Park Jeong-Min, Lee Sein, Lee Junseo, Kwon Jang-Yeon
School of Integrated Technology, Yonsei University, Seoul 03722, Republic of Korea.
BK21 Graduate Program in Intelligent Semiconductor Technology, Yonsei University, Incheon 21983, South Korea.
ACS Omega. 2024 Dec 31;10(1):1006-1011. doi: 10.1021/acsomega.4c08274. eCollection 2025 Jan 14.
We developed a two-transistor, zero-capacitor (2T0C) gain-cell memory featuring a self-aligned top-gate-structured thin-film transistor (TFT) for the first time. The proposed indium tin zinc oxide (ITZO) channel-incorporated architecture was specifically engineered to minimize parasitic capacitance for achieving long-retention 2T0C memory operations. A typical 2T0C structure features five types of parasitic capacitances; however, the proposed SATG design effectively used an essential gate insulator capacitance ( ) and reduced four nonessential capacitances ( , , , and ) to virtually zero. The ITZO-based 2T0C gain-cell memory achieved a retention time >10,000 s owing to the extremely low off-current (2.33 × 10 A/μm), superior positive-bias stability (0.71 V), and high saturation mobility [17.52 cm/(V s)] of the optimized TFT structure. Our proposed memory with long retention and high endurance is a promising solution for next-generation 3D-integrated stacked dynamic random-access memories and defines a new structural standard for future memory architectures.
我们首次开发了一种具有自对准顶栅结构薄膜晶体管（TFT）的双晶体管零电容（2T0C）增益单元存储器。所提出的包含铟锡氧化锌（ITZO）沟道的架构经过专门设计，以最小化寄生电容，从而实现长保持时间的2T0C存储器操作。典型的2T0C结构具有五种类型的寄生电容；然而，所提出的自对准顶栅（SATG）设计有效地利用了基本的栅极绝缘层电容（ ），并将四种非必要电容（ 、 、 和 ）降低到几乎为零。基于ITZO的2T0C增益单元存储器由于优化的TFT结构具有极低的关态电流（2.33×10 A/μm）、优异的正偏压稳定性（0.71 V）和高饱和迁移率[17.52 cm²/(V·s)]，实现了大于1万秒的保持时间。我们提出的具有长保持时间和高耐久性的存储器是下一代3D集成堆叠动态随机存取存储器的一种有前途的解决方案，并为未来的存储器架构定义了一种新的结构标准。
