A method for manufacturing a high-temperature-resistant high-precision quartz crystal oscillator

Abstract

The application relates to the field of electronic components, and discloses a manufacturing method of a high-temperature-resistant high-precision quartz crystal oscillator. The manufacturing method of the high-temperature-resistant high-precision quartz crystal oscillator comprises the following stages: manufacturing of a high-temperature-resistant quartz wafer; manufacturing of a high-temperature-resistant quartz crystal oscillator; manufacturing of a high-temperature-resistant oscillation circuit; electrical installation of an open oscillator; frequency modulation and baking of the open oscillator; and packaging and passivation of the high-temperature-resistant high-precision quartz crystal oscillator. At present, there is no process method that can be directly used for the processing and manufacturing of the high-temperature-resistant high-precision quartz crystal oscillator, and the research is still blank. The application solves the problem of the process manufacturing method blank of the high-temperature-resistant high-precision quartz crystal oscillator product, can realize batch production, and the products manufactured at the same time can meet the requirements of a wide temperature and high-temperature use environment of-65 DEG C to +200 DEG C, realize a wide temperature working range, and have the functions of high-temperature resistance and high-precision frequency output.

Description

Technical Field

[0001] This invention relates to the field of electronic components, specifically to a method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator. Background Technology

[0002] A quartz crystal oscillator is an electronic component that uses the piezoelectric effect of quartz crystals to generate frequency signals. It features high precision, high stability, small size, and light weight. It can generate oscillation signals with precise frequencies in circuits and is an indispensable component in various electronic devices. It is widely used in many fields such as communication networks, industrial control, automotive electronics, instrumentation, and military equipment.

[0003] Currently, the manufacturing methods for quartz crystal oscillators can mass-produce quartz crystal oscillators with an operating temperature range of -55℃ to +125℃, meeting the requirements of most fields. However, in special fields such as lunar surface exploration and deep Earth exploration, high-temperature resistant and high-precision quartz crystal oscillators with an operating temperature range of -65℃ to +200℃ are required. However, there is currently no directly applicable process for the processing and manufacturing of high-temperature resistant and high-precision quartz crystal oscillators, which is still a research gap. Therefore, a manufacturing method for high-temperature resistant and high-precision quartz crystal oscillators is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a method for manufacturing a high-temperature resistant and high-precision quartz crystal oscillator, thereby addressing the lack of manufacturing processes for high-temperature resistant and high-precision quartz crystal oscillators and enabling mass production.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator includes the following stages:

[0007] Phase 1: Fabrication of 200℃ Ultra-High Temperature Quartz Wafers

[0008] First, the quartz crystal block is ground and cut into long strip quartz crystal rods. Then, the rods are beveled and cut into long strip quartz wafers according to the AT cut type of 36°±20′. Then, they are ground and cut into quartz wafer blanks. Through grinding, high temperature washing, and etching, quartz wafers resistant to 200℃ ultra-high temperature are obtained for later use.

[0009] Phase Two: Fabrication of a 200℃ Ultra-High Temperature Quartz Crystal Oscillator

[0010] The 200℃ ultra-high temperature quartz wafers are cleaned, arranged, cleaned a second time, and coated to obtain 200℃ ultra-high temperature quartz crystal oscillators for later use.

[0011] Phase 3: Fabrication of a 200℃ Ultra-High Temperature Oscillating Circuit

[0012] First, the chip and the base are fixed together with die bond adhesive. After curing, the pins of the chip are soldered to the conductive path of the base with gold wire to obtain a 200°C ultra-high temperature oscillation circuit containing the chip and the base, for later use.

[0013] Phase Four: Electrical Installation of Open Oscillators

[0014] First, the 200℃ ultra-high temperature quartz crystal oscillator and the 200℃ ultra-high temperature oscillation circuit are bonded together with the 200℃ ultra-high temperature conductive adhesive, and then cured to obtain an open oscillator for later use.

