利用赫茲接觸彈性解及有限元素法探討底材與中間層對於薄膜機械性質影響

The Effects of Intermediate Layer and Substrate on the Mechanical Properties of Thin Film by Elastic Hertz Contact Solution and Finite Element Method

俞文戈(Wen-Ke Yu)

指導教授 ： 曾信雄

大同大學/工程學院/機械工程學系所/碩士(2005年)

摘要

本研究利用赫茲接觸彈性解及有限元素法探討在不同底材及中間層時對薄膜機械性質的影響。赫茲接觸彈性解可用球型壓痕器模擬，此解可用來研究類鑽碳膜厚、基材與中間層的相互作用。其結果顯示出，薄膜與基材之間的彈性係數差異性大時，鍍膜系統中，基材的相關影響將十分顯著。而中間層的影響將因其厚度、薄膜與基材之間的楊氏模數配合性而異。中間層的厚度將對應力的減少有直接的影響。
另一方面，利用有限元素模型模擬奈米壓痕實驗過程，可求得鍍膜系統和塊材的機械性質，並推斷出材料硬度和楊氏模數。針對矽基材和不同膜厚DLC/Si之負載-位移曲線做探討，並進行數值分析與實驗數據作定性驗證比對，其結果顯示出有相當的一致性。在軟模硬基材下，基材對薄膜硬度影響較小；硬膜軟基材的情況，薄膜硬度易受基材所影響。在鍍膜系統內設計適當中間層，能有效地減少內應力產生並改善附著度。
此項模擬技術在非常薄的膜、混合層等方面應用日漸廣泛。藉由以上二種不同分析方式，冀望對此不同厚度與不同基材之類碳鑽薄膜機械性質及中間層效應有更進一步的了解，並藉此研究提供鍍膜設計研發上的參考。

關鍵字

中間層 ； 基材效應 ； 奈米壓痕

並列摘要

This research uses hertz contact elastic solution and finite element law to discuss the influence on thin film’s mechanical characteristic from using different substrates and intermediate layers. Hertz contact elastic solution, which is used for researching the interaction between DLC, substrate and intermediate layer, can be stimulated by ball shape indentation. The result of this paper demonstrated that, when the elastic coefficient difference between thin film and substrate is considerable, the correlative influence of substrate in film-plated system is extremely remarkable; and the influence of intermediate layer is due to the young’s modulus between its thickness, film and substrate. Intermediate layer’s thickness has the direct influence on reducing stress.

On the other hand, to use finite element models for stimulating Nanoindentation experiment process that can obtain the mechanic characteristics of film-plated system and bulk and can infer the degree of hardness of materials and the young’s modulus. Discussing the loading- displacement curve of Si substrate and different degrees of thickness of DLC/Si, and processing the data analysis and experiment data used for examining stability, we found out that its result was identical. Using the soft-film and hard substrate, the substrate has only a minor influence on the degree of thickness of thin film. Using the hard-film and soft substrate, the thickness of the thin film is prone to influence by the substrate. If we add an intermediate layer in film-plated system, it can efficiently reduce interior stress and improve adhesion.

This simulation technology in extremely thin film or mixture layer and membrane has been applied widely. By using this two analysis methods, depending on the different degree of thickness, the DLC thin film mechanic characteristics of different substrate materials and the effect of intermediate layers, provides understanding and reference for film-plated design and development research.

並列關鍵字

Intermediate layer ； Nanoindentation ； Substrate effect

參考文獻

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