First-principles calculations to investigate electronic structures and optical properties of chalcogens-hyperdoped silicon. (1st February 2022)

• Record Type: Journal Article
• Authors: Du, Lingyan; Yin, Jie; Zeng, Wei; Yi, Hao
• Is Part Of: Solid state communications. Volume 342(2022)
• Publication Date: 2022-02-01
• Subjects: First principle -- Chalcogens doped silicon -- Electronic structure -- Optical properties; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2021.114610
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: The properties of chalcogens doped silicon with different atomic structures are systematically investigated using first-principles. The calculated results show that substitutional structure exhibit best thermal stability and hexagonal interstitial is metastable structure. All configurations can introduce intermediate-band (IB) related to the impurity and lead to the below-band-gap absorption. Combining the optical properties with the formation energy calculations, we infer the high concentration of substitutional doping in Te-doped silicon prepared by fs-irradiating Si surface in the presence of chalcogens thin film will lead to it is more resistant to thermal annealing than S- and Se-doped Si as observed in experiments. Highlights: We designed four typical structural configurations of chalcogen doped in silicon, which include substitutional, two-fold coordinated interstitial, tetrahedral interstitial and hexagonal interstitial configurations, and investigated the geometries, electronic structures and optical properties of chalcogen-doped silicon in different configurations. The results of formation energy calculations show that the substitutional structure still gives the lowest energy among these structures for all chalcogen-doped Si samples. The electronic and optical properties calculations show that all configurations can introduce impurity band into the Si band gap and make contribution to the below-band-gap absorption.