GaN on patterned silicon (GPS) technique for fabrication of GaN-based MEMS

A method for fabricating suspended gallium nitride (GaN) structures for microelectromechanical systems (MEMS) without direct etching of GaN is demonstrated. The process combines a selective area growth of GaN on patterned silicon substrate (GPS) and a subsequent sacrificial wet etching of the silicon under the GaN structures. Both anisotropic and isotropic wet etching techniques are used to carry out the sacrificial etching. Experimental results show that the GPS-MEMS technique can be used to batch-fabricate various GaN-based MEMS devices with common silicon micromachining equipment.