Papers by Author: Kwang Seok Seo

Abstract: We have fabricated advanced metal-oxide-semiconductor (MOS) capacitors with ultra thin (5 nm) remote-PECVD SixNy dielectric layers and investigated electrical properties of nitrided SiO2/4H-SiC interface after oxidizing the SixNy in dry oxygen at 1150 °C for 30, 60, 90 min. Improvements of electrical properties have been revealed in capacitance-voltage (C-V) and current density-electrical field (J-E) measurements in comparison with dry oxide. The improvements of SiC MOS capacitors formed by oxidizing the pre-deposited SixNy have been explained in this paper.

Abstract: For flip-chip process of RF system-on-packages(SOP), double bump bonding processes were investigated. Sn-Ag and Sn solder joints were formed by the reflowed double bumping process, and Sn/In/Sn bump joints were fabricated by the non-reflowed double bump bonding process. The height-to-size ratios of 0.78 and 0.65 were obtained for the reflowed double bumping and the non-reflowed bumping, respectively. Average contact resistance of the reflowed Sn-Ag and Sn solder joints was about 13m/ which was much lower than 24~33m/ of the non-reflowed Sn/In/Sn bump joints. The reflowed solder double bumping method is more suitable for flip-chip process of RF-SOP than the non-reflowed double bump bonding.