Interfacial Oxidation Enables Charge-Transfer Contacts and Degenerate n-Doping in Monolayer MoS$_2$
Fuente:
arXiv
Gespeichert in:
| Hauptverfasser: | , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Veröffentlicht: |
2026
|
| Schlagworte: | |
| Online-Zugang: | |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1866911473831247872 |
|---|---|
| author | Bianchi, Marco Lizzit, Daniel Turoldo, Alberto Tosi, Ezequiel Lacovig, Paolo Schied, Monika Curcio, Davide Sanders, Charlotte E. Lizzit, Silvano Hofmann, Philip |
| author_facet | Bianchi, Marco Lizzit, Daniel Turoldo, Alberto Tosi, Ezequiel Lacovig, Paolo Schied, Monika Curcio, Davide Sanders, Charlotte E. Lizzit, Silvano Hofmann, Philip |
| contents | High contact resistance remains a central obstacle to the integration of two-dimensional (2D) semiconductors in electronic devices. Recent advances have demonstrated that contact performance can be dramatically improved through interface engineering, including the use of group-V semimetals and charge-transfer contacts based on strong interfacial doping. Here, we show that controlled interfacial oxidation provides an effective route to convert a semimetal contact into a charge-transfer contact that degenerately $n$-dopes single layer MoS$_2$. Using a combination of angle-resolved photoemission spectroscopy, X-ray photoelectron diffraction, low-energy electron diffraction and scanning tunnelling spectroscopy, we demonstrate that putting single layer MoS$_2$ in contact with a pristine Bi layer merely results in weak doping, whereas oxidation of the Bi layer leads to a pronounced occupation of the MoS$_2$ conduction band with an electron density on the order of $10^{13}$~cm$^{-2}$. The cause of this strong electron doping is the fact that an ultrathin $β$-Bi$_2$O$_3$ layer forms below the MoS$_2$ and that this has a particularly low work function, thereby acting as an efficient electron donor to MoS$_2$. Interfacial oxidation thus emerges as a powerful design knob for engineering charge-transfer contacts to 2D semiconductors. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2602_24057 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | Interfacial Oxidation Enables Charge-Transfer Contacts and Degenerate n-Doping in Monolayer MoS$_2$ Bianchi, Marco Lizzit, Daniel Turoldo, Alberto Tosi, Ezequiel Lacovig, Paolo Schied, Monika Curcio, Davide Sanders, Charlotte E. Lizzit, Silvano Hofmann, Philip Materials Science High contact resistance remains a central obstacle to the integration of two-dimensional (2D) semiconductors in electronic devices. Recent advances have demonstrated that contact performance can be dramatically improved through interface engineering, including the use of group-V semimetals and charge-transfer contacts based on strong interfacial doping. Here, we show that controlled interfacial oxidation provides an effective route to convert a semimetal contact into a charge-transfer contact that degenerately $n$-dopes single layer MoS$_2$. Using a combination of angle-resolved photoemission spectroscopy, X-ray photoelectron diffraction, low-energy electron diffraction and scanning tunnelling spectroscopy, we demonstrate that putting single layer MoS$_2$ in contact with a pristine Bi layer merely results in weak doping, whereas oxidation of the Bi layer leads to a pronounced occupation of the MoS$_2$ conduction band with an electron density on the order of $10^{13}$~cm$^{-2}$. The cause of this strong electron doping is the fact that an ultrathin $β$-Bi$_2$O$_3$ layer forms below the MoS$_2$ and that this has a particularly low work function, thereby acting as an efficient electron donor to MoS$_2$. Interfacial oxidation thus emerges as a powerful design knob for engineering charge-transfer contacts to 2D semiconductors. |
| title | Interfacial Oxidation Enables Charge-Transfer Contacts and Degenerate n-Doping in Monolayer MoS$_2$ |
| topic | Materials Science |
| url | https://arxiv.org/abs/2602.24057 |