| 摘要: | 隨著第五代行動通訊（5G）的快速發展，全球對高頻訊號傳輸的需求持續攀升，推動了物聯網（IoT）、人工智慧（AI）、智慧製造等應用的成長。相較於4G，5G不僅在傳輸速度、延遲和連接能力上有明顯提升，也對硬體材料的性能提出更嚴苛的要求，特別是在印刷電路板（PCB）等關鍵元件的介電特性與訊號完整性方面。近年來，玻璃電路板（Glass PCB） 因具備優異的高頻性能與結構穩定性，逐漸成為新一代高頻高速通訊設備的重要發展方向。
玻璃因具備低介電損耗、低介電常數、高電阻率、耐腐蝕性強及優異的尺寸穩定性，逐漸成為高頻電子與先進封裝的重要材料。相比傳統高分子基板，玻璃在高溫環境下仍能保持平整、不易變形，並已應用於玻璃中介層、射頻元件、光子學平台與微流道封裝等。然而，玻璃與金屬間存在明顯的熱膨脹係數差異，加上玻璃表面潤濕性差、表面能低且缺乏活性官能基，使得傳統金屬化製程（如電鍍、化學鍍）需依賴多重前處理以提升附著力，不僅製程複雜、成本高昂，還伴隨環境污染問題。
雷射透射式焊接（Laser Transmission Welding, LTW）被視為具潛力的替代方案。該技術利用雷射穿透透明基材，在與金屬層的界面產生局部加熱與熔融，實現異質材料接合。LTW具備製程精確、避免大面積損傷及可減少化學藥劑使用等優點，原先主要用於聚合物與金屬接合，如今也逐漸應用於玻璃與金屬的結合。
本研究採用波長515 nm的綠光飛秒雷射，嘗試將低粗糙度銅箔直接接合玻璃基板並金屬圖案化，並評估其黏附性與電性表現。該方法可省略傳統濕式製程中的多道處理，減少能源消耗與污染，同時提升接合強度與高頻性能穩定性。
;With the rapid advancement of fifth-generation mobile communication (5G), global de-mand for high-frequency signal transmission continues to rise, driving the growth of applica-tions such as the Internet of Things (IoT), artificial intelligence (AI), and smart manufacturing. Compared with 4G, 5G not only offers significant improvements in transmission speed, latency, and connectivity but also imposes more stringent performance requirements on hardware mate-rials—particularly in terms of the dielectric properties and signal integrity of key components such as printed circuit boards (PCBs). In recent years, glass PCBs have emerged as a promising development direction for next-generation high-frequency, high-speed communication devices, owing to their superior high-frequency performance and structural stability.
Glass, with its low dielectric loss, low dielectric constant, high resistivity, strong corrosion resistance, and excellent dimensional stability, has become an important material for high-frequency electronics and advanced packaging. Compared with conventional polymer substrates, glass maintains exceptional flatness and resists deformation even under high-temperature conditions, and has been applied in glass interposers, radio-frequency compo-nents, photonic platforms, and microfluidic packaging. However, the significant difference in the coefficient of thermal expansion (CTE) between glass and metals, along with glass’s inher-ently poor wettability, low surface energy, and lack of active functional groups, means that conventional metallization processes—such as electroplating and electroless plating—require multiple pre-treatment steps to enhance adhesion. These processes are not only complex and costly but also raise environmental pollution concerns.
Laser Transmission Welding (LTW) has been recognized as a promising alternative. This technique uses a laser to penetrate a transparent substrate, generating localized heating and melting at the interface with the metal layer to achieve dissimilar material bonding. LTW offers high processing precision, avoids large-area damage, and reduces the use of chemical agents. Initially developed for polymer–metal bonding, it has increasingly been applied to glass–metal joining.
In this study, a 515 nm green femtosecond laser is employed to directly bond low-roughness copper foil onto glass substrates and perform metallization patterning, with evaluations of adhesion strength and electrical performance. This approach eliminates multiple steps in conventional wet processes, reduces energy consumption and pollution, and simultane-ously enhances bonding strength and high-frequency performance stability. |
