Towards high-performance transistors and photodetectors with monolayer graphene through modified transfer and lithography process
Although there have been plenty of reports about graphene transistors and photodetectors, due to the carbonization of photoresists during Reactive Ion Etching (RIE) process, polymer residue is widely found in graphene devices, which leads to a weak photoresponse and low carrier mobility. On the other hand, doping in ambient conditions also result in mobility deterioration and Dirac point shift in graphene devices. In this paper, a novel lithography process is found to be efficient in alleviating the polymer residue problem. By inserting a diluted Polymethyl methacrylate (PMMA) interlayer between graphene and photoresists, and using sodium hydroxide (NaOH) solution for strapping, the photoresponse of pure monolayer graphene can be as large as 220 mA/W at 1 V bias, which is much larger than previous reports. Furthermore, by introducing an ammonia solution process during the graphene transfer process, the maximum hole mobility of the back-gated graphene transistor can be larger than 8500 cm2V–1s–1, with the Dirac point changed to be near zero. More practically, the mobility exhibits a good stability, which remains high after 20 days in ambient condition. This work provides a feasible route for improving the photoresponsivity and carrier mobility of graphene-based photodetectors.
No Supplementary Data.
No Article Media
Document Type: Short Communication
Publication date: June 1, 2017
More about this publication?
- Materials Express is a peer-reviewed multidisciplinary journal reporting emerging researches on materials science, engineering, technology and biology. Cutting-edge researches on the synthesis, characterization, properties, and applications of a very wide range of materials are covered for broad readership; from physical sciences to life sciences. In particular, the journal aims to report advanced materials with interesting electronic, magnetic, optical, mechanical and catalytic properties for industrial applications.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Ingenta Connect is not responsible for the content or availability of external websites