Improving material logistics via automation in an existing semiconductor fab

The introduction of a new product or technology into an existing semiconductor fab involves a combination of new processes, material flows and equipment sets. These changes may introduce manufacturing inefficiencies for both existing production and the new product sets, making it more challenging over time to compete with dedicated facilities specifically designed to optimize production of the new technologies. Yet it is necessary to effectively utilize a fab over multiple generations to attain a return on the large investments associated with semiconductor fabs. This paper presents an overview of the implementation of an automated material handling system (AMHS) designed to enhance the competitiveness of a mature 200 mm manufacturing facility. The fab had experienced a number of product and technology introductions over time, and the cumulative layout and flow changes were affecting performance metrics including cycle times, equipment utilization and labor efficiency. The implementation of a large scale AMHS into a high volume manufacturing environment involves many challenges including physical constraints such as ceiling height, floor space, right-of-way and cleanliness limitations; logistical implications associated with executing a project that spans the entire facility while minimizing disruption to production; and the requirement to provide seamless integration into existing legacy systems along with a familiar 'look and feel' interface to existing operations. The paper also describes issues associated with the integration of AMHS equipment from multiple suppliers. The resultant system is one of the largest automated interbay systems in the world in terms of volumes, size, scope and complexity, transporting material in a timely and cost-effective manner. The automation solution has enhanced the ability of the fab to support multiple generations of process and product flows, improved operator efficiency, and provided faster and more predictable delivery times between production areas.