| Summary: | 碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 101 === Because of economic feasibility, dimensions control and low processing temperature, the reaction-bonded silicon nitride (RBSN) process has received extensive attention. The microstructure and thermal conductivity of the reaction-bonded silicon nitride (RBSN) specimens, containing 2wt% Fe and 2wt% Y2O3, were investigated in the present study. The addition of iron promotes the extent of nitridation and the relative density of the RBSN. The addition of Fe also affects the α→β Si3N4 transformation and induces the formation of rod-like β-Si3N4. The addition of Y2O3 reduces the amount of silicon oxide through the reaction of SiO2 to form Y2Si2O7 phase. In the present study, the effects of stepwise heating profile on the nitridation are also investigated.
In the present study, a eutectic bonding technique is used to join copper plate to reaction-bonded silicon nitride. The RBSN specimens were oxidized first at 1300°C. The copper plate was also oxidized at various temperatures. The microstructure and thermal conductivity of RBSN/Cu laminate were investigated in the present study. The bonding was achieved as the extent of oxidation is high. The morphology of SiO2 layer affected the wetting between RBSN and Cu. To the resolution of the scanning electron microscope, no Si-Cu-O compound is found at the interface between oxidized RBSN and copper. The infiltration of Cu-O melt into the SiO2 layer helps the bonding between RBSN and Cu.
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