Earth Day on April 22 isn’t just about environmental rallies and the mounds of trash in their wake. It’s also a reminder that there’s a lot of green to be made from green companies. The IBD 100 list of the very best stocks based on fundamental and technical factors includes several eco-friendly firms: 3. Aixtron (AIXG) The German company makes equipment used to make LED, or light-emitting diode, chips. LEDs are fast gaining steam as a green lighting alternative. They use far less power than incandescent bulbs without the mercury of fluorescents. LED chips are used in many different types...