Study On Construction Of Thermal Conductivity Measurement Platform Based On 3-Omega Method And Its Application

With the continuous development of modern science and technology,various electronic devices and equipment have become miniaturized and integrated,and the power density has rapidly increased.Convenient and accurate measurement of the thermal conductivity of materials of various sizes and phases has become an important issue to solve the problem of component thermal management.3-Omega technology,as a thermal property measurement method with wide application range,high accuracy and relatively low cost,is of great significance for in-depth research and optimization of test technology.First,this dissert introduces the significance of the study of the material’s thermal properties and some common thermal conductivity measurement methods.Through comparison,the advantages of 3-Omega technology for measuring the thermal conductivity of the material are clarified.Then introduced the development context and specific status of this method,expounded its basic measurement principle,pointed out that the shortcomings of the current measurement technology lied in the low degree of modularization and automation,and the system block diagram of the test platform is clarified by the system requirements analysis method.Then this dissertation proposes and implements a hardware design using parallel digital-to-analog converters to form a signal attenuator,combined with an operational amplifier to form a self-designed harmonic method test hardware control system,and designs and writes a matching system in the Lab VIEW software environment.Modular software control system.It embodies modular,automated,and standardized hardware design ideas.The use of a universal BNC interface and an independent sample compartment ensures the maximum scalability of the system,making it suitable for the heating of solid,liquid,gas and other different materials Conductivity is automatically measured.Third,in order to verify the feasibility of the experimental platform,the system is used in conjunction with the PPMS system to test the specific relationship between the resistance value of the chromium/gold thin film resistance wire on the sample and the temperature,and finally obtained the temperature coefficient of resistance of0.002475/K,and the literature The values are consistent,and then the thermal conductivity of the standard sample borosilicate glass and silicon substrate was measured,of which the thermal conductivity of Pyrex7740 is 1.12 W/m K.It is slightly lower than the accepted value ofκ = 1.12 W/m K but it can still prove the effectiveness of the equipment.The results of the silicon substrate produced a large error.After analysis,the effects of thermal radiation and thermal convection were ruled out,and it was finally found that the sample itself might be the cause.In summary,this thesis uses a combination of 3-Omega method principles and practical requirements for research.According to the basic requirements of the 3-Omega method measurement and the current difficulties,an automated thermal conductivity test system was designed and built,and the feasibility of the system was verified.It fills the blank of automated testing on the experimental platform and provides support for the further research and promotion of the 3-Omega method.