Crystal oscillator package structure

Abstract

The application relates to a crystal oscillator packaging structure, which comprises a bottom base, a resonant crystal sheet, two arc-shaped metal blocks, two first metal coatings, a top cover and a second metal coating; a mounting groove is arranged in the middle of the top surface of the bottom base; the resonant crystal sheet is arranged in the mounting groove, and the resonant crystal sheet comprises a frame area, a resonant area and two U-shaped connecting areas; the two first metal coatings are arranged on the upper surfaces of the two horizontal connecting areas respectively; the top cover is sealed and packaged with the bottom base; and the second metal coating is arranged on the bottom surface of the top cover. The two arc-shaped metal blocks and the two first metal coatings are connected with each other to form a closed shielding ring surrounding the resonant area, and the closed shielding ring and the second metal coating form a shielding cavity surrounding the resonant area, so that the external electromagnetic interference is effectively isolated. The first sealing ring and the second sealing ring form two layers of staggered sealing, so that the invasion path of the water vapor is multidirectional and three-dimensional ladder-shaped, the invasion path is complex and long, and the sealing performance of the crystal oscillator packaging structure is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of crystal oscillator packaging technology, and in particular relates to a crystal oscillator packaging structure. Background Technology

[0002] Quartz crystal oscillators are core frequency reference components in electronic devices, and the reliability and stability of their packaging structure directly affect the performance and lifespan of the entire system, especially in demanding fields such as communications, industrial control, and automotive electronics. While common crystal oscillator packaging structures on the market have addressed frequency drift caused by mechanical vibration to some extent, they still exhibit significant limitations when facing increasingly demanding application environments—such as high temperature, high humidity, and strong electromagnetic interference.

[0003] In existing technologies, such as the crystal oscillator packaging structure disclosed in Chinese patent application publication number CN113965184A, a U-shaped horizontal connection area is used to achieve a flexible connection between the resonant region and the frame region, which helps to reduce the impact of external mechanical vibration on the resonant region, thereby improving frequency stability. However, this type of structure still has two major drawbacks:

[0004] First, there is a lack of effective electromagnetic shielding mechanisms. Due to the absence of a dedicated shielding structure, this type of packaging struggles to suppress external interference in complex electromagnetic environments, causing abnormal fluctuations in the resonant frequency and severely impacting the accuracy and stability of the output signal.

[0005] Secondly, the sealing performance is insufficient. Existing packaging typically relies on a simple planar sealing structure, that is, arranging a single or multiple planar sealing rings between the bottom base, the frame area, and the top cover. Once there are slight processing deviations or imperfections in the flatness of the relevant components, tiny gaps will be left at the sealing interface. These gaps become channels for the intrusion of moisture, dust, and other corrosive gases, which can lead to oxidation of the internal resonant electrodes, degradation of electrical performance, or even failure over time.

[0006] In summary, the shortcomings of existing crystal oscillator packaging technology in terms of sealing performance and electromagnetic compatibility have become key bottlenecks restricting its widespread application in harsh environments. Therefore, there is an urgent need to develop a crystal oscillator packaging structure that combines excellent sealing performance with high-strength electromagnetic shielding capabilities to meet the higher reliability requirements of modern high-end electronic equipment for frequency sources. Summary of the Invention

[0007] The main objective of this invention is to propose a crystal oscillator packaging structure that can effectively solve the problems in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A crystal oscillator packaging structure, comprising:

[0010] The bottom base has an installation groove in the center of its top surface;

[0011] A resonant crystal chip is placed in the mounting slot. The resonant crystal chip includes a frame area, a resonant area, and two U-shaped connection areas. The frame area is adapted to the mounting slot. The resonant area is located in the frame area. The two U-shaped connection areas are located on both sides of the resonant area. One end of each U-shaped connection area is connected to the resonant area, and the other end is connected to the frame area through a horizontal connection area.

