Phosphorus‐Doped CdS Nanowires Showing n‐Type Behavior. Issue 10 (26th August 2018)

• Record Type: Journal Article
• Authors: Zeng, Yijie; Li, Song; Xie, Ruikuan; Huang, Yan; Lu, Aijiang; Fong, Ching Yao; Chen, Xiaoshuang; Xing, Huaizhong; Yao, Dao‐xin
• Is Part Of: Physica status solidi. Volume 255:Issue 10(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-08-26
• Subjects: CdS nanowires -- first‐principles calculations -- n‐type -- phosphorus doping; Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201800294
• Languages: English
• ISSNs: 0370-1972

Abstract

Abstract : Experimental work on phosphorus (P)‐doped cadmium sulfur (CdS) nanowires (NWs) shows unusual n ‐type electrical character, its physical origin is not well understood. Here this problem has been addressed by considering possible doping sites (interstitial, anion and cation sites), the distance of the doping site to NW surface, and the influence of dangling bond of host atoms. The P atom favors either a surface cation or a surface anion site, depending on the Cd chemical potential which reflects growth condition. At a surface anion site three p ‐type levels appear in the gap. On the other hand, at a surface cation site there is only one shallow n ‐type level in the gap, due to the s state of the P atom extending along the surface, as verified by both GGA and rough Meta‐GGA calculations. The physical origin of the n ‐type behavior for P‐doped CdS NWs is explained by assuming the P atom adopts the surface cation site, neglecting composite structure P atom forming with intrinsic defects. Abstract : In this article, a physical explanation is given of why phosphorus‐doped CdS nanowires show unusual n ‐type behavior. Calculations indicate that it is due to the phosphorus accumulating on the surface cation site, in this case a n ‐type donor level appears in the gap. Neither anion (or interstitial) site doping, nor surface cation dangling bond can cause the n ‐type behavior.