A method for detecting the sealing property of a quartz crystal resonator

Abstract

The application relates to a quartz crystal resonator sealing detection method, which relates to the detection of a quartz crystal oscillator. The technical scheme of the application comprises three steps of A1, A2 and A3 of conventional liquid detection, three steps of B1, B2 and B3 of reverse diffusion leak detection, and two steps of C1 and C2 of structure strength leak detection. The liquid detection, gas detection and crack detection are sequentially carried out, the requirements of conventional leak detection, reverse diffusion leak detection and structure strength leak detection can be met, and the problems of missed detection and false detection do not occur. The detection equipment has low investment and low cost. The detection time is short, and the efficiency is high.

Description

Technical Field

[0001] This invention relates to a method for detecting the sealing performance of a quartz crystal resonator, specifically for the detection of quartz crystal oscillators. Background Technology

[0002] Whether a crystal leaks after encapsulation is a crucial indicator of its reliability. Currently, the primary method for detecting leaks in quartz crystal resonators is the liquid pressurization method. This method involves placing the product in a pressurization tank, injecting alcohol or fluorinated oil, and then adding compressed air to maintain a pressure of 5 kg for 30 minutes. The product is then removed, its surface dried with a towel, and its frequency and electrical performance tested. If the seal is poor, alcohol or fluorinated oil will seep into the product through gaps, altering the measured electrical performance. Therefore, the product is considered leaky and unqualified. This testing method is commonly referred to in the industry as liquid testing.

[0003] Quartz crystal resonators are essential electronic components in most electronic devices, with a wide range of applications. Their use has become increasingly prevalent with the development of technologies such as aerospace, high-speed rail, and deep-sea exploration. As a result, the size of these products is decreasing, and the requirements for their various technical parameters are becoming increasingly stringent. Therefore, the testing methods and techniques for finished quartz crystal resonators are becoming increasingly important. Summary of the Invention

[0004] The purpose of this invention is to provide a method for testing the sealing performance of quartz crystal resonators. Qualified finished quartz crystal resonators tested using this method can be mounted on circuit boards to create electronic devices that can be used in extreme environments in fields such as aerospace and high-speed trains, meeting the requirements of these fields.

[0005] The present invention provides a method for testing the sealing performance of a quartz crystal resonator, characterized by comprising the following steps in sequence:

[0006] A1: Place the quartz crystal resonator to be tested into a sealed liquid test tank, ensuring that the quartz crystal resonator is completely submerged in the test liquid; introduce compressed air at 0.2Mpa-0.5Mpa into the liquid test tank and maintain this for 60-120 minutes;

[0007] A2: Then, remove the quartz crystal resonator from the liquid test tank and clean and dry its outer surface under normal temperature and pressure conditions;

[0008] A3: Then, put the cleaned and dried quartz crystal resonator into the testing cabinet for frequency performance testing, and sort out the liquid test qualified products and liquid test unqualified products.

[0009] B1: Place the qualified liquid sample into a sealed gas detection container and evacuate for 3-5 minutes to achieve a vacuum level of 2×10⁻⁶. -3 Then, fill the gas detection tank with 0.3 MPa to 0.5 MPa of helium and maintain the pressure for 50 to 100 minutes.

[0010] B2: After B1 is completed, release the pressure in the gas detection tank and take out the quartz crystal resonator. Let it stand at room temperature and pressure for 15-30 minutes to remove the helium gas remaining on the surface of the quartz crystal resonator.

[0011] B3: After removing the quartz crystal resonator from the gas detection canister after completing B2, place it into the leak detection cup of the helium mass spectrometer leak detector 15-75 minutes later, and perform the test according to the prescribed operating procedure, separating the helium-test qualified products from the helium-test unqualified products.

[0012] The above-mentioned method for testing the sealing performance of a quartz crystal resonator, after completing step B3, includes the following steps:

[0013] C1: Place the qualified liquid sample in a sealed high-pressure container, evacuate the vacuum, and maintain the vacuum level at 3×10⁻⁶. -5 Let it stand for more than 600 minutes;

[0014] C2: Remove the quartz crystal resonator from the high-pressure tank. Visual inspection shows that those without deformation or cracks are qualified products.

[0015] In the above-mentioned method for testing the sealing performance of a quartz crystal resonator, the testing liquid in step A1 is fluorinated oil.

[0016] The above-mentioned method for testing the sealing performance of a quartz crystal resonator includes step B1: placing the qualified liquid sample into a sealed gas testing container, evacuating for 3-5 minutes to achieve a vacuum level of 2×10⁻⁶. -3 Then, fill the gas detection tank with 0.45 MPa helium gas and maintain the pressure for 55-65 minutes.

