Abstract:
Two-dimensional (2D) transitional metal dichalcogenides (TMDs) have garnered significant attention due to their potential for next-generation electronics, which require device scaling. However, the performance of TMD-based field-effect transistors (FETs) is greatly limited by the contact resistance. This study develops an effective strategy to optimize the contact resistance of WSe2 FETs by combining contact doping and 2D metallic electrode materials. The contact regions were doped using a laser, and the metallic TaSe2 flakes were stacked on doped WSe2 as electrodes. Doping the contact areas decreases the depletion width, while introducing the TaSe2 contact results in a lower Schottky barrier. This method significantly improves the electrical performance of the WSe2 FETs. The doped WSe2/TaSe2 contact exhibits an ultralow Schottky barrier height of 65 meV and a contact resistance of 11 kΩ·μm, which is a 50-fold reduction compared to the conventional Cr/Au contact. Our method offers a way on fabricating high-performance 2D FETs.
摘要:
二维(2D)过渡金属二硫属化合物(TMD)由于其在下一代电子产品中的潜力而引起了广泛关注。这需要设备缩放。然而,基于TMD的场效应晶体管(FET)的性能受到接触电阻的极大限制。本研究开发了一种有效的策略,通过结合接触掺杂和2D金属电极材料来优化WSe2FET的接触电阻。使用激光掺杂接触区,并且将金属TaSe2薄片堆叠在掺杂的WSe2上作为电极。掺杂接触区域会减小耗尽宽度,而引入TaSe2接触导致较低的肖特基势垒。该方法显著改善了WSe2FET的电性能。掺杂的WSe2/TaSe2接触具有65meV的超低肖特基势垒高度和11kΩ·μm的接触电阻,与传统的Cr/Au接触相比减少了50倍。我们的方法提供了一种制造高性能2DFET的方法。