本研究旨在探討以純銀（Ag）電極取代傳統銀鈀（Ag/Pd 80/20）電極於積層式壓敏電阻（Multilayer Varistor, MLV）元件之可行性，期望在降低材料成本的同時，維持甚至提升元件之電氣特性。近年來，隨著電子產品向高整合度與高可靠性方向發展，靜電放電（ESD）及浪湧防護元件的需求大幅增加，如何在確保效能的情況下降低成本，成為壓敏元件製程開發的重要課題。由於貴金屬價格持續攀升，Ag/Pd 合金電極已成為 MLV 製程中最主要的成本來源之一，因此，若能將 Ag/Pd 取代為單一的 Ag 電極，不僅可降低材料費用，亦能簡化製程，對於提升市場競爭力具有重大意義。
然而，純 Ag 在高溫燒結過程中面臨熔點較低的挑戰，容易出現滲入、擴散與球化等問題，進而造成電極剝離、介面反應異常，甚至導致元件失效。因此，本研究不僅針對純 Ag 電極與陶瓷本體之匹配性進行探討，同時亦透過調整玻璃助燒劑組成與 ZnO 粉體粒徑，嘗試開發可於較低溫度下進行的燒結機制，以避免 Ag 擴散失控並確保電性穩定性。本研究採用 V₂O₅ 為主的低溫玻璃系統，並結合粒徑 D50 = 0.5 µm 與 1.1–1.3 µm 的 ZnO 粉體，配合雙階段燒結曲線（蝦燒→主燒），在 910–955 °C 範圍內進行長時間持溫（24–48 h），藉此建立適合純 Ag 電極的最佳化製程條件。
在材料與結構分析方面，本研究透過 SEM、EDS 等技術觀察燒結後的微結構與界面形貌。結果顯示，於 850–900 °C 的最佳條件下，Ag 電極能與陶瓷形成緻密且穩定的結合層，並且界面銀滲透深度顯著降低。當 ZnO 粒徑提升至 1.1–1.3 µm 時，在 V₂O₅ 助燒下可促進晶界液相濕潤，進而獲得更均勻的晶粒分布與穩定的能障結構。相較於使用細小 ZnO 粉體的樣品，大顆粒 ZnO 搭配長時間保溫更能接近商用品之晶粒組織，與市售 SFI 壓敏電阻的 SEM 結構趨勢相符。
在電性特性方面，純 Ag 電極之 MLV 在適當燒結條件下展現與 Ag/Pd 樣品相當的擊穿電壓 (VB) 與電場強度 (EB = VB/厚度)，同時維持低漏電流 (IL) 與穩定的非線性係數 (α)。尤其在浪湧測試中，最佳化樣品的單位體積能量密度 (A/mm³) 具備良好再現性，能承受多次浪湧衝擊而不失效，顯示其可靠性已達到商品化應用的要求。此外，製程重複性測試亦證實，在 910–955 °C、持溫 36–48 h 的雙階段燒結下，所得樣品的浪湧耐量分布集中且可控制，符合品質工程與 SPC 控管需求。
綜合以上結果，本研究證實純 Ag 電極在經過適當製程優化後，能有效解決高溫燒結下的界面不穩定問題，並兼顧成本降低與效能穩定兩大優勢。這不僅對於壓敏電阻產業具有直接的應用價值，也為低溫燒結技術在其他多層陶瓷元件（如電容、感測器等）的應用提供了可行方向。未來可進一步針對不同玻璃組成比例、燒結氣氛控制，以及長期可靠度測試（如 HAST、STOL 與高溫壽命試驗）進行探討，以持續提升純 Ag 電極 MLV 的量產可行性與市場競爭力。

This work investigates the substitution of conventional Ag/Pd (80/20) electrodes with pure Ag electrodes in multilayer varistors (MLVs), aiming to reduce cost without sacrificing performance. Using Ag paste, printing and sintering processes were optimized, and electrical properties such as breakdown voltage, leakage current, and surge endurance were systematically evaluated. Results show that with controlled firing conditions, pure Ag electrodes achieved reliable adhesion to ceramic layers and exhibited stability comparable to Ag/Pd devices. Furthermore, experiments revealed that maintaining sintering between 850–900 °C effectively suppressed Ag diffusion, ensured stable electrode–ceramic interfaces, and preserved surge reliability. These findings demonstrate the potential of pure Ag electrodes for cost-effective and scalable MLV production.

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