基于晶圆级MoS2连续薄膜的场效应管集成工艺与性能提升

Recent exploration of semiconducting two-dimensional transition metal dichalcogenides (2D-TMDs) with atomic thickness has taken both the scientific and technological communities by storm. Extensively investigated 2D-TMDs materials, such as MoS2 that is accessible by large-scale CVD synthetic methods, are remarkably stable and allow superior gate control due to their 2D nature and favorable electronic transport properties, suggesting a bright future for electronic devices. However, a major obstacle preventing such material from practical application is the absence of reliable and repeatable device processing technologies, since 2D-TMDs are radically different from conventional bulk semiconductors (Si, Ge, etc). Thus conventional processing methods are no longer applicable in 2D-TMDs device fabrication. In this research proposal, we will first improve the current wafer-scale CVD synthesis method for MoS2 continuous. Then systematic device processing technologies will be developed for such wafer scale MoS2 continuous film, such as contact engineering, substitution doping and dielectric deposition. The band engineering and scattering mechanisms will also be studied to assist the device processing. The ultimate target is to achieve a thorough solution for high performance wafer scale MoS2 transistors through an overall integration of materials synthesis, isolated processing recipes, band engineering and device modeling, to further promote the development of 2D-TMDs based electronic device application.

近来以MoS2为代表的二维过渡金属硫族化合物（2D-TMDs）引起了广泛的关注，这类材料具有优异的稳定性和半导体性能，而且晶圆级MoS2连续薄膜的CVD的可控制备也已经初步实现，从而为未来电子器件提供了新的材料选择。然而，由于二维材料只有原子级的厚度，而且CVD生长的薄膜缺陷较多，晶畴和晶界的情况也较为复杂，导致传统硅半导体器件的经验往往不再适用。所以晶圆级MoS2连续薄膜的器件工艺目前还不是非常完善。本项目以晶圆级MoS2连续薄膜的CVD制备为基础，探索若干重要的分立器件工艺，诸如源漏接触、掺杂和栅介质沉积等等，同时研究能带和散射机制等关键物性的调控及其科学问题，为工艺优化提供参考和帮助，并最终实现材料制备、器件工艺和集成优化的有机结合。目标是实现晶圆范围的MoS2高性能场效应晶体管阵列，并进一步实现具有功能的简单电路，推动二维材料在信息器件领域的应用。

近来以MoS2为代表的二维过渡金属硫族化合物（2D-TMDs）由于其性能优异而引起了广泛的关注，并且晶圆级MoS2连续薄膜的CVD的可控制备也已经初步实现，从而为未来电子器件提供了新的材料选择。然而，由于二维材料只有原子级的厚度，而且CVD生长的薄膜缺陷较多，晶畴和晶界的情况也较为复杂，导致传统硅半导体器件的经验往往不再适用，所以晶圆级MoS2连续薄膜的器件工艺目前还不是非常完善。本项目以晶圆级MoS2连续薄膜的CVD制备为基础，探索若干重要的分立器件工艺，诸如源漏接触、掺杂和栅介质沉积等等，同时研究能带和散射机制等关键物性的调控及其科学问题，以材料制备、器件工艺和集成优化的有机结合，拓展研究了CVD制备晶圆级PtSe2及其晶体管、P-N结的制备（P型和N型晶体管分别为14和15cm2V−1s−1，开关比为100），并实现晶圆级的MoS2高性能场效应晶体管阵列（平均迁移率达70 cm2V−1s−1，亚阈值摆幅为150 mV dec−1）和双栅晶体管。项目目前已经顺利完成，取得较为丰富的成果：指导4名本科生完成毕业设计，培养毕业研究生3名；在国际及国内学术期刊上发表了7篇学术论文，申请了国内发明专利 2项，项目组参加了5次国际会议报告和2次论坛报告。