HORIBA Instruments, Inc. Optical Fiber Type Hot Phosphoric Acid Concentration Monitor CS-620F

In 3D NAND manufacturing process, dozens of layers of SiO2 and SiN are deposited, and the SiN layer is selectively removed using hot phos. In this process, the desired etching rate can be achieved by controlling the concentration and temperature of the chemical solution. Previous products have difficulty to measure high temperature chemicals, but the CS-620F is able to measure at high temperatures  up to 170 C degrees.  Continuous Measurements are made using absorption spectroscopy, which requires less maintenance and fewer consumables versus other methods.