摘要
CsPbBr_(3)晶体因高原子序数、优异的载流子输运性能及室温工作特性,成为新一代半导体辐射探测器的核心候选材料。然而,晶体中的缺陷(如点缺陷、孪晶、夹杂相)会显著影响其性能。本综述系统分析了CsPbBr_(3)中缺陷的形成机制及其对载流子传输的制约:晶格极化子效应主导本征散射,点缺陷(如Pb间隙原子)通过深能级陷阱加剧载流子复合;铁弹畴(孪晶)因界面势垒导致载流子局域化;夹杂相(如CsPb_(2)Br_(5))通过光散射和非共格界面降低迁移率与电阻率。研究揭示了熔融法与溶液法生长动力学对缺陷分布的差异,并提出了化学计量调控、溶剂工程及退火工艺等优化策略。尽管CsPbBr_(3)在X/γ射线探测中展现出接近商用CZT的能谱分辨率(如1.4%@662 keV),但缺陷动态演化与离子迁移仍限制了其稳定性。未来需聚焦极化子-缺陷协同机制的分析、精准缺陷调控技术的开发及新型器件结构设计,以推动其在核医学成像、深空探测等领域的实际应用。
CsPbBr_(3) crystal has emerged as a promising candidate material for next-generation semiconductor radiation detectors due to its high atomic number,excellent charge transport properties,and room-temperature operability.However,defects in the crystal(point defects,twins,and secondary phases)significantly degrade its performance.This review systematically analyzes the formation mechanisms of defects in CsPbBr_(3) and their impact on carrier transport,lattice polaron effects dominate intrinsic scattering while point defects(e.g.,Pb interstitials)introduce deep-level traps that enhance carrier recombination,ferroelastic domains(twins)induce carrier localization through interfacial potential barriers,and secondary phases(e.g.,CsPb_(2)Br_(5))reduce mobility and resistivity via light scattering and incoherent interfaces.The study highlights differences in defect distribution between melt-and solution-grown crystals and proposes optimization strategies such as stoichiometric control,solvent engineering,and annealing.Although CsPbBr_(3) demonstrates X/γ-ray energy resolution comparable to commercial CdZnTe(e.g.,1.4%@662 keV),defect dynamics and ion migration hinder stability.Future research should focus on elucidating polaron-defect interactions,developing defect suppression techniques,and designing novel device architectures to advance its applications in nuclear medicine imaging and deep-space exploration.
作者
李宁
张欣雷
肖宝
张滨滨
LI Ning;ZHANG Xinlei;XIAO Bao;ZHANG Binbin(College of Advanced Interdisciplinary Studies&Nanhu Laser Laboratory,National University of Defense Technology,Changsha 410073,China;School of Physics and Information Technology,Shaanxi Normal University,Xi’an 710119,China;State Key Laboratory of Radiation Medicineand Protection,School for Radiological and Interdisciplinary Sciences(RAD-X),Soochow University,Suzhou 215123,China)
出处
《人工晶体学报》
北大核心
2025年第7期1146-1159,共14页
Journal of Synthetic Crystals
