先進建材：錫鋁與錫銅奈米薄膜顯微組織對電磁波遮蔽特性之影響

Microstructrual Effects of the Sn-Al and Sn-Cu Thin Films on the Electromagnetic Interference Shielding for the Advanced Building Materials

元素錫（Sn） 、鋁（Al） ，銅（Cu） 不僅具備優異之EMI 遮蔽效能，在價格上也擁有競爭力。本研究利用濺鍍Sn-Al 奈米薄膜和Sn-Cu 奈米薄膜檢討結晶機制與膜厚效應對電磁波遮蔽特性之影響，而各鍍膜之高溫製程組織、電導性質與EMI 遮蔽效能之關係也一併比較分析。實驗結果顯示，高溫處理結晶製程能提升Sn-Al 奈米薄膜之EMI 遮蔽性。在低頻條件下，高Cu 原子濃度之Sn-Cu 奈米薄膜不能有效改善EMI 遮蔽性；高溫處理後，低Cu 原子濃度之Sn-Cu 奈米薄膜能提升低頻之EMI 遮蔽性，而高頻下之EMI 遮蔽性則呈現相反趨勢。

The elements Sn, Al and Cu not only possess EMI shield efficiency, but also have acceptable costs. In this study, sputtered Sn-Al thin films and Sn-Cu thin film were used to investigate the effect of the crystallization mechanism and film thickness on the electromagnetic interference (EMI) characteristics. In addition, the annealed microstructure, electrical conductivity and EMI of the Sn-xAl films and the Sn-xCu films were compared. The results show that Sn-Al film increased the electromagnetic interference (EMI) shielding after annealed. For the Sn-Cu films with higher Cu atomic concentration, the low frequency EMI shielding could not be improved. After annealing, the Sn-Cu thin film with lower Cu content possessed excellent EMI shielding at lower frequencies, but had an inverse tendency at higher frequencies.