本研究利用多功能X光薄膜繞射儀、穿透式電子顯微鏡(TEM)與掃描式電子顯微鏡（SEM）等儀器，研究積層合金功率電感中Fe-Si-Cr合金粉末與內電極Ag於共燒過程中之反應。實驗結果顯示，在含有O2之大氣環境下熱處理，O2不僅會促使Ag揮發並擴散，導致印刷之線路不連續甚至斷線，更會與Ag以及同樣易揮發之Fe-Si-Cr熱氧化層-Cr2O3，以氣相反應生成大量片狀AgCrO2 (silver chromite)，由於此物質為一種p-type半導體，生成此結晶相會消耗Ag與Cr2O3，最後將導致絕緣電阻不足與崩潰電壓下降等問題。
此外，本研究亦設計實驗以探討片狀AgCrO2之生成機制，研究發現，在熱處理過程中，當溫度低於650 ℃時，Ag與Cr2O3會先反應生成Ag2CrO4 (silver chromate) ，因Ag2CrO4之熔點(658 ℃)低於熱處理溫度(750 ℃)，故在超過658 ℃後，Ag2CrO4容易揮發並沿著粉末間的孔隙移動，與同樣易揮發之Cr2O3藉由氣相反應在粉末間孔隙，甚至擴散至樣品表面，生成大量的六角片狀物AgCrO2，而AgCrO2會在超過800 ℃之後分解為Ag與Cr2O3。

In this study, multipurpose X-Ray thin-film diffractometer, transmission electron microscope (TEM), and scanning electron microscope (SEM) were used to investigate the chemical reaction between Fe-Si-Cr alloy powder and internal electrode, silver, during co-firing for multilayer alloy power inductors. The experimental results show that oxygen not only promotes the volatilization and diffusion of Ag but also causes the printed circuit to become discontinuous or even disconnected, and it will also react with Ag and the volatile Cr2O3 to form a large amount of flaky AgCrO2 (silver chromite). Since AgCrO2 is a p-type semiconductor, the formation of this crystalline phase will consume Ag and Cr2O3, which will eventually lead to the problems of insufficient insulation resistance and the decrease of breakdown voltage.
On the other hand, this study also designed experiments to investigate the formation mechanism of flaky AgCrO2. The experimental results show that silver reacts with the Fe-Si-Cr thermal grown oxide layer, Cr2O3, to form Ag2CrO4 at temperatures under 650 ˚C. The formed Ag2CrO4 with low melting temperature then volatilizes at higher temperatures through the pore channels to react with the volatilized Cr2O3 to form the AgCrO2 via gas phase reaction. Then AgCrO2 will decompose to Ag and Cr2O3 at the temperature higher than 800°C.

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