The boron-hydrogen-phosphorus tri-elements co-doped stable N-type single crystalline Diamond

TL;DR

This paper reports a novel boron-hydrogen-phosphorus co-doping method for stable n-type single-crystal diamond, achieving high electron concentration, shallow donor levels, and strong UV emission, advancing diamond electronics.

Contribution

Introduces a precise tri-element co-doping strategy enabling stable n-type diamond with high conductivity and UV emission, surpassing previous doping limitations.

Findings

Electron concentration up to 1.0×10^19 cm^-3 achieved.

Donor level is shallow at approximately 61.6 meV.

Diamond exhibits strong UV emission with 69.4% internal quantum efficiency.

Abstract

Diamond is an outstanding semiconductor for extreme electronics, yet reproducible n-type doping remains a long-standing challenge. Here we demonstrate stable n-type single-crystal diamond grown in a single step by a precisely controlled boron-hydrogen-phosphorus co-doping strategy. Hall measurements yield electron concentrations up to 1.0*1019 cm-3 with a resistivity as low as 0.249 ohmic.cm. Secondary-ion mass spectrometry shows that tri-elements doping is the key for achieving n-type conductivity as the electron density exceeds the incorporated phosphorus concentration and is the same level of that of hydrogen and boron concentrations, supporting a donor mechanism beyond an isolated substitutional phosphorus or just boron-hydrogen co-doping. Temperature-dependent photoluminescence (PL) reveals this tri-elements codoping method induces the impurity band, and the donor level is quite shallow around 61.6 meV, consistent with the temperature dependent resistance measurements. Moreover, the co-doped diamond also exhibits strong ultraviolet emission near 270-285 nm, and the internal quantum efficiency is estimated to be 69.4%, while the undoped diamond or only boron doped diamond shows negligible UV emission. These results establish a practical route to low-resistance high luminous n-type diamond and its based chips.