PDC 1 -- Wire Bonding
Lee Levine, Consultant
Process Solutions Consulting
8009 George Road,
New Tripoli, Pa 18066
In 2008 more than 10^13 semiconductor interconnects were produced. Of this quantity, more than 90% were wire bonds. Wire bonding is a high speed, ultrasonic welding process. In the most commonly used process, ball bonding, fine diameter (average diameter is now < 25mm) gold or copper wire is welded to a thin (1mm) Al-1%Si-0.5%Cu bond pad on the semiconductor device. Typical bond pads are now less than 75mm square and devices like graphic processors may have more than 1000 on a single device. State-of-the-art bonders now operate at rates > 16 wires/second (32 welds with high speed motions between the two welds that define the ends of each wire). Placement accuracy must be better than ±2.5mm. It is not unusual for factories with well characterized and controlled materials and manufacturing to experience bond defect rates less than 10 ppm.
This half day workshop will cover:
- The Ball Bond Process: Step by Step Wire Bonding
- Welding
- The effect of ultrasonics on weld formation and materials properties
- Metallurgy and Intermetallics
- A comparison of the welds associated with Au-Al and Al-Cu bonding
- The effect of wire alloying on ultra-fine pitch reliability
- Wire properties, testing and chemistry
- Pull and shear testing wire bonds
- Understanding wire stiffness and the effect on looping
- Capillary design and selection for optimized processes
- Simple bond screening designed experiments
- How to optimize the bonding process
Biography
Lee is a consultant for Process Solutions Consulting where he provides process engineering consultation and SEM/EDS analysis. Lee’s previous experience includes 20 years as Principal and Staff Metallurgical Process Engineer at Kulicke & Soffa and Distinguished Member of the Technical Staff at Agere Systems. He has been awarded 4 patents, published more than 50 technical papers, and in 1999 won the John A. Wagnon Technical Achievement award from the International Microelectronics and Packaging Society (IMAPs). Major innovations include copper ball bonding, loop shapes for thin, small outline packages (TSOP and TSSOP, and CSPs) and introduction of DOE and statistical techniques for understanding semiconductor assembly processes. He is an IMAPs Fellow, V.P of the Keystone Chapter, and V.P Technology for IMAPS. In addition he is a senior member of IEEE.
Lee is a graduate of Lehigh University, Bethlehem, Pa where he earned a degree in Metallurgy and Materials Engineering.
PDC 2 -- Near Hermetic Packaging Concepts for Military and Medical Devices
Tom Green, Consultant
TJ Green Associates, LLC
TJ Green Associates LLC is a Veteran owned small business
www.tjgreenllc.com
This PDC is intended as an intermediate level course for process engineers, designers, quality engineers, and managers responsible for sealing, leak testing and RGA results and for those responsible for evaluating new polymeric cavity style packages.
Packages made from polymeric materials (e.g. LCP) as opposed to traditional hermetic seals (i.e. metals, glasses, ceramic etc) require a different approach from a hermeticity design and testing standpoint. The problem is now one of moisture diffusion through the bulk and package interfaces, which is different than water vapor permeating a crack in a glass to metal seal. A brief review of the techniques and methods to evaluate a "near-hermetic" approach is presented along with a discussion of the pitfalls and issues of TM 1014 (Seal) and TM 1018 (Internal Water Vapor) as applied to a “near hermetic package” along with the fundamental theory including: Fick’s law of moisture diffusion, WVTR, TGA and moisture diffusion coefficients. Applications of moisture sensing inside a package and a discussion on how to qualify a “near hermetic” package will be presented.
Biography
Mr. Thomas Green is an independent consultant and respected teacher. He has over twenty-seven years experience in the microelectronics industry and has worked at Lockheed Martin Astro Space and USAF Rome Laboratories. At Lockheed he was a Staff engineer responsible for the materials and manufacturing processes used in building custom high reliability space qualified microcircuits (Hybrids, MCMs and RF modules) for military and commercial communication satellites. Tom has demonstrated expertise in seam sealing and leak testing processes. He has conducted experiments and presented technical papers at NIST (National Institute Standards and Technology) and IMAPS (International Microelectronics and Packaging Society) on leak testing techniques and optimization of seam welding processes through statistical DOE methods. At USAF Rome Labs he worked as a senior reliability engineer and analyzed component failures from AF avionic equipment along with providing technical support for a variety of Mil specs and standards (e.g. MIL-PRF-38534 and MIL-STD-883). Tom is an active IMAPS member and Society Fellow. He teaches a full day industry course titled “Hermeticity and Near hermetic Packaging Concepts” at public conferences throughout the year and has worked as a hermeticity consultant for numerous military and aerospace companies. He has a B.S. in Materials Engineering for Lehigh University and a Masters from the University of Utah.
