Laser-Engineered Silicon: Manufacturing Low Cost Photonic Systems

硅光子学有望通过允许具有最佳光学和电子功能的材料的组件的密集集成来彻底改变现代光电子学。近年来，这一领域取得了很大进展，许多硅光子器件现在已经达到（或超过）最先进系统的性能要求。这包括超低损耗互连以及高速光再生器、放大器、调制器和探测器，它们构成了光子电路的基石。然而，到目前为止，大部分进展都是在具有厚埋氧化层的绝缘体上硅（SOI）平台上取得的，这在很大程度上与电子设备开发不兼容，而且相对昂贵，因此阻碍了真正的集成系统进入大批量市场。因此，在SOI光子学的性能优势超过成本和设计限制之前，仍然有关键的挑战需要克服，为考虑替代平台敞开大门。在这个项目中，我们建议开发一种低成本和低温激光材料加工工艺，以制造高质量的多晶半导体光子平台，其性能将与SOI同行相媲美。激光加工的多晶材料已经在电子技术中得到了很好的应用，在电子技术中，为了降低加工成本，可以牺牲一些性能，例如，在智能手机和电视的背板中。然而，如果多晶颗粒可以长得和单个组件一样大，那么光学（和电子）性能将接近单晶材料。本研究以电子学社群所建立的平台为基础，寻求培育大晶粒多晶材料，以实现低损耗光子元件。重要的是，这种激光结晶过程的高度本地化直接缓解了与多材料和多层光子器件集成相关的问题，并且还可以用于在制造后期修改或修复单个组件，有助于提高产量并降低集成系统的成本。此外，这种方法提供了独特的优势，消除了半导体光子学对衬底的依赖，从而提供了通过使用具有增强光学功能、增加透明度甚至柔性塑料的衬底材料来扩展应用空间的可能性。通过降低与设备制造相关的成本和障碍，我们的创新项目将为在主流光电系统中广泛使用激光工程半导体光子元件奠定基础。

Silicon photonics promises to revolutionize modern optoelectronics by allowing for dense integration of components that feature the best optical and electronic functions of the material. In recent years great progress has been made in this area, with many silicon photonic devices now meeting (or exceeding) the performance requirements of state-of-the-art systems. This includes ultra-low loss interconnects as well as high speed optical regenerators, amplifiers, modulators, and detectors, which form the building blocks for photonic circuits. However, to date, much of this progress has been achieved on silicon-on-insulator (SOI) platforms with a thick buried oxide layer, which are largely incompatible with electronic device development, and relatively expensive, thus precluding truly integrated systems from reaching the high-volume market. Consequently, there are still crucial challenges to overcome before the performance benefits of SOI photonics outweigh the costs and design constraints, leaving the door open for alternative platforms to be considered. In this programme we propose to develop a low cost and low temperature laser materials processing procedure to fabricate high quality polycrystalline semiconductor photonic platforms that will rival the performance of their SOI counterparts. Laser processed polycrystalline materials are already well-established for use in electronic technologies where some performance can be sacrificed in favour of reduced processing costs, for example, in the backplanes of smart phones and televisions. However, if the polycrystalline grains can be grown as large as the individual components, then the optical (and electronic) properties will approach those of the single crystal materials. By building on the platform established by the electronics community, this work seeks to grow large grain polycrystalline materials to realize low loss photonic components. Importantly, the high localization of this laser crystallization procedure directly alleviates issues associated with multi-material and multi-layer photonic device integration, and can also be used to modify or repair the individual components at a late stage in the fabrication, helping to increase the production yield and reduce the costs of integrated systems. Furthermore, this method offers the unique advantage of removing the substrate dependence from semiconductor photonics, thus offering the possibility to extend the application space through the use of substrate materials with enhanced optical functionality, increased transparencies, or even flexible plastics. By reducing costs and barriers associated with device fabrication, our innovative project will set the scene for wide spread use of laser-engineered semiconductor photonic components in mainstream optoelectronic systems.