優化介電層沉積製程以減少金屬與金屬間裂縫之研究

Reduction of Metal to Metal Crack by Optimization of Dielectric Deposition Processes

陳宗銘(Tsung-MING Chen)

指導教授 ： 趙天生

國立交通大學/理學院/理學院應用科技學程/碩士(2019年)

摘要

本篇論文因半導體不斷演進微縮但晶片所效能卻被限制，為了達到輕薄短小得需求最簡單途徑就是降低串聯電阻，因而將最上層金屬層厚度增加但隨著金屬厚度越來越厚產生伸張應力也隨著變大，導致護層包覆金屬與金屬層時常因金屬伸張應力太大而在金屬與金屬間產生裂縫，使電性測試時漏電。
本篇論文概論以金屬拉伸應力與薄膜壓縮應力不匹配而產生裂縫之研究。探討金屬伸張應力對氧化層影響、氧化矽薄膜的成原理與成長機制以及各種製程參數的變化(包括，反應氣體的流量，功率等)對於氧化矽薄薄膜特性的影響，這些薄膜特性包括了薄膜應力、薄膜沉積速率、薄膜密度等特性。
透過實驗設計法，漸進的方式篩選出影響薄膜特性製程參數及範圍，發現O2流量與功率降低產生薄膜較大壓縮內應力，這個現象可大幅減緩因金屬厚度增加所產生伸張應力，當功率降低時大量氧化不完全的SiHn自由基導致氧化矽薄膜的Si-H 鍵結濃度明顯上升，透過適當退火步驟與製程參數調整得到了具有極高薄膜內應力鬆散的氧化薄膜與金屬伸張應力做匹配使應力得到釋放減緩金屬與金屬層間裂縫產生。
在結論中我們將規劃出未來可以改進的方向，使用會不同影響氧化矽薄膜對金屬層產生裂縫進行研究，並以藉缺陷檢測儀與測試從中尋找最佳化條件讓金屬與金屬裂縫減少。

關鍵字

介電層 ； 金屬層

並列摘要

In this work we report increase in the thickness of the metal layer for passivation crack issue, which resulted from the crack issue between the metal and the metal due to the stress mismatch between the tensile stress and the compressive stress of the film. First, we chose the way to find affecting process and range by experiment design methods.
We found that power and O2 were reducing to intense compressive stress .It was found that the flow and power of O2 were reduced, and the compressive internal stress of the film was reduced.
This phenomenon can greatly reduce the tensile stress caused by the increase of the thickness of the metal and the decomposition rate decreases when the power is insufficient. This phenomenon can reduce the tensile stress caused by the increase in metal thickness.
When the power is under-power, the decomposition rate decreases and the direct deposition of a large amount of incompletely oxidized SiHn radicals leads to an increasing in the Si-H bond concentration of the yttrium oxide film, which is successfully adjusted by a proper annealing step and process.
It has a very low film internal stress to reduce and the product has no metal layer cracks. In the conclusion, we will plan the direction that can be improved in the future, use the different influences on the oxide film to study crack the metal layer and use the defect detector to find the optimal conditions to make the metal layer complete.

並列關鍵字

Dielectric ； Metal

參考文獻

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