Selective-area metal-organic vapor phase epitaxy for monolithically-integrated semiconductor photonic circuits

1.利用椭圆偏振光谱法对金属有机物气相外延（MOVPE）生长过程进行了原位监测，并证明了椭圆偏振光谱法对MOVPE生长表面状态的监测能力。应用这些观察结果，我们制作了具有1 ~ 3个分子层的InGaAs/InP量子威尔斯阱，并用CTR方法对它们进行了表征。从CTR表征的信号被发现是上级的任何以前的报告，从而我们证实，他们的界面是真正的单层膜。生长速率和薄膜质量的纵向分析及其在生长条件优化中的应用我们通过制备特殊的基座，实验研究了InP和GaAs MOVPE中生长速率和薄膜质量沿着前驱物流动方向的纵向分布，并与我们新开发的生长模拟器进行了比较。根据实验结果，我们详细阐述了高温下表面粗糙度的形成机理， 关于我们 合理确定了生长条件，避免了可能出现的表面粗糙度.金属有机物气相扩散增强选择区外延技术的发展作为单片光子集成电路中的一种有源/无源集成技术，我们提出并发展了金属有机物气相扩散增强选择区外延技术（MOVE）。通过利用这种技术，我们可以实现有源区和无源区之间的带隙差在1.55 μ m，大到200 nm的块体材料（由于成分的变化），和大到500 nm的量子威尔斯（由于成分和厚度的变化）。这些数字远远大于传统的数字。选择区MOVPE的模拟为了统一理解MOVPE中的选择区生长，我们开发了一个通用的模拟器。利用一个能独立考虑横向蒸气扩散和横向表面迁移影响的二维模型，我们可以成功地解释实验结果。结果表明，在传统选区生长中，表面迁移通道占主导地位，而在MOVE中，横向气相扩散通道占主导地位. MOVE是世界上唯一能够形成波导阵列的选择性区域生长技术。利用这一特性，我们首次成功地用选区外延法制作了1 × 2 MMI耦合器。此外，利用有源/无源集成能力，我们首次制作了一个用于光交换的光放大器门开关电路，并证实了它的工作。少

1. In-situ monitoring of MOVPE by spectroscopic ellipsometryWe here tried in-situ monitoring of metal-organic vapor phase epitaxy (MOVPE) by spectroscopic ellipsometry, and showed its ability to observe growth surface state. Applying the results of the observation, we made InGaAs/InP quantum wells having 1 to 3 molecular layers, and characterized them using CTR method. The signals from the CTR characterization were found to be superior to any previous reports, thereby we confirmed that their interfaces were truly monolayer abrupt.2. Longitudinal analysis of growth rate and film quality and Its application to growth condition optimizationWe experimentally investigated longitudinal distribution of growth rate and film quality along the direction of precursor flow in InP and GaAs MOVPE by preparing a special susceptor, and compared the results with our newly developed growth simulator. Based on the results, we specified the mechanism of surface roughness formation at high temperatures, an … More d made logical determination of growth conditions for avoiding the surface roughness possible.3. Development of metal-organic vapor-phase-diffusion-enhanced selective-area epitaxyAs an active/passive integration technology in monolithic photonic integrated circuits, we proposed and developed metal-organic vapor-phase-diffusion-enhanced selective-area epitaxy (MOVE). By utilizing this technique, we could achieve band gap difference between active and passive regions at 1.55mum as large as 200nm in bulk material (due to composition variation), and as large as 500nm in quantum wells (due to composition and thickness variation). These numbers are by far larger than conventional ones.4. Simulation of selective-area MOVPEFor the purpose of understanding selective-area growth in MOVPE in a unified manner, we developed a universal simulator. By utilizing a two dimensional model that could take the effects of lateral vapor diffusion and lateral surface migration independently into account, we could explain the experimental results successfully. It was shown that, in the conventional selective-area growth, the surface migration channel was dominant whereas, in the MOVE, the lateral vapor diffusion channel was dominant.5. First fabrication of photonic devices and integrated circuits by MOVEThe MOVE is the only selective-area growth technology in the world which is able to form waveguide arrays. By applying this feature, we succeeded in fabricating 1x2 MMI couplers by selective-area epitaxy for the first time. Furthermore, by utilizing active/passive integration capability, we fabricated an optical amplifier gate switch circuit for photonic switching for the first time, and confirmed its operation. Less