Method for measuring fracture toughness of wafer-bonded interfaces with high spatial resolution

Abstract

A test method for adhesion quantification with high spatial resolution of bonded areas is presented. The method is based on a three-point bend chevron test and is applicable especially for small bonded structures. Using an ordinary surface profiler the method is suitable for determining the mode I fracture toughness, KIc, of bonded areas from 5 × 5 µm2 to 20 × 20 µm2 in size. The method is compared quantitatively to the double cantilever beam (DCB) test. Measurements show that the average KIc value determined using this method is in close accordance with KIc values measured using the DCB method but a larger spread is observed which may be dedicated to a real spatial variation of KIc shown by the higher spatial resolution of the presented method.

Low Temperature Plasma-Assisted-Wafer-Bonding for MEMS

“…The simulations show that K I is prevalent. The critical crack length for different geometries and corresponding shape factors for evaluation of the fracture toughness are calculated based on Bluhm´s slice model (8,10,11).…”

Methods for characterization of wafer-level encapsulation applied on silicon to LTCC anodic bonding

“…Recently, research activities in MEMS packaging have been focused on developing low-cost yet robust packaging techniques by investigating new materials such 4 Author to whom any correspondence should be addressed. as low-temperature cofired ceramics (LTCC) and new methods such as room temperature plasma-enhanced bonding [3][4][5].…”

“…Recently, research activities in MEMS packaging have been focused on developing low-cost yet robust packaging techniques by investigating new materials such 4 Author to whom any correspondence should be addressed. as low-temperature cofired ceramics (LTCC) and new methods such as room temperature plasma-enhanced bonding [3][4][5]. The combination of MEMS with LTCC by waferlevel bonding [6] opens up new possibilities for applications and products within microfluidics [7,8], optics [9], microreactors [10] and sensors [11,12].…”

Low Temperature Plasma-Assisted-Wafer-Bonding for MEMS

“…We are developing a test method to characterize small interfaces with high spatial resolution, utilizing small bonded areas of only a few µm 2 , e.g. for the construction of single cell bioreactors [4].…”