High Quality Transferable AlN Thin Film by PLD

33rd International Conference on the Physics of Semiconductors

Li, Heng^1 ; Lu, Xiaoli^1 ; Li, Xin^1 ; Zhang, Jincheng^1 ; Hao, Yue^1

Wide Band Gap Semiconductor Technology Discipline State Key Laboratory, School of Microelectronics, Xidian University, Xi'an

710071, China^1

关键词: C-plane sapphire substrates;    Clamping effects;    Crystalline quality;    High sensitivity;    Lattice-mismatched substrates;    Structural defect;    Wet chemical process;    ZnO buffer layer;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/864/1/012011/pdf
DOI  :  10.1088/1742-6596/864/1/012011

来源: IOP

【 摘 要 】

AlN thin film was epitaxial grown on c-plane sapphire substrate by pulsed laser deposition. To reduce structural defects from largely lattice mismatched substrate, MgO or ZnO buffer layer was inserted between AlN and sapphire. Crystal structure and surface morphology of as prepared AlN were characterized by XRD, AFM, and SEM. It was found that buffer layers significantly improve crystalline quality of AlN, especially using ZnO. Furthermore, a general and steady wet chemical process was developed to selectively etch away ZnO layer, so that high quality free-standing AlN thin film was obtained. This film could be transferred onto any other host substrates such as Si, quartz, etc. Moreover, with no clamping effect from the substrate, the as-prepared free-standing AlN thin films may find potential applications in high sensitivity piezoelectric devices, flexible wearable detectors and so on.