1. Department of Electrical Engineering, Stanford University, Stanford, CA, USA.
2. Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
3. Department of Materials Science and Engineering, Seoul National University, Seoul, South Korea.
4. Institute of Photoelectronic Thin Film Devices and Technology, Nankai University, Tianjin, China.
5. Department of Bioengineering, Stanford University, Stanford, CA, USA.
6. Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
7. Department of Chemical Engineering, Kyung Hee University, Yongin, South Korea.