On the nature of large-scale defect accumulations in Czochralski-grown silicon

TL;DR

This paper investigates large-scale impurity accumulations in Czochralski-grown boron-doped silicon, revealing distinct formation mechanisms from float zone silicon and proposing a classification and model for these impurity structures.

Contribution

It introduces a new classification and a model for large-scale impurity accumulations in CZ-grown silicon, based on experimental analysis.

Findings

Impurity accumulations differ from float zone silicon clouds.

A classification scheme for impurity accumulations is proposed.

A model explaining the formation of these accumulations is presented.

Abstract

Czochralski-grown boron-doped silicon crystals were studied by the techniques of the low-angle mid-IR-light scattering and electron-beam-induced current. The large-scale accumulations of electrically-active impurities detected in this material were found to be different in their nature and formation mechanisms from the well-known impurity clouds in a float zone-grown silicon. A classifcation of the large-scale impurity accumulations in CZ Si:B is made and point centers constituting them are analyzed in this paper. A model of the large-scale impurity accumulations in CZ-grown Si:B is also proposed.