ELECTROSTATIC DISCHARGE (ESD), FACTORY ISSUES, MEASUREMENT METHODS AND PRODUCT QUALITY
Author: Hartmut Berndt Company: B.E.STAT European ESD Competence Centre Date Published: 5/19/2011
Abstract: Particularly automated production lines have some processing steps, where electrostatic charges are increasingly generated. So far one has been focused on the human being. This is controllable. Measurements in production lines show electrostatic charges at the following processing steps: application of soldering paste (printer), assembling (automated and manual pick and place), and labeling as well as optical and electrical tests (ICT). The electronic components are always assembled directly and without any covering on the PCBs. Thus, the wire bonding process leads to a damage of the electronic components. This process step is a very critical part in the production line. The electronic devices will be directly contacted with a metal needle. All electronic components and assemblies are to be at risk of electrostatic discharges. Producers, suppliers, distributors and users have to realize the ESD control system during the whole manufacturing process, during the measurements as well as during the application. All active electronic components, beginning with simple diodes, transistors or complex inner circuits, require an extern ESD control system. In the next step, SMD resistors and condensers, and prospectively NEMS and MEMS will be included in this danger category. Tests show, that these passive components can be damaged through electrostatic discharges. The structures of electronic components become smaller. Already 5 volts of an electrostatic charge are enough to change the structures in small electronic components. The structures will achieve such small dimensions, so electrostatic charges can cause permanent damages. In the year 2024 the sizes of the electronic components will be less than 10 nm. Electrostatic charges of 0,1 nC and electrostatic fields of 10 V/cm (or 1000 V/m) will be enough then to damage ESDS permanently.