[0012] Two arc-shaped metal blocks are fixed in the mounting groove and located outside the U-shaped connection area, with the two ends of the arc-shaped metal blocks abutting against the sidewalls of the two horizontal connection areas respectively;

[0013] Two first metal coatings are respectively disposed on the upper surfaces of the two horizontal connection areas to connect the two ends of the two arc-shaped metal blocks, so that the two arc-shaped metal blocks and the two first metal coatings are connected to each other to form a closed shielding ring surrounding the resonant area.

[0014] The top cover is fitted and sealed to the bottom base;

[0015] A second metal coating is applied to the bottom surface of the top cover. After the top cover is sealed and encapsulated with the bottom base, the second metal coating abuts against the closed shielding ring.

[0016] Preferably, the inner bottom of the mounting groove has a damping groove, and an elastic pad is installed in the damping groove. The elastic pad corresponds to the size and position of the resonant region, and the height of the elastic pad is slightly higher than the damping groove.

[0017] Preferably, the top edge of the sealing base is provided with a stepped sealing groove around the mounting groove. The stepped sealing groove is divided into an outer upper stepped groove and an inner lower stepped groove. A first sealing ring is provided in the upper stepped groove and a second sealing ring is provided in the lower stepped groove.

[0018] The bottom surface of the top cover has an annular sealing boss corresponding to the stepped sealing groove.

[0019] Preferably, the second metal coating is circular, with the same outer diameter as the arc-shaped metal block.

[0020] Preferably, it also includes:

[0021] Two signal pads are provided on the bottom surface of the sealing base;

[0022] Two grounding pads are provided on the bottom surface of the sealed base;

[0023] The first electrode layer is disposed on the top surface of the resonant region and the U-shaped connection region and the horizontal connection region on one side. The end of the first electrode layer is electrically connected to one of the signal pads through the resonant crystal chip and the metal via in the bottom base.

[0024] The second electrode layer is disposed on the bottom surface of the resonant region and the other side U-shaped connection region and horizontal connection region. The end of the second electrode layer is electrically connected to another signal pad through a metal via in the sealing base.

[0025] The two arc-shaped metal blocks are electrically connected to the two grounding pads through metal through holes in the bottom base.

[0026] Preferably, the ends of both the first electrode layer and the second electrode layer have isolation gaps from the closed shielding ring.

[0027] Preferably, conductive paste is applied to the contact surface between the closed shielding ring and the second metal coating.

[0028] Preferably, the arc-shaped metal block is fixed in the mounting groove by conductive epoxy resin.

[0029] Preferably, the frame area of ​​the resonant crystal chip is filled with damping gel between the frame area and the mounting groove.

[0030] Preferably, the bottom surface of the mounting slot is provided with one or more heat dissipation holes.

[0031] This invention provides a crystal oscillator packaging structure, which has the following beneficial effects.

[0032] 1. Two arc-shaped metal blocks and two first metal coatings are connected to form a closed shielding ring surrounding the resonant region. The closed shielding ring is used for grounding. After the top cover and the bottom base are fitted together and sealed, the second metal coating abuts against the closed shielding ring. The closed shielding ring and the second metal coating form a shielding cavity surrounding the resonant region, effectively isolating external electromagnetic interference and further improving the stability of the resonant frequency.

[0033] 2. The two ends of the arc-shaped metal block abut against the sidewalls of the two horizontal connection areas. The arc-shaped metal block not only forms part of the closed shielding ring but also provides lateral rigid support to the horizontal connection areas, limiting excessive deformation, enhancing structural stability, and ensuring the resonant area remains centered in the mounting slot, thus preventing instability in the resonant frequency due to structural deformation. The arc-shaped structural design is compatible with the U-shaped connection area, allowing for a semi-circular layout without cutting or splicing. Furthermore, the smooth, non-sharp surface of the arc structure effectively prevents electric field and stress concentration.

[0034] 3. The U-shaped connection area mainly absorbs horizontal vibration and impact energy, while the elastic pad mainly absorbs vertical vibration and impact energy. The two work together to absorb vibration and impact energy from different directions, thereby achieving multi-dimensional seismic protection for the resonant area.

