In the field of electronic materials, PET (polyethylene terephthalate) gold plating film is gradually emerging due to its unique performance combination. PET itself has good mechanical properties, heat resistance, and chemical resistance. After being coated with a layer of gold on its surface, it not only enhances the decorative effect, but also endows the material with excellent conductivity and corrosion resistance. Among them, the thickness of the gold plating layer is the key variable
PET gold-plated filmThe influence of conductivity has attracted much attention.
Basic principle: Construction of conductive pathways
Gold, as an excellent conductor, allows the outer electrons in its atomic structure to move relatively freely. In PET gold-plated film, these free electrons are the "main force" of conductivity. When the thickness of the gold plating layer is thin, the conductive path formed by the gold atoms is relatively sparse, and when electrons move in it, they encounter more obstacles, resulting in higher resistance and limited conductivity. For example, in some early studies, when the thickness of the gold plating layer is at the nanometer level, the sheet resistance of PET gold plating film can reach several hundred ohms per square (Ω/□).
As the thickness of the gold plating layer gradually increases, the number of gold atoms increases, and they are interconnected to form a more dense and continuous conductive network. This is like adding more flat and wide channels on an originally rugged and difficult road, allowing electrons to pass through more smoothly, thereby reducing resistance and improving conductivity.
Experimental data: Quantitative relationship between thickness and conductivity
Numerous experimental studies have revealed to us
PET gold-plated filmThe specific law of the variation of conductivity with the thickness of the gold plating layer. Researchers have prepared a series of PET gold plating film samples with different thicknesses of gold plating layers by precisely controlling the electroplating process. The square resistance was measured using a four probe tester, and the results showed that when the thickness of the gold plating layer increased from 5 μ m to 100 μ m, the square resistance significantly decreased from 100 Ω/□ to 25 Ω/□. This clearly indicates that as the thickness of the gold plating layer increases, the conductivity of the PET gold plating film shows a significant upward trend.
In another experiment, researchers further subdivided the thickness of the gold plating layer and studied the changes within a thinner range. When the thickness increases from 1 μ m to 5 μ m, the sheet resistance decreases from the initial value of about 500 Ω/□ to around 100 Ω/□. At this stage, although the increase in thickness is relatively small, the effect of improving conductivity is significant, fully reflecting the sensitive influence of the thickness of the gold plating layer on conductivity in the thinner thickness range.
Influence mechanism: electron scattering and interface effects
From a microscopic perspective, electron scattering phenomenon is the influencing factor
PET gold-plated filmOne of the important factors of conductivity. In thinner gold plating layers, the number of gold atoms is limited, and electrons are more likely to collide with gold atoms, grain boundaries, and possible impurities during their movement. This collision causes the direction of electron motion to change, resulting in electron scattering and increased resistance.
As the thickness of the gold plating layer increases, the crystal structure composed of gold atoms becomes more complete, the number of grain boundaries relatively decreases, the probability of electron scattering decreases, and the conductivity is improved. Meanwhile, the interface between the PET substrate and the gold plating layer also has a certain impact on the conductivity. The atomic arrangement at the interface may differ from that inside, and there may be situations such as stress and defects. When the gold plating layer is thin, the interface effect accounts for a large proportion in the entire system, causing significant interference to electronic transmission. As the thickness of the gold plating layer increases, the relative influence of interface effects weakens, and the degree of interference on conductivity decreases.
Considerations in practical applications
In practical application scenarios, such as conductive connections and electromagnetic shielding of electronic devices, the conductivity of PET gold plating film is crucial. Taking flexible circuit boards as an example, it is necessary to ensure material flexibility while also possessing good electrical conductivity. At this point, choosing the appropriate thickness of the gold plating layer is particularly crucial. If the gold plating layer is too thin to meet the low resistance requirements of the circuit, it may cause problems such as signal transmission distortion and heat generation; However, if the gold plating layer is too thick, although the conductivity is improved, it will increase the material cost and may also affect the flexibility of the PET film itself, reducing its advantages in flexible applications.
In electromagnetic shielding applications, sufficient conductivity can effectively reflect and absorb electromagnetic waves, achieving good shielding effects. This requires precise adjustment of the gold plating layer thickness of PET gold plating film based on the actual electromagnetic environment strength, shielding requirements, etc., in order to achieve the best balance between shielding performance and cost-effectiveness.
PET gold-plated filmThe conductivity is closely related to the thickness of the gold plating layer. As the thickness of the gold plating layer increases, the conductivity significantly improves, which involves various microscopic mechanisms such as electron scattering and interface effects. In practical applications, it is necessary to comprehensively consider various factors such as cost and flexibility, accurately regulate the thickness of the gold plating layer, and fully utilize the performance advantages of PET gold plating film to meet the application needs of different fields.
The above data is for reference only, and specific performance may vary due to production processes and product specifications.
