In this communication, we have designed, simulated, performance improved, fabricated and characterized a shunt capacitive RF MEMS switch with perforated serpentine membrane (Au). Fabrication is done using surface micromachining with four masks. AlN dielectric material of 50 nm thickness is offering high isolation of − 58.5 dB at 31.5 GHz, and incorporation of perforation to the membrane the switch insertion loss is very low i.e., − 0.4 dB. The perforated serpentine membrane with non-uniform meanders of 500 nm thickness using Au material is helped to reduce the actuation voltage, the fabricated switch is requiring 4.5 V actuation voltage. DC sputtering PVD is used to deposit metal (Au) and dielectric (AlN) thin Films. S1813 photoresist is used as a sacrificial layer and the membrane structure is released using piranha, IPA and critical point drying (Pressure 1260 Psi, Temperature 31 °C).