A high temperature sensitive thermistor crystal resonator

Abstract

The present invention relates to a high temperature sensitivity thermistor crystal resonator, comprising a quartz base, a thermistor, a quartz lower cover and a quartz upper cover, the quartz base comprising a quartz wall and a quartz chip, the quartz wall having a through hole, the upper and lower ends of the quartz wall being respectively sealed by the quartz upper cover and the quartz lower cover, a platform being provided on one side of the lower part of the through hole, a thermistor being mounted on the platform, a quartz chip being suspended on the other side of the through hole, a clamping part being provided in the middle of the front and rear sides of the quartz chip, each clamping part being respectively connected to the corresponding inner wall of the through hole, and an external electrode being respectively connected to the quartz chip and the thermistor in one-to-one correspondence at the bottom of the quartz lower cover. The present invention can reduce the thermal stress of the thermistor crystal resonator, improve the anti-aging ability of the resonator, and provide an accurate real-time temperature signal, so as to achieve the purpose of stable operation in a harsh temperature environment.

Description

Technical Field

[0001] The invention relates to the technical field of quartz crystal frequency components, in particular to a high temperature-sensitivity thermistor crystal resonator. Background Art

[0002] Thermistor crystal resonator is usually composed of piezoelectric quartz chip, thermistor, conductive glue, ceramic base and metal cover. The piezoelectric quartz chip is usually rectangular or circular, and the package base usually needs to reserve a groove for thermistor. The piezoelectric quartz chip is plated with electrodes on the upper and lower sides and fixed in the package shell by conductive glue. The electrodes are connected to the base pins of the package shell through the leads of the sealed package. The AC voltage is connected to the upper and lower electrodes of the quartz chip through the pins, causing the quartz chip to produce an inverse piezoelectric effect, thereby generating oscillation. At the same time, the thermistor senses the surrounding temperature and transmits the temperature signal to the IC. The IC adjusts the frequency output of the crystal oscillation circuit in time through the internal circuit to stabilize it within a controllable range.

[0003] With the continuous development of microelectronic products, stringent requirements have been put forward for thermistor crystal resonators. First, the materials of the base and the upper cover are different, which will produce greater thermal stress during the thermal process; secondly, the chip is fixed to the base with conductive glue, which can easily release small molecules at high temperatures, affecting the product's anti-aging ability; finally, the thermistor and the base are designed separately in different grooves, which makes the thermistor sense temperature and the quartz chip with a certain lag. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a high temperature sensitivity thermistor crystal resonator, which can reduce the thermal stress of the thermistor crystal resonator, while improving the anti-aging ability of the resonator and providing accurate real-time temperature signals, so as to achieve the purpose of stable operation in harsh temperature environments.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to provide a high temperature sensitivity thermistor crystal resonator, including a quartz base, a thermistor, a quartz lower cover and a quartz upper cover, the quartz base includes a quartz wall and a quartz chip, the quartz wall has a through hole, the upper and lower ends of the quartz wall are respectively sealed by the quartz upper cover and the quartz lower cover, one side of the lower part of the through hole is provided with a platform, the thermistor is installed on the platform, the other side of the through hole is suspended with a quartz chip, the middle of the front and rear sides of the quartz chip are provided with a clamping part, each clamping part is respectively connected to the corresponding inner wall of the through hole, and the bottom of the quartz lower cover is provided with external electrodes respectively connected to the quartz chip and the thermistor in a one-to-one correspondence.

[0006] As a supplement to the technical solution described in the present invention, the clamping part is an isosceles trapezoidal block structure, and the height of the clamping part gradually increases from one end where the clamping part is connected to the quartz chip to the other end where the clamping part is connected to the inner wall of the through hole.

[0007] As a supplement to the technical solution described in the present invention, the quartz wall, quartz chip, platform and clamping part are all formed by etching the quartz base as a whole.

[0008] As a supplement to the technical solution described in the present invention, two connecting electrode parts are arranged in parallel on the platform, the thermistor is mounted on the two connecting electrode parts through solder paste, and the two connecting electrode parts are respectively connected to corresponding external electrodes.

[0009] As a supplement to the technical solution described in the present invention, a circle of convex rings are arranged around the opening at the upper and lower ends of the quartz wall, and the convex rings and the end faces of the quartz wall form a step structure. The upper end of the quartz lower cover and the lower end of the quartz upper cover are both provided with boss structures inserted into the corresponding convex rings.

