分子動力學模擬原子轟擊與離子佈植之物理機制研究

Physical mechanisms of atomic bombardment and ionic implantation using molecular dynamics simulations

廖佳鴻(Jia-hung Liau)

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2007年)

摘要

摻雜技術是許多高科技元件中關鍵的技術之一，而高品質的摻雜技術在其半導體製備過程中的製程參數控制對最後的品質有最直接的影響，本文研究的目的將運用分子動力學(Molecular dynamics,MD)模擬原子轟擊及氮摻雜的過程，其次以離子植入法實驗與奈米壓痕(Nano-indentation)實驗來探討奈米尺度下，基材表面受轟擊及摻雜後所產生極薄的影響區於奈米壓痕檢測中的影響。本論文研究內容可分為二部份：首先以分子動力學法基於Morse與Tight- binding勢能模擬銅原子與團簇撞擊基材之機制與行為，並針對靶材加工溫度、入射速度與團簇大小之效應進行分析比較，歸納出最佳之原子植入製程參數。其次以採用Tersoff 多體勢能來描述氮摻雜矽基材之機制與行為，所探討的製程參數包含摻雜速率、摻雜動能及基板溫度。在實驗方面將探討不同植入能量與電流大小對植入深度及濃度分佈的關係，而在奈米機械性質試驗包括：原子力顯微鏡、X-ray繞射、二次離子質譜儀與表面親疏水性分析，最後模擬與實驗結果將作一簡要驗證和比較探討最佳化製程參數。

並列摘要

This thesis aims at the theoretical and experimental study for atomic collision､Ion implantation and nanomechanical characteristics. The study consists of two parts,namely,molecular dynamics simulations analysis and nanomechanical characteristics experiment. In the theoretical stage,simulation codes based on molecular dynamics method were developed to understand the mechanism and behavior of atomic collision and Ion implantation process. In the experimental part,process parameters of nanomechanical characteristics for N-doping silicon such as X-ray､SIMS analysis and load-displacement relations are obtained. Surface and mechanical properties of N-doping silicon was conducted by using atomic force microscope (AFM) and nanoindentation.The XRD result showed that the modified silicon surface exhibited amorphous structure . When the nenrgy of ion implantation increased, the modified surface became rough and had a sualler contact angle. The nanomechanical tests on the samples have revealed a dramatic decrease in the hardness and Young’s modulus with increasing indentation depth. The affecting reason of the investigated factors is discussed as well. Finally,the results of the simulations including molecular dynamics simulation method and Kalypso program were compared with the experimental data.

參考文獻

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