title: In Depth Analyses of LEDs by a Combination of X-ray Computed Tomography (CT) and Light Microscopy (LM) Correlated with Scanning Electron Microscopy (SEM).
abstract: In failure analysis, device characterization and reverse engineering of light emitting diodes (LEDs), and similar electronic components of micro-characterization, plays an important role. Commonly, different techniques like X-ray computed tomography (CT), light microscopy (LM) and scanning electron microscopy (SEM) are used separately. Similarly, the results have to be treated for each technique independently. Here a comprehensive study is shown which demonstrates the potentials leveraged by linking CT, LM and SEM. In depth characterization is performed on a white emitting LED, which can be operated throughout all characterization steps. Major advantages are: planned preparation of defined cross sections, correlation of optical properties to structural and compositional information, as well as reliable identification of different functional regions. This results from the breadth of information available from identical regions of interest (ROIs): polarization contrast, bright and dark-field LM images, as well as optical images of the LED cross section in operation. This is supplemented by SEM imaging techniques and micro-analysis using energy dispersive X-ray spectroscopy.
authors.affiliation: Department Lippstadt, Hamm-Lippstadt University of Applied Sciences; Joerg.Meyer@hshl.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Meyer
authors.affiliation: Department Lippstadt, Hamm-Lippstadt University of Applied Sciences.
authors.forename: Christian
authors.initials: C
authors.lastname: Thomas
authors.affiliation: Department Lippstadt, Hamm-Lippstadt University of Applied Sciences.
authors.forename: Frank
authors.initials: F
authors.lastname: Tappe
authors.affiliation: Department Lippstadt, Hamm-Lippstadt University of Applied Sciences.
authors.forename: Tekie
authors.initials: T
authors.lastname: Ogbazghi
mesh_terms: D008855:Microscopy, Electron, Scanning; D014057:Tomography, X-Ray Computed