Density-Functional Theory Study of Hydrogen Induced Platelets (HIPs) in Silicon

TL;DR

This study uses Density-Functional Theory to investigate the atomic structure and stability of hydrogen-induced platelets in silicon, revealing the most stable configurations and their energetic properties.

Contribution

It provides new insights into the atomic arrangements and stability of hydrogen-induced platelets in silicon using DFT calculations.

Findings

SiH2 is the most stable configuration in the (100) plane.

Planar hydrogen arrangements are unstable without Si bond breaking.

Certain hydrogen configurations (SiH3) are more stable than hydrogen in bulk silicon.

Abstract

In this contribution we present the results of Density-Functional Theory (DFT) calculations of platelets as modelled by infinite planar arrangements of hydrogen atoms and vacancies in (100) planes of silicon. From the observation of the relaxed platelet structures and the comparison of their energy with the one of hydrogen molecules dissolved in silicon we were able to evidence several features. A planar arrangement of hydrogen atoms inserted in the middle of Si-Si bonds proves unstable and Si bonds must be broken for the platelet to be stable. In the (100) plane the most stable configuration is the one with two Si-H bonds (a so-called SiH2 structure). It is possible to generate SiH3 structures which are more stable than hydrogen dissolved in Si bulk but less than SiH2 structures but SiH1 or SiH4 sometimes observed in experiments prove unstable.