
In order to demonstrate the usefulness of the AFM oxidation process, we first fabricated two-terminal devices that has a periodic modification on the surface layer produced by the AFM oxidation. The devices show prominent magnetoresistance oscillation component different from that of the Shubnikov-de Haas oscillations. The appearance of the additional magnetoresistance oscillations, so called Weiss oscillations, prove the formation periodic potential modulation on the two-dimensional electron gas accumulate
… More
d in the InAs channel layer.
Using this AFM oxidation process, we developed a fabrication process relies on oxidation of GaSb surface layer for the realization of single electron transistors (SETs). Although the island size of the SET was roughly 250 nm in diameter, we confirmed the field effect transistor action and observed the oscillative feature in the transfer characteristics. Theoretical analysis was made to confirm that the oscillation is due to the Coulomb blockade, and we obtained reasonable agreement between the theory and the experiment. In addition, the obtained I-V characteristics implies the interplay between the Coulomb blockade and quantum confinement effects.
Finally, we examined direct oxidation of InAs in order to reduce the fabrication size. This process allows us to eliminate chemical etching processes that limit the minimum achievable size due to the side etching. The minimum line width obtained was 50 nm. This show the promising feature of the AFM oxidation for the achievement of the room temperature operative quantum devices made from InAs/AlGaSb heterostructures. Less
|