[0017] The beneficial effects of this invention are that by performing liquid testing, gas testing, and crack testing in sequence according to this detection method, the requirements of conventional leak detection, reverse diffusion leak detection, and structural strength leak detection can be met without missed or false detections. Furthermore, the detection equipment requires minimal investment and has low cost. The testing time is short and the efficiency is high. Detailed Implementation

[0018] This invention discloses a method for testing the sealing performance of a quartz crystal resonator, comprising the following steps in sequence:

[0019] A1: Place the quartz crystal resonator to be tested into a sealed liquid testing tank, ensuring it is completely submerged in the fluorinated oil testing solution; introduce compressed air at 0.2 MPa to 0.5 MPa into the tank and maintain this pressure for 60 to 120 minutes. A2: Then, remove the quartz crystal resonator from the tank and clean and dry its outer surface under normal temperature and pressure conditions. A3: Place the cleaned and dried quartz crystal resonator into a testing cabinet for frequency performance testing, separating those that pass the liquid testing from those that fail. These steps A1, A2, and A3 are called liquid testing, also known in the industry as preliminary testing. This liquid testing is a routine test. Quartz crystal resonators that pass this routine test are suitable for general use under normal temperature and pressure conditions, conforming to national standards and can be used in general electrical appliances under normal temperature and pressure conditions.

[0020] After liquid testing is completed, B1: Place the qualified liquid-tested sample into a sealed gas testing container and evacuate for 3-5 minutes to achieve a vacuum level of 2×10⁻⁶. -3 Then, fill the gas detection canister with 0.3Mpa-0.5Mpa helium gas and maintain the pressure for 50-100 minutes; B2: After B1 is completed, release the pressure in the gas detection canister and remove the quartz crystal resonator. Let it stand at room temperature and pressure for 15-30 minutes to remove any residual helium gas from the surface of the quartz crystal resonator; B3: After B2 is completed, remove the quartz crystal resonator from the gas detection canister and place it in the leak detection cup of a helium mass spectrometer leak detector for 15-75 minutes. Then, perform the test according to the prescribed operating procedures and sort out the helium-tested products and the helium-tested products that fail the test. These steps B1, B2, and B3 are called gas detection, also known in the industry as fine detection, which belongs to reverse diffusion leak detection. Quartz crystal resonators that pass this gas detection test can meet the general use of high-end electronic products.

[0021] After completing step B3, proceed with the following steps: C1: Place the qualified liquid sample in a sealed high-pressure container, evacuate the vacuum, and maintain the vacuum level at 3×10⁻⁶. -5 C1: Let it stand for more than 600 minutes; C2: Remove the quartz crystal resonator from the high-pressure tank and visually inspect it with a magnifying glass. If the quartz crystal resonator has no deformation, cracks or other structural damage, it is a qualified product. These C1 and C2 steps are called crack inspection, which is a structural strength leak test for quartz crystal resonators. Qualified quartz crystal resonators that meet the crack inspection requirements can meet the extreme environments in fields such as aerospace and high-speed trains.

[0022] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A method for detecting the sealing performance of a quartz crystal resonator, characterized in that... The steps are included in sequence: A1: Place the quartz crystal resonator to be tested into a sealed liquid test tank, ensuring that the quartz crystal resonator is completely submerged in the test liquid; introduce compressed air at 0.2Mpa-0.5Mpa into the liquid test tank and maintain this for 60-120 minutes; A2: Then, remove the quartz crystal resonator from the liquid test tank and clean and dry its outer surface under normal temperature and pressure conditions; A3: Then, put the cleaned and dried quartz crystal resonator into the testing cabinet for frequency performance testing, and sort out the liquid test qualified products and liquid test unqualified products. B1: Place the qualified liquid sample into a sealed gas detection container and evacuate for 3-5 minutes to achieve a vacuum level of 2×10⁻⁶. -3 Then fill the gas detection tank with 0.3Mpa-0.5Mpa helium gas and maintain the pressure for 50-100 minutes. B2: After B1 is completed, release the pressure in the gas detection tank and take out the quartz crystal resonator. Let it stand at room temperature and pressure for 15-30 minutes to remove the helium gas remaining on the surface of the quartz crystal resonator. B3: After removing the quartz crystal resonator from the gas detection canister after completing B2, place it into the leak detection cup of the helium mass spectrometer leak detector 15-75 minutes later, and perform the test according to the prescribed operating procedure, separating the helium-test qualified products from the helium-test unqualified products.

2. The method for detecting the sealing performance of a quartz crystal resonator according to claim 1, characterized in that... After completing step B3, proceed with the following steps: C1: Place the qualified liquid sample in a sealed high-pressure container, evacuate the vacuum, and maintain the vacuum level at 3×10⁻⁶. -5 Pa, let stand for more than 600 minutes; C2: Remove the quartz crystal resonator from the high-pressure tank. Visual inspection shows that those without deformation or cracks are qualified products.

3. A method for detecting the sealing performance of a quartz crystal resonator according to claim 1 or 2, characterized in that... The detection solution in step A1 is fluorinated oil.

4. The method for detecting the sealing performance of a quartz crystal resonator according to claim 3, characterized in that... Step B1 is as follows: Place the liquid-tested qualified sample into a sealed gas detection container, and evacuate for 3-5 minutes to achieve a vacuum level of 2×10⁻⁶. -3 Then, fill the gas detection tank with 0.45 MPa helium gas and maintain the pressure for 55-65 minutes.