Superconducting MEMS were developed by IRAM for millimetre wave heterodyne receivers improvements. In this report, the characterization of these capacitive MEMS is presented (profilometry, vibrometry, X rays, electric and thermal). They were described with a simple analytical electromechanical model which can be easily implemented with an equivalent high frequency circuit in the COMSOL multiphysic software to take into account the superconductivity. This work answers to the question of what are the MEMS geometries well suited for broadband heterodyne receivers requirements.