Insulator-to-Metal Transition in Selenium-Hyperdoped Silicon: Observation and Origin

Abstract

Hyperdoping has emerged as a promising method for designing semiconductors with unique optical and electronic properties, although such properties currently lack a clear microscopic explanation. Combining computational and experimental evidence, we probe the origin of sub-band gap optical absorption and metallicity in Se-hyperdoped Si. We show that sub-band gap absorption arises from direct defect-to-conduction band transitions rather than free carrier absorption. Density functional theory predicts the Se-induced insulator-to-metal transition arises from merging of defect and conduction bands, at a concentration in excellent agreement with experiment. Quantum Monte Carlo calculations confirm the critical concentration, demonstrate that correlation is important to describing the transition accurately, and suggest that it is a classic impurity-driven Mott transition.

5 pages, 3 figures (PRL formatted)

Cited by in corpus (17)

• Breaking the doping limit in silicon by deep impurities
• Extended Infrared Photoresponse in Te-Hyperdoped Si at Room Temperature
• Nonradiative lifetimes in intermediate band materials - absence of lifetime recovery
• Hyperdoping silicon with selenium: solid vs. liquid phase epitaxy
• Structural Stability and Defect Energetics of ZnO from Diffusion Quantum Monte Carlo
• Towards a systematic assessment of errors in diffusion Monte Carlo calculations of semiconductors: case study of zinc selenide and zinc oxide
• Diffusion quantum Monte Carlo calculations of SrFeO${}_3$ and LaFeO${}_3$
• Thermal stability of Te-hyperdoped Si: Atomic-scale correlation of the structural, electrical and optical properties
• Micro-Raman spectroscopy of ultrashort laser induced microexplosion sites in silicon
• Suppressing the cellular breakdown in silicon supersaturated with titanium
• Possible atomic structures for the sub-bandgap absorption of chalcogen hyperdoped silicon
• Critical behavior of the insulator-to-metal transition in Te-hyperdoped Si
• Realizing the insulator-to-metal transition in Se-hyperdoped Si via non-equilibrium material processing
• Optical and electrical properties of textured sulfur hyperdoped silicon: a thermal annealing study
• How to modify the van der Waals and Casimir forces without change of dielectric permittivity
• Active Sites of Te-hyperdoped Silicon by Hard X-ray Photoelectron Spectroscopy
• Local Coordination Modulates the Reflectivity of Liquefied Si-Ge Alloys