高功率脈衝磁控濺鍍製程中離子轟擊對氮化鈦薄膜織構及性質之影響

Effect of ion bombardment on texture and properties of TiN thin films deposited by High Power Impulse Magnetron Sputtering

陳政揚

指導教授 ： 黃嘉宏 ； 喻冀平

國立清華大學/原子科學院/工程與系統科學系/碩士(2012年)

https://doi.org/10.6843/NTHU.2012.00658

摘要

本研究利用高功率脈衝磁控濺射系統(HIPIMS)將奈米晶氮化鈦薄膜鍍著於矽(100)基材上。研究目的在於探討離子轟擊對氮化鈦薄膜織構、機械性質及鍍膜速率的影響。實驗設計以調控氮氣流量(N系列)及基材偏壓(B系列)來控制離子轟擊的強度。X光繞射結果顯示，氮化鈦薄膜均以(220)為優選方向，此結果與以往的文獻資料不同，主因為離子通道效應所致。(220)織構係數與離子轟擊的程度有緊密的關係，此係數會隨著氮氣流量增加而上升，也會隨著基材偏壓由負轉正而下降。薄膜的鍍膜速率可經由掃描式電子顯微鏡量測膜厚推得。因薄膜再濺射的關係，N系列的鍍膜速率會隨著離子轟擊增加而線性下降；而B系列鍍膜速率下降之原因則為，隨著基板偏壓由負轉正，使得較少金屬離子受到基材所吸引所造成的。此外，實驗結果亦顯示，在HIPIMS系統中，離子轟擊會顯著的影響氮化鈦薄膜的電阻率及殘餘應力。隨著離子轟擊程度降低，兩系列的薄膜電阻率都會下降，同樣的，B系列殘餘壓應力也會隨著基板偏壓由負轉正而降低。而薄膜硬度值波動很小(介於21.7至25.9 GPa之間)，應該與晶界主導變形機制及薄膜堆積密度有關。

關鍵字

高功率脈衝磁控濺射 ； 氮化鈦 ； 織構 ； 硬度 ； 殘餘應力 ； 電阻率

並列摘要

Nano-crystalline TiN thin films were successfully deposited on (100) silicon substrate utilizing a high power impulse magnetron sputtering (HIPIMS) system. The purpose of this research was to investigate the effects of ion bombardment on the texture, mechanical properties, and the deposition rate of TiN thin films, where the extent of ion bombardment was controlled by varying nitrogen flow rates (N-series) and substrate bias (B-series). Unlike the texture reported in previous literatures, X-ray diffraction (XRD) revealed that most of the specimens possess (220) preferred orientation due to ion channeling effect. The (220) texture coefficient was closely related to the extent of ion bombardment, which may increase due to increasing nitrogen flow rate or decrease as the substrate bias switched from negative to positive. The film thickness was measured from cross-sectional SEM images where the deposition rate was obtained. Owing to ion re-sputtering, the deposition rate of N-series specimens decreased linearly with increasing ion bombardment. For the B-series specimens, the decrease of deposition rate is attributed to the fact that fewer metal ions were attracted to the substrate as the substrate bias switched from negative to positive. In addition, the results showed that the ion bombardment in HIPIMS significantly influenced the residual stress and electric resistivity of the TiN films. As the extent of ion bombardment decreased, the electric resistivity decreased in both series films and similarly the compressive residual stress of B series specimens decreased when the substrate bias switched from negative to positive. The small variation of hardness of the TiN films, ranging from 21.7 to 25.9 GPa, was correlated to the grain boundary-mediated deformation mechanisms and the packing density of the films.

並列關鍵字

HIPIMS ； TiN ； Texture ； Hardness ； Residual stress ； Resistivity

參考文獻

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