Wafer Alignment

Many steps in semiconductor development and manufacturing require high-precision alignment of a processing or testing device with respect to wafer. This can be a mask in a photolithography process, a substrate with micro LED arrays for micro display assembly, or a probe card for wafer testing.
SmarAct offers different motion and metrology systems that are optimized for the individual alignment task. The example shows a system with a 300mm wafer which is moved in XYR by SmarSHIFT electromagnetic direct drive stages while a TRIPOD aligns a probe card vertically with respect to the slope of the wafer. The approach is supported by three tactile sensors inside the TRIPOD, which are used for closed-loop force control. In addition, the design of the TRIPOD is ultra-flat such that microscopes with different working distances can be moved over the point of interest with the help of a SmarSHIFT gantry stage.