本文探討添加氧化銅(CuO)的二氧化鈦(TiO2)在低於其共晶溫度時的燒結機制。
於TiO2中添加奈米尺度的CuO 達0.5wt%以上，即可在低於共晶溫度的875℃持溫2小時下燒結緻密，經由熱差分析與表面成分分析，確認此條件下尚未生成液相而排除了液相燒結的可能性，並經由微結構觀察、成分與阻抗頻譜分析後得知：緻密的條件為一種富含Cu的薄膜存在於晶粒之間，此薄膜加速了晶粒間的擴散，進而使TiO2-CuO在低於共晶溫度下的溫度就能燒結緻密。
而緻密的試片在3.7GHz的共振頻率下，介電常數可達100以上，介電損失達0.3%以下，品質因子可達1.5× 104以上。

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