单晶石墨烯射频机械开关研究

Radio frequency (RF) mechanical switch is a very important research area of MEMS (Micro-Electro-Mechanical systems). The discovery of graphene provides an opportunity of breaking the bottleneck of the development of RF MEMS, and realizing high performance devices with smaller driving voltage and faster speed. However, large area graphene derived from current methods are polycrystalline. With the influence of grain boundary, most of graphene’s good properties degrade dramatically, having a detrimental effect on device performance (the device is very easy to break down). In this project, a new method was proposed to use artificial seeds to precisely control the location of each single-crystalline graphene grain's growth. Large-area of single-crystalline graphene arrays can be realized, and protect MEMS devices from grain boundaries. Single-crystalline graphene is introduced to MEMS area for the first time, and believed to be able to promote the performance of RF MEMS switch drastically because of its superb properties.

射频（Radio frequency, RF）机械开关是微机电系统（Micro-Electro-Mechanical systems，MEMS）领域中的一个重要研究方向。新材料石墨烯的出现为突破传统RF MEMS开关发展的瓶颈，实现驱动电压更小、速度更快的高性能微纳器件提供了可能性。然而目前方法得到的大面积石墨烯均为多晶结构，晶界的存在极大影响了器件的性能（例如器件极易断裂失效），成为现今影响石墨烯技术发展的一个重要障碍。本项目拟采用植入晶核的方法精确控制每片单晶石墨烯的生长位置，有效防止器件中存在晶界，得到大面积单晶石墨烯器件阵列。本项目首次将单晶石墨烯引入MEMS领域，并将其应用于射频器件，探索单晶石墨烯在RF MEMS开关中的应用，利用其卓越的材料特性进一步提升器件性能。

射频机械开关是微机电系统（MEMS）领域中的一个重要研究方向。新材料石墨烯的出现为突破传统RF MEMS开关发展的瓶颈，实现驱动电压更小、速度更快的高性能微纳器件提供了可能性。然而目前方法得到的大面积石墨烯均为多晶结构，晶界的存在极大影响了器件的性能（器件极易断裂失效），成为目前影响石墨烯技术发展的一个重要障碍。本项目采用植入晶核的方法精确控制每片单晶石墨烯的生长位置，有效防止了器件中存在晶界，得到大面积单晶石墨烯器件阵列。本项目将单晶石墨烯引入MEMS领域，并将其应用于射频器件，探索单晶石墨烯在RF MEMS开关中的应用，利用其优良的材料特性进一步提升了器件性能。单晶石墨烯RF MEMS开关的吸合电压1 V、开关时间100 ns、寿命大于22,000次、40 GHz的隔离度达到-30 dB。