[0015] Phase 5: Frequency tuning and baking of the open oscillator

[0016] First, fine-tune the open oscillator to obtain the required frequency, then bake it at high temperature and remove it for later use;

[0017] Phase Six: Packaging and Passivation of High-Temperature, High-Precision Quartz Crystal Oscillators

[0018] First, the open oscillator is sealed together with a sealing cover and printed with markings to obtain a high-temperature resistant, high-precision quartz crystal oscillator. Then, the high-temperature resistant, high-precision quartz crystal oscillator is passivated and re-passivated, including tests such as rough leak detection, reflow soldering, accelerated aging, helium leak detection, temperature shock, secondary reflow soldering, secondary accelerated aging, room temperature testing, and high and low temperature testing, to obtain a qualified high-temperature resistant, high-precision quartz crystal oscillator.

[0019] More specifically, the fabrication of a 200°C ultra-high temperature quartz wafer includes the following steps:

[0020] Step 1: Take quartz crystal block raw material, grind the X and Z surfaces of the quartz crystal block and cut it into strips using a multi-wire cutting machine to form quartz crystal rods for later use;

[0021] Step 2: Chamfer the four sides of the cut quartz crystal rod, check the X and Z face angles and chamfer dimensions of the quartz crystal rod, and set aside for later use;

[0022] Step 3: Place the quartz crystal rod into a multi-wire dicing machine, select the AT cutting angle, and slice the crystal at 36°±20′ to form long strip quartz wafers. Detect the angle of the long strip quartz wafers and set them aside.

[0023] Step 4: Grind the long quartz wafers through multiple passes with different grits to achieve the desired thickness, grit, and X-side dimensions. Then, cut the wafers into slices using a multi-wire cutter. Finally, grind the Z-side of the original quartz wafers to achieve the desired dimensions. Set aside for later use.

[0024] Step 5: The original quartz wafer is chemically cleaned at high temperature, and then frequency etched using a chemical agent (saturated ammonium bifluoride solution). Finally, it is sorted by frequency to obtain quartz wafers resistant to 200℃ ultra-high temperature. The obtained quartz wafers are rectangular with a length-to-width-to-thickness ratio greater than 10. They have parallel upper and lower surfaces and are equipped with a fault-proof structure, with the length direction of the wafer as the first direction.

[0025] More detailed steps are involved in the fabrication of a quartz crystal oscillator that can withstand ultra-high temperatures of 200℃, as follows:

[0026] Step 1: Place the 200℃ ultra-high temperature quartz wafer in a cleaning basket, clean it through six processes using an ultrasonic cleaner and a special cleaning solution, and then dry it in an oven at 150℃±10℃ for 30 to 60 minutes. After drying, set it aside for later use.

[0027] Step 2: Place the cleaned 200℃ ultra-high temperature quartz wafers flat on the tray of the automatic wafer sorting machine. The automatic wafer sorting machine selects undamaged 200℃ ultra-high temperature quartz wafers and transfers them to the coating fixture. After the coating fixture is full, remove it and install the cover plate for later use.

[0028] Step 3: Place the fixture containing the 200℃ ultra-high temperature quartz wafer coating in the cleaning basket, and perform a second cleaning with a special cleaning solution for the ultrasonic cleaner. Then, put it in an oven at 150℃±10℃ for 30 to 60 minutes to dry. After drying, it is ready for use.

[0029] Step 4: Place the fixture containing the 200℃ ultra-high temperature quartz wafer coating into the coating machine. Plate a chromium layer and a silver electrode layer on the upper and lower surfaces of the 200℃ ultra-high temperature quartz wafer to form electrodes and obtain a 200℃ ultra-high temperature quartz crystal oscillator for later use. The electrode size for coating is manufactured according to the design requirements. An upper surface coating electrode and a secondary electrode are formed on the upper surface of the 200℃ ultra-high temperature quartz wafer, and a lower surface coating electrode and a secondary electrode are formed on the lower surface. The upper surface coating electrode and the lower surface coating electrode are symmetrically distributed with respect to the midpoint on the upper and lower surfaces, respectively, and are all rectangular in shape.

[0030] More detailed steps are involved in fabricating a 200℃ ultra-high temperature oscillation circuit, specifically:

[0031] Step 1: Place the chip and the substrate into the automatic dispensing machine, and use die bonder to attach the bottom of the chip to the groove of the substrate. Remove and set aside.

[0032] Step 2: Place the base with the chip attached into the oven, set to 150℃±10℃, bake for 50min±10min to solidify the chip onto the base, then remove and set aside.

