In this work, a high-k In0.53Ga0.47As silicon-on-insulator FinFET (InGaAs–SOI–FinFET) is presented for high-switching and ultra-low power applications at 7 nm gate length. Indium Gallium Arsenide (InGaAs) is a compound semiconductor that has gained attention in the field of semiconductor devices, including FinFETs. The incorporation of InGaAs in proposed FinFETs introduces several advantages, making it an attractive material for certain applications. InGaAs–SOI–FinFET performance has been observed and found high electron mobility, improved On-Current performance (ION), drain current (IDS), transconductance (gm), energy bands, lower subthreshold swing (SS), electric field, surface potential, and better short-channel behaviour. All the results of InGaAs–SOI–FinFET have been simultaneously compared with SOI-FinFET and conventional FinFET (C-FinFET). Incorporating InGaAs in the channel with high-k gate material enhances the drain current by ⁓75% and ⁓77% in the proposed device compared to the other two counterparts. Owing to the higher drain current in the InGaAs–SOI–FinFET, other parameters have also been improved, which leads to higher performance applications.