Radu Iuliana P, Govoreanu B, Mertens S, Shi X, Cantoro M, Schaekers M, Jurczak M, De Gendt S, Stesmans A, Kittl J A, Heyns M, Martens K
IMEC, Kapeldreef 75, Leuven, Belgium. Department of Physics, KU Leuven, Celestijnenlaan 200D, Leuven, Belgium.
Nanotechnology. 2015 Apr 24;26(16):165202. doi: 10.1088/0957-4484/26/16/165202. Epub 2015 Mar 27.
Two-terminal thin film VO2 devices show an abrupt decrease of resistance when the current or voltage applied exceeds a threshold value. This phenomenon is often described as a field-induced metal-insulator transition. We fabricate nano-scale devices with different electrode separations down to 100 nm and study how the dc switching voltage and current depend on device size and temperature. Our observations are consistent with a Joule heating mechanism governing the switching. Pulsed measurements show a switching time to the high resistance state of the order of one hundred nanoseconds, consistent with heat dissipation time. In spite of the Joule heating mechanism which is expected to induce device degradation, devices can be switched for more than 10(10) cycles making VO2 a promising material for nanoelectronic applications.
两终端薄膜VO₂器件在施加的电流或电压超过阈值时会出现电阻突然下降的情况。这种现象通常被描述为场致金属-绝缘体转变。我们制造了电极间距低至100 nm的不同纳米级器件，并研究直流开关电压和电流如何依赖于器件尺寸和温度。我们的观察结果与控制开关的焦耳热机制一致。脉冲测量显示，进入高电阻状态的开关时间约为一百纳秒，这与热耗散时间一致。尽管焦耳热机制预计会导致器件退化，但器件仍可进行超过10¹⁰次的开关循环，这使得VO₂成为纳米电子应用中有前景的材料。
