退火条件对Sn量子点生长和红外光学性质的影响

Effect of Annealing Conditions on the Morphology and Optical Properties of Sn Quantum Dots

首次采用固相外延生长技术在Si(001)表面直接生长Sn量子点,并应用原子力显微镜(AFM)、X射线衍射(XRD)和同步辐射傅里叶红外光谱(FTIR)研究了退火条件对量子点样品的表面形貌、结晶性和红外光学性质的影响。AFM结果表明,随着退火温度的升高和退火时间的延长,量子点的平均尺寸变大,面密度减小。XRD结果显示,外延得到的Sn量子点为四方结构的β-Sn,与衬底的相对取向为Sn(110)//Si(001)。由于β-Sn量子点的尺寸仍较大,同步辐射FTIR谱中没有观察到量子点的特征吸收峰。

Sn quantum dots（QDs） are directly deposited on Si（001） substrate by solid phase epitaxy for the first time. The effects of annealing conditions on the morphology, crystallinity and infrared absorption property of Sn QDs are investigated by atom force microscopy（AFM）, X-ray diffraction（XRD） and fourier transform infrared spectroscopy（FTIR）. AFM results show that either to increase annealing temperature or to prolong annealing time will lead to form larger Sn QDs with lower density. According to the XRD results, the formed Sn QDs are in tetragonal structure of β-Sn, with a distinct orientation on Si substrate of Sn（110）//Si（001）. Due to the large size of Sn QDs, its characteristic absorption peak is not observed from the synchrotron FTIR spectroscopy.