1. The most important thing in the quartz crystal oscillator is the quartz wafer. In the manufacturing process of the quartz wafer, the raw material of the quartz crystal must be cut and polished. One of the most important steps is the fixed angle. Due to the different orientations of the quartz wafer, its piezoelectric The characteristics, strength characteristics, and elastic characteristics are different, so the performance of the quartz crystal made with it is also different. First, we need to polish and cut the quartz crystal rod. Cut out the quartz wafer corresponding to the frequency point. (It should be noted that there is a one-to-one correspondence between the quartz wafer and the frequency point.) The cutting angle at this time determines the basic frequency deviation of the quartz crystal oscillator.

2. Silver plating: In order to improve working accuracy, a layer of pure silver should be plated on the cut quartz wafer.

3. Dispensing: Silver glue (conductive glue) should be used to fix the base. The fixed angle at this time again determines the basic frequency deviation of the quartz crystal.

4. Test: At this time, with the test equipment, the output frequency of the quartz crystal can be measured. During the test, the silver can be added again for fine-tuning to improve the working accuracy.

5. Sealing and welding: If it is a passive crystal, it can be filled with nitrogen and sealed. For active crystal oscillators, the oscillator chip needs to be added and then sealed with nitrogen.

6. Leakage inspection: check whether the sealed product has air leakage. Divided into coarse leak detection and fine leak detection

7. Rough leak detection: check for larger leaks (differential pressure method)

Fine leak detection: check for minor air leaks (pressure He method)

8. Aging and simulated reflow soldering: The product is subjected to high temperature and long-term aging to release stress and simulate the customer trial environment to expose manufacturing defects to improve the reliability of the shipped products.

9. Marking: Use Laser to mark the crystal on the crystal shell, such as model, rated frequency, etc., to distinguish different products.

10. Test packaging: test the electrical performance index of the finished product, remove defective products, and ensure product quality