[0033] Step 3: Place the substrate with the chip bonded to it into the bonding machine, set the preheating temperature of the bonding machine to 160℃±10℃, and weld the chip pins to the conductive path of the substrate using gold wire to obtain a 200℃ ultra-high temperature oscillation circuit containing the chip and the substrate, for later use.

[0034] More specifically, the electrical assembly of an open oscillator includes the following steps:

[0035] Step 1: Place the 200℃ ultra-high temperature quartz crystal oscillator and the 200℃ ultra-high temperature oscillation circuit into the automatic film loading and dispensing machine, and use 200℃ ultra-high temperature conductive adhesive to bond the 200℃ ultra-high temperature quartz crystal oscillator to the 200℃ ultra-high temperature oscillation circuit. Remove and set aside.

[0036] Step 2: Place the 200℃ ultra-high temperature oscillating circuit with the 200℃ ultra-high temperature quartz crystal oscillator bonded to it onto the conveyor belt of the curing mesh belt oven. Set the first half to bake at 185℃±10℃ for more than 30 minutes and the second half to bake at 270±10℃ for more than 30 minutes. Fix the 200℃ ultra-high temperature quartz crystal oscillator onto the 200℃ ultra-high temperature oscillating circuit to obtain an open oscillator, and take it out for use.

[0037] More specifically, the tuning and baking of an open oscillator includes the following steps:

[0038] Step 1: Place the open oscillator into the fine-tuning machine and use the ion etching frequency tuning method to fine-tune the frequency of the 200℃ ultra-high temperature quartz crystal oscillator. After fine-tuning, test it according to the design parameters and set it aside for later use.

[0039] Step 2: Place the finely adjusted open oscillator into a vacuum oven, set it to 150℃±3℃, and vacuum bake for at least 24 hours. Remove and set aside.

[0040] More specifically, the packaging and passivation of high-temperature resistant, high-precision quartz crystal oscillators includes the following steps:

[0041] Step 1: Place the baked open oscillator and sealing cover into the sealing and welding machine. First, vacuum bake the open oscillator at 150℃±10℃ for 50 to 90 minutes. Then, seal the sealing cover and open oscillator in a vacuum or nitrogen-filled environment using high-frequency current parallel welding. After removing them, print the markings to obtain a high-temperature resistant, high-precision quartz crystal oscillator for later use.

[0042] Step 2: Rough leak test. Using a pressurized airtightness test fluid, the high-temperature resistant and high-precision quartz crystal oscillator is subjected to a rough leak test. No obvious air bubbles are required. Then it is taken out for use.

[0043] Step 3: Reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use.

[0044] Step 4: Accelerate aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period ahead of time. Then, test it according to the design parameters and set it aside for later use.

[0045] Step 5: Helium leak detection. Place the high-temperature resistant, high-precision quartz crystal oscillator in an anti-static mesh, put it in a pressurized container, and pressurize it with 99.99% high-purity helium gas for at least 2 hours at a pressure of 0.4–0.6 MPa. Then, place it in a helium mass spectrometer leak detector for helium leak detection. The leak rate must not exceed 5 × 10⁻⁶. -3 Pa.cm 3 The standard is / s, then retrieve it for later use;

[0046] Step Six: Temperature Shock. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into a temperature shock chamber. Set the temperature to low -65℃±3℃ and high +200℃±3℃, and perform 10 cycles of shock to test the reliability, stability, and durability of the product under different temperatures. Then, conduct tests according to the design parameters and set it aside for later use.

[0047] Step 7: Secondary reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use.

[0048] Step 8: Secondary accelerated aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period in advance. Then, test it according to the design parameters and set it aside for later use.

[0049] Step 9: Room temperature test. Under normal temperature conditions of 25℃±3℃, conduct the test according to the design parameters and set aside for later use.

[0050] Step 10: High and low temperature test. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray, put it into a temperature measuring machine, set the operating temperature range to -65℃ to +200℃, test the electrical performance parameters of the product, and then remove it for later use. Attached Figure Description

[0051] Figure 1 The flowchart is of the manufacturing method of the present invention.

[0052] Figure 2 This is a schematic diagram of the 200℃ ultra-high temperature quartz crystal oscillator structure of the present invention.

