Advanced Motion Control for Wire bonding
Featured Product from ETEL S.A.
This application note describes the LED/IC wire bonder ecosystem (market drivers, architectures, timings…) and focus specifically on the main technical challenges for the motion control part. The selection of the control architecture and its position encoders have a significant contribution on the total machine performance. Dedicated motion control solution from ETEL, as well as position encoders from HEIDENHAIN can greatly help wire bonder designers to face the new market requirements derived from chip miniaturization and its enhanced complexity.
Among the different equipment used in the semiconductor industry or mass production of Integrated Circuits (IC) and Light Emitting Diodes (LEDs), wire bonders are probably one of the most challenging in terms of motion control management. A first explanation relies on the fact that this technique is one of the oldest used in the semiconductor world with already many years of intensive optimizations (wire bonding was first reported in 1957). In addition, its short cycle times, complex looping trajectories and ultra-low impact forces (~30 grams) are calling for the most advanced control strategy. Today, market calls for continuous miniaturization and cost reduction in the whole IC assembly supply chain, which translates into smaller pad pitches, higher positioning accuracy for the tip, higher throughput and better impact control when the capillary tool tip contacts the pad or lead. Despite these complex challenges, the industry succeeded in offering good bond quality at increased bond rates (up to 20 wires/sec), maintaining wire bonding as the lowest-cost and the most reliable and flexible interconnection method. With more than 30’000 wire bonders sold every year worldwide, the market is nowadays extremely competitive, pushing the prices down to a level which may jeopardize OEM equipment makers to invest in R&D resources to work on machine redesign and motion control improvements.