Fabrication of suspended graphene field-effect transistors by the sandwich method

A novel fabrication technique that can be used for making a series of suspended graphene field-effect transistors on Si-substrate is discussed. The electrical properties of graphene channel can be significantly degraded by defects and chemical residues between graphene and substrate. To minimize electrical degradation, a method of physically suspending graphene from the substrate has been considered while maintaining its structural integrity. To address this problem, we employed a sandwich method to fabricate a suspended GFET, realizing 76% device fabrication yield that is higher than those realized by the other methods. Furthermore, the degradation of electrical properties due to external factors decreased. As our method has a mechanically stable structure, it can be imposed to make electrical devices with various two-dimensional (2D) materials. Our method can also be applied to the engineering of future devices in various applications because a large amount of electrically clean samples can be manufactured at once.

Automated summary

This article discusses a novel fabrication technique for producing suspended graphene field-effect transistors on a Si-substrate. Defects and chemical residues between the graphene and substrate can significantly degrade the electrical properties of the graphene channel. To minimize this degradation, a method of physically suspending the graphene while maintaining its structural integrity has been employed. By using a sandwich method, a suspended GFET with a fabrication yield of 76% has been achieved, higher than other methods. Additionally, the degradation of electrical properties due to external factors has decreased. Our mechanically stable method can be applied to fabricate electrical devices using various two-dimensional (2D) materials, making it useful for future device engineering. A large amount of electrically clean samples can be manufactured simultaneously, making it applicable to various applications.