Patent ID: 7534636
Filing Date: 2009-05-19
Classification: G02B,H01L,H01S

Abstract:
1. A method for forming a lid for a wafer-scale package, comprising: forming a lid cavity having an angled sidewall in a substrate; forming an oxide layer on the substrate over the lid cavity and over a bond area around the lid cavity; forming a reflective layer on the oxide layer, a portion of the reflective layer over the angled sidewall forming a mirror on the angled sidewall for reflecting a light; forming a barrier layer on the reflective layer, the barrier layer being solder-nonwettable, the barrier layer having a thickness less than a quarter wavelength of the light and being transparent to the light; etching a portion of the barrier layer down to the reflective layer over the bond area; and forming a solder layer on the reflective layer within the etched portion of the barrier layer over the bond area, wherein the barrier layer prevents the solder layer from wicking into the lid cavity and affecting said reflecting.