A Nondestructive Method for Three-Dimensional Reconstruction of Lumine-scence Materials: Principles, Data Acquisition, Image Processing

摘要

In the study presented here we have tried to state-the principles and calculate and visualize models of three-dimensional (3-D)-cathodoluminescence reconstruction of luminescence structures by scanning electron microscopy (SEM). The new technique does not destroy the specimen and uses the variable energy of the electron beam to penetrate to different depths in the specimen volume. The SEM in color cathodoluminescence mode (CCL-SEM) detects integrated panchromatic CL-images for different energies of the electron beam. The use of electron scattering theory in solids and theories of cathodoluminescence and color allow the production of problem-oriented software for the routine processing of primary images. Processed images represent the CCL-SEM displays of separated layers (without CL information from other layers) up to the maximum depth penetrated by the beam. The 3-D reconstruction is carried out through algorithms developed using a personal computer, software, and a set of processed two-dimensional (2-D) images. The first experimental work was accomplished using a multilayer SiC mesastructure. The final reconstructed image of SiC material demonstrates separated epitaxial layers of different SiC polytypes and Z sections (YOZ and XOZ sections). The 3-D image represents the space distribution of CL-spectral data in color CL interpretation.