Inducing stable interfacial delamination in a multilayer system by four-point bending of microbridges

Abstract

The ability to produce stable delamination of thin film multilayer interfaces is a powerful tool for studying the interfacial adhesion within microsystems. In this study, a technique involving the four-point bending of microbridges was applied to initiate stable interfacial delamination within a multilayer system. Microscale pre-notched bridges with clamped-ends were machined into an Al/SiN/GaAs multilayer using focus ion beam milling. A square flat-end indenter was used to induce bending of the bridge by two contact locations. Bridge failure occurred via substrate fracture at the pre-notch, followed by crack deflection, and stable interfacial delamination of the SiN/GaAs interface. Substrate fracture and delamination were identified within the obtained load-displacement curves as a pop-in and region of linear load reduction respectively.

Interfacial adhesion assessment of SiN/GaAs film/substrate system using microcantilever bending technique

“…Three dimensional (3D) linear-elastic models of the cantilevers were developed using ANSYS 19.1. The interface was assumed to be fully coherent with no transition zone between neighbouring material components [18]. Tetrahedral elements were used to mesh the microcantilevers, as shown in figure 3(a).…”

“…These * Author to whom any correspondence should be addressed. include tape peel [2,11,12], pull-off [13,14], stressed-overlayer [6,15], scratch [16,17], bending [18][19][20], and nanoindentation tests [2,9,21,22]. Tape peel and pull-off tests are easy to apply.…”

Adhesion Evaluation of an Embedded SiN/GaAs Interface Using a Novel “Push-Out” Technique

“…Various micro-mechanical testing techniques have been developed to characterize interfacial adhesion. Nanoindentation [ 8 , 9 , 10 , 11 , 12 ], nanoscratch [ 13 , 14 ], and micro-cantilever (MC) and micro-bridge (MB) bending [ 7 , 15 , 16 , 17 , 18 ] are widely used. From these, nanoscratch is considered to be a semi-quantitative approach [ 19 ], whereas top-surface nanoindentation has been used to measure the interfacial strength and toughness of a stiff dielectric film attached onto a comparatively ductile semiconductor substrate [ 19 , 20 ].…”

“…From these, nanoscratch is considered to be a semi-quantitative approach [ 19 ], whereas top-surface nanoindentation has been used to measure the interfacial strength and toughness of a stiff dielectric film attached onto a comparatively ductile semiconductor substrate [ 19 , 20 ]. MC and MB bending tests have been used to evaluate interfacial toughness, both applicable to embedded interfaces [ 7 , 15 , 17 ]. However, the suitability of MC and MB bending is limited to the interface of a stiff film on an ideally stiff substrate [ 18 ], as bending induced plastic deformation in ductile layers could prevent interfacial delamination from occurring or introduce additional complexity and substantial error to the analysis [ 21 ].…”

Repeated Laser Shock-Wave Adhesion Test for Metallic Coatings: Adhesion Durability and Its Mechanism Studied by Molecular Dynamics Simulation

“…Therefore, it is important to evaluate the adhesion strength of the coating, especially the adhesion durability when it is subjected to cyclic loading. Previously, various tests such as the uniaxial tensile test [6][7][8] and the fourpoint bending test [9,10] have been used to investigate adhesion strength and durability. In uniaxial tensile testing, cylindrical specimens are adhered together with an adhesive and subjected to uniaxial loading.…”