2019 Fiscal Year Annual Research Report
ダンベル型グラフェンナノリボンの電子物性解析に基づく高感度ひずみセンサの開発
| Project/Area Number |
19J12755
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
張 秦強 東北大学, 工学研究科, 特別研究員(DC2)
|
|---|
| Project Period (FY) |
2019-04-25 – 2021-03-31
|
| Keywords | dumbbell-shape structure / graphene nanoribbon / localized properties / strain sensor |
|---|
| Outline of Annual Research Achievements |
The smooth-electron-flow contact between metal electrode and semiconductor is indispensable for fabricating highly sensitive and reliable semiconductor electronic devices. Less complex and energy-consuming fabricating processes for high-performance strain sensors consisting of only carbon atoms should be realized by using a new proposed dumbbell-shape graphene nanoribbon (GNR). The dumbbell-shape GNR has a narrow GNR in the center part with two wide GNRs jointed to both ends of the narrow GNR. Since its electronic properties can be varied from metallic-like one to semiconductive-like one by only engineering its width or length. Hence, the electronic properties of the conjunction area between a wide part as a metallic electrode and narrow part as a semiconductor in the dumbbell-shape GNR were investigated by using first-principles calculations. The electron orbital distribution revealed a localized pattern at the wide part of the dumbbell-shape GNR. It indicates that the electronic properties of the structure show metallic-like ones in the wide part but semiconductive-like ones in the narrow part. Furthermore, the distribution exhibits a smooth spatial gradient from metallic-like one to semiconductive-like one in the dumbbell-shape GNR. Moreover, the current-voltage characteristics through the dumbbell-shape GNR were evaluated and the results confirmed that semiconductive-like properties exist in the dumbbell-shape GNR. Therefore, the proposed dumbbell-shape GNR has great potential for achieving high-performance GNR based strain sensors.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
I have successfully obtained the results as were written in the proposed research plan within this year. At the beginning of this year, it was not very smooth for research activities. I started to code several scripts from the beginning for obtaining specific results that there were no methods to obtain appropriate results before. The scripts were optimized several times to collect reliable results. At present, massive data can be obtained with less required commands. During this year, the experimental equipment for synthesizing large areas and high-quality graphene was also upgraded successfully. It enhanced the reliability of the following fabricating processes.
|
| Strategy for Future Research Activity |
To contribute my research work to the mechanical engineering field, I will simulate the proposed structure with practical conditions, such as defects, applied uniaxial tensile strain, and doping properties. The evaluation of the current-voltage characteristics by first-principles calculations is indispensable for predicting the performance of electronic devices. The parameters of calculation will be optimized further for obtaining more reliable simulation results which will provide a more concrete guide for accelerating the fabrication of dumbbell-shape GNR based strain sensors.
Moreover, I will develop a new fabricating process to decrease the damage introduced into devices for achieving highly sensitive and reliable strain sensors.
|
