Area-Selective Adhesive Bonding Using Photosensitive BCB for WL CSP Applications

Abstract

This paper reports on an area-selective adhesive wafer bonding, using photosensitive BCB from Dow Co. The strength of the fabricated bonds is characterized using the wedge-opening and tensile methods. The measured fracture toughness is 53.5±3.9 J/m2 with tensile strength up to 71 MPa. The potential application of BCB bonding is demonstrated on a concept of wafer-level chip-scale package for RF applications and microfilter array for microfluidic applications.