中文摘要：

认识到在 graphene 和金属电极之间的低接触抵抗为造高效的 graphene 设备仍然是著名挑战。在这个工作，我们试图在 graphene 晶体管减少接触抵抗并且进一步探索在 graphene 和金属接触之间的抵抗限制。在房间温度的 Pd/graphene 接触抵抗在 100 ?? 下面被减少 ? ?? 汣獡 ? 愢瀭畬 ? 汰獵?? 猯'T ￣慮潮慰瑲捩敬 ? 敤潣慲整 ? 湯吠佩猼'T 挠慬獳∽ ? 汰獵瀭畬 ? 资 ? ?? 渠湡景扩牥 ? 湥 'L 敬 ? 桴 ? ?捣獥晳汵椠瑮来慲楴湯漠 ? 桴 ? 楢慮祲挠浯潰楳整椠瑮 ? 慢瑴牥敩 ? 潴愠摤敲獳猠牴 ' 壮霊 `? 瑳 'L 汩瑩 ? 湡 ? 潬 ? 慣慰楣吗？

英文摘要：

Realizing low contact resistance between graphene and metal electrodes remains a well-known challenge for building high-performance graphene devices. In this work, we attempt to reduce the contact resistance in graphene transistors and further explore the resistance limit between graphene and metal contacts. The Pd/graphene contact resistance at room temperature is reduced below the 100 Ω·μm level both on mechanically exfoliated and chemical-vapor-deposition graphene by adopting high-purity palladium and high-quality graphene and controlling the fabrication process to not contaminate the interface. After excluding the parasitic series resistances from the measurement system and electrodes, the retrieved contact resistance is shown to be systematically and statistically less than 100 Ω·μm, with a minimum value of 69 Ω·μm, which is very close to the theoretical limit. Furthermore, the contact resistance shows no clear dependence on temperature in the range of 77-300 K; this is attributed to the saturation of carrier injection efficiency between graphene and Pd owing to the high quality of the graphene samples used, which have a sufficiently long carrier mean-free-path.