Nanopillar Array Diagram (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption An aluminum substrate forms a template for a forest of cadmium sulfide nanopillars and also serves as a bottom electrode. Embedded in clear cadmium telluride and equipped with a top electrode of copper and gold, the result is an inexpensive and efficient 3-D solar cell. Credit Lawrence Berkeley National Laboratory Usage Restrictions with credit as given License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.