Nanomechanical properties and deformation behavior of Ⅲ-Nitride compound semiconductor thin films gown by metal- organic chemical vapor deposition

• Main Authors: Chih-Yen Huang, 黃智彥
• Other Authors: Sheng-Rui Jian
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/dhergy

博士 === 義守大學 === 材料科學與工程學系 === 106 === In the present study, Mainly on the analysis of the nanamechanical properties of Mg-doped AlGaN and InN of the Group III nitride. The test piece was prepared on a sapphire substrate using Metal Organic Chemical Vapor Deposition(MOCVD). Applied X-ray Diffraction(XRD), Scanning Electron Microscopy(SEM), Atomic Force Microscope(AFM), Secondary Ion Mass Spectrometry(SIMS), Focused Ion Beam system(FIB), Transmission Electron Microscope(TEM), and nanoindentation techniques method performs test piece preparation, observation, and measurement. Measure the mechanical properties of the film (hardness and Young''s modulus) using nanoindentation tester with continuous stiffness measurement (CSM). It can be seen that as the Mg doping concentration increases, the hardness and Young''s model of AlGaN thim film tend to increase.It can be found that as the magnesium(Mg) doping concentration increases, both the hardness and the Young''s mode of the AlGaN film tend to increase. The flow rate of bis(cyclopentadienyl)magnesium(Cp2Mg) increases from 100 to 600 sccm, and Mg is doped. As the concentration increases, the AlGaN thin film hardness increases from 20.62±0.53 to 24.17±0.72GPa, and the Young''s modulus increases from 317.48±7.82 to 364.63±17.62GPa.The hardness and Young''s modulus of the InN thin film were also measured as 4.2±0.1GPa and 152.5±3.9GPa, respectively. From the load-displacement curve plot, the “pop-in” event due to local stress during the nanoindentation test is mainly due to the formation of slip bands caused by dislocation nucleation and propagation due to indenter loading. There are multiple break points or turning phenomena in the loading process of the indentation curve, which is consistent with the mechanism of nucleation of dislocations. However, no breakpoints or elbows were found in the unloaded part of the indentation curve, indicating that the deformation behavior of the film caused by the nanoindentation does not include the phase change induced by the stress.