An image sensor may include a polydimethylsiloxane (PDMS) layer that is subwavelength, hydrophobic, and/or antireflective. The PDMS layer may be fabricated to include a surface having a plurality of nanostructures (e.g., an array of convex protuberances and/or an array of concave recesses). The nanostructures may be formed through the use of a porous anodic aluminum oxide (AAO) template that uses a plurality of nanopores to form the array of convex protuberances and/or the array of concave recesses. The nanostructures may each have a respective width that is less than the wavelength of incident light that is to be collected by the image sensor to increase light absorption by increasing the angle of incidence for which the image sensor is capable of collecting incident light. This may increase the quantum efficiency of the image sensor and may increase the sensitivity of the image sensor.