Case History 4 -- Project: Burn off application in Semi-conductor manufacturing process furnace
Objective : Our client was facing extreme pressure from its customers because of high product failure rates. Improving product reliability was essential.
Challenges : The heaters our client had been using had a life expectancy of about 6 to 8 weeks. There were some extreme environmental conditions which contributed to failures.
The heaters our customer used had serpentine circuits where the wire pattern looks somewhat like a star pattern. With this design, the wire at the tips of the star pattern is not very well supported and it can sag and short against its lower neighbor causing element failure. Furthermore, these heaters utilized a quartz insulating tube which would frequently break in transit.
Solutions and their impact :
Farnam supplied an Inline Air heater which utilizes a high temperature ceramic honeycomb structure. This honeycomb structure supports the circuits much more effectively and holds them in place. The many cell walls each act as heat collectors and heat exchange surfaces. So, the heat exchange process is more efficient and the wire temperature doesn't become as extreme. Our client realized the following improvements.
- Better heat transfer and support subjected the circuits to far less stress and this increased heater life by a factor of 800% - 1000%.
- No heater failures in 15 months and very happy customers.
- Elimination of expensive quartz tube eliminated expensive breakage problem.
- Even though the largest savings was in reliability, we also lowered their product cost by 25% in addition to the quality savings.