| 학회 | 한국재료학회 |
| 학술대회 | 2019년 가을 (10/30 ~ 11/01, 삼척 쏠비치 호텔&리조트) |
| 권호 | 25권 2호 |
| 발표분야 | A. 전자/반도체 재료 분과 |
| 제목 | Contact engineering for TMD transistor with interfacial layer |
| 초록 | 2-dimensional (2D) transition metal dichalcogenide (TMD) is an emerging semiconductor material with interesting properties such as atomic-flat nature, high scalability, flexibility, and excellent electrical properties. Therefore, there have been various demonstrations for electronic applications. However, to use TMD for practical devices, there are still several issues including achievement of continuous large-area high-quality film growth, high-quality dielectric layer deposition on TMD, and reduction in resistance at metal/semiconductor contact. Especially, high contact resistance is an important concern that has to be preferentially resolved since it would be larger than channel resistance as the scaling is progressed. High contact resistance is usually attributed to the interface states between the contact metal and the semiconductor. To reduce the interface, inserting a thin insulating buffer layer is an effective way. Employing an insulating buffer layer can have two benefits; 1) reduction in contact resistance, 2) achievement of more stable device performance. In this study, we conducted experiments to study contact resistance and device stabilization by using an interfacial layer. A TiO2 insulating buffer layer was used to reduce the interface states at contact. Deposited TiO2 layer was observed in HRTEM cross-sectional image and Ti and O atoms were observed in the energy dispersive spectroscopy (EDS), showing that a thin TiO2 layer can be well deposited on TMD. We found that improved electrical performances can be achieved by inserting an insulating layer. With using a TiO2 layer, effective barrier height was reduced, and as a result, reduced contact resistance value was achieved. In order to observe the instability of TMD FETs, long time stress measurement was conducted. Conventional stress-measure-stress method was used with bias stress on the gate terminal for 10000s. TMD FETs with a TiO2 layer showed more stable performances, exhibiting less shift of threshold voltage (VTH) and field-effect mobility (μFE). |
| 저자 | 박우진, 조병진 |
| 소속 | 충북대 |
| 키워드 | TMD; Contact; Interlayer |
