Fabrication of InP-based freestanding microstructures by selective surface micromachining

InP-based microstructuring methods are presented with a view to develop micro opto electro mechanical systems (MOEMS). Fabrication parameters and dimensions of the freestanding structures are determined for specific technological constraints (etching selectivities, anisotropy, sticking phenomena). 1 mu m thick InGaAs deformable cantilevers, bridges and membranes have been fabricated by elimination of around 2 mu m-thick InAlAs sacrificial layers. Showing high aspect ratio, smooth surfaces and high accuracy in thicknesses, these microstructures are perfectly suitable for optical applications.