Ultra-High Aspect Ratio InP Junctionless FinFETs by a Novel Wet Etching Method

Junctionless FinFETs with an array of ultra-high aspect ratio (HAR) fins, enabled by inverse metal-assisted chemical etching, are developed to achieve high on-current per fin. The novel device fabrication process eliminates dry etching-induced plasma damage, high energy ion implantation damage, and subsequent high-temperature annealing thermal budget, ensuring interface quality between the high-k gate dielectric and the HAR fin channel. Indium phosphide junctionless FinFETs, of record HAR (as high as 50: 1) fins, are demonstrated for the first time with excellent subthreshold slope (63 mV/dec) and ON/OFF ratio (3 x 10(5)).