| 학회 | 한국재료학회 |
| 학술대회 | 2008년 가을 (11/07 ~ 11/07, 차세대융합기술연구원) |
| 권호 | 14권 2호 |
| 발표분야 | 전자재료 |
| 제목 | Electrical property of Al2O3 deposited in low temperature by sputtering process |
| 초록 | Thin film transistor is one of the key technologies for the flat panel displays. The enhancement of TFT performance is the essential to realize the high performance and large area displays. For that reason, many research tried to enhance the TFT performance such as reducing response time, minimizing the fluctuation in the threshold voltage (Vth) and low leakage current. There are studies to change the channel layer. And then several teams have come to the conclusion that one of the best materials for channel layer of TFT is an oxide semiconductor. The oxide semiconductor such as ZnO, SnO, InGaZnO, ZnSnO, InZnO has studied as TFT channel layer materials because of high mobility and excellent uniformity. By attempt to fabricate an oxide semiconductor as the new channel material, the proper gate dielectric materials became important because of the suitability of the insulator and semiconductor interface properties. In this study, the characteristic of Al2O3 thin film as an insulator that has been fabricated on an oxide semiconductor channel layer, SnO channel. The metal–insulator-semiconductor structures were fabricated in order to test the electrical properties of the various conditions Al2O3 gate dielectric. We deposited the Al2O3 thin films on n-type Si substrates using rf magnetron sputtering method by Al2O3 target under the different deposition conditions. And to know the target effects we deposited the Al2O3 thin films by reactive dc magnetron sputtering using the Al target. And then a rapid thermal annealing (RTA) facility was used for rapid annealing of the prepared thin films. To study characteristics of gate dielectric on a Tin oxide semiconductor we deposited the Tin oxide as the semiconductor on high-doped n-type si wafer as the bottom electrode, and then various conditions Al2O3 was deposited as the insulator by sputtering method. Capacitance-voltage and leakage current-voltage were investigated using an HP 4194A impedance analyzer and HP 4140B picoammeter. The best dielectric characteristics of deposited Al2O3 thin films on n-type Si substrate could be obtained by optimized sputtering power and rapid thermal annealing. Al2O3 on the tin oxide substrate had a poor characteristic compared with Al2O3 on Si substrate. We estimated that, the interface property between the insulator and semiconductor was not acceptable for TFTs because of the plasma damage and reaction during sputtering process, It is necessary to improve the interfacial characteristics of Al2O3 thin films on Tin oxide to fabricate and it can be promoted such as low-pressure sputtering method, a rapid thermal annealing (RTA), and damage-free process. |
| 저자 | Bong Seob Yang1, Myung Soo Huh2, Hyeong Joon Kim1 |
| 소속 | 1Department of Materials Science and Engineering, 2Seoul National Univ. |
| 키워드 | Aluminium oxide; sputtering process |
