This work analyzes and optimizes the design with emphasis on the inversion charge characteristics for InGaAs negative-capacitance FinFETs (NC-FinFETs) by using theoretical calculation corroborated with numerical simulation. Our study indicates that, optimized ferroelectric remnant-polarization (Pr) for InGaAs devices can be chosen by the capacitance matching at the optimized sub-band of the inversion capacitance. In addition, the optimized sub-band is different for the InGaAs devices with different fin-width. The Pr optimization of the InGaAs device is also different from the Si device. After the optimization, the quantum-capacitance induced inversion charge loss for InGaAs devices can be mitigated from ∼2.4X to ∼1.1X due to the action of negative capacitance.