以空氣作為反應性氣體濺鍍不同形貌之氮化鈦薄膜研究

Sputtering deposition of titanium nitride thin films with different morphologies using air as a reactive gas

葉仁琇(Jen-Hsiu Yeh)

指導教授 ： 呂福興

國立中興大學/工學院/材料科學與工程學系所/碩士(2012年)

摘要

本研究主要是以空氣作為反應性氣體在濺鍍法中利用田口實驗法找出改變薄膜表面形貌的控制因子，並以變異數分析S/N圖表分析找出控制薄膜形貌的關鍵因子，目前尚未有文獻是以空氣為反應性氣體製備不同形貌的TiN薄膜，故本研究在節能及應用性上皆有很大的效益，對於本研究的摘要我們敘述如下。
實驗一開始以「田口實驗L934」(L代表田口直交表9代表實驗次數，3代表水準，4代表控制因子)選定四個能改變薄膜表面形貌的控制因子，並將所鍍著之試片初步進行薄膜確認分析以X光繞射儀(XRD)確認結晶相，以四點探針進行電性分析，判定田口實驗中的試片皆為氮化鈦薄膜。接著再以場發射掃描式電子顯微鏡(FE-SEM)觀察薄膜的微結構與表面形貌，原子力顯微鏡( AFM)來進行表面形貌的粗糙度分析，並量化數據。
在本研究中，主要為製備出不同形貌的氮化鈦薄膜，在特性需求上是以粗糙度望大及望小特性作為不同形貌的依據，並將分析結果利用田口實驗中的變異數分析，計算出四個控制因子中兩種特性的貢獻率及最佳製程參數。結果顯示在粗糙度望大部份貢獻率為基座轉速39 %、基板偏壓36 %、濺射功率12 %、靶基間距15 %，在粗糙度望小部份貢獻率為基座轉速38 %、基板偏壓25 %、濺射功率9 %、靶基間距28 %。之後將兩組特性參數分析整合，也就是當基板偏壓為-50 V，濺射功率為300 W，靶基間距為14 cm時，控制不同基板轉速就能製備出不同形貌的薄膜。結果證實關鍵因子確實能影響薄膜的表面形貌及薄膜的粗糙度。最後在以下的製程區間:低轉速(0~15 rpm)、低偏壓(-50 V)、短間距(8 cm)、低功率(300 W)就可製備出粗糙度在(2.0~3.5 nm)晶粒尺寸(38±6 nm)表面形貌為鱗片狀的TiN薄膜；若以高轉速(20~36 rpm)、中偏壓(-150 V)、長間距(14 cm)、中功率(400 W)的條件即可製備出粗糙度範圍在1.0~1.3 nm晶粒尺寸(12±3 nm)表面形貌為顆粒狀的TiN薄膜。

關鍵字

空氣 ； 濺鍍 ； 氮化鈦薄膜

並列摘要

This study is using the air as the reactive gas in the sputtering method and use Taguchi method to identify the control factors that influenc the thin film surface morphology. Then use the analysis of variance and S/N chart to find the key factors that controll the thin film morphology. There is no literature based on air as reactive gas to prepare different morphologies of the TiN film. Therefore, this study is beneficial to energy efficiency and functionality. We described the contents as follow for this study.
The begning of the experiment apply "Taguchi method"(L934, L represents Taguchi table, 9 represents the times of experiments, 3 represents level, 4 represents control factors) select four control factors that can influence the film morphology. The initial analysis of crystalline phase of the specimen is confirmed by X-ray diffraction. Electronic property of the TiN film can be confirmed by four-point probe. The surface morphology and microstructure can be observed by the field-emission scanning electron microscope. The roughness of film surface can be analyzed by atomic force microscope, and the data can be quantified.
In this study, mainly for the preparation of different morphology of titanium nitride film, based on the demanded characteristics, expecting great or small of the roughness as the basis of different morphology, and the results by the analysis of variance in Taguchi experiment to obtain two characteristics of the four control factors in the contribution rate and the best process parameters. The results shows that at the excepting great of the roughness, the major contribution rate is the speed of the plate 39%, then the bias voltage of the substrate 36%, sputtering power is 12%, the spacing between the target and plate is 15%. At the excepting small of the roughness, the major contribution rate is aslo the speed of the plate 38%, then the bias voltage of the substrate is 25%, sputtering power is 9%, the spacing between the target and plate is 28%. Later analysis of the integration of two characteristic parameters, that is, when the substrate bias is -50 V, sputtering power is 300 W, the spacing between the target and plate is 14 cm, by controling the different speed of substrates could prepare different morphologies of the film. The results indicate the key factors can really affect the surface morphology and roughness of the film. Finally, the process in the following range: low speed (0 ~ 15 rpm), low bias (-50 V), short distance (8 cm),low-power (300 W) can prepare the TiN films that roughness is between 2.0 ~ 3.5 nm, grain size is at the range of (38 ± 6 nm) as a scaly surface morphology. If the process in the following range: high-speed (20 ~ 36 rpm), medium bias voltage (-150 V), long distance (14 cm), medium power (400 W) can prepare TiN films that roughness in the range 1.0 ~ 1.3 nm grain size (12 ± 3 nm) as a granular surface morphology.

並列關鍵字

air ； PVD ； titanium nitride thin films

參考文獻

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