[0053] Figure 3 This is a schematic diagram of the 200℃ ultra-high temperature oscillation circuit of the present invention.

[0054] Figure 4 Top view of the open oscillator of the present invention

[0055] Figure 5 This is a schematic diagram of the product structure of the present invention.

[0056] In the figure: 1. Quartz crystal wafer resistant to 200℃ ultra-high temperature, 2. Upper surface plated electrode, 3. Lower surface plated electrode, 4. Secondary electrode, 5. Conductive path, 6. 200℃ ultra-high temperature oscillation circuit, 7. Open oscillator, 8. Base, 9. Chip, 10. 200℃ ultra-high temperature quartz crystal oscillator, 11. Sealing cover, 12. 200℃ ultra-high temperature conductive adhesive. Detailed Implementation

[0057] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0058] Example

[0059] like Figure 1 As shown, a method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator includes the following steps:

[0060] Phase 1: Fabrication of 200℃ Ultra-High Temperature Quartz Wafer 1

[0061] Step 1: Take quartz crystal block raw material, grind the X and Z surfaces of the quartz crystal block and cut it into strips using a multi-wire cutting machine to form quartz crystal rods for later use;

[0062] Step 2: Chamfer the four sides of the cut quartz crystal rod, check the X and Z face angles and chamfer dimensions of the quartz crystal rod, and set aside for later use;

[0063] Step 3: Place the quartz crystal rod into a multi-wire dicing machine, select the AT cutting angle, and slice the crystal at 36°±20′ to form long strip quartz wafers. Detect the angle of the long strip quartz wafers and set them aside.

[0064] Step 4: Grind the long quartz wafers through multiple passes with different grits to achieve the desired thickness, grit, and X-side dimensions. Then, cut the wafers into slices using a multi-wire cutter. Finally, grind the Z-side of the original quartz wafers to achieve the desired dimensions. Set aside for later use.

[0065] Step 5: The original quartz wafer is chemically cleaned at high temperature, and then frequency etched using a chemical agent (saturated ammonium bifluoride solution). Finally, frequency sorting is performed to obtain quartz wafer 1 resistant to 200℃ ultra-high temperature, which is set aside. The obtained quartz wafer 1 resistant to 200℃ ultra-high temperature is rectangular, with a length-to-width-to-thickness ratio greater than 10. It has parallel upper and lower surfaces. The quartz wafer 1 resistant to 200℃ ultra-high temperature is equipped with a fault-proof structure, with the length direction of the wafer as the first direction.

[0066] Phase Two: Fabrication of the 200℃ Ultra-High Temperature Quartz Crystal Oscillator 10

[0067] Step 1: Place the 200℃ ultra-high temperature quartz wafer 1 in a cleaning basket, clean it through six processes using an ultrasonic cleaner and a special cleaning solution, and then put it in an oven at 150℃±10℃ for 30 to 60 minutes to dry it. After drying, it is ready for use.

[0068] Step 2: Place the cleaned 200℃ ultra-high temperature quartz wafer 1 flat in the tray of the automatic wafer sorting machine. The automatic wafer sorting machine selects undamaged 200℃ ultra-high temperature quartz wafer 1 and transfers them to the coating fixture. After the coating fixture is full, remove it and install the cover plate for later use.

[0069] Step 3: Place the coating fixture containing the 200℃ ultra-high temperature quartz wafer 1 in the cleaning basket, and perform a second cleaning process of six steps using a special cleaning solution from an ultrasonic cleaner. Then, place it in an oven at 150℃±10℃ for 30 to 60 minutes to dry. After drying, it is ready for use.

[0070] Step 4: Place the coating fixture containing the 200℃ ultra-high temperature quartz crystal wafer 1 into the coating machine. Plate a chromium layer and a silver electrode layer on the upper and lower surfaces of the 200℃ ultra-high temperature quartz crystal wafer 1 to form electrodes and obtain the 200℃ ultra-high temperature quartz crystal oscillator 10 for later use. The electrode size for coating is manufactured according to the design requirements. An upper surface coating electrode 2 and a secondary electrode 4 are formed on the upper surface of the 200℃ ultra-high temperature quartz crystal wafer 1, and a lower surface coating electrode 3 and a secondary electrode 4 are formed on the lower surface. The upper surface coating electrode 2 and the lower surface coating electrode 3 are symmetrically distributed with respect to the midpoint on the upper and lower surfaces, respectively, and are both rectangular structures.

