Comparison of isotropic dry etching process using XeF2 and ANisotropic Wet Etching Process using EDP for microhotplate device

This paper discusses the difference between isotropic dry etching process using XeF₂ and anisotropic wet etching process using Ethyl Diamine Pyrocathecol (EDP). The process is a bulk-etch process necessary for obtaining a suspended structure in a microhotplate device. For the dry etching process using XeF2, the pressure of the nitrogen gas is fixed to 0 Torr, while the pressure of XeF₂ is fixed to 2.5Torr. Wet etching process using EDP is conducted in a fume cupboard with 75 ml ethylene diamine, 12 g pyrocathecol, and 10 ml water. Results show that both of these processes are suitable for a microhotplate device. However, there are some differences between the wet and dry etching processes that have to be considered when etching a microhotplate device. The differences in terms of surface condition, time to obtain the suspended structure, and etch rate for each etching process are discussed in detail in this paper.