A Technique for In—Situ Detection of Growth Dislocations

Abstract

A formidable obstacle to develop the optimal conditions for growing dislocation-free crystals has been the lack of a direct technique to monitor the perfection of the solid/liquid (S/L) interface during growth.Recently we have developed a technique which detects, in-situ, the emergence of dislocation(s) at the crystallization front. This novel technique is based on the thermoelectric principles, and utilizes the dependence of the Seebeck emf generated across the S/L interface upon the interface temperature, crystal orientation, and dopant concentration.The technique was used to directly measure the S/L interface temperature during growth of Ga and In-doped Ga.For the latter, the technique also shows the breakdown (instability) of the faceted interface, which leads to the entrapment of the In-rich bands.