| In recent years,semiconductor lasers have been increasingly used in industrial,agricultural,military,and medical fields.Laser hair removal,as the main component of laser medical filed,is quite mature in European and the United States,and its market share in China is also increasing.However,semiconductor laser module and chip for hair removal are monopolized by foreign laser industry giants.Due to the inherent working principle of semiconductor lasers,a large amount of heat will inevitably be generated during the work,and the heat accumulation will seriously affect the work efficiency and reliability of the laser.Microchannel heat sink is often used to solve the heat dissipation of laser modules in foreign countries,but their structures are complex and costly.In order to reduce the cost of semiconductor laser module for hair removal and facilitate the popularization and application,there have been related research reports on the use of macro-channel heat sinks instead of micro-channels in China.In view of this problem,based on the structural characteristics of the macro-channel laser module,this paper has carried out basic research around the core group structure and heat sink form of the economical macro-channel laser module.(1)The traditional integrated core group form of the macro channel laser module is changed and an independent unit core group is designed to facilitate the pre-screening of domestic laser hair removal chips with low quality at present,to improve the module package yield,to promote the practicality and to reduce the cost of chip.Reducing the difficulty of core group packaging and sintering,improving the uniformity of the temperature field distribution of the module core group array,reducing the chip packaging stress,and increasing the life of the laser module.ANSYS is used to analyze the relationship between the thickness of the insulating ceramic sheet and the chip junction temperature in the core unit for determining the material and thickness of the insulating ceramic sheet and saving material cost.(2)The structure of the macro channel laser module heat sink structure is instead of a heat sink with diamond tooth.Taking the temperature field distribution of the module core group array as a reference,Fluent is used for verifing the heat dissipation uniformity of thediamond tooth heat sink relative to the square tooth form.Using the chip junction temperature as a criterion,the CFDesign fluid simulation software was used to analyze and to compare with the heat dissipation levels of the microchannel and the diamond tooth macrochannel.The Orthogonal experiment was used to design the key parameter of the diamond tooth,making the macrochannel module more portable.ANSYS analysis proves that the thermal stress of the chip package’s independent unit core group is reduced by about 50% compared with the integrated core chip package.The cost of the diamond-shaped macro-channel was calculated to be nearly 70% lower than that of foreign micro-channel.(3)The module packaging process is formulated to ensure module performance and life.A convenient sintering fixture is designed for independent unit core groups to improve the quality and efficiency of packaging and to reduce packaging cost.According to the related factors of the sintering cavity,the vacuum degree of the sintering furnace is setted to reduce the cavity of the sintered solder layer.The chip cavity surface inspection specification is formulated to screen out defective units.The packaged laser module is used for sample preparation,and the pyroelectric laser power meter is used to test the laser power and spectral change of the module sample,which shows that it meets the requirements for use.The aging experiment estimates that the module life reached 20000 h,which reaches the practical level. |
