正电子对固体中电子的密度和动量分布很敏感。研究正电子在固体中的湮没辐射谱,可以获得有关固体中缺陷态的电子结构的信息。目前用正电子谱学来研究半导体中的缺陷的工作主要是研究辐照诱生缺陷。无位错Si中的原生微缺陷对Si器件性能影响很大。用缀饰、X射线貌相及电子显微镜等常规方法观察,发现无位错Si中至少有三种微缺陷,即带状分布的A型及B型漩涡缺陷、非带状分布A型与B型缺陷(D缺陷)、以及更细微的第三种缺陷。但至今尚不能肯定的是:在热平衡条件下Si中,本征点缺陷,究竟是空位还是自间隙原子。对第三种缺陷,有人认为是空位团,而对空位团的性质则了解得非常少,因为它们还没有用电镜等方法直接观测到。文献一方面论证了第三种缺陷具有空位的某 Positrons are sensitive to the density and momentum distribution of electrons in solids. Studying the annihilation radiation spectrum of positrons in solids can provide information about the electronic structure of the defect states in solids. At present, the work of positron spectroscopy to study the defects in semiconductors is to study the irradiation-induced defects. The primary micro-defects in dislocated Si have a great influence on the performance of Si devices. By means of conventional methods such as embossing, X-ray topography and electron microscopy, it is found that there are at least three kinds of microdefects in the dislocation-free Si, that is, banded distribution of type A and type B vortex defects, non-banded distribution of type A and type B defects (D defects), and a finer third defect. But so far it is still not certain whether the intrinsic point defects in Si under thermal equilibrium conditions are vacancy or interstitial atoms. For the third defect, some consider vacancies, and very little about the nature of vacancies because they have not been directly observed by electron microscopy or other methods. On the one hand, the literature demonstrates that the third defect has some space