Research On Package Structure Design And Thermal Management Technology Of High Power Semiconductor Laser

Since the birth of semiconductor laser in 1960 s,it has gradually become a strong pillar of modern information and the focus of international high-tech competition.With the rapid development of science and technology,the demand for output power and service life of semiconductor laser is increasing.Due to various energy losses in the active region of semiconductor laser,more heat is produced in the device,which seriously affects the reliability of semiconductor laser.Therefore,it is of great practical significance in the field of semiconductor lasers to optimize the packaging structure and study the thermal management technology of semiconductor lasers.Based on the theory of thermal characteristics of semiconductor lasers,this paper analyzes the various heat generation mechanisms of semiconductor lasers and the effects of temperature on the threshold current,operating wavelength,output power and service life of semiconductor lasers.The basic theory of heat transfer and ANSYS finite element analysis method are analyzed and summarized,which provides the theoretical basis for studying the thermal characteristics of semiconductor lasers,reducing the temperature of the active region of semiconductor lasers,and improving the reliability of devices.The main contents of this paper can be divided into the following aspects:(1)In order to improve the heat dissipation efficiency of single tube packaging of semiconductor laser based on C-Mount packaging,a new heat sink material with high thermal conductivity graphite sheet as auxiliary heat sink is proposed,and step heat sink structure is adopted.Through the simulation calculation of ANSYS software,it can be seen that the temperature of the active region of the semiconductor laser is reduced by about 6.163 k,so as to reduce the temperature of the active region of the semiconductor laser and improve the output power of the semiconductor laser.(2)It is proposed that highly oriented pyrolytic graphite sheets with through-hole structure are used as auxiliary heat sink to reduce the temperature of the active region of the semiconductor laser array.The effect of different graphite sheet through-hole structures on the temperature of each emitter of the semiconductor laser was studied.By optimizing the graphite sheet through hole structure,the maximum temperature of the semiconductor laser array was reduced by 4.556 K,and the temperature difference of each emitter is reduced by 5.756 k.The purpose of reducing the operating temperature of the semiconductor laser array and improving the temperature uniformity of each emitters of the semiconductor laser array is achieved.(3)Through hole graphite and common graphite were metallized,and two kinds of graphite were used as heat sink for semiconductor laser packaging.P-U-I and wavelength were measured at different ambient temperatures.The through-hole graphite heat sink structure has lower package thermal resistance and can effectively reduce the temperature of the active region of the semiconductor laser.(4)Based on the CS package type of semiconductor laser array,the influence of thermal conductivity of transition heat sink material on the temperature uniformity of the array is analyzed,and a new package heat sink structure of aluminum nitride and copper based diamond step composite heat sink is proposed.By optimizing the step parameters to change the temperature distribution of the step composite heat sink,the temperature uniformity of each emitter of the semiconductor laser array can be improved.