An apparatus for performing non-contact material characterization includes a wafer carrier adapted to hold a plurality of substrates and a material characterization device, such as a device for performing photoluminescence spectroscopy. The apparatus comprises plates which initially have a width smaller than the diameter of the well bore to be sealed or plugged. The network management module provides at least one tunnel to accommodate the multiple virtual access points. Each of the electrodes includes a tapered portion having a width which reduces as progressing toward a corresponding one of the heating portions 2. Longitudinal score lines divide the cover cap into a plurality of first sections and a single second section.