Three-Dimensionarlly Stacked Optoelectronic System-on-Chip Fabricated Using Grapho-Assembly

本文研究了实现三维堆叠的光电片上系统（SOC）的关键技术，重点研究了实现高精度三维堆叠的新型石墨组装技术和新型三维硅光子技术。我们在硅片的上下表面形成微/纳米尺度的凹凸图案，然后利用石墨烯组装中液体的表面张力将这些芯片精确排列。利用光电组件实现了小于0.1um的高对准精度。我们开发了TSPV （Through Si Photonic Via）和UDOC（单向光耦合器）新技术。我们成功地制作了直径为10um的TSPV，具有良好的光学约束。提出并制作了一种带侧镜的新型光栅耦合器。我们证实了通过TSPV传播的垂直光信号通过该光栅耦合器耦合到水平硅纳米光波导上，耦合效率高达80%以上。

Key technologies to achieve a 3D-stacked optoelectronic system-on-a chip (SOC) have been studied focusing on new grapho-assembly technology to achieve 3D stacking with high alignment accuracy and new 3D silicon photonics. We formed micro/nano-scale concavo-convex patterns on both upper and lower silicon chip surfaces and then these chips were precisely aligned making use of surface tension of liquid in the gapho-assembly. A high alignment accuracy of less than 0.1um has been achieved using the gapho-assembly. We have developed new technologies of TSPV (Through Si Photonic Via) and UDOC (Uni-Directional Optical Coupler). We successfully fabricated TSPV with a diameter of 10um showing excellent optical confinement. We proposed and fabricated a new optical grating coupler with side mirror. We confirmed that vertical optical signal propagated through TSPV was coupled to horizontal Si nano optical waveguide using this optical grating coupler with high coupling efficiency of more than 80%.