High voltage thin film transistors integrated with MEMS

The integration of high voltage thin film transistors with a released MEMS process onto the same substrate is demonstrated. High voltage transistors capable of 800 V actuation voltage are used to actuate released metal cantilevers and membranes with a low temperature fabrication process (<350 °C) on glass substrates. This demonstration is an important step towards realizing MEMS arrays with integrated addressable drivers for applications which require high voltage, such as electrostatic MEMS devices on low temperature substrates (e.g. glass or flex). High voltage thin film transistors (HVTFT) provide the unique property of easily controlling high voltage (50–800 V) using a standard input voltage range (0–20 V). To our knowledge, this is the first demonstration of integrated HVTFT actuating released MEMS structures.