This paper demonstrates the use of conductivity sensors to monitor and control the concentration of HF etching solutions. Effects of etch byproducts on the conductivity measurements have been investigated. Once the etch byproducts are characterized and accounted for, results showed that a much more stable etch process can be obtained and the bath life can be extended even in the presence of etch by products.
Archive for tag: HF
As electronic devices are evolving to more diversified and specifically function-oriented applications, silicon-based semiconductors have shown their limitation to unprecedented functionality requirements such as high power, high frequency, and high temperature operation. Growing utilization of IV-IV compounds (e.g. SiGe, SiC), III-V compounds (e.g. GaAs, GaN) as well as hetero-epitaxial structures with Si has become an inevitable trend.