Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping

Device applications of ultra-wide bandgap diamond rely on controlled carrier types and concentrations, yet conventional n-type doping in diamond has been challenging due to its strong covalent bonds. Surface charge transfer doping (SCTD) provides an effective alternative, utilizing energy level diff...

Full description

Saved in:
Bibliographic Details
Main Authors: Defeng Liu, Guixuan Wu, Shulin Luo, Gangcheng Wang, Xiaowei Wang, Xueting Wang
Format: Article
Language:English
Published: AIP Publishing LLC 2024-12-01
Series:APL Materials
Online Access:http://dx.doi.org/10.1063/5.0245733
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850040019045056512
author Defeng Liu
Guixuan Wu
Shulin Luo
Gangcheng Wang
Xiaowei Wang
Xueting Wang
author_facet Defeng Liu
Guixuan Wu
Shulin Luo
Gangcheng Wang
Xiaowei Wang
Xueting Wang
author_sort Defeng Liu
collection DOAJ
description Device applications of ultra-wide bandgap diamond rely on controlled carrier types and concentrations, yet conventional n-type doping in diamond has been challenging due to its strong covalent bonds. Surface charge transfer doping (SCTD) provides an effective alternative, utilizing energy level differences between surface dopants and semiconductors to modulate carrier properties. In this study, we examined n-type SCTD doping on oxygen- and fluorine-passivated diamond (100) surfaces [diamond(100):Y, where Y = O, F] using alkali metals (Na, K, Rb, and Cs) through first-principle calculations. Following surface metal doping of diamond(100):Y, electron enrichment shifted the Fermi level into the conduction band, confirming effective n-type doping. The maximum areal electron densities reached 2.50 × 1014 cm−2 for diamond(100):O and 2.00 × 1014 cm−2 for diamond(100):F, exceeding the previously reported optimal values for surface organic molecule doping. For diamonds of equal thickness and identical passivating atoms, charge transfer followed the trend Na > K > Rb > Cs, inversely related to atomic radius. With increasing diamond thickness, charge transfer rose for oxygen-passivated surfaces and declined for fluorine-passivated ones before stabilizing, corresponding to the conduction band minimum (CBM) shift: downward for oxidization and upward for fluorination. For all alkali metal surface doping, charge transfer was greater in diamond(100):O than in diamond(100):F, owing to the lower CBM of oxidized diamond. Overall, effective n-type SCTD doping is critically influenced by diamond’s CBM levels—dependent on its thickness and surface passivation—and the metal atom’s radius. These findings provide theoretical insights into advancing diamond-based electronic and optoelectronic devices.
format Article
id doaj-art-c4a0151488c8406fb8dd131f37863a67
institution DOAJ
issn 2166-532X
language English
publishDate 2024-12-01
publisher AIP Publishing LLC
record_format Article
series APL Materials
spelling doaj-art-c4a0151488c8406fb8dd131f37863a672025-08-20T02:56:11ZengAIP Publishing LLCAPL Materials2166-532X2024-12-011212121118121118-910.1063/5.0245733Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal dopingDefeng Liu0Guixuan Wu1Shulin Luo2Gangcheng Wang3Xiaowei Wang4Xueting Wang5School of Physics Science and Information Technology, Liaocheng University, Liaocheng 252059, People’s Republic of ChinaState Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, People’s Republic of ChinaState Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, People’s Republic of ChinaState Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, People’s Republic of ChinaSchool of Physics Science and Information Technology, Liaocheng University, Liaocheng 252059, People’s Republic of ChinaSchool of Physics Science and Information Technology, Liaocheng University, Liaocheng 252059, People’s Republic of ChinaDevice applications of ultra-wide bandgap diamond rely on controlled carrier types and concentrations, yet conventional n-type doping in diamond has been challenging due to its strong covalent bonds. Surface charge transfer doping (SCTD) provides an effective alternative, utilizing energy level differences between surface dopants and semiconductors to modulate carrier properties. In this study, we examined n-type SCTD doping on oxygen- and fluorine-passivated diamond (100) surfaces [diamond(100):Y, where Y = O, F] using alkali metals (Na, K, Rb, and Cs) through first-principle calculations. Following surface metal doping of diamond(100):Y, electron enrichment shifted the Fermi level into the conduction band, confirming effective n-type doping. The maximum areal electron densities reached 2.50 × 1014 cm−2 for diamond(100):O and 2.00 × 1014 cm−2 for diamond(100):F, exceeding the previously reported optimal values for surface organic molecule doping. For diamonds of equal thickness and identical passivating atoms, charge transfer followed the trend Na > K > Rb > Cs, inversely related to atomic radius. With increasing diamond thickness, charge transfer rose for oxygen-passivated surfaces and declined for fluorine-passivated ones before stabilizing, corresponding to the conduction band minimum (CBM) shift: downward for oxidization and upward for fluorination. For all alkali metal surface doping, charge transfer was greater in diamond(100):O than in diamond(100):F, owing to the lower CBM of oxidized diamond. Overall, effective n-type SCTD doping is critically influenced by diamond’s CBM levels—dependent on its thickness and surface passivation—and the metal atom’s radius. These findings provide theoretical insights into advancing diamond-based electronic and optoelectronic devices.http://dx.doi.org/10.1063/5.0245733
spellingShingle Defeng Liu
Guixuan Wu
Shulin Luo
Gangcheng Wang
Xiaowei Wang
Xueting Wang
Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
APL Materials
title Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
title_full Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
title_fullStr Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
title_full_unstemmed Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
title_short Unlocking n-type semiconductivity in diamond: A breakthrough approach via surface metal doping
title_sort unlocking n type semiconductivity in diamond a breakthrough approach via surface metal doping
url http://dx.doi.org/10.1063/5.0245733
work_keys_str_mv AT defengliu unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping
AT guixuanwu unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping
AT shulinluo unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping
AT gangchengwang unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping
AT xiaoweiwang unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping
AT xuetingwang unlockingntypesemiconductivityindiamondabreakthroughapproachviasurfacemetaldoping