Weak localization thickness measurements of embedded phosphorus delta layers in silicon produced by PH3 dosing

Published

January 23, 2018

Author(s)

Joseph A. Hagmann, Xiqiao Wang, Pradeep N. Namboodiri, Jonathan E. Wyrick, Roy E. Murray, Michael D. Stewart, Richard M. Silver

Abstract

The key building blocks for devices based on the deterministic placement of dopants in silicon are the formation of phosphorus dopant monolayers and the overgrowth of high quality crystalline Si. Lithographically defined dopant delta-layers can be formed with a scanning tunnel microscope, which can pattern device features on a hydrogen-terminated silicon surface by exposing Si dangling bonds at specific locations and implanting phosphorus at these locations with atomic precision. We investigate bulk samples to advance atomistic dopant placement and overgrowth processes necessary to produce prototypical few-atom devices in a controlled solid-state environment. The structure of the samples is determined from a suite of measurements that includes transmission electron microscopy, secondary ion mass spectrometry, and variable-temperature magnetotransport. We examine the effect of delta layer confinement on the weak localization observed in these samples at low temperatures and low magnetic fields. The parameters extracted from the fit of the weak localization feature to the Hikami-Larkin- Nagaoka equation demonstrate a method to test the above aspects of sample synthesis through electrical transport. Our results show that a 15 monolayer locking layer dramatically reduces the segregation of P during Si overgrowth. Our meticulous analysis serves as detailed instruction for the nondestructive determination of Si:P delta layer thickness.

Citation

Physical Review Applied

Pub Type

Journals

Keywords

single dopant devices, quantum computing, quantum information, weak localization, nanoelectronics, silicon

Citation

Hagmann, J. , Wang, X. , Namboodiri, P. , Wyrick, J. , Murray, R. , Stewart, M. and Silver, R. (2018), Weak localization thickness measurements of embedded phosphorus delta layers in silicon produced by PH3 dosing, Physical Review Applied (Accessed April 26, 2024)