Author Type

Graduate Student

Date of Award

1993

Document Type

Thesis

Publication Status

Version of Record

Submission Date

October 2026

Thesis/Dissertation Advisor [Chair]

Tsai, Chi-Tay

Abstract

The dislocation density in the Gallium Arsenide (GaAs) crystal is generated by the excessive thermal stresses during Czochralski (CZ) growth process. A constitutive equation which couples the dislocation density with the plastic deformation is employed to simulate the dislocation density in the crystal. The temperature distribution in the crystal during growth process is obtained by solving the quasi-steady-state (QSS) heat transfer equation. The thermal stresses induced by the temperature distribution are calculated by finite element method. The resolved shear stress (RSS) in each slip system is obtained by stress transformation. The dislocation motion and multiplication in each slip system are simulated using the constitutive equation and the total dislocation density in the crystal is obtained. The dislocation density is also found to be affected by the growth orientation, growth speed, ambient temperature and the radius of the crystal. The dislocation density in GaAs crystals grown from different growth orientation and crystal radius at various ambient temperatures will be calculated so that the influence of these growth parameters on the dislocation density can be understood. Consequently, one can control the growth parameters to reduce the dislocation density generated in the crystal during the CZ growth process.

Extent

88 p.

Comments

College of Engineering and Computer Science|FAU Electronic Theses and Dissertations Collection|Thesis (M.S.)--Florida Atlantic University, 1993.|College of Engineering and Computer Science

Identifier

FADT14982

Format

pdf

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