New Additions to the WaferSense® & ReticleSense® Portfolio in Development – Including Humidity Measurement
Q&A with Allyn Jackson, Field Applications Engineer
Q: Among other sensors, CyberOptics currently markets both WaferSense® leveling and vibration sensors. What led to the development efforts behind the combined Automated Multi Sensor (AMS) measurement device?
A: Customers want the convenience of one device that combines the best of both measurement technologies. Plus, the sensor is lightweight and thinner at ½ the thickness of the other individual leveling or vibration devices so it can travel to all chambers of the tools.
The technology will also be incorporated into smaller wafer sizes including the 150mm and will be available in the reticle quartz form factor so it can easily move through the photolithography tools.
We continue to evolve our proprietary technology to address customer needs. The new WaferSense® and ReticleSense® Automated Multi Sensor (AMS) line is planned to be available soon and with an official launch at Semicon West in July.
Q: In the semiconductor manufacturing environment, tell us about the importance of measuring humidity?
A: Working with our customers, we have learned that there are concerns when they get to finer line width. They want to control the amount of oxidization on the wafer and drive down to low humidity in their local area of the fab. When plunging very dry gas into the Foups it’s important to keep the wafer in low humidity.
There are other customers that want higher humidity so they don’t have electro-static discharge (ESD) issues with the wafers. So, measuring humidity is a key application of interest for these process and equipment engineers.
We’re designing and developing humidity measurement capabilities into our new proprietary WaferSense® and ReticleSense® Automated Multi Sensor (AMS) line so users can speed acceleration, vibration, inclination and humidity measurement with the all-in-one sensors. The ReticleSense AMS will have 1 humidity sensor and the WaferSense form factor will have 5 humidity sensors.
Q: Why multiple humidity sensors?
A: When these customers are plumbing dry gas into the foup while the wafers are inside, the dry gas has to uniformly rise. When the gas is flown in, it can vibrate the wafers, so it is important to measure the humidity uniformity. This AMS model has 1 humidity sensor in the center and 4 near the wafer edge.