We demonstrate 500 x 500 μm2 large scale polygrain MoS2 nanosheets and field effect transistor (FET) circuits integrated using those nanosheets, which are initially grown on SiO2/p+-Si by chemical vapor deposition but transferred onto glass substrate to be patterned by photolithography. In fact, large scale growth of two-dimensional MoS2 and its conventional way of patterning for integrated devices have remained as one of the unresolved important issues. In the present study, we achieved maximum linear mobility of ∼9 cm2 V-1 s-1 from single-domain MoS2 FET on SiO2/p+-Si substrate and 0.5-3.0 cm2 V-1 s-1 from large scale MoS2 sheet transferred onto glass. Such reduced mobility is attributed to the transfer process-induced wrinkles and crevices, domain boundaries, residue on MoS2, and loss of the back gate-charging effects that might exist due to SiO2/p+-Si substrate. Among 16 MoS2-based FETs, 13 devices successfully work (yield was more than 80%) producing NOT, NOR, and NAND logic circuits. Inverter (NOT gate) shows quite a high voltage gain over 12 at a supply voltage of 5 V, also displaying 60 μs switching speed in kilohertz dynamics.
Bibliographical noteFunding Information:
The authors (H Kwon, P J Jeon, J S Kim and S Im) acknowledge the financial support from NRF (NRL program: Grant No. 2014R1A2A1A01004815), from the Ministry of Trade, Industry and Energy (the Global Leading Technology Program: Grant No. 10042433-2012-11), the Yonsei University (Future-leading Research Initiative of 2014: Grant No. 2014-22-0168), The authors (T-Y Kim and T Lee) appreciate the financial support received from the National Creative Research Laboratory program (Grant No. 2012026372) through the National Research Foundation of Korea (NRF) and Brain Korea 21 plus Program.
© 2016 IOP Publishing Ltd.
- CVD-MoS nanosheet
- Field effect transistor
- Large scale
- Logic circuits