- Researcher at Electronics and Telecommunications Research Institute(ETRI) : Involved in Communications Chip Design.
- Senior Design Engineer at Intel Corp., Hillsboro, OR : Involved in Intel Pentium-Pro CPU Design Project, Micro-controller Chip Design.
- Member of Technical Staff at Hewlett Packard Company, Fort Collins, CO : Involved in PA RISC 8000 CPU Chip Design Project.
- Individual Technical Contributor at Sun Microsystems Inc., Sunnyvale, CA: Involved in Ultra SparcV CPU Chip Design Project