| 학회 | 한국재료학회 |
| 학술대회 | 2011년 가을 (10/27 ~ 10/29, 신라대학교) |
| 권호 | 17권 2호 |
| 발표분야 | F. Display and optic Materials and processing(디스플레이 및 광재료) |
| 제목 | Improvement in the bias stability of IGZO thin film transistors using Al2O3 buffer layer growth on Si3N4 dielectric layer |
| 초록 | Recently, the use of metal oxides as a channel layer in thin film transistors (TFTs) has attracted much attention in the field of advanced electronic devices due to their high mobility and transparency compared to those of conventional amorphous Si. Among the metal oxides, amorphous indium–gallium–zinc oxide (IGZO) has particularly emerged as a key material for high performance backplanes because it provides better uniformity in such device characteristics as threshold voltage and mobility. However, the instability of the device characteristics of these TFTs under negative gate bias stress with light illumination(NBIS) still remains one of the most critical issues that need to be resolved considering the operation mode of the display devices. In recent, it has been reported that manipulation of the valence band offset between high-k dielectrics and IGZO are applied to hole injection barrier for solving the NBIS issues. In general, the high-k dielectrics in TFTs play an important role in increasing the capacitive coupling between the gate and active layer, leading to an improvement in the subthreshold swing and the operation voltage range. However, very little is known about the unintentional effect of high-k dielectrics, such as the field-effect mobility degradation of oxide transistors. In this study, we will discuss the effect of changing in the thickness of high-k Al2O3 layer on the electrical properties of IGZO-TFTs. Al2O3 films (5, 10, 15 and 20 nm) were deposited on 100 nm Si3N4 film by remote plasma enhanced atomic layer deposition (RPALD). A 70 nm-thick IGZO film as an active layer was deposited using RF plasma sputtering. Source/drain electrodes comprised of Ti/Au (30/100 nm) were deposited by an e-beam evaporator. Passivation layer is deposited 50 nm Al2O3 by RPALD. The change in their transfer characteristics under NBITS and the temperature-dependent mobility behavior will examine and be presented. |
| 저자 | 박주현, 방석환, 이승준, 고영빈, 최학영, 신석윤, 김지훈, 함기열, 이상헌, 전형탁 |
| 소속 | 한양대 |
| 키워드 | IGZO; TFT; Atomic layer deposition |
