Main problems that need to be solved in the production of HDI PCB circuit boards

Main problems that need to be solved in the production of HDI PCB circuit boards

The production of HDI (high-density interconnect) circuit boards is a complex and technology-intensive process involving challenges that need to be overcome in multiple links. The following are some of the main problems that need to be solved in the production of HDI circuit boards:

1. Stress problems caused by differences in the thermal expansion coefficients of materials

Problem description: HDI circuit boards are composed of multiple layers of materials, which may have different thermal expansion coefficients. When the temperature changes, different materials shrink and expand to different degrees, which may cause stress inside the circuit board, which in turn causes interlayer separation, cracking or deformation.

Solution: Choose a suitable combination of materials and control the thickness and size of the circuit board. In addition, the use of appropriate temperature cycles and aging tests are also important mitigation measures.

2. Stability of pins

Problem description: The pins on HDI circuit boards are small in size and are easily affected by mechanical shock or vibration, causing the pins to break or fall off.

Solution: Improve the strength and stability of the pins, use high-quality solder and welding processes, and strengthen the fixation and protection of the pins.

3. Circuit blocking

Problem description: The circuits on HDI circuit boards are connected by fine wires or holes. These structures are easily affected by pollution, oxidation or damage, resulting in circuit blockage or short circuit.

Solution: Improve the cleanliness and flatness of the wires or holes, use high-quality copper cladding and gold plating processes, and adopt effective detection and repair methods.

4. Production difficulty and precision problems

Problem description: The difficulty of making HDI boards is mainly reflected in the following aspects:

Interlayer connection difficulty: There are many layers of circuits and concentrated connection points. If all connections are perforated, the perforation frequency will inevitably be too high, affecting the stability of the circuit and the performance of the board.

Blind hole production difficulty: The production technology requirements for blind holes are higher, because they cannot be repaired after perforation. Once the quality is unqualified, a new board needs to be made.

Line precision: The line width and line spacing of HDI board circuits are also difficult to make. HDI boards have many layers, and the lines are getting thinner and thinner. There are also strict requirements for the position, thickness, bending angle, etc. of the lines.

Solution: Select high-performance materials, optimize process flow, adopt advanced production equipment and technology to ensure the accuracy and reliability of each step.

5. Efficiency and cost issues of production lines

Problem description: Under the condition that the cost of customized HDI circuit board production lines continues to rise, how to improve the current production line yield and material prices, especially under the condition of high copper prices, how to balance product stability, product quality and economic benefits is also worth considering.

Solution: Optimizing equipment and current density can increase output, no serious contamination of copper surface layer, low plating finish, and low serious contamination of plating solution. The optimized plating solution can control the base copper within the range of 1 to 5μM.

6. Innovation and competitiveness issues

Problem description: HDI circuit board factories must continuously carry out technological innovation and management innovation in order to surpass competitors and seize market opportunities.

Solution: The production of HDI circuit boards is a multi-step process involving material selection, manufacturing process control, precise operation of equipment and other aspects. Solving these problems requires not only advanced technology and equipment, but also strict quality management processes and perfect innovation mechanisms.

7. Lamination problem

Problem description: Lamination of HDI boards is an important process in the production process, and the production process of lamination directly affects the reliability of HDI board products. Problems such as interlayer offset and warping may occur during lamination.

Solution: Use advanced lamination technology and equipment, such as rivet positioning and solder joint positioning, to ensure that the holes and lines of different layers have a good alignment relationship; pre-compensate before lamination to reduce the deviation after lamination.

8. Pollution problem

Problem description: The pollutants on the PCB circuit board directly affect its appearance and performance. Under high temperature and humid conditions, the residue may absorb moisture and turn white, causing corrosion, short circuit and other faults.

Solution: Strictly control the cleanliness of the production environment and use efficient cleaning processes to ensure that the surface of the circuit board is clean and pollution-free.

9. Difficulty in manufacturing multi-level HDI boards

Problem description: The manufacturing process of multi-level HDI boards is more complicated and requires multiple laminations and laser drilling. This not only increases the complexity of the process, but also increases the difficulty in alignment, drilling and copper plating.

Solution: Select high-performance materials, optimize the process flow, and adopt advanced production equipment and technology to ensure the accuracy and reliability of each step.

By solving the above problems, the production quality and reliability of HDI circuit boards can be improved to meet the needs of various high-end applications.