Defect structures and dopant solution states of Hf‐doped Si3N4 ceramics. Issue 1 (13th October 2022)

• Record Type: Journal Article
• Authors: Kuwabara, Akihide; Gao, Xiang; Riedel, Ralf; Ionescu, Emanuel; Ikuhara, Yuichi
• Is Part Of: International journal of applied ceramic technology. Volume 20:Issue 1(2023)
• Page Start: 190
• Page End: 196
• Publication Date: 2022-10-13
• Subjects: defects -- dopants/doping -- silicon nitride -- simulation; Ceramics -- Periodicals; Ceramics -- Technological innovations -- Periodicals; 620.1405
• DOI: 10.1111/ijac.14236
• Languages: English
• ISSNs: 1546-542X

Abstract

Abstract: Transition‐metal‐doped silicon nitride ceramics have attracted much attention as gate materials for semiconductors because of their electrical properties as well as chemical and thermal stability. The present study aims to clarify the defect structures of Hf‐doped β ‐Si3 N4 by theoretical calculations and scanning transmission electron microscopy (STEM). First‐principles calculations based on a hybrid functional method were performed. It was found that Hf dopants are mainly substituted for the Si sites and can be occasionally located at interstitial sites in the lattice of β ‐Si3 N4 . The substitution sites of Hf dopants predicted by the first‐principles calculations were also confirmed by the high‐resolution STEM images. Abstract : Optimized atomic configurations around (left) substitutional and (right) interstitial defects of Hf in β ‐Si3 N4, respectively.