Rudolph Technologies' inspection and metrology systems lead the way to better yields for chip makers. To create semiconductors, manufacturers deposit precise layers of conducting and insulating materials on silicon wafers. Rudolph's process control metrology equipment monitors these layers to ensure that the material doesn't get too thick or too thin. Its inspection equipment (around half of sales) looks for defects not obvious to the human eye, such as tiny scratches or gouges in the surface of a silicon wafer. The company also makes a range of data analysis and process control software. Rudolph gets about two-thirds of sales from customers outside the US.