Deep reactive-ion etching (DRIE) is a newly developed technique for high aspect-ratio etching applications such as creating deep penetration, steep-sided holes and trenches in wafers/substrates, which requires smooth side wall at high etching rate. The PlasmaPro System can satisfy this requirement because its unique design makes it possible to run both Bosch™ and Cryo etch technologies in the same chamber. Bosch™ process provides high etch rate while Cryo etch technique ensures the smooth side wall.