Low noise RF MOSFETs on flexible plastic substrates

We report a low minimum noise figure (NFmin) of 1.1 dB and high associated gain (12 dB at 10 GHz) for 16 gate-finger 0.18-mu m RF MOSFETs, after thinning down the Si substrate to 30 mu m and mounting it on plastic. The device performance was improved by flexing the substrate to create stress, which produced a 25% enhancement of the saturation drain current and lowered NFmin to 0.92 dB at 10 GHz. These excellent results for mechanically strained RF MOSFETs on plastic compare well with 0.13-mu m node (L-g = 80 nm) devices.