Posted on 13 Oct, 2019
1. Introduction to RFID antenna manufacturing methods
Antenna manufacturing technology is mainly coil winding method in the low frequency band. The general UHF and high frequency antenna manufacturing methods mainly include etching method, electroplating method and printing method.
1.1 etching method
First, a resist ink is printed on the metal foil-coated PET film to protect the antenna line pattern from being eroded during etching, and then baked, etched, and cleaned to obtain the antenna pattern we need. The advantages of this method are: the process is mature, the yield of antenna production is high, and the performance of the antenna is very consistent; the disadvantage is that the etching process is slow, resulting in slow antenna production; due to the use of the reduction process, Most of the copper foil is etched away, which results in a relatively high cost.
1.2 Printing method
The antenna pattern is printed on a PET substrate by a conductive silver paste, and then baked and cured to obtain an antenna manufacturing process. The advantages of this method are: fast production speed and flexible production, which can be applied to small batch production.
The disadvantages of this method are: 1 The conductivity of the conductive silver paste is far less than that of the copper foil (about 1/20 of it), the conductor loss of the antenna is relatively large, resulting in the antenna efficiency is not as good as the etching antenna; 2 conductive silver paste on the PET base The adhesion of the material is not good and it is easy to fall off, resulting in low reliability of the antenna. 3 Recently, the price of silver has risen sharply, which has led to a significant increase in the cost of conductive silver paste, which has weakened its cost advantage.
1.3 Electroplating method
First, the antenna pattern is directly printed on the PET substrate by conductive silver paste (thickness is thinner than the printing method) or other electroplated seed layer, baked and then plated thickened to obtain the finished antenna. The advantage of this method is that the production speed is fast, the antenna conductor loss is small, and the performance of the antenna is good. The downside is that the initial equipment investment is large and it is only suitable for mass production.
1.4 Vacuum coating method
First, the Masking is printed on the PET substrate to form the reverse pattern of the RFID antenna, and then the aluminum layer or the copper layer is plated by vacuum coating. Finally, the RFID antenna is formed through the De-masking process.
The advantage of this method is that the production speed is fast and the cost is relatively low; the disadvantage is that the deposited film is about 2 μm, which is far lower than the 18 μm of etching and plating. The performance of the antenna is between etching and printing. The equipment for vacuum coating is about one million US dollars, and the equipment investment is very large. Similar to electroplating, it is suitable for mass production.