[0071] Phase Three: Fabrication of the 200℃ Ultra-High Temperature Oscillating Circuit 6

[0072] Step 1: Place the chip 9 and the base 8 into the automatic dispensing machine respectively, and use die bonder to bond the bottom of the chip 9 to the groove of the base 8. Remove and set aside.

[0073] Step 2: Place the base 8 with the chip 9 attached into the oven, set it to 150℃±10℃, bake for 50min±10min to solidify the chip 9 onto the base 8, and remove it for later use.

[0074] Step 3: Place the base 8 with chip 9 attached into the bonding machine, set the preheating temperature of the bonding machine to 160℃±10℃, and weld the pins of chip 9 to the conductive path 5 of base 8 with gold wire to obtain a 200℃ ultra-high temperature oscillation circuit 6 containing chip 9 and base 8, for later use.

[0075] Phase Four: Electrical Installation of Open Oscillator 7

[0076] Step 1: Place the 200℃ ultra-high temperature quartz crystal oscillator 10 and the 200℃ ultra-high temperature oscillation circuit 6 into the automatic film loading and dispensing machine respectively. Use the 200℃ ultra-high temperature conductive adhesive 12 to bond the 200℃ ultra-high temperature quartz crystal oscillator 10 to the 200℃ ultra-high temperature oscillation circuit 6, and then take it out for use.

[0077] Step 2: Place the 200℃ ultra-high temperature oscillation circuit 6, which is bonded with the 200℃ ultra-high temperature quartz crystal oscillator 10, onto the conveyor belt of the curing mesh belt oven. Set the first half to bake at 185℃±10℃ for more than 30 minutes and the second half to bake at 270±10℃ for more than 30 minutes. Fix the 200℃ ultra-high temperature quartz crystal oscillator 10 onto the 200℃ ultra-high temperature oscillation circuit 6 to obtain the open oscillator 7, and take it out for use.

[0078] Phase 5: Frequency tuning and baking of open oscillator 7

[0079] Step 1: Place the open oscillator 7 into the fine-tuning machine and use the ion etching frequency tuning method to fine-tune the frequency of the 200℃ ultra-high temperature quartz crystal oscillator 10. After fine-tuning, test according to the design parameters and set aside.

[0080] Step 2: Place the finely adjusted open oscillator 7 into a vacuum oven, set it to 150℃±3℃, and vacuum bake for at least 24 hours. Remove and set aside.

[0081] Phase Six: Packaging and Passivation of High-Temperature, High-Precision Quartz Crystal Oscillators

[0082] Step 1: Place the baked open oscillator 7 and sealing cover 11 into the sealing and welding machine. First, vacuum bake the open oscillator 7 at a temperature of 150℃±10℃ for 50 to 90 minutes. Then, seal the sealing cover 11 and the open oscillator 7 in a vacuum environment or a nitrogen-filled environment by high-frequency current parallel welding. After taking them out, print the markings to obtain a high-temperature resistant, high-precision quartz crystal oscillator for later use.

[0083] Step 2: Rough leak test. Using a pressurized airtightness test fluid, the high-temperature resistant and high-precision quartz crystal oscillator is subjected to a rough leak test. No obvious air bubbles are required. Then it is taken out for use.

[0084] Step 3: Reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use.

[0085] Step 4: Accelerate aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period ahead of time. Then, test it according to the design parameters and set it aside for later use.

[0086] Step 5: Helium leak detection. Place the high-temperature resistant, high-precision quartz crystal oscillator in an anti-static mesh, put it in a pressurized container, and pressurize it with 99.99% high-purity helium gas for at least 2 hours at a pressure of 0.4–0.6 MPa. Then, place it in a helium mass spectrometer leak detector for helium leak detection. The leak rate must not exceed 5 × 10⁻⁶. -3 Pa.cm 3 The standard is / s, then retrieve it for later use;

[0087] Step Six: Temperature Shock. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into a temperature shock chamber. Set the temperature to -65℃±3℃ and +200℃±3℃ for 10 cycles of shock to test the reliability, stability, and durability of the product under different temperatures. Then, test it according to the design parameters and set it aside for later use.

