Chemical beam epitaxy for photovoltaics and GaN-based electronics

随着环境和能源危机的迫在眉睫，高效太阳能电池和电动汽车等行业有望在不久的将来实现持续、壮观的增长。Yole Development预测，到2020年，电力设备的市场将强劲增长，达到200亿美元的水平。同样，绿色和平组织在一份综合报告中预测，到2050年，集中式太阳能电池将提供全球约25%的能源。然而，这些市场的最大限制因素是各自技术的生产成本。生产成本的很大一部分专门用于通过一种名为外延的技术制造基础材料，通过这种技术在晶体衬底上沉积非常高质量的薄膜。如果使用廉价的衬底材料，可以显著降低生产成本。硅片是实现这一目的的最佳选择。最近几年已经提出了几种方法，但没有一种方法将低生产成本与有效的残余热应力松弛结合起来。

With the impending environmental and energy crises, industries such as high efficiency solar cells and electrically powered vehicles are poised for sustained, spectacular growth for the near future. Yole developement is predicting strong market growth for power devices to a level of 20 billion dollars by 2020. Likewise, in a comprehensive report, Greenpeace is predicting that concentrated solar cells will supply about 25% of the world's energy by 2050. However, the biggest limiting factor for these markets is the production cost of their respective technologies. A significant part of the production costs is dedicated to the basic material fabrication by a technique called epitaxy, by which very high quality thin films are deposited on a crystalline substrate. The production costs can be decreased significantly if a cheap substrate material is used. Silicon is the best candidate for such a purpose. Several methods to that end have been proposed in recent years, but none is combining low production cost with effective residual thermal stress relaxation.