[0035] 4. The upper and lower stepped grooves of the stepped sealing groove respectively accommodate the first and second sealing rings, forming two layers of staggered seals. This makes the intrusion path of water vapor multi-directional and three-dimensional stepped, with a complex and long intrusion path, which greatly improves the sealing performance of the crystal oscillator packaging structure. Attached Figure Description

[0036] Figure 1 This is an exploded view of the crystal oscillator packaging structure of the present invention.

[0037] Figure 2 This is a schematic diagram of the assembly of the bottom cover base and the resonant crystal chip of the present invention.

[0038] Figure 3 This is a schematic diagram of the top cover of the present invention.

[0039] Figure 4 This is a cross-sectional view of the crystal oscillator packaging structure of the present invention.

[0040] Figure 5 This is a schematic diagram of the water vapor intrusion path according to the present invention.

[0041] In the picture:

[0042] 1. Bottom sealing base; 11. Mounting groove; 12. Stepped sealing groove; 121. Upper stepped groove; 122. Lower stepped groove; 13. Signal pad; 14. Grounding pad; 15. Vibration damping groove;

[0043] 2. First sealing ring;

[0044] 3. Second sealing ring;

[0045] 4. Resonant crystal sheet; 41. Frame area; 42. Resonant area; 43. U-shaped connection area; 44. Horizontal connection area; 45. First electrode layer; 46. Second electrode layer;

[0046] 5. Top cover; 51. Annular sealing boss;

[0047] 6. Curved metal block;

[0048] 7. First metallic coating;

[0049] 8. Second metal coating;

[0050] 9. Elastic pad;

[0051] 10. Isolation gap. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0053] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0055] Reference Figure 1-4 The present invention provides a crystal oscillator packaging structure, comprising:

[0056] The bottom base 1 has an installation groove 11 in the middle of its top surface;

[0057] A resonant crystal chip 4 is placed in the mounting groove 11. The resonant crystal chip 4 includes a frame area 41, a resonant area 42, and two U-shaped connection areas 43. The frame area 41 is adapted to the mounting groove 11. The resonant area 42 is located in the frame area 41. The two U-shaped connection areas 43 are located on both sides of the resonant area 42. One end of each U-shaped connection area 43 is connected to the resonant area 42, and the other end is connected to the frame area 41 through a horizontal connection area 44.

[0058] Two arc-shaped metal blocks 6 are fixed in the mounting groove 11 and located outside the U-shaped connecting area 43. The two ends of the arc-shaped metal blocks 6 abut against the side walls of the two horizontal connecting areas 44 respectively.

[0059] Two first metal coatings 7 are respectively disposed on the upper surfaces of the two horizontal connection areas 44, for connecting the two ends of the two arc-shaped metal blocks 6, so that the two arc-shaped metal blocks 6 and the two first metal coatings 7 are connected to each other to form a closed shielding ring surrounding the resonant area 42.

[0060] The top cover 5 is fitted and sealed to the bottom base 1;

[0061] The second metal coating 8 is disposed on the bottom surface of the top cover 5. After the top cover 5 is sealed and encapsulated with the bottom base 1, the second metal coating 8 abuts against the closed shielding ring.

[0062] In this invention, the resonant crystal chip 4 is placed in the mounting groove 11, so that the bottom base 1 and the top cover 5 can directly contact each other for bonding and sealing, which helps to reduce the overall thickness of the crystal oscillator packaging structure.

[0063] Both sides of the resonant region 42 are connected to the frame region 41 through U-shaped connecting regions 43 and horizontal connecting regions 44. The U-shaped connecting regions and horizontal connecting regions 44 form a flexible transition section between the resonant region 42 and the frame region 41, rather than a rigid direct connection. When external vibration is transmitted to the frame region 41, the U-shaped connecting regions 43 will undergo slight bending, stretching or compressive deformation. During this process, the mechanical energy of the vibration is converted into the elastic potential energy of the structure, and then released through slight rebound, rather than being transmitted to the resonant region 42, thereby absorbing the vibration and impact energy, thus significantly attenuating the vibration intensity, effectively reducing the transmission of external mechanical vibration or instantaneous impact to the resonant region 42, and improving the stability of the resonant frequency.

