Atomically precise dopant arrays in Si are being pursued for solid-state quantum computing applications. We propose a guided self-assembly process to produce atomically precise arrays of single dopant atoms in lieu of lithographic patterning. We leverage the self-assembled c(4x2) structure formed on Br- and I-Si(100) and investigate molecular precursor adsorption into the generated array of single-dimer window (SDW) adsorption sites with density functional theory (DFT). The adsorption of several technologically relevant dopant precursors (PH3, BCl3, AlCl3, GaCl3) into SDWs formed with various resists (H, Cl, Br, I) are explored to identify the effects of steric interactions. PH3 adsorbed without barrier on all resists studied, while BCl3 exhibited the largest adsorption barrier, 0.34 eV, with an I resist. Dense arrays of AlCl3 were found to form within experimentally realizable conditions demonstrating the potential for the proposed use of guided self-assembly for atomically precise fabrication of dopant-based devices.
@article{arxiv.2106.10556,
title = {Dopant Precursor Adsorption into Single-Dimer Windows: Towards Guided Self-Assembly of Dopant Arrays on Si(100)},
author = {Matthew S. Radue and Yifei Mo and R. E. Butera},
journal= {arXiv preprint arXiv:2106.10556},
year = {2022}
}