Development of the one step DRIE dry process for unconstrained fabrication of released MEMS devices

Current technologies allow the manufacture of released devices using deep reactive ion etching (DRIE) and SOI wafers, provided the device movement is not required to be more than a few microns (1-10 mum) Here, we describe the 'waffle technique', which will allow large areas surrounding a device to be cleared, therefore opening up opportunities for the design of devices with large movement capabilities (limited by the device's own actuation) or large volume reservoirs for micro fluidic applications. It should be noted that all DRIE etching in this work was carried out using a Surface Technology Systems DRIE which uses a process developed from the Bosch process (R B Bosch Gmbh 1994 US Patent Specification 4855017 and German Patent Specification 4241045CI) termed 'time multiplexed deep etching' (TMDE).