Use of a thermal plasma process to recycle silicon kerf loss to solar-grade silicon feedstock

M. de Sousa; Armelle Vardelle; Gilles Mariaux; Michel Vardelle; U. Michon; V. Beudin

Use of a thermal plasma process to recycle silicon kerf loss to solar-grade silicon feedstock

M. de Sousa ¹ Armelle Vardelle ¹ Gilles Mariaux ¹ Michel Vardelle ¹ U. Michon ² V. Beudin ²

1 SPCTS-AXE2 - Axe 2 : procédés plasmas et lasers

SPCTS - Science des Procédés Céramiques et de Traitements de Surface

2 SILIMELT

Abstract : The objective of this study was to recycle the dust generated in the slicing of silicon wafers (silicon kerf) by means of a two-stage thermal plasma process. In the first stage, the silicon particles are injected in a plasma jet where silicon oxides and carbon impurities are removed by vaporization. In the second stage, the purified silicon droplets are collected in a silicon bath maintained in a hot-wall crucible. The optimal operating conditions for reduction were determined by injecting into the plasma jet a commercial silicon powder of known degree of oxidation and measuring the attained degree of reduction. Also, silicon powders from wafer slicing were processed in the two-stage plasma set-up. The results of these tests showed that the deoxidation rate of the final silicon ingot was as high as 80% and the initial carbon concentration decreased by 85%. The purification was essentially controlled by the residence time of particles in the hottest zones of the plasma jet and the partial pressure of oxygen in the processing atmosphere.

Keywords : Silicon kerf Thermal plasma Waste recovery Solar-grade silicon

Type de document :

Article dans une revue

Domaine :

Chimie / Matériaux

Sciences de l'ingénieur [physics] / Matériaux

Liste complète des métadonnées

https://hal-unilim.archives-ouvertes.fr/hal-01875458
Contributeur : Beatrice Derory <>
Soumis le : lundi 17 septembre 2018 - 14:06:26
Dernière modification le : mardi 18 septembre 2018 - 01:14:31

Use of a thermal plasma process to recycle silicon kerf loss to solar-grade silicon feedstock

Identifiants

Collections

Citation

Exporter

Métriques

34

Use of a thermal plasma process to recycle silicon kerf loss to solar-grade silicon feedstock

Identifiants

Collections

Citation

Exporter

Partager

Métriques

34