Chemical deposition is a low-temperature technique compared with most other semiconductor film deposition methods. This has both advantages and disadvantages. An obvious advantage is the simple processing often inherent in a low-temperature technique. What may be a more important advantage, however, is that low-temperature deposition techniques usually (although not always) result in small crystal size. As recently as a decade ago, this would have been considered a decided disadvantage-large crystal size was almost always desired then, e.g., for photovoltaic cells in order to minimize grain boundary recombination. However, with the increasing emphasis on nanostructured materials over the past decade, this characteristic of CD films is now often considered an advantage.