| 摘要: | 隨著物聯網與高頻通訊時代的來臨，在數據量爆增的趨勢下，搭配高頻元件與高頻傳輸所需的電路板也成為必須。玻璃具優異絕緣性，相較於高分子材料與矽基板，擁有更好的介電性能，可減少傳輸過程之介電損耗且其尺寸製作也不會受限制，因此，玻璃電路板逐漸受到重視。但也因玻璃具優異的物理與化學穩定性，玻璃基板上的導電金屬製作困難度高，金屬導體與玻璃基板間的足夠附著力是嚴峻的挑戰。本研究結合雷射圖案化與無電鍍銅兩技術，在玻璃基板上製作具高黏著力的銅導線。本研究採用鋁矽酸玻璃基板，藉由超快雷射之汽化機制在玻璃形成電路圖案凹槽，再浸入無電鍍液中沉積銅電極，從而得到具電路圖案之玻璃電路板。本研究首先測試雷射玻璃處理參數，在固定脈衝重疊率 ( Pulse Overlapping, PO ) 97.5%與掃描重疊率 ( Scanning Overlapping, SO ) 75%下，分別使用能量密度3.37、2.21與1.69 J/cm2做測試，結果顯示，使用較高能量密度可獲得較佳之電性，而不同的鋁矽酸玻璃也因其組成成份的不同，產生不同的銅沉積形貌與不同的電性。在玻璃與銅介面的微觀面，本研究分析介面接合機理方面，以各式不同的文獻作為前期推論方向後，根據TEM微觀結構形貌所獲得的晶格狀態與前期文獻資料，發現玻璃雷射汽化表面會因無電鍍液滲入，使玻璃內之鋁離子被銅離子置換；使用TEM分析，也發現沿汽化界面之玻璃內部有銅元素存在，TEM之繞射圖案也顯示於玻璃內部靠近表面處成多晶相，此存在於介面的銅，除了可作為無電鍍之晶種外，也具有機械錨定效用，使後續無電鍍之銅金屬與玻璃之間產生良好的黏著力。進一步，本研究也作熱循環測試，在高溫與低溫來回循環後，無電鍍銅電極仍具有良好的導電性並可有效地黏貼在玻璃基板上。相較於傳統無電鍍製程，須在玻璃上先進行敏化及活化等步驟以預先形成晶種圖案，本研究可有效流程簡化，製作出微米級之銅導線。;With the advent of the era of Internet of Things and high-frequency communication and under the trend of explosive growth of data volume, both high-frequency devices and circuit boards are required to match the requirement of high-frequency transmission. Glass has excellent insulating properties. Compared with polymer materials and silicon substrates, it has better dielectric properties, which can reduce the dielectric loss during transmission and has high flexibility in size scaling compared to silicon. Therefore, Glass Printed Circuit Boards ( G-PCB ) attracted more attention. However, due to the excellent physical and chemical stability of glass, it is difficult to manufacture conductive metals on glass substrates, and sufficient adhesion between metal and glass substrates is a serious challenge. This study combines both techniques of laser patterning and electroless copper plating to fabricate copper wires with high adhesion on glass substrates. In this study, aluminosilicate glass substrate was used to form circuit pattern grooves in glass by the ultrafast laser induced ablation first, then the glass was immersed in electroless plating solution to deposit copper electrodes to obtain a patterned glass circuit board. The appropriate laser processing parameter sets were experimentally obtained as: the pulse overlap rate (Pulse Overlapping, PO) was 97.5%, the scanning overlap rate (Scanning Overlapping, SO) was 75%, and the energy density was 3.37, 2.21 or 1.69 J/cm2, respectively. Results show that better electrical properties can be obtained with higher energy density, and various aluminosilicate glasses have different copper deposition morphologies and electrical properties due to their intrinsic differences in compositions. This study analyzes the interface bonding mechanism based on the microscopic images on the glass-copper interface. According to TEM images and comparing that with the results in the literature, it is found that the glass laser-ablated surface was infiltrated by the electroless plating solution, so that the aluminum ions in the glass were replaced by copper ions. It was also found that copper elements exist inside the glass along the laser-ablated surface. TEM diffraction pattern further displayed that a polycrystalline phase was formed. The fact that copper presented at the interface not only served as a seed crystal for electroless deposition, but also acted as a mechanical anchor. As a result, the adhesiveness of electroless copper deposition and glass was favorable. The thermal cycle test was also performed to further examine the copper adhesion. After several back-and-forth cycles between high and low temperatures, the electroless copper still showed good electrical conductivity and effective adhesion to the glass substrate. Compared with the traditional electroless copper plating process that the steps such as sensitization and activation must be performed on the glass to form the seed pattern in advance, this study can effectively simplify the process and produce micron-scale copper wires. |
