Simple physical model for the sign of the Hall coefficient in variable-range hopping conduction in heavily Al-doped p-type 4H-SiC. (3rd March 2021)

• Record Type: Journal Article
• Authors: Matsuura, Hideharu; Kondo, Yuki; Iida, Kosuke; Hidaka, Atsuki; Ji, Shiyang; Eto, Kazuma; Kojima, Kazutoshi; Kato, Tomohisa; Yoshida, Sadafumi; Okumura, Hajime
• Is Part Of: Japanese journal of applied physics. Volume 60:Number 3(2021)
• Publication Date: 2021-03-03
• Subjects: Heavily Al-doped 4H-SiC -- Hall coefficient -- Sign inversion of Hall coefficient -- Variable-range hopping conduction; Physics -- Periodicals; 621.05
• DOI: 10.35848/1347-4065/abe645
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: We observe negative Hall coefficients ( R H ( T )) in the variable-range hopping (VRH) conduction region for heavily Al-doped p-type 4H-SiC. We have proposed a simple physical model in which the difference between the density of hopping sites for holes and the density of hopping sites for electrons under a magnetic field determines the sign of R H ( T ), and explained the negative R H ( T ) in nearest-neighbor hopping (NNH) conduction. Based on our proposed model for NNH conduction, here we propose a model in which R H ( T ) becomes positive when the density of localized states ( g ( E )) around the Fermi level ( E F ) increases with increasing energy ( E ), whereas R H ( T ) becomes negative when g ( E ) around E F decreases with increasing E . In heavily Al-doped p-type 4H-SiC where g ( E ) around E F is considered to decrease with increasing E, the proposed model can explain why R H ( T ) becomes negative in the VRH conduction region.