Ceramic smd base

Abstract

The utility model belongs to the surface mounting welding ceramic packaging base technical field discloses a kind of ceramic SMD pedestal, the ceramic SMD pedestal includes top seat and pedestal fixed together, and the top surface of top seat is equipped with Kovar ring around, and first foot stand and second foot stand are equipped in the top recess surrounded by Kovar ring;The top surface of Kovar ring, first foot stand and second foot stand is sequentially equipped with ceramic base and nickel layer from inside to outside;The bottom surface of pedestal is equipped with third foot stand, fourth foot stand, fifth foot stand and sixth foot stand, and the bottom surface of third foot stand, fourth foot stand, fifth foot stand and sixth foot stand is sequentially equipped with ceramic base, nickel layer and tin layer from inside to outside.The beneficial effects of the utility model are: by using nickel layer and nickel layer and tin layer replace traditional nickel layer+gold layer, reduce the use of noble metal gold, reduce material cost.

Description

Technical Field

[0001] This utility model belongs to the technical field of surface mount ceramic packaging base, and particularly relates to a ceramic SMD base. Background Technology

[0002] Ceramic SMD substrates are widely used in high-frequency electronic components, such as quartz crystal resonators, surface acoustic wave filters, and RF modules, which require high reliability, good hermeticity, and stable electrical performance.

[0003] Traditional bases use a gold (Au) layer as an electrode or welding layer, but gold is expensive and may cause metal migration problems in some applications, such as high temperature or high humidity environments, affecting long-term stability. Furthermore, due to the high cost of the gold layer, the thickness of the gold layer is made small enough to ensure feasible performance, resulting in an excessively thin gold layer that is prone to wear and peeling during reprocessing. Summary of the Invention

[0004] The purpose of this utility model embodiment is to provide a ceramic SMD base, which aims to solve the problem that traditional bases use a gold (Au) layer as an electrode or welding layer, but gold is expensive and may have metal migration problems in some applications such as high temperature or high humidity environments, affecting long-term stability. In addition, due to the high cost of the gold layer, the thickness of the gold layer is made small enough to ensure feasible performance, resulting in an excessively thin gold layer that is prone to wear and peeling during production.

[0005] The present invention is implemented as follows:

[0006] A ceramic SMD base includes a top seat and a base fixed together. The top surface of the top seat is provided with a Kovar ring around its perimeter, and a first foot and a second foot are provided in the top groove formed by the Kovar ring. The top surfaces of the Kovar ring, the first foot, and the second foot are provided with a ceramic substrate and a nickel layer from the inside out. The bottom surface of the base is provided with a third foot, a fourth foot, a fifth foot, and a sixth foot. The bottom surfaces of the third foot, the fourth foot, the fifth foot, and the sixth foot are provided with a ceramic substrate, a nickel layer, and a tin layer from the inside out.

[0007] Furthermore, the nickel layer comprises, from the inside out, an electroplated nickel layer and a chemically plated nickel layer.

[0008] Furthermore, a tungsten layer is provided between the ceramic substrate and the nickel layer.

[0009] Furthermore, the first and second feet are located at two adjacent apex corners of the top groove, and the third, fourth, fifth, and sixth feet are located at the four apex corners of the bottom surface of the base.

[0010] Furthermore, the thickness A of the nickel layer is ≥ 3 μm.

[0011] Furthermore, the thickness B of the electroplated nickel layer is ≥2μm, and the thickness C of the chemically plated nickel layer is ≥1μm.

[0012] Furthermore, the thickness D of the tin layer is ≥ 3 μm.

[0013] Furthermore, the thickness of the tin layer is 3μm≤D≤10μm.

[0014] The positive effects of this utility model are:

[0015] By using a nickel layer or a nickel and tin layer instead of the traditional nickel + gold layer, the use of precious metal gold is reduced, thus lowering material costs. At the same time, tin (Sn) has better compatibility with lead-free solder than gold, which can improve soldering strength and reliability, and reduce the risk of poor soldering or brittle fracture. In addition, the nickel layer acts as a barrier layer to prevent diffusion between tin and the ceramic substrate, ensuring interface stability. The nickel layer provides good corrosion resistance and mechanical strength, while the tin layer has better oxidation resistance than gold in high temperature and high humidity environments, making it suitable for harsh working conditions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a three-dimensional structure of a ceramic SMD base according to the present invention;

[0017] Figure 2 yes Figure 1 The image shown is an enlarged view of point E of a ceramic SMD base according to this utility model.