[0010] As a supplement to the technical solution described in the present invention, the quartz wall and the quartz lower cover as well as the quartz wall and the quartz upper cover are sealed by means of a gold-tin alloy.

[0011] As a supplement to the technical solution described in the present invention, the distance between the thermistor and the quartz chip ranges from 90 to 100 um.

[0012] As a supplement to the technical solution described in the present invention, the upper and lower surfaces of the quartz chip are all covered with a layer of electrode surface, which overlaps with the upper surface or the lower surface of the quartz chip to form a main vibration area, and the two electrode surfaces are respectively connected to the corresponding external electrodes.

[0013] As a supplement to the technical solution described in the present invention, an electrode foot is provided on each electrode surface, the electrode foot of the upper electrode surface is arranged along the upper surface of one of the clamping parts, and the electrode foot of the lower electrode surface is arranged along the lower surface of the other clamping part, and the electrode feet of each of the two electrode surfaces are respectively connected to the corresponding external electrodes.

[0014] As a supplement to the technical solution described in the present invention, an upper electrode portion is extended and arranged at the four corners of the upper end of the quartz lower cover, and the four upper electrode portions are respectively connected to the quartz chip and the thermistor one by one. An external electrode is installed at the four corners of the lower end of the quartz lower cover, and a conductive hole is arranged inside the quartz lower cover between the upper and lower adjacent upper electrode portions and the external electrode, and the conductive hole is filled with a conductive material.

[0015] Beneficial effects: The present invention relates to a high temperature sensitive thermistor crystal resonator. A quartz chip is etched out on a quartz base through an etching process and connected to a quartz wall through a clamping part, and only the oscillation area of ​​the electrode surface of the quartz chip is retained, which can effectively reduce the oscillation energy loss of the quartz chip; at the same time, no conductive glue is needed to fix the quartz chip, which can effectively improve the anti-aging ability of the resonator; a platform is etched in the lower part of the quartz base through an etching process, and a thermistor is directly built into the platform inside the quartz base, which can greatly reduce the thickness of the base; by designing the thermistor and the quartz chip in the same cavity, the crystal can be accurately measured. The real-time temperature of the quartz chip provides accurate temperature data for IC compensation; through the optimization of the base and the upper and lower cover structures, the upper and lower ends of the quartz wall are designed into a stepped structure, and the quartz upper cover and the quartz lower cover are designed with a boss structure matching the stepped structure, which can effectively improve the positioning accuracy between the quartz wall and the quartz lower cover, as well as between the quartz wall and the quartz upper cover, and improve their welding strength; by designing the base, upper cover and lower cover of the resonator to be made of silicon dioxide, which is the same material as the quartz chip, the thermal stress of the product can be effectively reduced, and the high temperature resistance of the thermistor can be greatly improved to meet the customer's demanding use environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional view of the main viewing direction of the present invention;

[0017] Figure 2 It is a top view of the present invention after removing the quartz upper cover and the quartz lower cover;

[0018] Figure 3 The present invention Figure 2 Sectional view in the AA direction;

[0019] Figure 4 The present invention Figure 2 Cross-sectional view in the BB direction;

[0020] Figure 5 The present invention Figure 4 Schematic diagram after installing the quartz upper cover and quartz lower cover;

[0021] Figure 6 is a top view of the quartz lower cover of the present invention;

[0022] Figure 7 It is a bottom view of the quartz lower cover described in the present invention.

