中文摘要

本實驗主要研究目標為利用DC磁控濺鍍系統濺鍍鈷薄膜於(100)矽基板上並探討沉積的鈷薄膜是否可應用於OME製程上。固定濺鍍功率50Watt，工作壓力8x10-3torr，改變靶材到基板濺鍍距離(6，10及12cm)與基板偏壓，然後將所沉積的鈷薄膜進行膜厚及片電阻的電性量測，XRD分析，觀察薄膜結構變化，再利用場發射掃描式電鏡(FE-SEM)觀察薄膜的表面型態，最後製作鈷薄膜TEM試片，確定鈷膜的結構。另外，將幾組具有比較突出性質 (結晶性、平整性) 的鈷薄膜進行OME製程，由實驗得知：不同的濺鍍距離，對沉積鈷薄膜會產生不同的結構，濺鍍距離(Ds-t)6cm，工作壓力8x10-3torr，基板偏壓-100V，可以得到HCP結構的鈷薄膜，當濺鍍距離(Ds-t)10cm，工作壓力8x10-3torr，基板偏壓-100V，從TEM 繞射圖分析得知鈷薄膜的結構會轉變為FCC結構。濺鍍距離(Ds-t)6cm，基板偏壓-75V，工作壓力8x10-3torr的濺鍍條件可以沉積出最低電阻值(9.8μΩ-cm)的鈷薄膜，與鈷薄膜的理想電阻值8μΩ-cm相當接近。當濺鍍距離(Ds-t)10cm，基板偏壓-100V時，由AFM影像分析可得最佳薄膜平整性(Rms=0.864 nm)。
本論文的另一研究重點，即是利用DC磁控濺鍍系統進行OME製程。利用前半段鍍膜實驗可以得到最佳結晶性與平整性的鈷膜，應用此濺鍍參數沉積鈷薄膜，進行OME製程的前置鍍膜製程。使用雷射曲率掃描實驗，可以得知OME製程在400℃及650℃產生反應，將試片進行400℃及650℃退火，再對試片做XPS分析，從分析結果中，選擇有鈷元素反應的試片，再做低略角XRD以分析試片的結構，用AES分析試片的縱深反應，得知矽、氧及鈷原子在試片的相對關係，最後利用TEM截面分析確定產生磊晶矽化物。

Abstract

The primary aim of the research is to deposite Co thin films on Si(100) substrate by DC sputter system and study the viability of the applications in OME process. During seposition, power supply and working pressure are kept constant at 50 watt and 8x10-3 torr, respectively, while target to substrate distance and substrate bias are varied. Then we use α-step and four-point probe to measure the thickness and the sheet resistance of the sputtered films. We make use of XRD and FE-SEM to analyze the phases and morphologies of the specimens. Finally, we identify the microstructure of specimens by TEM analysis. According to the experimental results, we find that different deposition distance produces different cobalt structure. When deposition distance of 6 cm, working pressure of 8x10-3 torr, the bias of subatrate of -100 volt are applied, we could obtain Co thin film with HCP structure. If we change the deposition distance to 10 cm keeping the other parameters the same, the Co thin films of FCC structure can be obtained by TEM diffraction patterns. The lowest resistivity of Co thin film is 9.8 μΩ-cm obtained under the deposition distance of 6 cm, the structure bias of -100 volt, the working pressure of 8x10-3 torr, compared to 8 μΩ-cm from the ideal value of Co thin film. When the deposition distance of 10 cm, the subatrate bias of -100 volt, working pressure of 8x10-3 torr, are applied AFM image show that Co thin film is the smoothest, which is deposited by DC sputter system. In the research of the application of Co thin film in the OME process, the Co thin film are chosen to possess either the lowest resistivity or the smoothest parameter. From the continuous in-situ curvature measurement with temperature by a Laser beam, the reaction temperatures where chemical reactions possibly seriously occur are of 400℃ and 650℃, the chemical reactions including the chemical species redistribution and new phase formation are analyzed by XPS, GIXRD, AES, and XTEM. Ultimately, the epitaxial cobalt silicide is demonstrated to be successful in this study.

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