PI Copper Plating Film: What is the thermal compatibility between PI substrate and copper plating layer?

In recent years, with the rapid development of the electronics industry, the demand for materials has also been increasing. Among them,Polyimide (PI) copper plated filmWith its unique performance combination, it has become a new favorite in fields such as microelectronic packaging and flexible circuits. However, the thermal matching problem between PI substrate and copper plating layer has always been one of the key technical challenges that restrict its widespread application. This article will explore the thermal stability performance of PI copper plated film under different treatment conditions through experimental data comparison, and analyze the thermal matching problem between PI substrate and copper plated layer.

Experimental methods

The experiment was conducted usingAdvanced Institute (Shenzhen) Technology Co., LtdProvide high-quality PI copper plated film samples. In order to investigate the thermal matching between PI substrate and copper plating layer at different temperatures, we designed a series of experiments to simulate temperature changes in actual working environments. The main testing items include:

1. Measurement of coefficient of thermal expansion (CTE): Use a thermal mechanical analyzer (TMA) to measure the CTE values of the PI substrate and copper plating layer at room temperature to 250 ° C.
2. Bonding force test: Standard tape method is used to test the bonding force between PI substrate and copper plating layer after different temperature treatments.
3. Surface morphology analysis: Using scanning electron microscopy (SEM), observe the surface morphology changes of PI copper plated film samples before and after high-temperature treatment.

Experimental Results and Discussion

The results of the thermal expansion coefficient measurement show that the CTE value of the PI substrate gradually increases within the temperature range of 25 ° C to 250 ° C, while the CTE of the copper plating layer remains at a relatively stable level. This means that as the temperature increases, thermal mismatch will inevitably occur between the PI substrate and the copper plating layer, resulting in stress at the interface.

To further verify the above conclusion, we conducted a binding force test. The experiment found that the bonding strength of the sample meets industrial standards without undergoing high-temperature treatment; But when the samples were subjected to continuous high temperatures above 200 ° C, some samples showed a significant decrease in binding strength. This is consistent with the CTE measurement results, indicating that high temperatures exacerbate the degree of thermal mismatch between the PI substrate and the copper plating layer.

In addition, SEM observations showed varying degrees of cracks and blistering on the surface of the sample after high-temperature treatment, especially at the interface between the PI substrate and the copper plating layer. This further confirms the negative impact of thermal mismatch.

conclusion

In summary, althoughPI copper plated filmIt has shown great potential in fields such as microelectronic packaging, but the thermal matching between its PI substrate and copper plating layer is still an urgent problem to be solved. Experimental data shows that as the temperature increases, the thermal mismatch between the two becomes more significant, leading to a decrease in bonding strength and an increase in interface defects. Therefore, in future product design and production process optimization, it is necessary to consider introducing new materials or improving existing preparation technologies to enhance the overall thermal stability of PI copper plated films.

The above data is for reference only, and specific performance may vary due to production processes and product specifications.