X-RAY DIFFRACTION INTENSITY RATIO METHOD FOR THE THICKNESS MEASUREMENT OF TERNARY, HETEROGENEOUS EPITAXIAL LAYERS ON A GaAs SUBSTRATE.

On the basis of symmetric Bragg reflection, dynamic diffraction, and kinematic absorption, equations of each layer's thickness connected with the intensity ratios of certain X-ray diffraction lines have been derived for systems with multi-epitaxial layers on GaAs sustrates. The values of the intensity ratio are measured experimentally by X-ray diffraction. Consequently, the thicknesses of various epitaxial layers can be determined. The measured results of kinematic absorption agree fairly well with those of the cleavage method. Finally, the effect of various factors on the measured results is discussed briefly.