Chekol Solomon Amsalu, Yoo Jongmyung, Park Jaehyuk, Song Jeonghwan, Sung Changhyuck, Hwang Hyunsang
Department of Material Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea.
Nanotechnology. 2018 Aug 24;29(34):345202. doi: 10.1088/1361-6528/aac9f5. Epub 2018 Jun 4.
In this letter, we demonstrate a new binary ovonic threshold switching (OTS) selector device scalable down to ø30 nm based on C-Te. Our proposed selector device exhibits outstanding performance such as a high switching ratio (I/I > 10), an extremely low off-current (∼1 nA), an extremely fast operating speed of <10 ns (transition time of <2 ns and delay time of <8 ns), high endurance (10), and high thermal stability (>450 °C). The observed high thermal stability is caused by the relatively small atomic size of C, compared to Te, which can effectively suppress the segregation and crystallization of Te in the OTS film. Furthermore, to confirm the functionality of the selector in a crossbar array, we evaluated a 1S-1R device by integrating our OTS device with a ReRAM (resistive random access memory) device. The 1S-1R integrated device exhibits a successful suppression of leakage current at the half-selected cell and shows an excellent read-out margin (>2 word lines) in a fast read operation.
在这封信中，我们展示了一种基于C-Te的新型二元硫系阈值开关（OTS）选择器器件，其可扩展至ø30 nm。我们提出的选择器器件表现出优异的性能，如高开关比（I/I > 10）、极低的关断电流（~1 nA）、<10 ns的极快工作速度（转换时间<2 ns，延迟时间<8 ns）、高耐久性（10）和高热稳定性（>450 °C）。观察到的高热稳定性是由于与Te相比，C的原子尺寸相对较小，这可以有效抑制OTS薄膜中Te的偏析和结晶。此外，为了确认选择器在交叉阵列中的功能，我们通过将我们的OTS器件与电阻式随机存取存储器（ReRAM）器件集成来评估1S-1R器件。1S-1R集成器件在半选单元处成功抑制了漏电流，并在快速读取操作中显示出优异的读出裕度（>2条字线）。
