Photonic integration using Laser interference structured substrates

在单个衬底上集成不同的半导体材料对于未来的电子和光子器件是非常期望的。特别是，III-V族半导体在硅上的集成，工业衬底的选择，将利用现有的电子器件概念的好处，基于低成本，大的晶片尺寸和具有III-V材料具有上级电子和光子性能然而，由于晶体尺寸和其他性能的差异，材料集成多年来一直是一个挑战为了解决这个问题，我们提出了一种激进的方法，单片集成III-V族材料到硅衬底上使用创新的硅衬底纳米结构化工艺的基础上直接激光干涉。该方法将平面硅表面转化为高度结构化的阵列，该阵列可以适应晶体尺寸和类型之间的差异。这种新颖的方法有可能利用基于Si的平台上的III-V器件的单片集成的好处，这是下一代光子集成电路，III-V CMOS和量子器件的基本要求。该项目是高风险高回报的，基于对以前项目的偶然观察。一些原则证据已经存在，但总体方法尚待充分探讨。如果成功，这将最终解决高度失配外延的问题，并对行业产生变革性影响，打开在行业选择的衬底上集成广泛替代材料的前景。该提案旨在开发这种方法，以在硅上生产高质量的III-V缓冲层。在这些III-V层上，我们将生长，制造和测试光子器件，如激光和太阳能电池。激光器操作演示是CMOS芯片外光学互连的关键器件演示，可实现单个处理器之间的更快连接，并克服限制下一代计算性能的主要瓶颈。多结太阳能电池组合硅的吸收结和至少两个III-V结。半导体多结电池提供所有光致发光器件中最高的量子效率，有可能进一步超过50%。然而，目前的技术方法意味着这些电池对于消费者使用来说过于昂贵。我们相信，我们有潜力通过原位生产的结构化基板提供更低成本的方法，如果成功，将彻底改变太阳能发电。

The integration of diverse semiconductor materials on a single substrate is highly desirable for future electronic and photonic devices. In particular, the integration of III-V semiconductors on silicon, the industry substrate of choice, would leverage the benefits of existing electronic device concepts based on the low-cost, large wafer size and the excellent manufacturability of silicon with III-V materials offering superior electronic and photonic performance However materials integration has remained a challenge over many years due to dissimilarities in the crystal size and other properties which need to be accommodated at the interface of these materials without propagating into the III-V layer.To address this issue, we propose a radical method to monolithically integrate III-V materials onto silicon substrates using an innovative silicon substrate nanostructuring process based on direct laser interference. The approach transforms the planar silicon surface into a highly structured array which can accommodate the differences between crystal size and type. This novel approach has potential to leverage the benefits of the monolithic integration of III-V devices on a Si-based platform, which is an essential requirement for next-generation photonic integrated circuits, III-V CMOS, and quantum devices. The project is high risk-high reward, based on incidental observations from a previous project. Some proof of principle exists, but the overall approach is yet to be fully explored. If successful, this could finally solve the problem of highly mismatched epitaxy and have transformational impact on industry, opening the prospect of integration of a wide range of alternative materials on the substrate of industry choice. The proposal seeks to develop this approach to produce high quality III-V buffer layers onto silicon. On to these III-V layers we will grow, fabricate, and test photonic devices such as laser and solar cells. The demonstration of laser operation is a critical device demonstration for off-chip optical interconnects to CMOS enabling faster connection between individual processors and overcoming a major bottleneck which will limit next-generation computing performance. The multijunction solar cell combines absorbing junctions of silicon and at least two III-V junctions. Semiconductor multijunction cells offer the highest quantum efficiency of all photovoltaics, with potential to go further and exceed 50%. However, the current technology approach means that these cells are far too expensive for consumer use. We believe we have the potential to provide a lower cost approach through our in-situ produced structured substrates, which if successful could revolutionise solar energy generation.