Embodiments relate to an image sensor that may include transistors, a first dielectric, a crystalline semiconductor layer on and/or over the first dielectric, a photodiode, a dummy region, via contacts, and a second dielectric. A photodiode may be formed by implanting impurity ions into a crystalline semiconductor layer to correspond the pixel region. A dummy region may be formed in the crystalline semiconductor layer excepting a region for the photodiode. Via contacts may penetrate the dummy region, and may be connected to the first metal interconnections. A second dielectric may include a plurality of second metal interconnections on and/or over the crystalline semiconductor layer. The plurality of second metal interconnections may electrically connect the via contacts to the photodiode.