以奈米壓痕與穿透式電子顯微鏡分析氮化鋁鎵半導體薄膜之力學特性

Mechanical Characteristics of AIGaN Thin Films by Nanoindentation and Transmission Electron Microscopy

簡賸瑞(Sheng-Rui Jian) ； 林亭均(Ting-Chun Lin) ； 楊秉豐(Ping-Feng Yang) ； 賴逸少(Yi-Shao Lai) ； 莊振益(Jenh-Yih Juang)

《科儀新知》 181期 (2011/04) Pp. 68-74

https://doi.org/10.29662/IT.201104.0008

摘要

本研究結合奈米壓痕、聚焦離子來與穿透式電子顯微技術，探討氮化鋁鎵半導體薄膜在承受局部應力所導致之機械性質與變形機制。氮化鋁鎵薄膜以有機金屬氣相沉積法成長於氧化鋁基板上。奈米壓痕儀搭配連續性勁度量測系統，量測氮化鋁鎵薄膜之硬度與楊氏模數，其值分別為19.76±0.15 GPa與310.63±9.41 GPa。藉由聚焦離子束準確地定位壓痕位置並加以離子研磨，再搭配穿透式電子顯微鏡進行微結構觀察。實驗結果顯示：氮化鋁鎵薄膜因受局部應力所產生之結構變化特徵，主要之機制是錯位成核／傳遞導致滑移帶之形成。壓痕曲線之負載過程中有多個斷點或轉折現象，與錯位成核的機制所預期的相符。然而，壓痕曲線的卸載部分則無發現斷點或彎肘之現象，說明了氮化鋁鎵薄膜因奈米壓痕所導致之材料變形行為並不包含應力所引發之相變化現象。

並列摘要

This article reports a nanomechanical response study of the contact-induced deformation behavior in Alol6Ga0.84 thin film by means of a combination of nanoindentation and the cross-sectional transmission electron microscopy (XTEM) techniques. Alol6Ga0.84N thin film is deposited by using the metal-organic chemical vapor deposition (MOCVD) method. Hardness and Young's modulus of the Al0.16Ga0.84N films were measured by a Berkovich nanoindenter operated with the continuolls contact stiffness measurements (CSM) mode. The obtained values of the hardness and Young's modulus are 19.76±0.15 GPa and 310.63±9.41 GPa, respectively. The XTEM images taken in the vicinity regions just underneath the indenter tip revealed that the multiple ”pop-ins” observed in the load-displacement curve during loading are due primarily to the activities of dislocation nucleation and propagation The absence of discontinuities are in the unloading segments of load-displacement curve suggests that no pressure-induced phase transition was involved.