Novel analytical technique for on-line monitoring of trace heavy metals in corrosive chemicals

A novel analytical technique is presented in this paper for trace metal monitoring in corrosive chemicals. The technique is an application of anodic stripping voltammetry with an array of micro-machined mercury ultramicroelectrodes as the probe electrode. The latter is resistant to hydrofluoric acid and has been proven to be accurate, reproducible and robust. In a case study, the probe was continuously used in a HF bath for twelve hours with no sign of failure. It demonstrated the strong potential of this technique to perform real-time on-line monitoring of trace metals in corrosive chemicals such as those used in semiconductor processing.