Papers by Author: Woo Young Lee

Abstract: The hydrogen permeation properties of the Pd-coated Ni37.5Nb27.5Zr25Co5Ta5 amorphous membranes have been investigated at 673 and 723K for 720 hours (1 month). Values of the hydrogen permeability during these long term tests were found to be reduced of about 50 and 30 % at 673 and 723K, respectively. The reduction in the hydrogen permeability could be correlated to the change in the composition of the coating as well as at the interface between Pd coating and Ni-based amorphous membrane.

Abstract: A novel process of wafer bonding between InP and a garnet crystal (Gd3Ga5O12, CeY2Fe5O12) based on O2 plasma surface-activation and low temperature heat treatment is presented. The O2 plasma assisted wafer bonding process was found to be very effective in bonding of InP and Gd3Ga5O12, providing good bonding strength and hydrophilicity as well as no voids in the interface, which is crucial for fabrication of an integrated optical waveguide isolator. The isolation ratio of an integrated optical waveguide isolator fabricated by the O2 plasma assisted wafer bonding process was obtained to be 2.9 dB.