In-depth analysis of multi-layer PCB board production process and precautions for you
Multi-layer PCB boards are laminated by internal and external multi-layer circuits. In production, they are different from single- and double-sided circuit boards. The first step in the production process of multi-layer PCB boards is the inner circuit. Then its process has What are the steps? Next, the editor of Changdongxin Circuit Board Factory will take you to learn more about the inner circuit process.
1. Cutting
1. Cutting material: Cut a large sheet of material into the required production size according to the size requirements.
2. Baking: In order to eliminate the internal stress generated during the production of the sheet and strengthen the dimensional stability of the sheet. Remove the moisture absorbed by the sheet during storage and enhance the reliability of the material.
3. Round corners of gongs: To standardize the operation, round the corners of the gongs.
2. Pre-process processing
1. Degreasing: Remove the oily substance oxide film on the copper surface by acidic chemicals.
2. Micro-etching: The principle is that an oxidation-reduction reaction occurs on the copper surface to roughen the copper surface.
3. Pickling: to remove copper ions and reduce the oxidation of the copper surface
4. Hot air drying: Dry the board surface.
Three, line etching
1. Development: Under the action of the syrup sodium carbonate, the unexposed part of the ink is dissolved and washed, and then the photosensitive part is discarded.
2. Etching: Etch off the copper surface of the unexposed copper exposed part.
3. Removal: The ink on the copper surface of the protection circuit is removed by a higher concentration of sodium hydroxide.
4. Punching: Through the set target, punch out the pipe position holes in the uniform position of each layer, and use the layout of the next process for positioning.
Four, optical inspection
1. Optical inspection: It is an equipment that detects common defects encountered in welding production based on optical principles. AOI is a new type of test technology that is emerging, but it is developing rapidly, and many manufacturers have introduced AOI test equipment. During automatic inspection, the machine automatically scans the PCB through the camera, collects images, compares the tested solder joints with the qualified parameters in the database, after image processing, checks out the defects on the PCB, and displays/marks the defects through the display or automatic signs Come out and be repaired by maintenance personnel.
2. Target inspection confirmation: visual inspection confirmation, confirm or eliminate some true and false defects.
3. Visual inspection: repair or scrap the confirmed defects, and classify different levels.
The above is the production process of the inner layer of multi-layer PCB. We have more than ten years of experience in PCB production and processing. We are committed to the production and processing of multi-layer boards, with quality assurance, a wide range of production varieties, and a wide range of coverage. Welcome to inquire.