可调谐垂直腔面发射激光器支撑结构优化设计  

Design Optimization of Mechanical Support Structures in Tunable Vertical Cavity Surface Emitting Lasers

作　　者：吕家纲 李伟[1] 戚宇轩 潘智鹏 仲莉[1] 刘素平[1] 马骁宇[1] LüJiagang;Li Wei;Qi Yuxuan;Pan Zhipeng;Zhong Li;Liu Suping;Ma Xiaoyu(National Engineering Research Center for Optoelectronic Devices,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;College of Materials Science and Opto-Electronic Technology,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院半导体研究所光电子器件国家工程研究中心,北京100083 [2]中国科学院大学材料科学与光电技术学院,北京100049

出　　处：《光学学报》2023年第1期173-180,共8页Acta Optica Sinica

基　　金：国家自然科学基金(62174154)。

摘　　要：基于微机电系统(MEMS)的850 nm可调谐垂直腔面发射激光器(VCSEL),设计了一种双曲线梁结构,以提升器件机械和调谐特性。通过分析传统等截面梁结构的受力情况,提出了双曲线结构优化设计,将梁结构端面的面积增大从而降低最大应力。理论仿真结果表明:优化后器件上反射镜的最大偏移量基本保持不变,支撑梁上下表面的最大应力分别降低了23.4%和17.0%,谐振频率增大了7.9%;当MEMS-VCSEL分别为半导体腔主导(SCD)结构和空气腔主导(ACD)结构时,波长调谐范围分别为16.6 nm和42 nm。该优化方式的优势在于不需要改变激光器的结构,同时可与其他优化方式兼容,具有一定的应用前景。Objective Vertical cavity surface emitting lasers(VCSELs) based on micro-electro-mechanical systems(MEMSs) are widely applied in optical communication, optical coherence tomography, and other fields, with the advantages of wide continuous tuning range, fast tuning rate, and low power consumption. The tuning modes of MEMS-VCSEL include electrostatic, piezoelectric and thermoelectric, but the basic principle is to control the mirror shift to change the overall cavity length of the resonant cavity to achieve wavelength tuning. The support structure of the suspended mirror will be subjected to alternating loads during tuning, and the stress concentration will occur at the fixed end position of the structure, leading to the fatigue fracture. The optimization design of the beam structure can improve the reliability of the device at a low cost, which is a high-feasibility optimization method. In this paper, the support beam structure of the suspended mirror is optimized on the micro/nano-scale, and the hyperbolic beam structure is proposed. The maximum stress is reduced, and the resonant frequency is improved without changing the maximum offset and the corresponding bias of the mirror in the MEMS structure. The proposed optimization method can improve the mechanical and tuning characteristics of the device without introducing additional process steps, which is well compatible with other materials and structure optimization methods.Methods A hyperbolic beam structure is designed for 850 nm tunable VCSEL based on MEMS to improve the mechanical and tuning characteristics. First, the Mises stress distribution of the traditional constant cross section(CCS)beam structure is analyzed by the finite-element method. The stress concentration problem will appear at the fixed end surfaces because the section modulus at different positions of the structure is the same with different moments when the CCS beam structure is subjected to uniform load. Then, the maximum stress on the structure can be reduced by increasing the geometry siz

关 键 词：激光器 垂直腔面发射激光器 可调谐激光器 微机电系统 机械特性 调谐特性 

分 类 号：TN365[电子电信—物理电子学]