[0088] Step 7: Secondary reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use.

[0089] Step 8: Secondary accelerated aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period in advance. Then, test it according to the design parameters and set it aside for later use.

[0090] Step 9: Room temperature test. Under normal temperature conditions of 25℃±3℃, conduct the test according to the design parameters and set aside for later use.

[0091] Step 10: High and low temperature test. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray, put it into a temperature measuring machine, set the operating temperature range to -65℃ to +200℃, test the electrical performance parameters of the product, and then remove it for later use.

[0092] Based on the above description, the manufacturing method of the high-temperature resistant and high-precision quartz crystal oscillator of the present invention solves the problem of the lack of manufacturing process methods for high-temperature resistant and high-precision quartz crystal oscillators. It can achieve mass production with a high degree of automation. At the same time, the manufactured products can meet the requirements of wide temperature and high temperature operating environments from -65℃ to +200℃, realizing a wide temperature operating range and high temperature and high precision frequency output functions. The parameters are consistent and the cost is not increased compared with traditional quartz crystal oscillators.

[0093] The above embodiments are merely one implementation method of the present invention and are only used to help understand the method and core idea of ​​the present invention. They should not be used to limit the scope of protection of the present invention. Any modifications or refinements made without departing from the idea and spirit of the present invention, which solve technical problems consistent with the present invention, should be included within the scope of protection of the present invention.

Claims

1. A method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator, characterized in that, Includes the following stages: Phase 1: Fabrication of 200℃ Ultra-High Temperature Quartz Wafer (1) First, the quartz crystal block is ground and cut into long strip quartz crystal rods. Then, the rods are chamfered and cut into long strip quartz wafers according to the AT cutting type of 36°±20′. Then, they are ground and cut into quartz wafer blanks. Through grinding, high temperature washing and corrosion, 200℃ ultra-high temperature quartz wafers (1) are obtained for later use. The obtained 200℃ ultra-high temperature quartz wafers (1) are rectangular with a length-to-width-to-thickness ratio greater than 10. Phase Two: Fabrication of a 200℃ Ultra-High Temperature Quartz Crystal Oscillator (10) The 200℃ ultra-high temperature quartz wafer (1) was cleaned, arranged, cleaned a second time and coated to obtain the 200℃ ultra-high temperature quartz crystal oscillator (10) for later use; Phase 3: Fabrication of the 200℃ Ultra-High Temperature Oscillating Circuit (6) First, the chip (9) and the base (8) are fixed together with die bond adhesive. After curing, the pins of the chip (9) are welded to the conductive path (5) of the base (8) with gold wire to obtain a 200℃ ultra-high temperature oscillation circuit (6) containing the chip (9) and the base (8) for later use. Phase 4: Electrical installation of open oscillator (7) First, the 200℃ ultra-high temperature quartz crystal oscillator (10) and the 200℃ ultra-high temperature oscillation circuit (6) are bonded together with the 200℃ ultra-high temperature conductive adhesive (12), and then cured to obtain an open oscillator (7) for later use; Phase 5: Frequency tuning and baking of open oscillator (7) First, fine-tune the open oscillator (7) to obtain the required frequency, and then bake it at high temperature and take it out for use. Phase Six: Packaging and Passivation of High-Temperature, High-Precision Quartz Crystal Oscillators First, the open oscillator (7) and the sealing cover (11) are sealed together and printed to obtain a high-temperature resistant and high-precision quartz crystal oscillator. Then, the high-temperature resistant and high-precision quartz crystal oscillator is passivated and re-passivated, including rough leak detection, reflow soldering, accelerated aging, helium leak detection, temperature shock, secondary reflow soldering, secondary accelerated aging, room temperature test, and high and low temperature test to obtain a qualified high-temperature resistant and high-precision quartz crystal oscillator. The packaging and passivation of high-temperature resistant, high-precision quartz crystal oscillators includes the following steps: Step 1: Place the baked open oscillator (7) and sealing cover (11) into the sealing and welding machine. First, vacuum bake the open oscillator (7) at a temperature of 150℃±10℃ for 50 to 90 minutes. Then, seal the sealing cover (11) and open oscillator (7) in a vacuum environment or a nitrogen-filled environment by high-frequency current parallel welding. After taking them out, print them to obtain a high-temperature resistant and high-precision quartz crystal oscillator for later use. Step 2: Rough leak test. Using a pressurized airtightness test fluid, the high-temperature resistant and high-precision quartz crystal oscillator is subjected to a rough leak test. No obvious air bubbles are required. Then it is taken out for use. Step 3: Reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use. Step 4: Accelerate aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period ahead of time. Then, test it according to the design parameters and set it aside for later use. Step 5: Helium leak detection. Place the high-temperature resistant, high-precision quartz crystal oscillator in an anti-static mesh, put it in a pressurized container, and pressurize it with 99.99% high-purity helium gas for at least 2 hours at a pressure of 0.4–0.6 MPa. Then, place it in a helium mass spectrometer leak detector for helium leak detection. The leak rate must not exceed 5*10^6 ppm. -3 pa.cm 3 The standard is / s, then retrieve it for later use; Step Six: Temperature Shock. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into a temperature shock chamber. Set the temperature to -65℃±3℃ and +200℃±3℃, and perform 10 cycles of shock to test the reliability, stability, and durability of the product under different temperatures. Then, conduct tests according to the design parameters and set it aside for later use. Step 7: Secondary reflow soldering. Place the high-temperature resistant, high-precision quartz crystal oscillator in the tray and put it into the reflow soldering machine. Set eight temperature zones: 180℃, 220℃, 300℃, 310℃, 330℃, 330℃, and 330℃, with an allowable temperature variation of ±10℃. Set the conveyor speed to 10min ±10s. After two consecutive high-temperature reflow soldering tests, perform testing according to the design parameters and set aside for later use. Step 8: Secondary accelerated aging. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray and put it into an aging oven. Set the oven to 125℃±10℃ / 72h or 200℃±10℃ / 24h to release and eliminate residual stress from the processing of the high-temperature resistant, high-precision quartz crystal oscillator, allowing the product to enter the stabilization period in advance. Then, test it according to the design parameters and set it aside for later use. Step 9: Room temperature test. Under normal temperature conditions of 25℃±3℃, conduct the test according to the design parameters and set aside for later use. Step 10: High and low temperature test. Place the high-temperature resistant, high-precision quartz crystal oscillator in a tray, put it into a temperature measuring machine, set the operating temperature range to -65℃ to +200℃, test the electrical performance parameters of the product, and then remove it for later use.

