摘要： This study was conducted to investigate the reflectivity and the reflectivity stability of the electroless (Ag) metallization of reflectors used in high-brightness white GaN light-emitting diode packages. Two main reflector metallization schemes were studied: (1) electroless-Ag/electroless-pure-Pd/electroless-Ni plating and (2) electroless-Ag/electroless-Pd(P)/electroless-Ni plating. The reflectivity achieved using all reflector-metallization schemes was >85% in the visible range. However, in the electroless-Ag/electroless-pure-Pd/electroless-Ni reflector, reflectivity exhibited substantial thermal degradation; this was because of two principal factors: (1) the change in the surface morphology of the electroless-Ag surface grains; and (2) the alloying effect on the Ag layer exerted by the interdiffusion occurring with the underlying Pd layer. In this study, P was added to the Pd layer, and the thermal degradation of the annealed electroless-Ag/electroless-Pd(P)/electroless-Ni reflector was measured to be less than that of the electroless-Ag/electroless-pure-Pd/electroless-Ni reflector. The P content retarded the interdiffusion between the Ag and Pd(P) layers and preserved the faceted surface of the electroless-Ag layer, which enhanced the stability of the reflectivity of the electroless-Ag reflector. Furthermore, increasing the thickness of the electroless-Ag layer reduced the amount of Pd diffusing through the Ag layer, which helped retain the reflectivity of the Ag surface. 其他題名： Journal of Elec Materi 出版者： Boston: Springer US 出版日期： 2014-12-01 出處： Journal of electronic materials, 2014-12, Vol.43 (12), p.4602-4609 資源來源： EBSCOhost OmniFile Full Text Select 版權： The Minerals, Metals & Materials Society 2014 版權： Journal of Electronic Materials is a copyright of Springer, 2014. 識別號： ISSN: 0361-5235 識別號： EISSN: 1543-186X 識別號： DOI: 10.1007/s11664-014-3417-6
