Researchers at the Semiconductors Component group at the University of Twente's MESA+ Institute for Nanotechnology have created a microchip which directly integrated photovoltaic cells to generate its own energy:
What sets this device apart from is that high-efficiency solar cells are placed straight onto the electronics, producing self-sufficient, low-power devices which are highly suitable for industrial serial production and can even operate indoors.
The autonomous microsystem was developed by the Semiconductor Components group at the University of Twente's MESA+ Institute for Nanotechnology led by Professor Jurriaan Schmitz. The researchers collaborated with colleagues from Nankai University in Tianjin, China and the Debye Institute of Utrecht University. The research was made possible by the STW Technology Foundation.
Instead of manufacturing the solar cell separately, the design sees the chip used as a base and the solar cell applied to it layer by layer. According to the UT release, this results in a more efficient production process, uses fewer materials and ultimately performs better.