A semiconductor device includes a semiconductor wafer chip, a semiconductor device layer, and a reflectance reducing layer. The semiconductor wafer chip includes a device region and a peripheral region around the device region. The peripheral region includes a plurality of voids aligned along a side surface of the semiconductor wafer chip at a predetermined depth from a first surface of the semiconductor wafer chip. The semiconductor device element layer is on the first surface in the device region. The reflectance reducing layer is on the first surface of the semiconductor wafer chip in the peripheral region, that reduces a reflection of laser light incident from a second surface of the semiconductor wafer chip.