[0064] While ensuring that the U-shaped connection area 43 absorbs vibration and impact energy, two arc-shaped metal blocks 6 are fixed in the mounting groove 11 and located outside the U-shaped connection area 43. The two ends of the arc-shaped metal blocks 6 abut against the side walls of the two horizontal connection areas 44 respectively. Two first metal coatings 7 are respectively provided on the upper surface of the two horizontal connection areas 44 to connect the two ends of the two arc-shaped metal blocks 6, so that the two arc-shaped metal blocks 6 and the two first metal coatings 7 are connected to each other to form a closed shielding ring surrounding the resonant area 42. The closed shielding ring is used for grounding. After the top cover 5 is sealed and encapsulated with the bottom base 1, the second metal coating 8 abuts against the closed shielding ring. The closed shielding ring and the second metal coating 8 form a shielding cavity surrounding the resonant area 42, effectively isolating external electromagnetic interference and further improving the stability of the resonant frequency.

[0065] Furthermore, in this invention, the arc-shaped metal block 6 is made of rigid metal. Both ends of the arc-shaped metal block 6 abut against the sidewalls of the two horizontal connection areas 44. The arc-shaped metal block 6 not only forms part of the closed shielding ring but also provides lateral rigid support to the horizontal connection areas 44, limiting excessive deformation of the horizontal connection areas 44, enhancing the structural stability of the horizontal connection areas 44, and ensuring that the resonant area 42 is always at the center of the mounting groove 11, avoiding instability in the resonant frequency due to structural deformation. The arc-shaped design is compatible with the U-shaped connection area 43, achieving a semi-circular layout without cutting or splicing. Simultaneously, the smooth curved surface without sharp corners of the arc shape effectively prevents electric field concentration and stress concentration.

[0066] As a preferred implementation scheme, refer to Figure 1 , Figure 2 The inner bottom of the mounting groove 11 has a shock-absorbing groove 15, and an elastic pad 9 is installed in the shock-absorbing groove 15. The elastic pad 9 corresponds to the size and position of the resonant area 42, and the height of the elastic pad 9 is slightly higher than the shock-absorbing groove 15.

[0067] The height of the elastic pad 9 is slightly higher than that of the damping groove 15. After the resonant crystal chip 4 is installed, the resonant area 42 squeezes the elastic pad 9 to put it in a slightly compressed state, so as to avoid vibration transmission caused by the rigid contact between the resonant area 42 and the bottom base 1. The elastic pad 9 provides elastic support for the resonant area 42. When external vibration or impact is transmitted to the bottom base 1, the elastic pad 9 absorbs energy through its own deformation (such as compression and rebound), further reducing the direct transmission of vibration to the resonant area 42.

[0068] To further explain, the U-shaped connection area 43 mainly absorbs the horizontal vibration and impact energy, while the elastic pad 9 mainly absorbs the vertical vibration and impact energy. The two work together to absorb vibration and impact energy from different directions, thereby achieving multi-dimensional seismic protection for the resonant area 42.

[0069] As a preferred implementation scheme, refer to Figure 1-3 The top edge of the sealing base 1 is provided with a stepped sealing groove 12 around the mounting groove 11. The stepped sealing groove 12 is divided into an outer stepped upper groove 121 and an inner stepped lower groove 122. A first sealing ring 2 is provided in the stepped upper groove 121 and a second sealing ring 3 is provided in the stepped lower groove 122.

[0070] The bottom surface of the top cover 5 has an annular sealing boss 51 corresponding to the stepped sealing groove 12.

