Pre-plating preparation and electroplating treatment of thick copper PCB：
The main purpose of thickening copper plating is to ensure that there is a thick enough copper plating layer in the hole to ensure that the resistance value is within the range of the process requirements. As a plug-in part, it is to fix the position and ensure the connection strength; as a surface-encapsulated device, some holes are only used as through holes, which play the role of conducting electricity on both sides.
1. Inspection items for thick copper PCB
（1） Mainly check the metallization quality status of the hole, and ensure that there are no extras, burrs, black holes, holes, etc. in the hole;
（2） Check whether there are dirt and other extras on the surface of the substrate;
（3） Check the number, drawing number, process file and process description of the substrate;
（4） Find out the mounting position, mounting requirements and the plating area that the plating tank can withstand;
（5） The plating area and process parameters must be clear to ensure the stability and feasibility of the plating process parameters;
（6） Cleaning and preparation of conductive parts, first energizing treatment to make the solution present in an activated state;
（7） Determine whether the composition of the bath liquid is qualified and the surface area of the electrode plate; if the spherical anode is used, the consumption must also be checked;
（8） Check the firmness of the contact parts and the range of voltage and current fluctuations.
2. Quality control of thick copper PCB
（1） Accurately calculate the plating area and refer to the influence of the actual production process on the current, correctly determine the required value of the current, grasp the current changes in the electroplating process, and ensure the stability of the electroplating process parameters;
（2） Before electroplating, first use the debugging board for trial plating, causing the bath to be in an active state;
（3）Determine the direction of the total current flow, and then determine the order of the hanging boards. In principle, it should be from far to near; to ensure the uniformity of current distribution on any surface;
（4） To ensure the uniformity of the coating in the hole and the consistency of the coating thickness, in addition to the process of stirring and filtering, impulse current is also required;
（5） Frequently monitor the current changes during the electroplating process to ensure the reliability and stability of the current value;
（6） Check whether the copper plating thickness of the hole meets the technical requirements.
