Observation of Gas Bubble Incorporation during Micropulling-Down Growth of Sapphire.

E.A. Ghezal (1) , A. Nehari (2) , K. Lebbou (1) , T. Duffar (3)

1 LPCML - Laboratoire de Physico-Chimie des Matériaux Luminescents
2 RSA RUBIS DSA
3 SIMaP - Science et Ingénierie des Matériaux et Procédés

Quite often sapphire shaped crystals contain specific defects called bubbles of average diameter higher than 100 mu m or microbubbles of diameter smaller than 10 mu m. These defects strongly affect the crystal properties. Bubbles of 100 mu m in diameter have been observed in the molten zone during micropulling-down of sapphire fibers. Before their incorporation inside the crystal, they show a periodic oscillation and consequently deform the crystallization interface. These observations are discussed with reference to the available literature.

Domaines: Matériaux

E.A. Ghezal, A. Nehari, K. Lebbou, T. Duffar. Observation of Gas Bubble Incorporation during Micropulling-Down Growth of Sapphire.. Crystal Growth & Design, 2012, 12 (11), pp.5715-5719. ⟨10.1021/cg301232r⟩. ⟨hal-00781286⟩