MKS Instruments Inc. has introduced the GLM-2000 PV and silicon wafer monitor for quality control in photovoltaic and crystalline silicon wafer processing for solar applications. The multi-function GLM-2000 uses a high-speed non-contact radio-frequency detection technology to measure photoconductance in PV and silicon feedstocks and partially processed cells, either in-process or post-process.
The GLM-2000 metrology tool employs a novel implementation of the current RFPCD measurement technique to instantaneously measure sheet resistance, minority carrier lifetime, photoconductance decay and photoconductance rise – key quality-control parameters for PV processing, the company says.
The GLM-2000 employs a programmable LED array that permits measurements at different light intensities, allowing the user to determine the true steady-state minority carrier lifetimes. The use of LEDs also allows flexibility in the choice of light color, which the company says can be useful in distinguishing surface effects from bulk characteristics.