Fabrication And Characterization Of High Speed 850nm Vertical Cavity Surface Emitting Lasers

Vertical cavity surface emitting lasers play an important role in the short-distance optical interconnection attributed to their advantages,such as low cost,low threshold current,high modulation bandwidth and low power consumption.With the development of big-data and supercomputer technology,the performance demand of short-distance optical interconnection is increasing quickly,which also proposes a challenge for high-speed 850nm VCSEL.The main objective of this paper is to improve the modulation bandwidth of 850nm VCSEL.The factors limiting the bandwidth of VCSEL high-speed modulation are deeply studied.The effects of dry etching technology,BCB filling technology,oxidation technology and metal deposition technology on the high-speed modulation performance of 850nm VCSEL were analyzed in detail.Finally,the-3d B modulation bandwidth of 10.06 GHz was achieved in the VCSEL.The main research contents of this paper are summarized as follows:(1)The micro-nano processing processes related to the preparation of vertical cavity surface emitting lasers are introduced in detail,including lithography,dry etching,BCB filling technology,oxidation and metal deposition.The characteristics of photosensitive BCB are introduced,and the process parameters are finally determined through experiments.(2)The influence of alloy temperature on resistance was studied.The resistance of the N electrode and P electrode at different temperatures were calculated by using the dot transmission line model.Finally,the temperature of the alloy with the minimum resistance of N and P electrode is 300?and 420?respectively.(3)The effects of oxidation time and mesa size on device performance were studied.It is found that the shape of the oxidation pore will change into an irregular pattern with a too long oxidation time when other conditions were the same.Compared with the small mesa device,the oxidation pore shape of the device with a larger mesa size is closer to the circle after oxidation.(4)The effect of the current limiting hole on VCSEL high speed modulation is studied.Oxidized and unoxidized 850nm VCSELs were prepared and static tests were run.The results show that the threshold current of the devices with oxidation is relatively small.The oxidation process is one of the key processes to realize high speed VCSEL.The quality oxidation process requires proper oxidation time,intact surface condition of the device after oxidation and circular oxidation hole.(5)High-speed VCSEL was fabrication.Through build the static characteristics test system is tested,and tested its dynamic characteristics through the vector network analyzer,analyses the test results,the threshold current is10 m A,differential resistance is 68?.The maximum output optical power is 0.981m W and the bandwidth is10.06GHz.The MCEF is 1.7245GHz/m A^1/2 and the D factor is 1.08GHz/m A^1/2...