Effimax Solar Inc, spun out from the University of Illinois in Champaign-Urbana, is dedicated to reducing solar manufacturing costs and facilitating affordable solar power at the consumer level. To achieve this, Effimax has developed a nanotexturing approach called Simultaneous Plasma Enhanced Reactive Ion Synthesis and Etching (SPERISE). This technique uses a common reactive ion etcher to create high density, high aspect-ratio nanocone array on the entire silicon surface. The texturized silicon solar cells have a light reflection of only ~1% in both wafer and thin film, and light transmission of only ~4% in thin film in a broad band, meaning there is 95% sunlight absorption. This absorption enhancement property is independent of light incent angle, creating omnidirectional absorbers that maintain the same efficiency regardless of the time of day.
