This month we feature an article on increasing stepper/scanner productivity by Steve Brainerd, a Senior Applications Engineer at Simax Lithography

 Stepper/Scanner productivity improvement

In today’s extremely competitive environment, semiconductor manufacturers are tested to maximize manufacturing equipment productivity. The ultimate goal is to use the equipment to produce profitable products 100% of the time without interruptions. Unfortunately, the state of semiconductor equipment at this time does require routine maintenance and checks to avoid potential catastrophic failures. The reduction in the non-productive time required for these routine checks is very important to achieving a profitable bottom-line.

Typically the photolithography process requires checks for focus, CDs, overlay, focus spots, framing blade setting, and the photoresist coating process. Each of these parameters need to be very tightly controlled to ensure maximum product yields. The time required for these checks can be over an hour with the risk of “bad” product being run. Typically these checks require the exposure, development, and metrology management of multiple wafers. This increases the complexity and potential risk of incorrect parameter analysis and mis-processing resulting in unnecessary equipment downtime.

Simax Application Engineering has developed a very efficient photolithography process monitor. This new improved monitor wafer combines all the photolithography process monitors on a single wafer. This significantly reduces the complexity and reduces the non-productive equipment time required to process the wafers. All metrology can be done off line, while the equipment continues to run product. Greater than 5% increase in equipment availability can be achieved with this technique.

Source: HP

For assistance in developing a custom monitor wafer for your process, please contact Simax Applications Engineering at simaxlithography.com