Microfluidics technology holds great promise for designing state-of-the-art culture chips due to its ability to incorporate the nanoliter liquid transport. We employed soft lithography to reproducibly replicate the structure of the ommatidium with nanoscale fidelity. MCF-7 cells cultured in these chips, occupy individual concave wells, which augment the capability of the chip for cell growth and single-cell analyses and generation of tumor-like structures.