Surface-mount technology (SMT) is the leading factor driving higher circuit densities per square inch on PCBs. Directly attaching components and devices to the surface of circuit boards has enabled products to perform with much higher circuit speeds, allowed greater circuit density, and requires fewer external connections. These advances have greatly lowered costs, improved performance and product reliability. However, these benefits do not come without their challenges. Printing solder paste on diminishing pad sizes, placing smaller components, and reflowing entire assemblies with their varieties of termination finishes and materials are just a few of the technical challenges that process engineers face every day.