Research Topics

Artificial Vision & Neural Engineering


01 Electrical/Mechanical Devices for Biological Applications

My research spectrum covers from transistors to retinal neurons, which are basic building blocks of modern electronics and nervous systems, respectively. My Ph.D. thesis work includes the development of a nanowire channel thin-film transistor (TFT), which was the world’s smallest TFT at the time of publication (Im et al., IEEE Elect. Dev. Lett., 2008). In my dissertation, I further explored the use of a similar type of nanowire channel transistors for detection of avian influenza virus (Im et al., IEEE Sensors J., 2011). Another research area in my graduate studies was Micro-Electro Mechanical Systems (MEMS): I developed MEMS devices for diverse applications such as biological assay patterning (Im et al., Appl. Phys. Lett., 2007), super-hydrophobicity (Im et al., Soft Matter, 2010; Im et al., Langmuir, 2010a), and electrowetting (Im et al., Langmuir, 2010b). From these studies, I acquired various hands-on skills for cutting-edge micro-/nano-fabrication research.

During my postdoctoral training at the University of Michigan, I had worked on a more advanced MEMS device with a neural engineering application. For selective excitation of genetically modified neurons using accurately transmitted light (i.e. optogenetics), I had fabricated neural probes with monolithically integrated optical waveguides (Im et al., IEEE MEMS, 2011; Im et al., IEEE EMBC, 2011; Fan et al., J. Neural Eng., 2013). Those neural probes also have integrated microelectrodes for recording neural activities as a precise tool for neuroscience studies. Prior to this type of research, neuroscientists used to manually attach a chemically-thinned optical fiber onto neural probes. It was a good example showing that MEMS devices can provide an enabling technology to neuroscientists for more accurately controlled experiments. During that time, I realized that micro-/nano-fabrication expertise could contribute even further to neuroscience if micro-/nano-fabrication engineers gain fundamental understandings and direct research experience with a specific topic.