This paper reports on the optimization of 1 eV dilute nitride solar cells growth conditions. InGaAsN cells were grown by MBE under different conditions (V/III ratio, substrate temperature, surfactant) and were processed without post-growth annealing. Characterization results suggest that the V/III ratio should be kept above 10 and that using Bi as a surfactant does not improve the cell performances. Our best InGaAsN cells exhibit J sc and V oc values of 7.9 mA/cm 2 and 0.375 V respectively, under $\text{AM}0 > 870$ nm and without ARC.