Thermal Characterization And Design Of Vertical Cavity Surface Emitting Semiconductor Laser Arrays

Vertical-Cavity Surface-Emitting Laser(VCSEL)has the advantages of stable singlewavelength operation,low threshold current,low divergence angle and circular symmetric spot,etc.Especially,it can emit laser on the chip surface,which is easier to integrate highdensity two-dimensional arrays,and is used in LIDAR,laser printing,data transmission,etc,data transmission and many other fields.However,the incorporation of distributed Bragg reflector structure in VCSELs aggravates the thermal effect inside the device,especially in VCSEL arrays,where the heat generated by the device units also interacts with each other to produce thermal crosstalk,thus making the thermal effect of arrays more severe compared to that of single tubes.Severe thermal crosstalk can reduce the output power of VCSEL arrays and deteriorate the output beam quality,thus affecting the device lifetime and reliability.Therefore,it is important to study the mechanism of heat generation in VCSEL arrays and the reduction of thermal crosstalk in array cells.The research in this paper can be divided into the following three areas:(1)Thermal characterization and design of VCSEL arraysThe thermal characteristics of the vertical cavity surface emitting laser are studied,and the thermal mechanism inside the VCSEL array is analyzed,and the thermal simulation of the VCSEL array is carried out by using the finite element analysis method.39.882 ℃,and the cell spacing of 36μm,the temperature is reduced by about 7 ℃,at this time,the thermal crosstalk of the array cells is weakened,the heat dissipation effect is better,the chip utilization rate is higher.(2)Diamond-based heat sink structure design for VCSEL arraysIn order to reduce the cell temperature difference of the vertical cavity surface emitting laser array,weaken the thermal crosstalk effect on the center region of the array,and make the array cells emit more uniformly,the diamond composite heat sink package structure based on different micro-slot structures is designed to optimize the heat dissipation of VCSEL arrays.The effect of the shape and position of the microgroove structure on the temperature difference between the cells is investigated,and it is found that the temperature difference between the array cells is the lowest at 2.582°C when the microgroove shape is square ringshaped and located directly below the emitting cells.(3)Study on the preparation process of vertical cavity surface emitting semiconductor laser array devicesThe VCSEL array preparation process is studied,and reasonable experimental parameters and process flow are used to prepare VCSEL array devices.In view of the simulation results,the VCSELs with different package structures are packaged and tested,and the final output power of the devices is analyzed,and compared with the simulation results,it is concluded that the output power of the composite heat-sink VCSEL array with square ring microgroove structure is increased by 17.241%.