[0023] Illustration: 1. Quartz base, 2. Quartz wall, 3. Quartz chip, 4. Conductive hole, 5. Connecting electrode part, 6. Solder paste, 7. Thermistor, 8. Through hole, 9. Quartz lower cover, 10. Clamping part, 11. Platform, 12. Raised ring, 13. External electrode, 14. Boss structure, 15. Quartz upper cover, 16. Gold-tin alloy, 17. Upper electrode part, 31. Electrode surface, 32. Electrode foot. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0025] An embodiment of the present invention relates to a high temperature sensitivity thermistor crystal resonator, such as Figure 1-7 As shown, it includes a quartz base 1, a thermistor 7, a quartz lower cover 9 and a quartz upper cover 15. The quartz base 1 includes a quartz wall 2 and a quartz chip 3. The quartz wall 2 has a through hole 8. The upper and lower ends of the quartz wall 2 are respectively sealed by the quartz upper cover 15 and the quartz lower cover 9. A platform 11 is provided on one side of the lower part of the through hole 8, and the thermistor 7 is installed on the platform 11. The quartz chip 3 is suspended on the other side of the through hole 8. The front and rear ends of the quartz chip 3 are A clamping portion 10 is provided in the middle of both sides, and each clamping portion 10 is connected to the inner wall of the corresponding through hole 8. The quartz chip 3 is connected to the quartz wall 2 through the clamping portion 10, replacing the traditional conductive glue to fix the chip. The conductive glue is the main source of outgas (i.e., removing gas by heating), which can effectively reduce outgas and improve the anti-aging ability of the product. The bottom of the quartz lower cover 9 is provided with external electrodes 13 respectively connected to the quartz chip 3 and the thermistor 7 in a one-to-one correspondence.

[0026] On the one hand, the present invention uses a unified quartz material (i.e., silicon dioxide material) for the base, the upper cover, and the lower cover, which greatly reduces the thermal stress of the product. At the same time, the quartz chip 3 is etched on the quartz base 1 through an etching process and connected to the quartz wall 2 through a clamping portion 10, and only the oscillation area of ​​the electrode surface of the quartz chip 3 is retained, which can effectively reduce the oscillation energy loss of the quartz chip 3; at the same time, no conductive glue is required to fix the quartz chip, which can effectively improve the anti-aging ability of the resonator; on the other hand, a platform 11 is etched in the lower part of the quartz base 1 through an etching process, and the thermistor 7 is directly built into the platform 11 inside the quartz base 1, which can greatly reduce the thickness of the base. At the same time, the thermistor 7 and the quartz chip 3 are designed in the same cavity (i.e., in the through hole 8), so that the real-time temperature signal of the quartz chip 3 can be accurately obtained, and an accurate temperature signal can be provided for the IC to achieve the effect of accurate compensation. In summary, the present invention can reduce the thermal stress of the thermistor crystal resonator, improve the anti-aging ability of the resonator, and provide an accurate real-time temperature signal, so as to achieve a product design that can work stably in a high temperature environment.

[0027] The traditional quartz chip 3 is fixed on the base by conductive glue. Due to the structure, fine-tuning can only scrape the electrode surface on one side, which will cause the thickness of the two electrode surfaces to be inconsistent after fine-tuning. At the same time, it will cause uneven thermal stress and slight deformation of the quartz chip 3, which will eventually lead to a large change in FL due to thermal shock (poor reflow ability). The present invention sets the quartz chip 3 in the air, which has the following advantages: fine-tuning can scrape the electrode surface on both sides, the thickness of the electrode surfaces on both sides is consistent after fine-tuning, and the thermal stress generated by the upper and lower electrode surfaces is uniform, which effectively improves the reflow ability of the product. Moreover, the quartz chip 3 is not in contact with the quartz wall 2 on all sides, and is only indirectly connected to the inner wall of the quartz wall 2 through two clamping parts 10.

[0028] As a preferred embodiment of the clamping portion 10, the clamping portion 10 is an isosceles trapezoidal block structure, and the height of the clamping portion 10 gradually increases from one end where the clamping portion 10 is connected to the quartz chip 3 toward the other end where the clamping portion 10 is connected to the inner wall of the through hole 8. Such a shape design of the clamping portion 10 can avoid concentrated stress when the product undergoes thermal shock or mechanical shock, effectively avoiding stress concentration while improving the structural strength of the product.

[0029] As a structural description of the quartz base 1, the quartz wall 2, quartz chip 3, platform 11 and clamping part 10 are all etched from the quartz base 1 as a whole. This structure formed by integrally processing a piece of quartz material can not only ensure the connection strength and structural stability between the components, but also effectively reduce thermal stress, greatly improving the high temperature resistance of the thermistor crystal resonator.

[0030] As an illustration of the installation method of the thermistor 7, two connecting electrode parts 5 are arranged in parallel on the platform 11, and the thermistor 7 is mounted on the two connecting electrode parts 5 through solder paste 6, and the two connecting electrode parts 5 are respectively connected to the corresponding external electrodes 13; the connecting electrode parts 5 are also directly processed on the platform 11 through an etching process.

