Our proprietary surface charge profiler (SCP) provides fast, accurate and repeatable measurement of the electrical properties of silicon wafers. This patented, non-contact, non-destructive system utilizes the surface photo-voltage effect to provide precise measurement of wafer surface charge and simultaneous measurements of the near-surface recombination lifetime and wafer conductivity type. The system has the ability to measure doping concentration / resistivity of bulk crystalline Si (silicon) wafers, epitaxial films, and crystalline damage level of ion implanted Si wafers.

Our fully programmable robotic / measurement system moves wafers from cassette to an insolated wafer support / vacuum chuck mounted on theta and linear air bearing stages in the SCP measurement chamber. The non-contact probe is positioned directly over the wafer surface. Probe movement, wafer rotation and measurement location(s) are controlled by easily programmable software and are designed to function without the need of additional operator intervention.

The SCP probe projects a chopped column of light onto the wafer’s front surface and measures the resulting changes in electrical characteristics of the wafer through capacitive coupling. The high sensitivity of the method allows accurate determination of the near surface doping in crystalline / epi wafers and reliable monitoring of implant process parameters.