A numerical investigation of dopant segregation by modified vertical gradient freezing with moderate magnetic and weak electric fields

• Published in: International journal of engineering science Vol. 43; no. 11; pp. 908 - 924
• Main Authors: Wang, X., Ma, N., Bliss, D.F., Iseler, G.W.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-07-2005; Elsevier
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); General theory; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Spray coating techniques; Crystal growth; Immersed body; Semiconductor materials; Segregation; Stirring; Doping; Electric currents; Electromagnetic stirring; Hydroelasticity; Modelling; Transport processes; Crystal growth from melts; Melts
• ISSN: 0020-7225; 1879-2197
• DOI: 10.1016/j.ijengsci.2005.03.001

The paper numerically investigates melt growth of doped gallium-antimonide (GaSb) semiconductor crystals by the vertical gradient freeze (VGF) method utilizing a submerged heater. Electromagnetic (EM) stirring can be induced in the gallium-antimonide melt just above the crystal growth interface by applying a small radial electric current in the melt together with an axial magnetic field. The transport of any dopant by the stirring can promote better compositional homogeneity. This investigation presents a numerical model for the unsteady transport of a dopant during the VGF process by submerged heater growth with a moderate axial magnetic field and a weak electric field. Numerical predictions of the dopant distributions in the crystal and in the melt at several different stages during growth are presented.