本研究以化學鍍成功的在二氧化矽表面沈積一層可同時作為銅內連線之擋層及晶種層用途之鎳鉬磷薄膜，並利用如電子顯微鏡(SEM)、Auger電子能譜儀(AES)、X光繞射(XRD)、四點探針及測厚儀等儀器量測鎳鉬磷薄膜之結構、鍍著速率、組成以及電阻率。藉由控制鉬酸根離子及鎳離子的比例、溫度、pH值，可得到各種不同組成的鎳鉬磷薄膜。其中，具奈米結構的Ni89Mo2P9 由於含磷量較高而具有較高的電阻率，而含磷量較低結晶性較強的Ni88Mo9P3則具有各組成中最低的電阻率。在鎳鉬磷薄膜上直接進行後續的電鍍銅以及藉由二次離子質譜儀的量測分別初步確認了鎳鉬磷作為銅擋層及晶種層的功能。在充滿氮氣的高溫爐中，我們分別在200, 300, 400,及500度的環境下，加熱多層結構的銅/鎳鉬磷/二氧化矽樣品並觀察銅原子在鎳鉬磷薄膜中的擴散行為。其中， Ni88Mo9P3 即使是與現行的氮化鈦相比，對於銅的擴散仍具有良好的阻障性質並且更在低電阻率上佔有優勢。這樣的結果證實經由化學鍍所製備的鎳鉬磷，確實能將擋層及晶種層的功能結合，再加上低成本的優勢而具有替代氮化鈦的潛力。此外，本研究亦開發出一種以電極修飾法(electrografting)接續於二氧化矽表面的聚乙烯口比 啶(poly 4-vinylpyridine, P4VP)為主體的化學鍍活化方式。即使在絕緣的二氧化矽基材上，仍然可以藉由一包含乙烯口比 啶(4-vinylpyridine, 4VP)單體之水相溶液進行電極修飾。P4VP的存在可藉由X光電子能譜儀(XPS)確認。將鍍有P4VP薄膜之二氧化矽樣品置於一包含鈀離子之水溶液中，可讓鈀離子包覆於P4VP中，並在不需要任何前處理之情形下，用以催化鎳鉬磷之化學鍍。此外，藉由某些元素在中的化學位移，可以確認P4VP與二氧化矽基材間Si-O-C之化學鍵以及Pd-P4VP錯合物的生成。以P4VP作為鎳鉬磷與二氧化矽基材間的介質，可有效改善鎳鉬磷之均勻度及附著性，並製備出相較於經由傳統鈀膠體所催化更薄的鍍層。藉由應用Pd-P4VP之活化法及其所催化的化學鍍鎳鉬磷擋層/晶種層，將可有效整合銅電鍍製程，並以濕式製程所具有之成本優勢，製造出積體電路的銅內連線結構。

A NiMoP film which may potentially be used as barrier/seed layer for Cu interconnect was successfully formed via electroless deposition atop SiO2. Four different wet processes were tried to activate the surface before electroless deposition. In addition, material properties including the crystal structure, deposition rate, composition and the electrical resistivity of NiMoP were investigated by scanning electron microscope (SEM), Auger electron microscope (AES), x-ray diffraction (XRD), 4-point probe, and surface profilometer (Alpha-step). NiMoP film of different compositions were obtained. Ni89Mo2P9 with nano-crystalline structure has the highest resistivity due to enriched P content while Ni88Mo9P3 has the lowest value among all. The seed layer and barrier layer functions of NiMoP were verified after Cu electrodeposition and the study of secondary ion mass spectroscopy (SIMS). Thermal cycles were then applied to Cu/NiMoP/SiO2 specimen in a nitrogen ambient at 200, 300, 400, and 500℃ respectively. Both the lattice and grain boundary diffusion of Cu in NiMoP was investigated by SIMS. The diffusion kinetics of each composition was discussed. Mo-rich Ni88Mo9P3 shows good barrier function in comparison with conventionally used TaN and possesses lower electrical resistivity. This finding indicates that NiMoP successfully combines the functions of seed layer and barrier layer, providing a potential alternative for conventional TaN/Cu seed couple. Next, a novel activator based on electrografting was developed for the electroless deposition of NiMoP. An aqueous solution containing 4-vinylpyridine (4VP) was prepared for electrografting of P4VP on SiO2/Si substrate despite the insulating property of the upper oxide layer. The identity and morphology of P4VP film was then investigated by X-ray Photoelectron Spectroscopy (XPS) and Scanning Probe Microscopy (SPM). In addition, when Pd ions were present in the solution, Pd was found to be incorporated within the electrografted P4VP matrix and could serve as an efficient activator for electroless deposition without further pretreatment. Moreover, the formation of Si-O-C bonding and Pd-P4VP complex were both confirmed by the chemical shift of several elements. The thickness control, uniformity and adhesion of the NiMoP deposit can all be improved by applying this novel activator. According to the result, a cost-effective all-wet process for fabricating Cu interconnect structure can thus be established by integrating Cu electrodeposition and electroless deposition of NiMoP with the aid of Pd-P4VP activator.

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