為了達成半導體技術微縮，源極/汲極應力源在先進技術節點中使用。在p型半導體中，硼是最廣泛使用的摻雜，因為好控制的擴散速度以及在矽中的高溶解度等，在現今科技中已是成熟的製程。將鍺與矽進行製程，使源極/汲極晶格常數增加，並且將壓應力轉換給通道，增強p型半導體通道載子遷移率。另一方面，可增加p型半導體的摻雜濃度，對降低串聯電阻有所助益。矽鍺中鍺的濃度對於調變鈦/硼摻雜之矽鍺之接觸電阻的特性需要再更進一步的研究，可以藉由可到達的最高摻雜活化濃度、晶格常數以及費米能階特性進行調變。在這份研究中，專注於在矽基底上以磊晶技術進行硼的矽鍺內摻雜，並應用於鈦/硼摻雜之矽鍺的電性接觸。這些機制對達成低接觸電阻係數的影響，量測萃取的方式為多環形傳輸線模型。這項探討是重要的，因為高的接觸電阻係數會限制微縮元件的特性。首先，探討應力對於硼摻雜之矽鍺的對接觸電阻係數的影響，控制鍺含量以及摻雜濃度一致，進行調變薄膜的厚度，實驗得到在硼摻雜之矽鍺有最大的應力情況，最佳的接觸電阻係數為5E-9 ·cm2。第二項實驗為金屬後退火對鈦矽鍺接觸電阻熱穩定性之研究，得知此項研究接觸電阻穩定性達到500 oC。此份研究對於邁進接觸電阻係數1E-9 ·cm2 的接觸特性了解及控制是重要的。

For the successful downscaling of semiconductor devices, source/drain stressors are used in modern technology nodes. In pMOS technologies, Boron is the most used dopant due its controllable diffusion depth and high solubility in Silicon, which is already mature in the processes nowadays. Alloying Si with Ge enlarges the source/drain material lattice parameter and allows to transfer compressive strain to the channel, resulting in enhanced carrier mobilities in pMOS devices. Moreover, it allows the achievement of high p-type doping concentrations, which is beneficial to reduce series resistance. As the Ge content in Si1-xGex modifies Ti / SiGe:B contact properties via the highest achievable active doping, SiGe:B lattice parameter, Fermi level pinning, it needs to be precisely chosen and tuned. In this study, focuses on Ti / SiGe:B contacts formed by using in situ doped SiGe:B epitaxially grown on Si. Mechanisms affecting the lowest achievable contact resistivity (ρc) using the multi-ring circular transmission line model technique are investigated. This is important since high ρc limit the performance of scaled devices. Firstly, discuss how strain in SiGe:B influences ρc by modulating the layer thickness while keeping the Ge content and doping concentration constant. The optimal conditions, providing ρc values of 5E-9 Ω.cm2, correlate with a maximal amount of strain in the SiGe:B. Secondly, the application of post metal annealing to further confirm the thermal stability of the fabricated contacts is investigated. The prepared contacts are stable up to 500oC. This study is an important step towards understanding and controlling contact properties in the low 1E-9 Ω.cm2 regime.

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