Colloidal Crystal (IMAGE) Purdue University Caption Researchers at Purdue have developed a "self-assembling" technique to create a "nearly perfect two-dimensional colloidal crystal," or a precisely ordered layer of particles, a critical step toward growing three-dimensional crystals for use in optical communications and other technologies. The method works by positioning tiny particles onto a silicon template containing precisely spaced holes that are about one-hundredth the width of a human hair. This photograph, taken with a scanning electron microscopy, shows a side-by-side comparison between Purdue's structure (right) and a structure that results when a template is not used. Credit You-Yeon Won and Jaehyun Hur, Purdue University School of Chemical Engineering Usage Restrictions None 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.