Enhanced process development by simulation of ultrasonic heavy wire bonding / von Reinhard Schemmel, M. Sc. ; Referent: Prof. Dr.-Ing. habil. Walter Sextro, Korreferent: Prof. Dr.-Ing. habil. Gunter Kullmer. Paderborn, 2022
Content
Nomenclature
Introduction
State of the art
Phenomenological description of the bond formation process
Factors affecting bond quality
Equipment and methods of process development in heavy wire bonding
Modelling and simulation of the wire bond process
Knowledge gap in ultrasonic heavy wire bonding
Ultrasonic heavy wire bonding experiments
Impact of the touchdown force
Design of Experiment
Impact of substructure resonances and bond frequency
Multi scale model of the heavy wire bond process
Model parameter identification
Test rig for low frequency wire bonding experiments
Coefficients of friction between tool, wire and substrate
Bond formation model parameters
Material behaviour of the bond wire under static and ultrasonic load
Shear strength of the bond wire
Tangential wire stiffness
Overview of the model parameters
Validation of the wire bond model
Setup for the simulation
Simulation of the parameter studies
Additional simulation results
Interpretation of the simulation results
Conclusion and suggested future work
Reference
Appendix
Additional shear codes from the wire bonding experiments
Material properties for the modal analysis of the substrate model
Program structure for high performance computing
High performance computing results
Literature values for the material parameters of aluminium an copper
Control system of the test rig for identification of the model parameters
Comparison between simulated and measured shear force values for bond model parameter identification
Comparison between simulated and measured tool substrate contacts