Research on Transfer-Free Graphene Field-Effect Transistors Made by Plasma-Enhanced Chemical Vapor Deposition

Traditional three-dimensional (3D) suffer from the surface roughness is large and the suspension bond is increased when the structure is thinned to a certain extent, which seriously affects the semiconductor performance. Lower dimensional two-dimensional (2D) materials show their excellent properties, opening up a new field for the research of semiconductor processes and devices. Graphene as a representative 2D material, has a stable lattice structure, only one carbon atom thickness, high flexibility, high transparency and high mobility, the mobility is much higher than that of traditional 3D materials, up to 200,000 cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>. y-l. s'. Graphene is considered to be the ideal channel material for manufacturing high-speed field-effect transistors (FETs). In this paper, graphene were grown by plasma-enhanced chemical vapor deposition (PECVD) with transfer-free. And graphene FETs (GFETs) made by transfer-free graphene on GaN-based substrate were designed, fabricated and measured. The method of growing graphene with plasma enhanced and metal assistance has the advantages of fast growth rate, low temperature, complete film coverage, less doping, and enables in-situ and patterned growth on the device directly, which has a very promising research prospect. The thin-film morphology of graphene is compatible with current semiconductor processes and can extend from GFETs to other 2D material transistors, ensuring good repeatability and scalability. Meanwhile, the GFETs fabricated on GaN makes it possible to drive LEDs on the same substrate in the future.