The manufacture of reed pipes, high standards of clean environment and high precision are essential. Therefore, all processes are performed in a clean room environment. At the same time, it is necessary to ensure that no contaminants enter the glass tube during the sealing process. The reed must be annealed. The annealing process can remove the hysteresis on the metal and stabilize the reed's magnetic susceptibility to avoid the occurrence of defective products. Then, the reeds are thoroughly cleaned by carbon dioxide cleaning, and the tiny carbon dioxide crystals are strongly blown to the reed metal to remove the foreign particles adhering to the reeds. Afterwards, a 1 micron thick layer of tantalum or niobium is precisely plated by sputtering. The bottom layer is tungsten with a thickness of about 0.2 micron.
After that, the glass tube was assembled with the ferro-alloy reeds. Before sealing the glass tube, the air in the tube is completely discharged and filled with an inert gas mixture mainly composed of helium. This process can greatly increase the insulation and pressure resistance of reed tubes. After the glass tube is sealed, annealing is performed to eliminate the residual stress in the glass structure. The leads on the outside of the Reed bulb are all tin-plated leads to ensure a good soldering effect. The Sn layer is approximately 8 to 12 microns thick.
In the manufacturing process of the reed switch, the metal reed is embedded in the end of the glass tube. Using the principle of the glass tube to absorb infrared rays, the end of the glass tube is heated using an infrared heating setting so that the end of the glass tube is fused and sealed with the reed. The coefficient of thermal expansion of the glass tube and the metal reed must be close enough to prevent the glass tube and the metal from being easily broken when sealed. At the same time, the glass tube must have a high reactance value and must not contain volatile substances such as lead oxide and fluoride. The reed switch pins must be carefully handled to prevent breakage of the glass tube.