We have fabricated luminescent (Er,Ho)₂O₃ thin films by atomic layer deposition (ALD) and studied their capability to enhance the performance of state-of-the-art single-junction c-Si bifacial solar cells. The films convert IR photons (e.g. 1523 nm) by threeand two-photon upconversion process to emit visible-light in the 400-700 nm range. When the films were coupled with solar cells, similar to 3% improvement in the short-circuit current density (620 +/- 5 to 638 +/- 5 mAcm^-2) was recorded under a simulated solar excitation equivalent to 16 suns. These findings highlight a potential of ALD for the design and fabrication of luminescent coatings for practical solar cell devices.