1. Frederick Seitz Materials Research Laboratory, Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
2. Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL 60208, USA.
3. Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
4. Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
5. AML, Department of Engineering Mechanics, Interdisciplinary Research Center for Flexible Electronics Technology, Tsinghua University, Beijing 100084, China.
6. Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
7. Departments of Civil and Environmental Engineering, Mechanical Engineering, and Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
8. Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
9. Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
10. Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
11. Northwestern University Micro/Nano Fabrication Facility (NUFAB), Northwestern University, Evanston, IL 60208, USA.
12. Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.