Investigation of light emitting diodes using nuclear microprobes

The quality of semiconductor p-n junctions and substrates is essential for a reliable performance of microelectronic devices. The imaging techniques o f ion beam induced charge (IBIC) and ionoluminescence (IL) are applied to i mage and analyze light emitting diodes (LEDs). The LEDs have been imaged bo th from the front (beam normal to p-n junction plane) and from the transver se direction (beam parallel to p-n junction plane). The imaging techniques provide details on the structural uniformity of the p-n junction and the :l ight emitting properties, as stimulated by proton irradiation. Following IB IC and IL analysis, PIXE and RES provide elemental distribution information on the metal layers and other components in the LEDs. The techniques which can be utilized by the nuclear microprobe potentially provide powerful too ls for the failure analysis and quality control of the fabrication of micro electronic devices. (C) 1999 Published by Elsevier Science B.V. All rights reserved.