[0018] Figure 3 yes Figure 1 The diagram shows a three-dimensional structural schematic of a ceramic SMD base according to the present invention from a second perspective.

[0019] Figure 4 yes Figure 1 The figure shown is a front view of a ceramic SMD base according to this utility model;

[0020] Figure 5 yes Figure 4 The figure shown is a top view of a ceramic SMD base according to this utility model;

[0021] Figure 6 yes Figure 4 The figure shown is a bottom view of a ceramic SMD base according to this utility model;

[0022] Legend: 1—Top seat, 2—Top groove, 3—Kovar ring, 4—First foot, 5—Second foot, 6—Mating surface, 7—Base, 8—Bottom surface, 9—Third foot, 10—Fourth foot, 11—Fifth foot, 12—Sixth foot, 13—First nickel layer, 1301—First electroplated nickel layer, 1302—First electroplated nickel layer, 14—Second nickel layer, 1401—Second electroplated nickel layer, 1402—Second electroplated nickel layer. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments:

[0024] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0025] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0026] SMD is an abbreviation for Surface Mount Device, which refers to electronic components that can be directly soldered using surface mount technology.

[0027] like Figures 1 to 6 The diagram shown is a structural diagram of a ceramic SMD base provided in an embodiment of this utility model, comprising:

[0028] A ceramic SMD base includes a top seat and a base fixed together. The top surface of the top seat is provided with a Kovar ring around its perimeter, and a first foot and a second foot are provided in the top groove formed by the Kovar ring. The top surfaces of the Kovar ring, the first foot, and the second foot are provided with a ceramic substrate and a nickel layer from the inside out. The bottom surface of the base is provided with a third foot, a fourth foot, a fifth foot, and a sixth foot. The bottom surfaces of the third foot, the fourth foot, the fifth foot, and the sixth foot are provided with a ceramic substrate, a nickel layer, and a tin layer from the inside out.

[0029] In this embodiment, by using a nickel layer and a nickel and tin layer instead of the traditional nickel + gold layer, the use of precious metal gold is reduced, thus lowering material costs. At the same time, tin (Sn) has better compatibility with lead-free solder than gold, which can improve soldering strength and reliability, and reduce the risk of poor soldering or brittle fracture. In addition, the nickel layer acts as a barrier layer to prevent diffusion between tin and the ceramic substrate, ensuring interface stability. The nickel layer provides good corrosion resistance and mechanical strength, and the tin layer has better oxidation resistance than gold in high temperature and high humidity environments, making it suitable for harsh working conditions.

[0030] Specifically, a ceramic SMD base includes a top seat 1 and a base 7 fixed together, which are fixed together by press fitting or welding.

[0031] The top surface of the top seat 1 is provided with Kovar rings 3 around its top surface. The top groove 2 formed by the Kovar rings 3 is provided with a first foot seat 4 and a second foot seat 5. The top surfaces of the Kovar rings 3, the first foot seat 4 and the second foot seat 5 are provided with a ceramic substrate and a first nickel layer 13 from the inside to the outside. The bottom surface of the base 7 is provided with a third foot seat 9, a fourth foot seat 10, a fifth foot seat 11 and a sixth foot seat 12. The bottom surfaces of the third foot seat 9, the fourth foot seat 10, the fifth foot seat 11 and the sixth foot seat 12 are provided with a ceramic substrate, a second nickel layer 14 and a tin layer from the inside to the outside.

[0032] Furthermore, the nickel layer comprises, from the inside out, an electroplated nickel layer and a chemically plated nickel layer; specifically, the first nickel layer 13 comprises, from the inside out, a first electroplated nickel layer 1302 and a first chemically plated nickel layer 1301; the second nickel layer 14 comprises, from the inside out, a second electroplated nickel layer 1401 and a second chemically plated nickel layer 1402.

[0033] Furthermore, a tungsten layer is provided between the ceramic substrate and the nickel layer. Specifically, a tungsten layer is provided on the side of the first electroplated nickel layer 1302 of the top seat 1 away from the first electroplated nickel layer 1301; a tungsten layer is provided on the side of the second electroplated nickel layer 1401 of the base 7 away from the second electroplated nickel layer 1402; the tungsten layer is formed by coating with tungsten paste, which includes tungsten and ceramic powder mixed together.

