Microstructure Analysis and Device Characterization of Oriented Attachment-Assisted Growth SnS2 Nanoflakes via Chemical Vapor Deposition Method

• Main Authors: Yu-Kai Wu, 吳彧愷
• Other Authors: Chiu-Yen Wang
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/sezrxh

碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 105 === The oriented attachment (OA) of aggregated molecular clusters and nanoparticles have been discovered in solutions for many nanomaterials. However, it has not been reported in vapor phase deposition system. We quenched a series of products by co-evaporation of tin and sulfur in the growth stages and found tin dioxide was first formed polycrystalline of hexagonal nanoflakes with lateral size of 10 μm. After extending the time of furnace cooling, the sulfur content in nanoflakes were increasing until the tin dioxide nanoflakes were totally transformed into single crystalline SnS2. We performed high-resolution transmission electron microscope and found SnO2-rich and SnS2-rich areas coexisted in the intermediate stage which proved the SnO2 is directly transformed into SnS2 instead of non-stoichiometry compound. Fast Fourier transform (FFT) and selected area electron diffraction (SAED) patterns also helped to confirm the OA mechanism with the epitaxial relationship of (110)SnO2//(100)SnS2 and [001]SnO2//[001]SnS2. Moreover, the growth modes was also probed by adjusting amount of source and locations of substrate in synthesis procedures. The observed spiral growth agreed with the existence of screw dislocations which induced from OA mechanism.