Blue-violet optical pulses of 9-kW peak power and 150-fs duration were obtained from a GaInN master oscillator power amplifier system using a nonlinear dispersion compensator. Seed pulses from a dispersion-compensated GaInN mode-locked semiconductor laser diode were stretched to 3-ps duration using a nonlinear dispersion compensator with a spatial light modulator that added second-order phase dispersion to an optimized nonlinear phase dispersion compensating the higher-order dispersion of the optical pulses. The stretched phase-optimized pulses were efficiently amplified to 3.0 nJ by a GaInN semiconductor optical amplifier. The amplified pulses were subsequently compressed using a linear pulse compressor, yielding 1.4-nJ femtosecond pulses. The obtained results show the highest peak-power ever reported for an electrically-pumped semiconductor gain medium.