[0034] Furthermore, the first and second feet are located at two adjacent apex corners of the top groove, and the third, fourth, fifth, and sixth feet are located at the four apex corners of the bottom surface of the base.

[0035] Furthermore, the thickness A of the nickel layer is ≥ 3 μm.

[0036] Furthermore, the thickness B of the electroplated nickel layer is ≥2μm, and the thickness C of the chemically plated nickel layer is ≥1μm.

[0037] Furthermore, the thickness D of the tin layer is ≥ 3 μm.

[0038] Furthermore, the thickness of the tin layer is 3μm≤D≤10μm.

[0039] Traditionally, the thickness of the gold layer is 0.05μm to 0.1μm, while in the structure provided by this utility model, the thickness of the tin layer is D≥3μm, preferably 3μm≤D≤10μm, which is at least 30 times the thickness of the gold layer. This ensures that the tin layer has sufficient wear resistance and stability during the production of ceramic SMD substrates, resulting in a stronger weld.

[0040] When it is actually manufactured...

[0041] The first step is to fix the top seat 1 and the base 7 together by press-fitting or welding. The first foot seat 4 and the second foot seat 5 are connected to the third foot seat 9, the fourth foot seat 10, the fifth foot seat 11 and the sixth foot seat 12 in a specified manner.

[0042] The second step involves electroplating nickel on the top surface of the top seat 1 and the bottom surface of the base 7, as well as on the first foot seat 4, the second foot seat 5, the third foot seat 9, the fourth foot seat 10, the fifth foot seat 11, and the sixth foot seat 12, followed by chemical plating.

[0043] The third step is to plate tin on the outside of the nickel plating layer of the third pin 9, the fourth pin 10, the fifth pin 11, and the sixth pin 12.

[0044] The foregoing has broadly outlined some aspects and features of the various embodiments and should be interpreted as merely illustrative of potential applications. Other beneficial results can be obtained by applying the disclosed information in different ways or by combining aspects of the disclosed embodiments. Further aspects and a more complete understanding can be obtained based on the detailed description of exemplary embodiments with reference to the accompanying drawings, within the scope defined by the claims.

[0045] The above embodiments provide a detailed description of the present invention. Of course, the above description is not intended to limit the present invention, nor is the present invention limited to the examples described above. Any changes, modifications, additions, reductions, or substitutions made by those skilled in the art within the scope of the present invention are also within the protection scope of the present invention.

Claims

1. A ceramic SMD base, characterized in that, The ceramic SMD base includes a top seat and a base fixed together. The top surface of the top seat is provided with a Kovar ring around its perimeter. The top groove formed by the Kovar ring is provided with a first foot and a second foot. The top surfaces of the Kovar ring, the first foot, and the second foot are provided with a ceramic substrate and a nickel layer from the inside out. The bottom surface of the base is provided with a third foot, a fourth foot, a fifth foot, and a sixth foot. The bottom surfaces of the third foot, the fourth foot, the fifth foot, and the sixth foot are provided with a ceramic substrate, a nickel layer, and a tin layer from the inside out.

2. The ceramic SMD base according to claim 1, characterized in that, The nickel layer consists of an electroplated nickel layer and a chemically plated nickel layer from the inside out.

3. The ceramic SMD base according to claim 2, characterized in that, A tungsten layer is also provided between the ceramic substrate and the nickel layer.

4. The ceramic SMD base according to claim 3, characterized in that, The first and second feet are located at the two adjacent apex corners of the top groove, and the third, fourth, fifth and sixth feet are located at the four apex corners of the bottom surface of the base.

5. A ceramic SMD base according to any one of claims 1 to 4, characterized in that, The thickness A of the nickel layer is ≥ 3 μm.

6. The ceramic SMD base according to claim 5, characterized in that, The thickness of electroplated nickel in the nickel layer is B≥2μm, and the thickness of electroless nickel plating is C≥1μm.

7. A ceramic SMD base according to claim 5, characterized in that, The thickness D of the tin layer is ≥3μm.

8. The ceramic SMD base according to claim 5, characterized in that, The thickness of the tin layer is 3μm≤D≤10μm.

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