How does the FastGate® measurement work?
The FastGate metrology system is based on the principle of elastic deformation. Many materials can be deformed to a limited extent (below their elastic limit) and they will spring back. A perfect example would be to press a rubber ball against a desktop. Note how the ball (probe) deforms and makes an intimate disk shaped contact with the flat desk (wafer). When you release it, the ball elastically returns to its original spherical shape. Neither surface is damaged. We precisely control the force and the motions to create a reproducible contact.
