Research And Testing Of The Thermal Properties Of Thin-film Materials

Film as one of the most common form of the material existence has been widely used in MEMS and microelectronic devices, and occupies an important position, the current study about micro scale heat focuses on the film. Thermal parameters of the film determine the thermal performance of the device, and it is an important basis for establishing the heat balance equation and doing thermal analysis of the device. Therefore, it is of great significance to quantitatively analysis the thermal parameters of the micro/nano-film for the device research and development.This paper is based on the micro scale heat transfer theory. a method of thermal conductivity and heat capacity measurement of multilayer films is introduced, and the production of test structure has been finished for the final processing that the thermal conductivity and heat capacity values is measured. First, the common test methods of thermal properties of film are theoretical analyzed, based on existing methods, after optimization and design, we put forward the comparison method for thermal conductivity test and the suspended membrane method for heat capacity test of multi-layer film. And the simulation results are consistent with the theoretical value which verifies the feasibility of the method. Secondly, the production process of the test structure is introduced; the total test structure is made of micro-machining technology, including the bulk micromachining and surface micromachining. Coating technologies used in PECVD, sputtering, vacuum evaporation, using photolithography, wet etching, dry plasma etching process with a sacrificial layer to produce micro-bridge structure. Then we get the thermal conductivity by comparison test method, and then we test out the thermal time constant of suspended membrane, after that we calculate the thermal conductivity of suspended membrane, ultimately, the heat capacity of multilayer films has been calculated. Finally the error of the experimental results is analyzed and the shortcomings of this article are summarized, and we also outlook the future research.