During the production process, a wafer has to go through several temperature stages, which must be regulated in order to avoid wasting the expensive material.This involves much data and complex calculations, and therefore a PC-based solution is chosen. With an analog PC board the values of 32 pyrometers (0 to 10 V) are to be acquired with an acquisition cycle of 1 ms. For regulating the heating lamps, an algorithm is executed on the FPGA of the PC board. Analog and digital outputs are used for controlling and regulating the heating lamps.
For the measurement and regulation of the temperature the analog I/O board APCI-3120 for the PCI-bus was chosen. It satisfies all requirements: speed, precision, FPGA technology and long-term availability. Due to its various protective circuits it is suitable for the use in an environment with interferences.