Quartz crystal resonator/oscillator and design method thereof

Abstract

The invention discloses a quartz crystal resonator / oscillator and a design method thereof, and belongs to the technical field of components. According to the technical key points, the resonator / oscillator comprises a base material and a three-layer coating structure, the base material is a quartz crystal, and the three layer coating structure is symmetrically arranged on the two sides of the base material; the three-layer coating structure sequentially comprises an expansion inhibition material layer, a high-heat expansion coefficient material layer and an adhesion bonding material layer in the direction pointing to the quartz crystal; the frequency tested before reflow soldering is recorded as f, the frequency measured 0.5 hour after three times of reflow soldering is recorded as f1, and |f1-f| / f is smaller than 2 ppm; and the temperature of a reflow soldering area of each reflow soldering of the three times of reflow soldering is 217 DEG C, the time is kept for 60-150 seconds, the peak temperature is 260 + / -5 DEG C, and the time is kept for 20-40 seconds. By adopting the quartz crystal resonator / oscillator and the design method thereof, the technical requirements of the high-performance quartz crystal resonator / oscillator for communication can be effectively met.

Description

technical field [0001] The present invention relates to the technical field of components, and more specifically relates to a quartz crystal resonator / oscillator and a design method thereof. Background technique [0002] Quartz oscillators are usually called quartz crystal resonators / oscillators. The basic principle is to form conductive electrodes made of silver on both sides of the quartz oscillator. When a voltage is applied to the electrodes, due to the electrostrictive effect Deformation force, and the vibration is generated by the deformation force, and the vibration frequency is determined according to the dynamic characteristics of the quartz vibrator. [0003] The basic characteristic of a quartz crystal is that it has two resonant frequencies: fs, fp: [0004] 1) When f<fs, the quartz crystal is capacitive, which is equivalent to capacitance. [0005] 2) When f=fs, the quartz crystal is resistive, which is equivalent to a resistor with a small resistance. [...

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Problems solved by technology

[0018] The first problem: adopting CN102739186B or the technical scheme, placed under the current requirements (double or three reflow soldering), in fact it cannot meet the requirements (reflow soldering test: 72 hours)

[0019] The second question: In addition, more importantly, due to the production efficiency requirements of downstream enterprises: after the quartz crystal resonator / oscillator has undergone double or three reflow soldering, after the shortest possible time, The next step can be carried out on the quartz crystal resonator / oscillator, thereby saving a lot of time requirements; the corresponding test conditions are: after three reflow soldering tests, △f / f is less than 2×10 -6 The smaller the time, the better

In fact, it is not acceptable to do so, and it will lead to a large number of non-quality products

[0021] The third question: The current reflow soldering test conditions are: peak temperature 260°C (essentially: 260°C ± 5°C), peak temperature time is about 10s (see literature: Yang Yang, Cai Liangxu, Lu Haotian, etc. Crystal Oscillator Frequency drift failure analysis of resonators[J].Electronic Product Reliability and Environmental Test,2014,32(003):34-37.); It does not match the reflow soldering time of high-performance communication quartz crystal resonators / oscillators (mainly is that the duration of the peak temperature is too short), it will also cause: the products produced by applying the scheme of CN102739186B or the products developed under the existing test conditions cannot meet the requirements of new high-performance communication quartz crystal resonators / oscillators

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