現今Ta-N阻障層為積體電路之內連接導線系統之主流，但由於Ta-N薄膜中其晶界為銅原子高溫擴散之途徑，因此本實驗採用非晶質態薄膜Ta-Si-N作為擴散阻障層應用於銅內連接導線系統中，期待利用其非晶質態的特性能有效阻礙銅原子的擴散。
本研究第一部分藉由控制鉭靶及矽靶的功率，搭配不同流量的氮氣氣氛進行反應性濺鍍，濺鍍出不同成分的鉭-矽-氮( Ta-Si-N )薄膜。之後以掃描式電子顯微鏡( SEM )觀察表面、以X射線光電子能譜儀( XPS )分析化學鍵結、以低掠角X光繞射(GIAXRD)分析結晶相、使用拉塞福背向散射技術( RBS )作成份分析及密度測量，並做片電阻及膜厚量測計算薄膜電阻率，探討濺鍍製程與鉭-矽-氮薄膜微結構間之關聯性。
第二部分則將銅濺鍍於不同成分之Ta-Si-N/SiO2/Si結構上，經500 ~ 900 ℃真空爐管退火。並以掃描式電子顯微鏡(SEM)觀察表面、以低掠角繞射(GIAXRD)分析結晶相，並做片電阻量測探討銅在氮化鉭矽薄膜上的熱穩定性，最後採用RBS及歐傑電子能譜儀(AES)探討銅擴散之情形以及不同成份之Ta-Si-N薄膜對於銅於高溫擴散情形之比較。
實驗結果第一部分顯示，本實驗可利用控制鉭靶及矽靶功率來製作出9種不同成分的Ta-Si-N非晶質薄膜，分別命名為A1~A3、B1~B3、C1~C3。其中Ta/Si的比例為A > B > C 而N含量為3 > 2 > 1。所有薄膜之電阻率及化學鍵結皆具有高溫之熱穩定性。Ta-Si-N中各元素之作用分別為增加Si原子將會增進其非晶質態的程度、增加Ta原子將有助於降低電阻率及增加密度值，而增加N原子則可提高其結晶溫度。
從實驗結果第二部分中我們可以看出當Cu在Ta53Si3N44 (A2)、Ta53Si11N36 (B2)這兩組系統上時，幾乎沒有擴散的情形產生且片電阻在900℃退火後只上升些許。而Ta57Si5N38 (A1), Ta56Si12N32 (B1)這兩組系統中Ta的含量過高，因此可能有部分的Ta沒有和Si或是N鍵結住而容易擴散出Cu，導致Cu因此擴散進入Ta-Si-N。相反的在C組中Ta的含量非常低，當Ta量過少且N含量很高時，Ta-Si-N會是一個比較鬆散的結構進而造成Cu容易擴散進去。因此Ta-Si-N的成份會是影響當作阻障層好壞的因素且也會影響結晶的溫度。但是Ta-Si-N是否結晶並不是造成Cu和Ta-Si-N間是否會交互擴散的主因。

Ta-N based diffusion barrier has been used widely in copper interconnection system in IC. However, Ta-N films are mostly polycrystalline and the grain boundaries will serve as expedient diffusion paths. To overcome this problem, amorphous thin films of Ta-Si-N alloys were developed. We expect these alloys be a good structure to resist copper diffusion since their microstructures are free of grain boundaries.
In the first experiment, Ta-Si-N thin films were prepared by co-sputtering from Ta and Si targets, in an Ar+N2 atmosphere. The composition, resistivity, crystallographic structure and chemical bonding configuration were investigated by using Rutherford backscattering spectrometry(RBS), four-point probe, glancing incident angle X-ray diffraction(GIAXRD) and X-ray photoelectron spectroscopy(XPS).
In the second experiment, Ta-Si-N films of various compositions were applied as the diffusion barriers in Cu-SiO2 metallization system. Cu/Ta-Si-N/Ta/SiO2 samples were annealed in vacuum (2×10-5 Torr) at temperature ranging from 500 to 900oC for 30 min. The sheet resistance of Cu/Ta-Si-N/Ta/SiO2 samples, before and after annealing, was measured with a four-point probe. Compositional depth profiles of Cu/Ta-Si-N/Ta/SiO2 structures were analyzed with RBS and Auger electron spectroscopy(AES). Surface morphology of the samples was characterized using scanning electron microscopy (SEM). The characteristic phases were identified using glancing incident angle x-ray diffraction (GIAXRD).
From the first experiment, nine Ta-Si-N films of different compositions were fabricated. They are named as A1~A3, B1~B3, and C1~C3. Where the Ta/Si ratio is A > B > C, and the N content is 3 > 2 > 1. It is found that all Ta-Si-N films exhibit amorphous structures, and the degree of amorphism is enhanced when the Si ratio increases. All Ta-Si-N films show good thermal stability in their resistivity and chemical bonding configuration. Since Ta is a metallic element, high Ta content shall promote the conductivity and higher N content will increase the crystallization temperature of Ta-Si-N.
From the second experimet, the system with the Ta53Si3N44 (A2), Ta53Si11N36 (B2) barriers exhibits almost no intermixing between Cu and Ta-Si-N and it shows a minimum increase of sheet resistance after annealing at 900 oC. The system of the Ta57Si5N38 (A1), Ta56Si12N32 (B1) barriers with high Ta content and low N content, some of the Ta atoms may not bond with Si and N atoms so that they are free to diffuse across the Cu layer and some Cu atoms consequently diffuse into Ta-Si-N. On the contrary, group C barriers has a rather low Ta concentration. If the Ta content is too low and the N content is too high, the atomic arrangement of Ta-Si-N will become less closely packed and Cu atoms may penetrate into Ta-Si-N easily. Therefore, an adequate composition is critical for the barrier behavior of Ta-Si-N. Composition of Ta-Si-N may also determine the crystallization temperature. However, crystallization of Ta-Si-N does not directly relate with the interdiffusion between Cu and Ta-Si-N.

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