HIGH-RESOLUTION QUANTITATIVE CATHODOLUMINESCENCE (CL) FOR DEFECT METROLOGY IN SEMICONDUCTORS

摘要

High spatial resolution spectroscopic information may be acquired by using an electron beam in a modern scanning electron microscope (SEM), exploiting a phenomenon called cathodoluminescence (CL). CL refers to the light that is emitted by any material under electron beam irradiation. In a semiconducting material, electrons are promoted from the conduction band to the valence band upon impingement of the primary high energy electrons. The emitted CL results from recombination of these excited electrons, and therefore provides an information on local bandgap variations that may originate from strain, alloy fluctuations, defects, impurities, etc. [1-9, 16]. This makes CL a very powerful, non-destructive, high resolution spectroscopy method.