Custom valve island prototyped in just 10 days

When semiconductor machine manufacturer STS required an ultra-compact valve island to drive actuators and control the flow of process gasses into its machines, global pneumatics expert Norgren created the perfect custom prototype in just 10 days.

STS is a leading manufacturer of specialist machines that are used in semiconductor manufacturing. The machines are used to etch away materials or deposit them onto silicon wafers that end up in devices such as MEMS (micro electromechanical systems) - an example of which would be a car airbag trigger.

Each machine employs three pneumatic valve islands. Because these machines are installed in semiconductor clean rooms, where floor space costs around 60 per square inch due to the ultra-clean conditions required, STS needed a valve island design that was as compact and reliable as possible. 

Key to securing the business was STS's confidence in Norgren's proven experience and capability with valve island technology. Rapid response to the customer's brief was also a critical factor. Norgren's design engineers at its UK Technical Centre in Lichfield rose to the challenge by offering a custom product that met STS's unique specifications.

Although a new product, the custom valve island was based on Norgren's tried and tested core competencies. The flow rate required from STS was low - just 30l/min. Off the shelf valve islands available from other pneumatics suppliers were all too large - offering flow rates of several hundred l/min, meaning that installing one of these valve islands would have wasted expensive clean room space. So Norgren designed a pilot valve with the smallest possible footprint, while maintaining visibility and access to critical functions such as LEDs and manual override. 

Because the required flow rate is so low, the valve is based on poppet technology, dramatically increasing reliability and life expectancy to around 100 million operations. Another key advantage of the low flow rate valve is that the solenoids need just 0.3W to operate, resulting in reduced heat build up within the machine.

Norgren's custom valve uses a body made from an advanced polymer, so it could be moulded to the exact specification required. For example, competing valves were such that the wiring and porting configuration was inconveniently located, meaning that the pipe work would have to have been re-routed within the machine and requiring additional pneumatic connectors and fittings. Norgren's custom valve was designed with a configuration that exactly matched STS's requirements, and being face mounted, it allows the pipes to enter straight into the valve island through the mounting panel, saving yet more space.

Says Ed Hinds, Engineering Team Leader at STS: "Norgren provided exactly what we needed when we needed it - a valve that's compact, inexpensive, and reliable. It's an effective solution to this challenging application."

Norgren