[0031] As an installation instruction for the quartz lower cover 9 and the quartz upper cover 15, a convex ring 12 is arranged around the opening at the upper and lower ends of the quartz wall 2, and the convex ring 12 forms a step structure with the end face of the quartz wall 2. The upper end of the quartz lower cover 9 and the lower end of the quartz upper cover 15 are provided with a boss structure 14 inserted into the corresponding convex ring 12; the quartz wall 2 and the quartz lower cover 9, as well as the quartz wall 2 and the quartz upper cover 15 are sealed by a gold-tin alloy 16; high-precision positioning is achieved by the cooperation of the boss structure 14 and the step structure At the same time, this structure can also improve the welding strength. After positioning, sealing is achieved through the gold-tin alloy 16; the height of the gold-tin alloy 16 is 10~12um; the quartz upper cover 15 is a quartz plate, and the thickness of the quartz upper cover 15 is 60~70um; the quartz lower cover 9 is a quartz plate, and the thickness of the quartz lower cover 9 is 60~70um; the quartz base 1 is a quartz material, and the thickness of the quartz base 1 is 0.4~0.42mm; the total thickness of the resonator is 0.52~0.56mm.

[0032] As an explanation of the arrangement of the thermistor 7 and the quartz chip 3 , the spacing between the thermistor 7 and the quartz chip 3 is in the range of 90 to 100 um. Within this spacing range, the real-time temperature signal of the quartz chip 3 can be relatively close to being sensed, while reducing the interference of the thermistor 7 with the quartz chip 3 .

[0033] As a preferred embodiment of the quartz chip 3, the upper and lower surfaces of the quartz chip 3 are all covered with a layer of electrode surface 31, and the electrode surface 31 overlaps with the upper surface or the lower surface of the quartz chip 3 to form a main vibration zone, and the two electrode surfaces 31 are respectively connected to the corresponding external electrodes 13; the advantages of using the electrode surface 31 to completely cover the chip are as follows: the oscillation area of ​​the quartz crystal resonator is the main vibration zone, that is, the part where the electrode surface overlaps with the surface of the quartz chip. In order to facilitate the plating of the electrode surface, part of the traditional quartz chip will not be covered with the electrode surface. When the quartz crystal vibrates, the energy will diffuse to the part not covered with the electrode surface, causing energy loss. The present invention connects the quartz chip 3 and the quartz wall 2 together, which can achieve only retaining the main vibration zone, forming an energy locking effect, reducing energy loss during vibration, and effectively reducing the resonator impedance.

[0034] An upper electrode portion 17 is extended and arranged at the four corners of the upper end of the quartz lower cover 9, and the four upper electrode portions 17 are respectively connected to the quartz chip 3 and the thermistor 7 in a one-to-one correspondence. An external electrode 13 is installed at the four corners of the lower end of the quartz lower cover 9. A conductive hole 4 is provided inside the quartz lower cover 9 between the upper and lower adjacent upper electrode portions 17 and the external electrode 13, and the conductive hole 4 is filled with a conductive material.

[0035] An electrode foot 32 is provided on each electrode surface 31. The electrode foot 32 of the upper electrode surface 31 is arranged along the upper surface of one of the clamping parts 10, and the electrode foot 32 of the lower electrode surface 31 is arranged along the lower surface of the other clamping part 10. The electrode feet 32 ​​of the two electrode surfaces 31 are respectively connected with the corresponding two upper electrode parts 17; the setting of the clamping part 10 can also be used to guide the arrangement of the electrode feet 32, simplifying the arrangement difficulty; the clamping part 10 on which the electrode feet 32 ​​are arranged on the upper surface has a conductive hole 4 opened inside, and the conductive hole 4 is filled with conductive material, and the electrode feet 32 ​​on the upper surface are connected with the corresponding upper electrode part 17 through the conductive hole 4 and the conductive material; the electrode feet 32 ​​on the lower surface can be directly connected with the upper electrode part 17.

