- 學位論文
水平排列奈米碳管互聯結構應用於半導體先進封裝技術
Horizontally Aligned Carbon Nano-tube (HA-CNT) Interconnect Applied in Advanced Packaging Technology for Semiconductors
摘要
隨著半導體元件尺寸不斷微縮並逐漸接近物理瓶頸，先進封裝技術成為延續莫爾定律關鍵之一，其中的2.5D以及3D立體封裝技術即透過矽中介層(Silicon interposer)、導線重佈層(Redistribution Layer, RDL)、矽穿孔(Through Silicon Via, TSV)等結構達成晶片間的互聯(Interconnect)。目前於互聯技術中，銅金屬被作為主要的導線材料，但隨著製程技術的發展，電子元件的物理尺寸也不斷縮小。此時，在高電流密度的條件下，理想中的導線材料須滿足高抗電遷移能力、低電阻以及良好的散熱特性，而奈米碳管(carbon nanotube, CNT)同時具備了超越傳統金屬的電性、散熱特性與機械強度之潛力，因而被視為下一代革命性之新型互聯材料。本論文提出使用水平排列奈米碳管取代封裝結構中的傳統金屬導線之概念，透過創新製程以及最佳化參數製備高品質水平排列奈米碳管，並示範碳基互聯之概念實作。以圖案化鐵薄膜及氧化鋁作為催化層，並透過熱化學氣相沉積法生長垂直排列奈米碳管，使用液體輔助展平法以及多種改良製程將垂直排列奈米碳管展平至水平排列奈米碳管，透過氧電漿蝕刻以圖案化水平奈米碳管導線，並於兩端蒸鍍製備金屬電極來完成碳基互聯測試結構。於奈米碳管製備階段透過掃描式電子顯微鏡、拉曼光譜分析儀器以及三倍頻熱傳導值系統量測並分析奈米碳管生長品質以及熱傳導值表現，最後藉由兩點探針系統對水平排列奈米碳管互聯結構進行電性量測，驗證並評估使用奈米碳管取代封裝結構中傳統金屬互聯的可行性。
並列摘要
Carbon nanotubes (CNTs) have emerged as a promising next-generation interconnect material due to their outstanding electrical properties, thermal conductivity, and mechanical strength surpassing traditional metals. This paper proposes the concept of replacing traditional metal interconnect in packaging structures with horizontally aligned carbon nanotubes (HA-CNTs). Innovative processes are employed to prepare high-quality HA-CNTs, demonstrating the implementation of carbon-based interconnect concepts. Using patterned iron films and alumina as catalytic layers, vertically aligned carbon nanotubes (VA-CNTs) are grown through chemical vapor deposition. Liquid-assisted planarization methods and various improvement processes are utilized to flatten the VA-CNTs into HA-CNTs. Oxygen plasma etching is employed to pattern the HA-CNT interconnect, and metal electrodes are deposited at both ends to complete the carbon-based interconnect test structure. Throughout the stages of fabrication, scanning electron microscopy, Raman spectroscopy analysis, and thermal conductivity measurements are conducted to assess the growth quality and thermal performance of the CNTs. Finally, electrical measurements using a two-point probe system are performed on the HA-CNTs interconnect structure to validate the feasibility of using nanotubes as a replacement for traditional metal interconnects in packaging structures.