InSb/HfO2堆栈在原位退火过程中利用同步辐射光电子能谱对元素扩散的研究

Elemental Diffusion Study of Insb/HfO2 Stacks upon in Situ Post Deposition Annealing by Synchrotron Radiation Photoemission Spectroscopy

InSb作为重要的Ⅲ-Ⅴ族半导体材料已经应用在光电探测器、中红外激光器等领域,但InSb与氧化物的界面质量对制造高性能器件仍然至关重要。通过对InSb/HfO2堆栈在300和400℃下原位退火来系统地研究其热稳定性。为了研究InSb/HfO2堆栈衬底元素的扩散,利用原子层沉积技术沉积了大约5nm厚的HfO2薄膜,通过光子能量为750和600eV的同步辐射光电子能谱来进行表征时只能探测到堆栈界面以上部分的元素信息。研究发现对HCl预处理和天然氧化样品,In氧化物的扩散分别发生在300和400℃退火后,Sb氧化物的扩散现象只在原子层沉积之后的HCl预处理样品上被发现。本工作强调了为提高InSb器件性能而对界面进行有效钝化的紧迫性。

InSb is an important III-V semiconductor material for various devices like photovoltaic detectors and mid infrared lasers.The quality of the interface between InSb and oxide is crucial to fabricate high performance devices.We have investigated the thermal stability of InSb/HfO 2 stacks upon in situ post deposition annealing(PDA)at 300 and 400℃.To study the elemental diffusion of the InSb/HfO 2 stack,a 5 nm HfO 2 film was grown by atomic layer deposition(ALD)which prevents the detection of interface signals by synchrotron radiation photoemission spectroscopy with the incident photon energy of 750 and 600 eV.The results indicate that the diffusion of indium oxide was observed on both HCl pretreated sample and native oxide sample after PDA at 300 and 400℃,respectively,while the diffusion of antimony oxide was only observed on the HCl pretreated sample after ALD process.This work highlights the urgency of suitable interface passivation for performance improvement of InSb.