Wire bonding optimization with fine copper wire for volume production

Yauw, Oranna; Clauberg, Horst; Lee, Kuan Fang; Shen, Liming; Chylak, Bob

doi:10.1109/eptc.2010.5702685

Cited by 21 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After consulting the literature, it is found that the distribution position of Pd on the FAB has a great relationship with the EFO discharge current, and scholars have conducted in-depth research on it. Yauw et al [ 35 ] used 0.8 mil PdCu wire and set three EFO discharge currents (30, 60, and 90 mA) to study the distribution of Pd on FAB. The results showed that under a low EFO discharge current, there was a thick Pd layer on the surface of FAB, while a small amount of Pd was distributed at the core of FAB ( Figure 8 a).…”

Section: The Distribution Of Pd In Fab and Bonding Interfacementioning

confidence: 99%

See 1 more Smart Citation

Research Progress of Palladium-Plated Copper Bonding Wire in Microelectronic Packaging

Zhang,

Guo,

Cao

et al. 2023

Micromachines

View full text Add to dashboard Cite

Wire-bonding technology is the most commonly used chip interconnection technology in microelectronic packaging. Metal bonding wire is the key material for wire bonding and plays an important role in the reliability of electronic devices. In recent years, palladium-plated copper (PdCu) bonding wire has been widely used because of its low cost, good electrical and thermal conductivity, the fact that it is not easy to oxidize, and its high reliability. Therefore, it is necessary to review its research progress. In this paper, the preparation and application of palladium-plated copper bonding wire are reviewed. Firstly, the preparation methods of electroplating, electroless plating, and direct plating are introduced. Secondly, the factors affecting the distribution of Pd in free air balls and bonding interfaces, the effect of Pd on the formation and growth of intermetallic compounds in PdCu wire, stitch bond, and reliability of PdCu wire are summarized and analyzed in the application process. Finally, its development prospect is prospected. Hopefully, this review can help readers to have a comprehensive understanding of the preparation and application of palladium-plated copper bonding wires, and can accelerate the promotion of its application in more fields in the future.

show abstract

Section: The Distribution Of Pd In Fab and Bonding Interfacementioning

confidence: 99%

“… The optical images of FAB formed at EFO currents ( a ) 30 mA, ( b ) 60 mA, and ( c ) 90 mA showing different distributions of Pd [ 35 ]. Copyright, 2010, IEEE.…”

Section: Figurementioning

confidence: 99%

Research Progress of Palladium-Plated Copper Bonding Wire in Microelectronic Packaging

Zhang,

Guo,

Cao

et al. 2023

Micromachines

View full text Add to dashboard Cite

show abstract

“…More and more attention is paid to Cu wire bonding due to its low cost and excellent material performance of Cu, and it has gradually become the main material of wire bonding while replacing gold wire [1]. Compared with bare Cu wire, Pd-Cu wire gets more extensive application, the Pd-coated layer protection from corrosion in the bonding process may play an important role [2].…”

Section: Introductionmentioning

confidence: 99%

Investigation of palladium coverage on free air balls of palladium-coated copper wires

Wang

et al. 2012

2012 13th International Conference on Electronic Packaging Technology &Amp; High Density Packaging

View full text Add to dashboard Cite

Recently, copper wire bonding has been given increasing attention due to its low cost and excellent material performance. Compared with pure copper wire, Palladium coated copper (Pd-Cu) wire gets more extensive application partly due to the Pd-coated layer protection for Cu FAB from oxidation in the bonding process. Therefore the research of Pd coverage on free air balls (FAB) is an important aspect for Pd Cu wires. FAB of Pd-Cu wires may have exposed Cu region on top side of F AB where it is to be bonded, this Pd uncovered part could be possibly extended and then exposed to the outside of bonding area. After mold encapsulation, the exposed Cu region on FAB may have higher risk to be subject to corrosion compared with the Pd covered region and lead to failure of fIrst bonding. This paper presents a study for Pd coverage issues on FAB of 0.8mil Pd-Cu wires. A chemical etching method with FeCI3 solution for FAB was adopted to analyze the Pd coverage on FAB. The etching condition had been optimized through careful examinations on the surface morphology of etched FAB. With various FAB forming process parameters, e.g., electronic flame-off (EFO) current intensity and heating, Pd coverage has been studied. The Cu exposure, before and after FAB formation, was also compared and analyzed. This analysis results will provide an important reference for the optimizing FAB process parameters in Cu wire bonding process.

show abstract

“…This greatly increased needs to understand the potential risks associated with copper wire bonding process such as pad peeling, underpad dielectric cracks and/or metal lift. Several papers have reported that the Cu wire bond parameter optimization can reduce pad stress in Cu wire bond [1,2] , and some papers studied the pad structure effects on Cu wire bond [3] , and on BEOL film intrinsic stresses [4] .…”

Section: Introductionmentioning

confidence: 99%

Impact of 40nm BEOL Film Stack on Cu Wire Bond Wire Pull Performance

Yang

Chen

et al. 2013

ECS Trans.

View full text Add to dashboard Cite

Cu wire bond has been widely adopted instead of Au as the choice of wire-bond material mainly for high electrical performance and lower cost. However, Cu wire-bond means greater bond stress than Au wire-bond to the under layer BEOL film stacks, particularly for low K or ultra low K dielectric materials used in advanced nodes for better BEOL RC delay performance. In this work, we used Cu wire pull failure rate as an index to study and optimize the BEOL film stack. In addition, we also studied the Cu wire-bond conditions on the wire-pull performance to find the optimized bond condition. Robust process condition with improved Cu wire-pull performance has been achieved that can meet the 40nm Cu wire-bond requirements. The improved BEOL film stacks and process has passed all the process and product qualifications and implemented as the baseline process for SMIC's 40nm-node high volume production.

show abstract

Wire bonding optimization with fine copper wire for volume production

Cited by 21 publications

References 4 publications

Research Progress of Palladium-Plated Copper Bonding Wire in Microelectronic Packaging

Research Progress of Palladium-Plated Copper Bonding Wire in Microelectronic Packaging

Investigation of palladium coverage on free air balls of palladium-coated copper wires

Impact of 40nm BEOL Film Stack on Cu Wire Bond Wire Pull Performance

Contact Info

Product

Resources

About