[0036] by Figure 1 As a reference, the left and right directions of the quartz wall 2 are the length directions of the resonator, and the front and back directions of the quartz wall 2 are the width directions of the resonator; the setting direction of the electrode pin 32 is improved: the quartz crystal resonator uses a thickness shear oscillation mode, and when the crystal vibrates, the wave propagates along the X direction (i.e., the length direction of the resonator); the traditional electrode pin design is on the short side (i.e., the width direction of the resonator), and the silver glue fixes the chip while hindering the propagation of the wave. The present invention designs the electrode pin 32 on the long side (i.e., the electrode pin 32 is set on the clamping part 10, and the two clamping parts 10 are respectively connected to the front and rear inner walls of the quartz wall 2), and the wave will not be hindered when propagating along the X side, which effectively reduces the resonance impedance and improves the hysteresis ability of the quartz crystal.

[0037] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or components referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0038] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0039] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0040] The above is a detailed introduction to a high temperature sensitivity thermistor crystal resonator provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A high temperature sensitivity thermistor crystal resonator, comprising a quartz base (1), a thermistor (7), a quartz lower cover (9) and a quartz upper cover (15), characterized in that: The quartz base (1) comprises a quartz wall (2) and a quartz chip (3), wherein the quartz wall (2) has a through hole (8), and the upper and lower ends of the quartz wall (2) are respectively sealed by a quartz upper cover (15) and a quartz lower cover (9), a platform (11) is provided on one side of the lower part of the through hole (8), and a thermistor (7) is mounted on the platform (11), and a quartz chip (3) is suspended on the other side of the through hole (8), and a clamping portion (10) is provided in the middle of the front and rear sides of the quartz chip (3), and each clamping portion (10) is respectively connected to the inner wall of the corresponding through hole (8), and the bottom of the quartz lower cover (9) is provided with external electrodes (13) respectively connected to the quartz chip (3) and the thermistor (7) in a one-to-one correspondence.

2. A high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: The clamping portion (10) is an isosceles trapezoidal block structure, and the height of the clamping portion (10) gradually increases from one end where the clamping portion (10) is connected to the quartz chip (3) toward the other end where the clamping portion (10) is connected to the inner wall of the through hole (8).

3. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: The quartz wall (2), quartz chip (3), platform (11) and clamping portion (10) are all formed by etching the quartz base (1) as a whole.

4. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: Two connecting electrode parts (5) are arranged in parallel on the platform (11); the thermistor (7) is mounted on the two connecting electrode parts (5) via solder paste (6); and the two connecting electrode parts (5) are respectively connected to corresponding external electrodes (13).

5. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: A convex ring (12) is arranged around the opening at both the upper and lower ends of the quartz wall (2), and the convex ring (12) and the end surface of the quartz wall (2) form a stepped structure. The upper end of the quartz lower cover (9) and the lower end of the quartz upper cover (15) are both provided with a boss structure (14) inserted into the corresponding convex ring (12).

6. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: The quartz wall (2) and the quartz lower cover (9) as well as the quartz wall (2) and the quartz upper cover (15) are sealed by means of a gold-tin alloy (16).

7. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: The distance between the thermistor (7) and the quartz chip (3) is in the range of 90 to 100 um.

8. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: The upper and lower surfaces of the quartz chip (3) are completely covered with a layer of electrode surface (31), and the electrode surface (31) overlaps with the upper surface or the lower surface of the quartz chip (3) to form a main vibration area. The two electrode surfaces (31) are respectively connected to the corresponding external electrodes (13).

9. The high temperature sensitivity thermistor crystal resonator according to claim 8, characterized in that: An electrode foot (32) is provided on each electrode surface (31); the electrode foot (32) of the upper electrode surface (31) is arranged along the upper surface of one of the clamping parts (10); the electrode foot (32) of the lower electrode surface (31) is arranged along the lower surface of the other clamping part (10); and the electrode feet (32) of each of the two electrode surfaces (31) are respectively connected to the corresponding external electrode (13).

10. The high temperature sensitivity thermistor crystal resonator according to claim 1, characterized in that: An upper electrode portion (17) is extended and arranged at each of the four corners of the upper end of the quartz lower cover (9), and the four upper electrode portions (17) are respectively connected to the quartz chip (3) and the thermistor (7) in a one-to-one correspondence. An external electrode (13) is installed at each of the four corners of the lower end of the quartz lower cover (9), and a conductive hole (4) is provided inside the quartz lower cover (9) between the upper and lower adjacent upper electrode portions (17) and the external electrode (13), and the conductive hole (4) is filled with a conductive material.

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