After trimming, polishing and cleaning, each wafer is finally plated with metal electrodes (full plating on the front and keyhole shaped plating on the back). After testing, it can be packaged for factory use.
However, how does such a chip work? Scientists first found some Crystalline material For example, quartz can generate current (commonly known as piezoelectricity) just like a battery after being squeezed. On the contrary, if a battery is connected to a piezoelectric crystal, the crystal will compress or expand. If the current is switched continuously and quickly, the crystal will vibrate. Recycling of crystal oscillator
Used crystal wafers can be reused in two main ways:
(1) Completely remove the film and electrode on the crystal oscillator, and re mail it back to the manufacturer to plate the electrode.
(2) Due to the fact that the gold electrode is insoluble in strong acids such as sulfuric acid, the customer handles it by himself, and removes part of the film on the crystal oscillator and reuses it. Most domestic customers dispose of the used crystal wafers themselves to save costs.
However, pay attention to the following items when using the reprocessed crystal oscillator:
(1) Silver aluminum alloy is soluble in various acids and is not suitable for reprocessing.
(2) When removing the crystal oscillator film with acid, it must have a certain impact on the substrate or appearance, and the initial frequency will also change. Put it into the crystal control
The instrument will find that the initial reading changes or the displayed life decreases, which will not affect the basic functions of the crystal plate, but the life of the crystal plate will be greatly reduced.
Cleaning formula of crystal oscillator: 20% ammonium hydrogen fluoride aqueous solution, soak for more than 6 hours, put alcohol to wipe after soaking, and then remove water.
