Dynamics of Free Air Ball Formation in Thermosonic Wire Bonding

A wire clamp is used to grip a gold wire with in 1–2 ms during thermosonic wire bonding. Modern wire bonders require faster and larger opening wire clamps. In order to simplify the design process and find the key parameters affecting the opening of wire clamps, a model analysis based on energy conservation was developed. The relation between geometric parameters and the amplification ratio was obtained. A finite element (FE) model was also developed in order to calculate the amplification ratio and natural frequency. Experiments were carried out in order to confirm the results of these models. Model studies show that the arm length was the major factor affecting the opening of the wire clamp.

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Effect of Conduction Pre-heating in Au-Al Thermosonic Wire Bonding

Journal of Surface Engineered Materials and Advanced Technology ◽

10.4236/jsemat.2011.13018 ◽

2011 ◽

Vol 01 (03) ◽

pp. 121-124 ◽

Cited By ~ 3

Author(s):

Gurbinder Singh ◽

Othman Mamat

Keyword(s):

Wire Bonding ◽

Thermosonic Wire Bonding

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The optimization of Free Air Ball for Ag alloy wire bonding (IMPACT 2014)

2014 9th International Microsystems, Packaging, Assembly and Circuits Technology Conference (IMPACT) ◽

10.1109/impact.2014.7048405 ◽

2014 ◽

Author(s):

Louis Chen ◽

Frank Huang ◽

Hsiu Chun Li ◽

W C Hsu

Keyword(s):

Wire Bonding ◽

Alloy Wire ◽

Free Air

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Simulation of Wire Bonding Process Using Explicit Fem with Ale Remeshing Technology

Journal of Mechanics ◽

10.1017/jmech.2019.25 ◽

2019 ◽

Vol 36 (1) ◽

pp. 47-54

Author(s):

C. C. Yang ◽

Y. F. Su ◽

Steven Y. Liang ◽

K. N. Chiang

Keyword(s):

Time Integration ◽

Wire Bonding ◽

Bonding Process ◽

Integration Scheme ◽

Arbitrary Lagrangian Eulerian ◽

Cracking Behavior ◽

Free Air ◽

Time Integration Scheme ◽

Time Marching ◽

The Wire

ABSTRACTThermosonic wire bonding is a common fabrication process for connecting devices in electronic packaging. However, when the free air ball (FAB) is compressed onto the I/O pad of the chip during bonding procedure, chip cracking may occur if the contact pressure is too large. This study proposes an effective simulation technique that can predict the wire ball geometry after bonding in an accurate range. The contact force obtained in the simulation can be used for possible die cracking behavior evaluation. The simulation in this study used the explicit time integration scheme to deal with the time marching problem, and the second-order precision arbitrary Lagrangian-Eulerian (ALE) algorithm was used to deal with the large deformation of the wire ball during the bonding process. In addition, the equilibrium smoothing algorithm in LS-DYNA can make the contact behavior and geometry of the bonding wire almost the same as the experiment, which can also significantly reduce the distortion of the mesh geometry after remeshing.

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Development of a thermosonic wire-bonding process for gold wire bonding to copper pads using argon shielding

Journal of Electronic Materials ◽

10.1007/s11664-004-0136-4 ◽

2004 ◽

Vol 33 (4) ◽

pp. 300-311 ◽

Cited By ~ 24

Author(s):

Jong-Ning Aoh ◽

Cheng-Li Chuang

Keyword(s):

Gold Wire ◽

Wire Bonding ◽

Bonding Process ◽

Thermosonic Wire Bonding

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Experimental Study of Kick up Phenomenon in Thermosonic Wire-Bonding

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.160.77 ◽

2012 ◽

Vol 160 ◽

pp. 77-81

Author(s):

Jing Jing Tian ◽

Lei Han

Keyword(s):

Image Processing ◽

Experimental Study ◽

High Speed ◽

Gold Wire ◽

Wire Bonding ◽

Processing Method ◽

Experimental Results ◽

High Speed Camera ◽

Depth Study ◽

Thermosonic Wire Bonding

Kick-up phenomenon during looping is an important factor in thermosonic wire bonding. In this study, the loping process during wire bonding was recorded by using high-speed camera, and wire profiles evolution was obtained from images sequence by image processing method. With a polynomial fitting, the wire loop profiling was described by the curvature changing, and kick-up phenomenon on gold wire was found between the instant of 290th frame(0.0537s) to 380th frame (0.0703s), the change of curvature is divided into three phases, a looping phase, a mutation phase and a kick-up phase. While in the kick-up phase, the kick up phenomenon is the most obvious. These experimental results were useful for in-depth study of kick-up phenomenon by simulation.

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