高成品率大耦合因子DFB激光二极管芯片设计与制备  

Design and Fabrication of High Yield and High Coupling Factor DFB Laser Diode Chips

作　　者：姚文港 郝腾 张坤伟 刘婷婷 Yao Wengang;Hao Teng;Zhang Kunwei;Liu Tingting(The 13th Research Institute,CETC,Shijiazhuang 050051,China)

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051

出　　处：《微纳电子技术》2024年第6期38-44,共7页Micronanoelectronic Technology

摘　　要：设计并制备了一种基于相移光栅的大耦合因子分布反馈(DFB)激光二极管芯片,解释了相移光栅在大耦合因子下实现芯片高成品率的机理。采用传输矩阵法模拟了不同耦合因子下随机相位对均匀光栅和相移光栅激光二极管芯片单模特性的影响,发现对于常规均匀光栅DFB结构,随着耦合因子的增加,芯片阈值增益差会明显降低,从而降低芯片单模成品率;而相移光栅DFB结构在不同耦合因子下,芯片阈值增益差并没有明显变化,仍能够保证比较高的单模成品率。采用电子束光刻制作了1/4波长相移光栅和均匀光栅并进行了对比,最后制备出大归一化耦合因子(κL=2.1)的相移光栅DFB激光器二极管芯片。测试统计数据显示,与均匀光栅激光二极管芯片相比,新型相移光栅DFB激光二极管芯片成品率明显高,达70%以上。与常规归一化耦合因子(κL≈1.2)DFB激光二极管芯片相比,在宽温(-40~95℃)下,新型大耦合因子激光二极管芯片的光谱单模特性更稳定,同时具有更低的阈值电流,在低工作电流(30 mA)下,芯片的-3 dB带宽大于18 GHz,满足传输速率为25 Gbit/s的高速传输协议要求。A large coupling factor distributed feedback(DFB)laser diode chip based on phaseshifted gratings was designed and fabricated,and the mechanism by which phase-shifted gratings achieving high yield of chips with large coupling factors was explained.The influence of random phase on the single-mode characteristics of uniform grating and phase-shifted grating laser diode chips under different coupling factors was simulated using the transfer matrix method.It is found that for conventional uniform grating DFB structures,the threshold gain difference of the chip would significantly decrease with the increase of coupling factor,thereby reducing the singlemode yield of the chip.However,under different coupling factors,the threshold gain difference of the chip with the phase-shifted grating DFB structure does not change significantly,which can still ensure a relatively high single-mode yield.1/4 wavelength phase-shifted grating and uniform grating were prepared by using electron beam lithography for comparison,and finally a high normalized coupling factor(κL=2.1)phase-shifted grating DFB laser diode chip was fabricated.Test statistics show that compared to uniform grating laser diode chips,the single-mode yield of the new phase-shifted grating DFB laser diode chip is significantly higher,with a yield of over 70%.Compared to conventional normalized coupling factor(κL≈1.2)DFB laser diode chips,the new large coupling factor laser diode chip exhibits more stable single-mode spectral characteristics in a wide temperature range(-40-95℃).At the same time,the chip has a lower threshold current and a-3 dB bandwidth of greater than 18 GHz at low operating current(30 mA),which meets the requirements of high-speed transmission protocol with a transmission rate of 25 Gbit/s.

关 键 词：分布反馈(DFB) 激光二极管 大耦合因子 相移光栅 传输矩阵 高成品率 

分 类 号：TN248.4[电子电信—物理电子学]