Kim Myeongsun, Ha Jongmin, Kwon Ikhyeon, Han Jae-Hee, Cho Seongjae, Cho Il Hwan
Department of Electronic Engineering, Myongji University, Yongin-si, Gyeonggi-do 17058, Korea.
Department of IT Convergence Engineering, Gachon University, Seongnam-si, Gyeonggi-do 13120, Korea.
Micromachines (Basel). 2018 Nov 7;9(11):581. doi: 10.3390/mi9110581.
These days, the demand on electronic systems operating at high temperature is increasing owing to bursting interest in applications adaptable to harsh environments on earth, as well as in the unpaved spaces in the universe. However, research on memory technologies suitable to high-temperature conditions have been seldom reported yet. In this work, a novel one-transistor dynamic random-access memory (1T DRAM) featuring the device channel with partially inserted wide-bandgap semiconductor material toward the high-temperature application is proposed and designed, and its device performances are investigated with an emphasis at 500 K. The possibilities of the program operation by impact ionization and the erase operation via drift conduction by a properly high drain voltage have been verified through a series of technology computer-aided design (TCAD) device simulations at 500 K. Analyses of the energy-band structures in the hold state reveals that the electrons stored in the channel can be effectively confined and retained by the surrounding thin wide-bandgap semiconductor barriers. Additionally, for more realistic and practical claims, transient characteristics of the proposed volatile memory device have been closely investigated quantifying the programming window and retention time. Although there is an inevitable degradation in state-1/state-0 current ratio compared with the case of room-temperature operation, the high-temperature operation capabilities of the proposed memory device at 500 K have been confirmed to fall into the regime permissible for practical use.
如今，由于对适用于地球上恶劣环境以及宇宙中未开发空间的应用的兴趣激增，对在高温下运行的电子系统的需求正在增加。然而，关于适用于高温条件的存储技术的研究报道仍然很少。在这项工作中，提出并设计了一种新颖的单晶体管动态随机存取存储器（1T DRAM），其器件沟道朝着高温应用方向部分插入了宽带隙半导体材料，并在500K温度下重点研究了其器件性能。通过一系列在500K温度下的技术计算机辅助设计（TCAD）器件模拟，验证了通过碰撞电离进行编程操作以及通过适当高的漏极电压进行漂移传导擦除操作的可能性。对保持状态下能带结构的分析表明，存储在沟道中的电子可以被周围的薄宽带隙半导体势垒有效地限制和保留。此外，为了满足更现实和实际的要求，对所提出的易失性存储器件的瞬态特性进行了深入研究，量化了编程窗口和保持时间。尽管与室温操作相比，状态1/状态0电流比不可避免地会下降，但已证实所提出的存储器件在500K温度下的高温操作能力属于实际应用允许的范围。
