Ultra-dense phosphorus in germanium delta-doped layers

Abstract

Phosphorus (P) in germanium (Ge) delta-doped layers are fabricated in ultra-high vacuum by adsorption of phosphine molecules onto an atomically flat clean Ge(001) surface followed by thermal incorporation of P into the lattice and epitaxial Ge overgrowth by molecular beam epitaxy. Structural and electrical characterizations show that P atoms are confined, with minimal diffusion, into an ultra-narrow 2-nm-wide layer with an electrically-active sheet carrier concentration of 4x10^13 cm-2 at 4.2 K. These results open up the possibility of ultra-narrow source/drain regions with unprecedented carrier densities for Ge n-channel field effect transistors.

Cited by in corpus (7)

• Topological Insulators in Random Lattices
• Atomic-scale patterning of hydrogen terminated Ge(001) by scanning tunneling microscopy
• Electronic transport in two dimensional Si:P $\delta$-doped layers
• Influence of encapsulation temperature on Ge:P delta-doped layers
• Bottom-up assembly of metallic germanium
• Electronic properties of delta-doped phosphorus layers in silicon and germanium
• Atomic-layer doping of SiGe heterostructures for atomic-precision donor devices