Selective Area Growth of Semiconductor Structures by MOCVD for Telecommunication Applications

光子集成电路(PIC)承诺降低成本并提高关键组件和系统的性能，使光通信网络成为我们现代电信系统的主干。就像集成电路对电子产品所做的那样，PIC通过减少制造步骤的数量、提高成品率并通过批量制造实现规模经济来降低成本。光子集成一般有两种方法：混合集成，其中器件分别制造和组装，以及单片集成，其中所有器件都在单个芯片上制造在一起。在混合集成中，复合器件得到了很好的优化；然而，由于需要对准亚微米级的器件，以及随之而来的严重的可靠性问题，器件的集成令人望而生畏，而且成本高昂。光子电路的单片集成从设计上解决了封装问题，但由于要集成的器件种类繁多，并且针对每个器件分别优化了不同的材料系统，因此单片集成比电子电路复杂得多。特别是，现代PIC需要工作在不同波长的组件，以便通过波分复用(WDM)利用光纤提供的巨大带宽。在单个芯片上制造不同波长激光器的一种巧妙方法是选择性区域生长(SAG)，通过改变掩蔽层的尺寸可以仔细地控制由金属有机化学气相沉积(MOCVD)生长的外延III-V半导体层的成分和厚度。因此，可以在一个芯片上同时生长多个波长的激光器。在这个项目中，我们将使用麦克马斯特大学的MOCVD开发新的SAG工艺，为Artic Photonics目前使用的光子集成平台提供单生长多波长激光结构。

Photonic integrated circuits (PICs) promise to drive down the cost and increase the performance of the vital components and systems that enable the optical communications network, which forms the backbone of our modern telecommunications system. Just as the integrated circuit did for electronics, PICs reduce the cost by reducing the number of fabrication steps, improving yield and enabling economies of scale through batch fabrication. There are two general approaches to photonic integration; hybrid integration, where devices are separately fabricated and assembled, and monolithic integration, where all devices are fabricated together on a single chip. In hybrid integration, the composite devices are well-optimized; however, the integration of devices is daunting and expensive, due to the need for alignment of devices on a sub-micron scale, and the serious reliability issues that ensue. Monolithic integration for photonic circuits solves the packaging problem by design, but is far more complex than for electronic circuits due to the wide variety of devices to be integrated and the different materials systems that are separately optimized for each device. In particular, modern PICs require components that operate at different wavelengths in order to take advantage of the vast bandwidth afforded by optical fibers, through wavelength division multiplexing (WDM). An elegant approach to fabricating different wavelength lasers on a single chip is selective area growth (SAG), where the composition and thickness of epitaxial III-V semiconductor layers grown by metallo-organic chemical vapor deposition (MOCVD) can be carefully controlled by varying the dimensions of a masking layer. As a result, multiple wavelength lasers can be grown simultaneously on a single chip. In this project, we will develop new SAG processes using the MOCVD at McMaster University to provide single-growth multi-wavelength laser structures to the current photonic integration platform in use by ArtIC Photonics.