@article{Nanomaterials:2100,
      recid = {2100},
      author = {Li, Jiajing},
      title = {Directed Assembly of Functional Nanomaterials Using  Chemical Patterns},
      publisher = {The University of Chicago},
      school = {Ph.D.},
      address = {2019-12},
      pages = {110},
      abstract = {Nanomaterials have generated intense interest due to their  novel properties which open up numerous opportunities in  fundamental and applied nanophotonics, nanoelectronics, and  nanomagnetics. However, these materials are generally  processed in the solution phase, and a reliable way to  transfer them from solution to surface with full  addressability remains elusive, thereby limiting the  technological usefulness of such materials. To address this  issue, we propose to control the assembly of nanomaterials  on surface using chemical pattern, which is a  lithographically defined pattern with chemical contract.  The patterned areas and unpatterned areas are  functionalized with different surface chemistry, creating  the necessary chemical contrast to selectively immobilize  the nanomaterials on specific areas. Depending on different  types of materials, a wide range of functions and  applications can be realized using this chemical pattern  technique. 

In this thesis, we demonstrate the possibility  of combing chemical pattern with three different materials  – block copolymer, gold nanoparticle and nanodiamond. The  first chapter introduces basic concept of chemical pattern  and its advantages, followed by Chapter 2 focusing on  directed self-assembly (DSA) of block copolymers (BCPs) for  lithography applications. We demonstrate line/space pattern  with sub-10 nm half pitch with a polymeric additive added  to the BCP. Chapter 3 and 4 investigate kinetics of defect  annihilation in DSA in the hope of further reducing the  defect density. Physical models have been developed to  describe the annihilation kinetics through extensive  statistical analysis and image processing. Chapter 5  demonstrates a hierarchical assembly approach of gold  nanoparticle heterodimers combining chemical pattern and  DNA directed assembly. The gap size of assembled  heterodimers is in the sub-5 nm regime with sub-nm  variance, making them excellent candidate for surface  enhanced Raman scattering (SERS) substrate. Finally, we  briefly introduce a flexible platform of patterned  nanodiamonds for microscale-resolution thermal mapping in  Chapter 6. The temperature sensing capacity of this  platform has been confirmed with simulation results. The  chemical pattern technique is expected to hold a lot more  potentials in many other material systems for further  applications.},
      url = {http://knowledge.uchicago.edu/record/2100},
      doi = {https://doi.org/10.6082/uchicago.2100},
}