[0071] Reference Figure 4-5The stepped upper groove 121 and stepped lower groove 122 of the stepped sealing groove 12 respectively accommodate the first sealing ring 2 and the second sealing ring 3, forming a two-layer staggered seal to replace the traditional planar seal. After the top cover 5 and the bottom base 1 are fastened and sealed, the annular sealing boss 51 squeezes the first sealing ring 2 and the second sealing ring 3, causing the first sealing ring 2 and the second sealing ring 3 to undergo plastic deformation. The first sealing ring 2 is in close contact with the two side walls of the stepped upper groove 121 and the annular sealing boss 51, and the second sealing ring 3 is also in close contact with the two side walls of the stepped lower groove 122 and the annular sealing boss 51. At the same time, the opposite surfaces of the first sealing ring 2 and the second sealing ring 3 are also in close contact with each other, so that the water vapor intrusion path is multi-directional and three-dimensional stepped, the intrusion path is complex and long, which greatly improves the sealing performance of the crystal oscillator packaging structure.

[0072] It should be further explained that the design of the stepped sealing groove 12 of the present invention combines the two grooves together, so that the first sealing ring 2 and the second sealing ring 3 can form a staggered seal while occupying a small area on the edge of the bottom base 1. The staggered sealing structure can be used alone or combined with the traditional planar seal, that is, the area on the top edge of the bottom base 1 other than the stepped sealing groove 12 is also sealed with a planar seal. This can achieve multiple seals and further improve the sealing effect of the crystal oscillator packaging structure.

[0073] As a preferred implementation scheme, refer to Figure 3 , Figure 2 The second metal coating 8 is circular, and its outer diameter is the same as that of the arc-shaped metal block 6.

[0074] After the top cover 5 and the bottom base 1 are sealed, the circular second metal coating 8 will precisely align with the edge of the closed shielding ring formed by the arc-shaped metal block 6 and the first metal coating 7 below, thus forming a complete, unbroken shielding cavity that completely encloses the resonant area 42 and ensures the shielding effect.

[0075] As a preferred implementation scheme, refer to Figure 2 The crystal oscillator package structure further includes: electrode wiring and external pin design.

[0076] Two signal pads 13 are disposed on the bottom surface of the sealing base 1;

[0077] Two grounding pads 14 are provided on the bottom surface of the sealing base 1;

[0078] The first electrode layer 45 is disposed on the top surface of the resonant region 42 and the U-shaped connection region 43 and the horizontal connection region 44 on one side. The end of the first electrode layer 45 is electrically connected to one of the signal pads 13 through the resonant crystal chip 4 and the metal via in the bottom base 1.

[0079] The second electrode layer 46 is disposed on the bottom surface of the resonant region 42 and the other side U-shaped connection region 43 and horizontal connection region 44. The end of the second electrode layer 46 is electrically connected to another signal pad 13 through a metal via in the bottom base 1.

[0080] The two arc-shaped metal blocks 6 are electrically connected to the two grounding pads 14 through metal through holes in the bottom base 1.

[0081] As a preferred implementation scheme, refer to Figure 2 The ends of the first electrode layer 45 and the second electrode layer 46 are both isolated from the closed shielding ring by a gap 10 to ensure good insulation between the high-frequency signal path and the ground shield, and to prevent signal leakage or short circuit.

[0082] As a preferred embodiment, conductive paste is applied to the contact surface between the closed shielding ring and the second metal coating 8. The conductive paste fills the microscopic unevenness of the contact surface, significantly reduces the contact resistance, improves the electrical connection quality, and thus enhances the overall electromagnetic isolation capability of the shielding cavity.

[0083] In a preferred embodiment, the arc-shaped metal block 6 is fixed in the mounting groove 11 by conductive epoxy resin. The conductive epoxy resin has both adhesive strength and conductivity, which can firmly fix the arc-shaped metal block 6 and provide a continuous electrical path, avoiding loosening or disconnection caused by vibration and ensuring the long-term stability of the shielding structure.

