Research On Coupling Characteristics Of Semiconductor Laser And Optical Silicon-Through-Via

In the information explosion today, data transmission is developing in the direction of large capacity, high speed and low loss. The traditional electric interconnection has been unable to meet the growing demand of users, which has led to the generation of optical communication technology. And with the development of integrated circuit, integration of the circuit is higher and higher, and the feature size of the transistor is also becoming smaller and smaller. They have been following the Moore's law in progress. But when the feature size of the transistor is reduced to the nanometer scale, it has almost reached the physical limit. We will have to start from other aspects to improve the circuit performance. Now that the three-dimensional(3D) integrated circuit is supposed to be the development direction of integrated circuit in the future. While through-silicon-via technology is the key to achieve a three-dimensional integrated circuit. At present, it is mainly transmitted electrical signals in the through-silicon-via. It can improve the performance of circuit, but also has its limitations. People pay their attention to the three-dimensional optical-electronic hybrid integrated circuit, which is the combination of the optical interconnection and the three-dimensional integrated circuit. Optical signals can be transmitted in the through-silicon-via. This article is based on it, studying the coupling characteristics of laser and optical through-silicon-via.Firstly, according to the similarity of the optical through-silicon-via and the optical waveguide, the optical through-silicon-via is analyzed by the correlation theory. And its mode field distribution is obtained. Then the mode field of semiconductor laser and through-silicon-via are approximated by the Gaussian mode field distribution, and the overlap integral in the fast and slow axis direction between them are calculated based on the mode coupling theory. So the formula of coupling efficiency is gotten. On the premise of Gaussian mode field distribution approximation, combined with the special properties of elliptic beam produced by semiconductor laser, the optical coupling theory of semiconductor laser and optical aperture is described from the perspective of mode field radius and phase match, and the influence of different propagation distance, lateral position deviation and angular deviation on the coupling efficiency is analyzed. What's more, the whole modeling and simulation are made by Rsoft software, which proves the correctness of the theoretical analysis. Finally, from the perspective of mode field matching, this paper puts forward two ways to increase the coupling efficiency. One is to change the structure of semiconductor laser, and the other is to join optical elements between the laser and optical through-silicon-via to change the coupling way.