以反應性脈衝磁控濺鍍製備氮化鋯薄膜與薄膜性質測定

Preparation and Characterization of ZrNχ Film Deposition Using the Pulsed Reactive Magnetron Sputtering

溫靖嫻(Ching-Hsien Wen)

指導教授 ： 吳和生

元智大學/工程學院/化學工程與材料科學學系/碩士(2006年)

摘要

本研究是以p-type (100)矽晶圓為基材，利用反應性脈衝磁控濺鍍系統沉積氮化鋯薄膜，在單極性(unipolar)負脈衝條件下，改變反應氣體(N2)流量來沉積薄膜，以對氮化鋯薄膜成長與其結構之影響進行探討。文中使用GIAXRD分析薄膜的結晶狀態、AES分析薄膜元素的化合物比、AFM分析表面粗糙度、FEG-SEM和alpha-step量測薄膜厚度、FEG-SEM觀察表面形態、四點探針量測不同氮氣流量比例的電阻率、半導體參數量測系統分析氮化鋯薄膜的C-V和I-V電性值等，以期能對氮化鋯薄膜的結構和特性作一徹底的瞭解。

實驗結果指出，氮化鋯薄膜的沉積速率在125~101 nm/min，是隨著氮氣流量的增加而下降，是較快於參考文獻內的沉積速率(文獻在60~11 nm/min，快約2~11倍)。同時，真空腔體中的壓力會對沉積速率有很大的影響。經GIAXRD確認，繞射峰強度皆隨著氮氣流量的增加而增加，顯示氮原子的增加是有助於結晶結構的形成，此趨勢與參考文獻相同。以脈衝濺鍍沉積的N/Zr元素化學計量比約為0.86~0.94，符合參考文獻內的範圍(文獻在0.8~1.3) ；在薄膜表面的粗糙度和電阻率與氮氣流量成正比，薄膜粗糙度與文獻比較，是屬於較平滑的薄膜；此脈衝濺鍍法所沉積的氮化鋯薄膜，依據參考文獻是屬於低介電材質(k = 3.6~2.5)薄膜，是頗佳的Cu/ZrNχ/Si障礙層之生成法。

關鍵字

反應性脈衝磁控濺鍍、氮化鋯、單極性負脈衝、

並列摘要

The deposited Zirconium-Nitride film on the substrate of a p-type (100) Si wafer has been investigated through pulsed-DC reactive magnetron sputtering. The characteristics and microstructure effects are surveyed by the various pulsing configurations (unipolar) and nitrogen gas flow rates. The detailed description for the analyzed equipments and methods are contained in this thesis, including grazing incidence X-ray diffraction (GIAXRD) to analyze the crystallized status; the Auger electron spectrometer (AES) to detect the chemical composition, the atomic force microscope (AFM) to measure the surface roughness, the field emission gun scanning electron microscope (FEG-SEM) and alpha-step tester to observe the surface and measure the thickness of thin films; the four-point probe to obtain the sheet resistance, and the semiconductor parameter analyzer to determine the electrical characterizations in capacitance-voltage (C-V) and current-voltage(I-V).

The results indicate that the different pulsing parameters affect the deposition rate of the Zirconium-Nitride film. The deposition rate is 125~101 nm/min for Zirconium-Nitride films, it is inverse proportion to the N2 flow rate. Comparing to the previous issues (60~11 nm/min), the depositing efficiency of pulsed plasma sputtering approaches about 2~11 times. The chamber pressure is one of important factors relative to depositing rates. There is the stable crystal orientation of the Zirconium-Nitride microstructure following the adding of N2 flows via GIAXRD identification, which is similar to the references. The composition ratio of Zr and N is actually around 0.86~0.94, similar to the literatures (0.8~1.3). The surface roughness and resistivity, proportional to N2 flows, have a better advantage compared to the description from other previous works. The surface characteristics of the ZrN layer pertain to fine grain and lower resistivity. Using the pulsed sputtering for zirconium nitride deposition, the experimental results demonstrate that the zirconium nitride film has low dielectric feature (k ＝3.6~2.5) with the excellent diffusion barrier among the Cu/ZrNχ/Si layer.

並列關鍵字

Reactively pulsed magnetron sputtering、Zirconium nitride、Unipolar-negative pulsing、Thin-film deposition、Dielectric material

參考文獻

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