Issue link: https://iconnect007.uberflip.com/i/871322
September 2017 • The PCB Magazine 39 generally on copper-clad substrates. Plating acceptability is judged by plating thickness, adhesion, ductility and uniformity (the pres- ence of inclusions, nodules, voids or cracks). Factors that affect these criteria are board s ur- face preparation, board racking and handling, control of chemical parameters, and physical parameters of the plating operation (solution filtration, distribution, anode/cathode place- ment and geometry, etc.). Some of these variables are capable of "im- mediate" control by the operator (adjustment PROCESS ENGINEERING & DEFECT PREVENTION Figure 2: Nearly etched-out circuit trace. (Source: RBP Chemical Technology) Figure 3: Electroplated copper cracks after thermal excursion. (Source: RBP Chemical Technology) Table 3: Possible causes and solutions for copper cracking in barrel of hole. (Excerpted from IPC-9121 Section 7.4 Hole Preparation and Protection) Table 2: Possible causes and solutions for over-etched/ missing copper. (Excerpted from IPC-9121 "Trouble Shooting for Board Fabrication Processes," Section 10.2 Etching) s