Deposition of high-k dielectrics on two-dimensional MoS2 is an important process for successful application of the transition-metal dichalcogenides in electronic devices. Here, we show the effect of H2O reactant exposure on monolayer (1L) MoS2 during atomic layer deposition (ALD) of Al2O3. The results showed that the ALD-Al2O3 caused degradation of the performance of 1L MoS2 field effect transistors (FETs) owing to the formation of Mo-O bonding and trapping of H2O molecules at the Al2O3/MoS2 interface. Furthermore, we demonstrated that reduced duration of exposure to H2O reactant and postdeposition annealing were essential to the enhancement of the performance of top-gated 1L MoS2 FETs. The mobility and on/off current ratios were increased by factors of approximately 40 and 103, respectively, with reduced duration of exposure to H2O reactant and with postdeposition annealing.
Bibliographical noteFunding Information:
This work was supported by Korea Evaluation Institute of Industrial Technology (KEIT) funded by the Ministry of Trade, Industry and Energy (MOTIE) (Project No. 10050296, Large scale (Over 8) synthesis and evaluation technology of 2- dimensional chalcogenides for next generation electronic devices). This work was supported by the Center for Integrated Smart Sensors funded by the Ministry of Science, ICT and Future Planning as Global Frontier Project (CISS-2011- 0031848). This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. NRF-2014R1A2A1A11052588). This work was supported by Samsung Display Co., Ltd.
© 2016 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Materials Science(all)