-the B.S. degree from Seoul National University in 1976,
-the M.S. degree from the Korea Advanced Institute of Science and Technology in 1978,
-the Ph.D. degree on electrical engineering from the University of Michigan, Ann Arbor in 1987
From 1978 to 1982, he was a senior research engineering at the korea Institute of electronics Technology. From 1987 to 1988, he was a postdoctoral fellow at the IBM T.J. Watson Research Center. Since 1989, he hs been with Seoul National University, where he is now a Professor in the School of Electrical engineering.
-Design & Fabrication of Millimeter wave device/circuit
-Power Amp. with GaN device