Anton Kolbeck

Bond wire design for eXtreme Switch devices

Freescales third-generation eXtreme Switch devices set performance standards for automotive lighting. They are tailored to drive high-intensity discharge (HID) xenon, halogen and light-emitting diode (LED) lamps. For example, a halogen lamp draws high levels of current when first turned on, but much less once it has stabilized. The ICs therefor allow the lamps to draw high levels of current when needed at turn-on but less during operation. Hence, these devices have to withstand the event of an inrush current each time a lamp is switched on. Package and wire bond design have to consider the transient characteristics of Joule heating and heat transfer. The authors developed an approach for the current carrying analysis of bond wires in power packages. It is based on closed form solutions of the heat equation at single current pulse, repeated current pulses or arbitrary inrush current profiles. This paper focuses on the analysis of Joule heating in bond wires. We will solve the initial and boundary value problem for the Joule heating at an inrush current pulse. The solution will be validated with thermo-electric finite element simulation. We will then draw conclusions for the wire bond design.

High power multi-chip system integration in package

This paper presents a new high power package for automotive products. It provides innovative interconnecting concepts for multi-die integration of different semiconductor technologies in a single package with automotive grade reliability. Cost effective thermal performance and current carrying capabilities are improved compared to standard packaging methods. A description of key manufacturing process steps, the resulting package integrity, device performance and reliability will be given during the IEMT conference. Special focus will be on the optimization of the process with mold flow simulations and encapsulation experiments with a split flag design. Applied design and process development methodologies will be demonstrated for an automotive high power dual chip application. Experimental characterization will comprise thermal and electrical performance measurements and environmental stress tests.