直流式磁控濺鍍系統鍍製鋯及鋯基氮化物薄膜之探討

Study of Zr and Zr-nitride Thin Films by DC Magnetron Sputtering

楊恆傑(Heng-Ghieh Yang) ； 劉全璞(Chuan-Pu Liu)

《鑛冶：中國鑛冶工程學會會刊》 46卷4期 (2002/12) Pp. 137-142

https://doi.org/10.30069/MM.200212_46(4).0011

摘要

為學習ULSI（Ultra Large Scale Integrated Cirecuits）製程中，矽與阻障層薄膜間的接面電性與結構問題，本研究以直流式磁控濺鍍系統鍍製鋯及鋯基氮化物薄膜（Zr & ZrNx Film）於n型（100）矽基材上，且利用X光繞射分析薄膜成相結構、α-Step薄膜厚度量測儀量測薄膜厚度，並以四點控針量測薄膜之片電阻值，掃瞄式電子顯微鋅觀察薄膜表面型態，能量散佈光譜儀分析薄膜雜質元素成分。實驗中改變濺鍍功率、濺鍍距離、基板偏壓、反應氮氣比率等製程參數，以探討並尋找較佳之鋯及鋯基氮化物薄膜結構與電性的鍍膜條件。研究結果顯示：1.鋯金屬薄膜的沈積速率、薄膜電阻率及氧元素含量，隨著基板負偏壓的增加呈現下降的趨勢，且薄膜之電性均勻性與結晶性亦隨之改善，晶體結構之優遠方位由Zr（002）逐漸轉變為較強的Zr（100）（002）（101）。2.鋯基氮化物薄膜的電阻率及氮－鋯元素成分比例，隨著濺鍍速率與反應氮氣比率而改變。欲鍍製稔合氮－鋯原子整數比的低電阻率氮化鋯（ZrN）薄膜，於高濺鍍速率條件下，可控制在較高與範圍較廣的反應氮氣比率；反之，於低測鍍速率時，將限制反應氮氣比率於較低及較小的控制範圍。現階段以直流式磁控測鍍系統製備於n型（100）矽基材上之鋯金屬薄膜，控制電源功率於80W、基板偏壓於－120～－140V，可得鋯薄膜電阻率約達95～115μΩ cm。另外，經由適當之反應氮氣比率及濺鍍速率參數之搭配，可製得薄膜電阻率達約114μΩ cm之氮化鋯薄膜。

關鍵字

測鍍系統 ； 擴散阻障層 ； 鋯 ； 氮化鋯 ； 鉭 ； 氮化鉭

並列摘要

To learn the properties of contact resistance and interface microstructure between Si and diffusion barriers in the ULSI processing, Zr and ZrN_x, thin films are deposited on n-type Si(001) substrates by DC magnetron sputtering in this study. The phases of the thin films are characterized by X-ray diffraction; film thickness is measured by a-step; film resistivity is measured by 4-point probe; film morphology is observed by SEM and film composition is determined by EDS. During deposition, applied power, target-to-substrate distance, substrate bias and N_2/Ar ratio in carrier gas are varied to explore and optimize the film properties in terms of its resistivity and microstructure. It is shown that the deposition rate, film resistivity and oxygen content of Zr thin films decrease as the substrate bias becomes more negative. The cystallinity and uniformity in film resistivity are also improved. In addition, the (002) preferred orientation gradually changes to (100) (002) (101) textures. As for the ZrN_x thin films, the film resistivity and its composition depend on deposition rate and N_2/Ar ratio. Under the high deposition rate condition, the stoichiometry ZrN of low resistivity phase can be obtained at the N_2/Ar ratio of wider range and higher value compared with the low deposition rate. The best resistivity of both Zr and ZrN_x thin films so far obtained are 95-115 μΩ cm using power 80W, the substrate bias of -120 ~ -140 V and 114 μΩ cm at the optimum condition, respectively.

並列關鍵字

Sputtering System ； Diffusion Barrier ； Zr ； ZrN Ta ； TaNx