Miniled substrate selection: PCB vs glass substrate
Sep 08, 2021
Miniled substrate includes PCB scheme and glass scheme. Among them, PCB is a commonly used LED substrate, which has the advantages of mature technology and low cost. It is mainly promoted and used by LED industry chain manufacturers. Glass substrate is one of the key materials of LCD, which is later promoted to LED substrate by panel factory. With the deepening application of miniled, the substrate is put forward higher requirements, and the relevant industrial pattern is expected to usher in a change.
1. Cost
From the material point of view, the price of PCB substrate is several times that of glass substrate. Therefore, if large-scale production is carried out, the material cost of glass substrate is actually lower.
However, from the perspective of comprehensive cost, since the light mask needs to be opened for the routing of glass substrate, the initial investment cost is high. If the scale is not high, the average cost may exceed that of PCB substrate.
In addition, from the perspective of yield, China's current packaging plants should have more mature technology, stronger reliability and higher yield for PCB substrates, so the cost is more controllable. The yield of glass substrate is low due to the fragility of glass.
Therefore, in a comprehensive view, the current PCB substrate still has cost advantages, but in the long run, with the improvement of the scale and yield of glass substrate, the cost of glass substrate is expected to decrease significantly, even lower than that of PCB substrate.
2. Performance
The heat dissipation of PCB substrate is weaker than that of glass substrate, and due to the high heat density in chip welding, it is easy to cause the problem of warpage and deformation. Especially in large-scale applications, it is easy to produce the problem of splicing in the process of multi group backlight unit splicing.
The glass substrate has low thermal expansion rate and strong heat dissipation, so it has higher flatness and is more conducive to the welding of mini led. Therefore, the glass substrate can meet the requirements of high precision.
3. Application
PCB substrate is the choice under the current technical conditions in China. It is used by most LED products.
For higher heat dissipation requirements, higher flatness requirements or high-density assembly, glass substrate will be a better choice.