2. The method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator according to claim 1, characterized in that, The fabrication of a 200℃ ultra-high temperature quartz wafer (1) includes the following steps: Step 1: Take quartz crystal block raw material, grind the X and Z surfaces of the quartz crystal block and cut it into strips using a multi-wire cutting machine to form quartz crystal rods for later use; Step 2: Chamfer the four sides of the cut quartz crystal rod, check the X and Z face angles and chamfer dimensions of the quartz crystal rod, and set aside for later use; Step 3: Place the quartz crystal rod into a multi-wire dicing machine, select the AT cutting angle, and slice the crystal at 36°±20′ to form long strip quartz wafers. Detect the angle of the long strip quartz wafers and set them aside. Step 4: Grind the long quartz wafers through multiple passes with different grits to achieve the desired thickness, grit, and X-side dimensions. Then, cut the wafers into slices using a multi-wire cutter. Finally, grind the Z-side of the original quartz wafers to the desired dimensions and set them aside. Step 5: The original quartz wafer is chemically washed at high temperature, and then the original quartz wafer is processed by frequency etching with chemical agents. Finally, the frequency is sorted to obtain a quartz wafer (1) that can withstand ultra-high temperature of 200℃, which is ready for use. It has a parallel upper surface and a lower surface. The quartz wafer (1) that can withstand ultra-high temperature of 200℃ is equipped with a fault-proof structure, including the length direction of the wafer as the first direction.

