Acceptor and compensating donor doping of single crystalline SnO (001) films grown by molecular beam epitaxy and its perspectives for optoelectronics and gas-sensing

Abstract

(La and Ga)-doped tin monoxide (stannous oxide, tin (II) oxide, SnO) thin films were grown by plasma-assisted and suboxide molecular beam epitaxy with dopant concentrations ranging from $\approx 5\times 10^{18}$cm${}^{-3}$ to $2\times 10^{21}$cm${}^{-3}$. In this concentration range, the incorporation of Ga into SnO was limited by the formation of secondary phases observed at $1.2\times 10^{21}$cm${}^{-3}$ Ga, while the incorporation of La showed a lower solubility limit. Transport measurements on the doped samples reveal that Ga acts as an acceptor and La as a compensating donor. While Ga doping led to an increase of the hole concentration from $1\times 10^{18}$cm${}^{-3}-1\times 10^{19}$cm${}^{-3}$ for unintentionally (UID) SnO up to $5\times 10^{19}$cm${}^{-3}$, La-concentrations well in excess of the UID acceptor concentration resulted in semi-insulating films without detectable $n$-type conductivity. Ab-initio calculations qualitatively agree with our dopant assignment of Ga and La, and further predict In${}_{\text{Sn}}$ to act as an acceptor as well as Al${}_{\text{Sn}}$ and B${}_{\text{Sn}}$ as donor. These results show the possibilities of controlling the hole concentration in $p$-type SnO, which can be useful for a range of optoelectronic and gas-sensing applications.

6 pages, 5 figures

References in corpus (5)

• SnO/$\beta$-Ga2O3 vertical $pn$ heterojunction diodes
• Adsorption-Controlled Growth of Ga2O3 by Suboxide Molecular-Beam Epitaxy
• Plasma-assisted molecular beam epitaxy of SnO(001) films: Metastability, hole transport properties, Seebeck coefficient, and effective hole mass
• Drastically enhanced cation incorporation in the epitaxy of oxides due to formation and evaporation of suboxides from elemental sources
• Epitaxial synthesis of unintentionally doped p-type SnO (001) via suboxide molecular beam epitaxy

Cited by in corpus (1)

• van der Waals epitaxy of lead monoxide - PbO and application as a virtual substrate for oxide membranes