[0084] As a preferred embodiment, the frame area 41 of the resonant crystal chip 4 and the mounting groove 11 are filled with damping gel. The damping gel further absorbs the vibration energy transmitted by the frame area 41, achieving more comprehensive shock absorption and protection.

[0085] As a preferred embodiment, the bottom surface of the mounting groove 11 is provided with one or more heat dissipation holes to establish a heat convection channel for heat dissipation of the resonant crystal chip 4, so that it can maintain frequency stability under high power or high temperature environment.

[0086] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A crystal oscillator packaging structure, characterized in that, include: The bottom base has an installation groove in the center of its top surface; A resonant crystal chip is placed in the mounting slot. The resonant crystal chip includes a frame area, a resonant area, and two U-shaped connection areas. The frame area is adapted to the mounting slot. The resonant area is located in the frame area. The two U-shaped connection areas are located on both sides of the resonant area. One end of each U-shaped connection area is connected to the resonant area, and the other end is connected to the frame area through a horizontal connection area. Two arc-shaped metal blocks are fixed in the mounting groove and located outside the U-shaped connection area, with the two ends of the arc-shaped metal blocks abutting against the sidewalls of the two horizontal connection areas respectively; Two first metal coatings are respectively disposed on the upper surfaces of the two horizontal connection areas to connect the two ends of the two arc-shaped metal blocks, so that the two arc-shaped metal blocks and the two first metal coatings are connected to each other to form a closed shielding ring surrounding the resonant area. The top cover is fitted and sealed to the bottom base; A second metal coating is provided on the bottom surface of the top cover. After the top cover is fitted and sealed with the bottom base, the second metal coating abuts against the closed shielding ring. Also includes: Two signal pads are provided on the bottom surface of the sealing base; Two grounding pads are provided on the bottom surface of the sealed base; The first electrode layer is disposed on the top surface of the resonant region and the U-shaped connection region and the horizontal connection region on one side. The end of the first electrode layer is electrically connected to one of the signal pads through the resonant crystal chip and the metal via in the bottom base. The second electrode layer is disposed on the bottom surface of the resonant region and the other side U-shaped connection region and horizontal connection region. The end of the second electrode layer is electrically connected to another signal pad through a metal via in the sealing base. The two arc-shaped metal blocks are electrically connected to the two grounding pads through metal through holes in the bottom base, respectively; The ends of both the first electrode layer and the second electrode layer have isolation gaps from the closed shielding ring.

2. The crystal oscillator packaging structure according to claim 1, characterized in that, The bottom of the mounting groove has a damping groove, and an elastic pad is installed in the damping groove. The size and position of the elastic pad correspond to the size and position of the resonant area, and the height of the elastic pad is slightly higher than the damping groove.

3. The crystal oscillator packaging structure according to claim 1, characterized in that: The top edge of the sealing base is provided with a stepped sealing groove around the mounting groove. The stepped sealing groove is divided into an outer upper stepped groove and an inner lower stepped groove. A first sealing ring is provided in the upper stepped groove and a second sealing ring is provided in the lower stepped groove. The bottom surface of the top cover has an annular sealing boss corresponding to the stepped sealing groove.

4. The crystal oscillator packaging structure according to claim 1, characterized in that: The second metal coating is circular, with the same outer diameter as the arc-shaped metal block.

5. A crystal oscillator packaging structure according to claim 1, characterized in that: Conductive paste is applied to the contact surface between the closed shielding ring and the second metal coating.

6. The crystal oscillator packaging structure according to claim 1, characterized in that: The arc-shaped metal block is fixed in the mounting groove by conductive epoxy resin.

7. A crystal oscillator packaging structure according to claim 1, characterized in that: The frame area of ​​the resonant crystal chip is filled with damping gel between the frame area and the mounting groove.

8. The crystal oscillator packaging structure according to claim 1, characterized in that: One or more heat dissipation holes are provided on the bottom surface of the mounting slot.

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