Laser cuts increase the reliability of heavy-wire bonds and enable on-line process control using thermography. (September 2017)

• Record Type: Journal Article
• Authors: Middendorf, A.; Grams, A.; Janzen, S.; Lang, K.-D.; Wittler, O.
• Is Part Of: Microelectronics and reliability. Volume 76/77(2017)
• Page Start: 450
• Page End: 454
• Publication Date: 2017-09
• Subjects: Heavy wire bond -- Reliability -- Thermography -- Lifetime modelling -- Laser formed trenches; Electronic apparatus and appliances -- Reliability -- Periodicals; Miniature electronic equipment -- Periodicals; Appareils électroniques -- Fiabilité -- Périodiques; Équipement électronique miniaturisé -- Périodiques; Electronic apparatus and appliances -- Reliability; Miniature electronic equipment; Periodicals; 621.3815
• DOI: 10.1016/j.microrel.2017.07.033
• Languages: English
• ISSNs: 0026-2714

Abstract

Abstract: The active thermal cycling lifetime of heavy wire bonds decreases significantly with increasing wire diameter. This paper presents an innovative method for shaping the wire bond in the bonding region such that the thermo-mechanical load on the interface region between wire bond and semiconductor metallization is significantly reduced. The efficiency of the approach has been validated using finite element simulations and power cycling experiments. Moreover, the method can be used as a 'non-destructive' in-situ measurement technique, in which crack growth can be determined based on thermography measurements of the trenches, which act as magnifiers for the thermography camera and eliminate preconditioning such as using black colouring. Highlights: Innovative method for shaping the wire bond in the bonding region such that the lifetime is significantly improved. Quantification of effects on lifetime by first experiments and detailed finite element simulations. 'Non-destructive' in-situ measurement technique for crack growth determination based on thermography measurements.