Two dimensional(2D) crystals, composed of a single layer or a few atomic layers extracted from layered materials are attracting researchers’ interest due to promising applications in the nanoelectromechanical systems. Worldwide researchers are preparing devices with suspended 2D materials to study their physical and electrical properties. However, during the fabrication process of 2D flakes on a target substrate, contamination occurs, which makes the measurement data less reliable. We propose a dry transfer method using poly-methyl methacrylate(PMMA) for the 2D flakes to transfer onto the targeted substrate. The PMMA is then removed from the device by an N-Methyl-2-pyrrolidone solution and a critical point dryer, which makes the suspended 2D flakes residue free. Our method provides a clean, reliable and controllable way of fabricating micrometer-sized suspended 2D nanosheets.

Abstract
 1. Introduction
 2. Experimental Details
 3. Results and Discussion
 4. Conclusions
 References

• Rakesh Sadanand Sharbidre(Department of Material Science Engineering, Paichai University, Division of Industrial Metrology, Korea Research Institute of Standards and Science)
• Ji Cheol Byen(Department of Material Science Engineering, Paichai University)
• Gyeong Yeol Yun(Department of Material Science Engineering, Paichai University)
• Jae-Kyung Ryu(Department of Dental Technology and Science, ShinHan University)
• Chang Jun Lee(Division of Industrial Metrology, Korea Research Institute of Standards and Science, School of Mechanical Engineering, Chonnam National University)
• Seong-Gu Hong(Division of Industrial Metrology, Korea Research Institute of Standards and Science, Department of Nano Science, University of Science and Technology)
• Sachin Bramhe(Department of Material Science Engineering, Paichai University)
• Taik Nam Kim(Department of Material Science Engineering, Paichai University) Corresponding author