3. The method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator according to claim 1, characterized in that, The fabrication of a 200℃ ultra-high temperature quartz crystal oscillator (10) includes the following steps: Step 1: Place the 200℃ ultra-high temperature quartz wafer (1) in a cleaning basket, clean it through a six-step process using an ultrasonic cleaner and a special cleaning solution, and then put it into an oven at 150℃±10℃ for 30 to 60 minutes to dry it. After drying, it is ready for use. Step 2: Place the cleaned 200℃ ultra-high temperature quartz wafer (1) flat in the tray of the automatic wafer sorting machine. Select undamaged 200℃ ultra-high temperature quartz wafer (1) through the automatic wafer sorting machine and transfer it to the coating fixture. After the coating fixture is full, remove it and install the cover plate for later use. Step 3: Place the coating fixture containing the 200℃ ultra-high temperature quartz wafer (1) in the cleaning basket, and perform the second cleaning process of six steps using the special cleaning solution of the ultrasonic cleaner. Then, put it into the oven at 150℃±10℃ for 30 to 60 minutes to dry. After drying, it is ready for use. Step 4: Place the coating fixture containing the 200℃ ultra-high temperature quartz crystal wafer (1) into the coating machine. Plate a chromium layer and a silver electrode layer on the upper and lower surfaces of the 200℃ ultra-high temperature quartz crystal wafer (1) to form electrodes and obtain a 200℃ ultra-high temperature quartz crystal oscillator (10) for later use. The electrode size of the coating is made according to the design requirements. An upper surface coating electrode (2) and a secondary electrode (4) are formed on the upper surface of the 200℃ ultra-high temperature quartz crystal wafer (1), and a lower surface coating electrode (3) and a secondary electrode (4) are formed on the lower surface. The upper surface coating electrode (2) and the lower surface coating electrode (3) are symmetrically distributed on the upper and lower surfaces with respect to the midpoint, respectively, and are all rectangular structures.

4. The method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator according to claim 1, characterized in that, The fabrication of the 200℃ ultra-high temperature oscillation circuit (6) includes the following steps: Step 1: Place the chip (9) and the base (8) into the automatic dispensing machine respectively, and use die bonder to bond the bottom of the chip (9) to the groove of the base (8), and take it out for later use; Step 2: Place the base (8) with the chip (9) attached into the oven, set it to 150℃±10℃, bake for 50min±10min to solidify the chip (9) onto the base (8), and take it out for later use; Step 3: Place the substrate (8) with the chip (9) bonded on it into the bonding machine, set the preheating temperature of the bonding machine to 160℃±10℃, and weld the pins of the chip (9) to the conductive path (5) of the substrate (8) through gold wire to obtain a 200℃ ultra-high temperature oscillation circuit (6) containing the chip (9) and the substrate (8) for later use.

5. The method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator according to claim 1, characterized in that, The electrical assembly of the open oscillator (7) includes the following steps: Step 1: Place the 200℃ ultra-high temperature quartz crystal oscillator (10) and the 200℃ ultra-high temperature oscillation circuit (6) into the automatic film loading and dispensing machine respectively, and use the 200℃ ultra-high temperature conductive adhesive (12) to bond the 200℃ ultra-high temperature quartz crystal oscillator (10) to the 200℃ ultra-high temperature oscillation circuit (6), and take it out for later use; Step 2: Place the 200℃ ultra-high temperature oscillation circuit (6) with the 200℃ ultra-high temperature quartz crystal oscillator (10) bonded to it onto the conveyor belt of the curing mesh belt oven. Set the first half to bake at 185℃±10℃ for more than 30 minutes and the second half to bake at 270±10℃ for more than 30 minutes. Fix the 200℃ ultra-high temperature quartz crystal oscillator (10) onto the 200℃ ultra-high temperature oscillation circuit (6) to obtain an open oscillator (7), and take it out for use.

6. The method for manufacturing a high-temperature resistant, high-precision quartz crystal oscillator according to claim 1, characterized in that, The tuning and baking of the open oscillator (7) includes the following steps: Step 1: Place the open oscillator (7) into the fine-tuning machine and use the ion etching frequency tuning method to fine-tune the frequency of the 200℃ ultra-high temperature quartz crystal oscillator (10). After fine-tuning, test according to the design parameters and set aside for later use. Step 2: Place the finely adjusted open oscillator (7) into a vacuum oven, set it to 150℃±3℃, and vacuum bake for more than 24 hours. Remove and set aside.

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