Lead-out structure of ceramic embedded metal layer

Abstract

The invention discloses a ceramic embedded metal layer lead-out structure, which comprises a ceramic main body, a ceramic thin layer is fixed on the surface of the ceramic main body, and an electrode layer is arranged between the ceramic thin layer and the ceramic main body; the electrode stem is arranged in the cavity of the ceramic main body, a transition metal block is arranged above the electrode stem, and a leading-out joint I is arranged above the transition metal block; the second leading-out connector is connected with the first leading-out connector and the electrode layer, and the second leading-out connector is located over the electrode rod and the first leading-out connector. A traditional single leading-out connector is divided into the first leading-out connector and the second leading-out connector, the thickness of a ceramic layer above the first connector is increased through non-right-upper staggered layout, and the crack risk caused by insufficient thickness is reduced. The transition metal block is additionally arranged between the electrode rod and the first leading-out connector, the thermal expansion coefficient of the transition metal block is similar to that of the ceramic body, thermal stress can be buffered when the temperature changes, and the stability and reliability of the ceramic semiconductor device can be effectively improved.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of semiconductor manufacturing processes, and particularly relates to a ceramic embedded metal layer lead-out structure. Background Art

[0002] In semiconductor manufacturing, a metal mesh is often embedded within the metal lead structure embedded within a ceramic or within a ceramic electrostatic chuck. This mesh can serve as an RF electrode, plasma ground electrode, or adsorption electrode. Due to application limitations, this metal electrode layer is only 1-2 mm from the ceramic surface, making it difficult to increase its thickness.

[0003] When the device is subjected to temperature or current shocks, stress concentration is easily generated at the electrode lead joint due to differences in the thermal expansion characteristics of the materials. This can cause cracking in the thin ceramic layer above the joint, ultimately leading to product failure. Specifically, due to the difference in thermal expansion coefficients between ceramic and metallic nickel, the metallic nickel expands during heating, causing the tungsten-molybdenum joint and the tungsten-molybdenum electrode mesh to be subjected to stress generated by the nickel expansion. The surface ceramic is then subjected to the compressive stress of the electrode mesh, causing microcracks to form at the interface between the ceramic and the tungsten-molybdenum electrode mesh. As stress continues to accumulate, the cracks gradually extend upward, ultimately leading to product failure. Summary of the Invention

[0004] The purpose of the present invention is to provide a ceramic embedded metal layer lead-out structure to solve the problems in the prior art.

[0005] At least one embodiment of the present disclosure provides a ceramic-embedded metal layer lead-out structure, comprising:

[0006] a ceramic body, wherein a ceramic thin layer is fixed on the surface of the ceramic body, and an electrode layer is provided between the ceramic thin layer and the ceramic body;

[0007] An electrode rod, the electrode rod being disposed in the cavity of the ceramic body, a transition metal block being disposed above the electrode rod, and a first lead-out connector being disposed above the transition metal block;

[0008] Lead-out connector 2, the lead-out connector 2 connects the lead-out connector 1 and the electrode layer, and the lead-out connector 2 is not directly above the electrode rod and the lead-out connector 1.

[0009] For example, in the ceramic-embedded metal layer lead-out structure provided in an embodiment of the present disclosure, the inner wall of the cavity is connected to a fixed joint via threads, and the transition metal block is also fixed inside the fixed joint.

[0010] For example, in the ceramic-embedded metal layer lead-out structure provided in one embodiment of the present disclosure, the thermal expansion coefficient of the transition metal block is close to the thermal expansion coefficient of the ceramic body.

[0011] For example, in the ceramic embedded metal layer lead-out structure provided in one embodiment of the present disclosure, the transition metal block is a kovar metal block, the kovar metal block is welded to the electrode rod through solder, and the kovar metal block is welded to the bottom of the lead-out joint one.

[0012] For example, in the ceramic embedded metal layer lead-out structure provided in an embodiment of the present disclosure, the joint 2 is arranged on the left or right side of the lead-out joint 1, and the distance between the longitudinal center axis of the lead-out joint 1 and the longitudinal center axis of the lead-out joint 2 is not less than the sum of the radii of the lead-out joint 1 and the lead-out joint 2.

[0013] For example, in the ceramic embedded metal layer lead-out structure provided in an embodiment of the present disclosure, there is a distance between the upper surface of the lead-out connector 1 and the upper surface of the ceramic body.

[0014] For example, in the ceramic embedded metal layer lead-out structure provided in one embodiment of the present disclosure, the inner wall of the cavity is provided with partial threads in the longitudinal direction, and the upper end faces of the transition metal block and the electrode rod are flush with the upper end faces of the threads.

[0015] For example, in the ceramic embedded metal layer lead-out structure provided in an embodiment of the present disclosure, the first connector and the second connector are connected via a connecting component, the connecting component is a thin structure, and the connecting component is located inside the ceramic body.

[0016] For example, in the ceramic-embedded metal layer lead-out structure provided in one embodiment of the present disclosure, the connecting component is a connecting wire or a connecting mesh.

[0017] For example, in the ceramic embedded metal layer lead-out structure provided in one embodiment of the present disclosure, the electrode layer, the lead-out connector 1, the lead-out connector 2 and the connecting component are made of tungsten or molybdenum, and the electrode rod and the fixed connector are made of nickel.

[0018] Beneficial effects:

[0019] 1. The present invention provides a ceramic-embedded metal layer lead-out structure, which splits the traditional single lead-out connector into lead-out connector 1 and lead-out connector 2. The thickness of the ceramic layer above connector 1 is increased through a non-directly offset layout, significantly improving the mechanical strength of the ceramic layer and reducing the risk of cracks caused by insufficient thickness. Secondly, a transition metal block (such as Kovar alloy) is added between the electrode rod and lead-out connector 1. Its thermal expansion coefficient is similar to that of the ceramic body, which can buffer thermal stress during temperature changes and avoid extrusion damage to the ceramic layer due to differences in metal expansion. This can effectively improve the stability and reliability of the ceramic semiconductor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a schematic structural diagram of the ceramic embedded metal layer lead-out structure provided by the present invention.

[0022] In the figure: 1. Ceramic body; 2. Ceramic thin layer; 3. Electrode layer; 4. Electrode rod; 5. Cavity; 6. Transition metal block; 7. Lead-out connector 1; 8. Lead-out connector 2; 9. Fixed connector; 10. Connecting component; 11. Solder. DETAILED DESCRIPTION

[0023] The present invention may be more readily understood by referring to the following detailed description of preferred embodiments of the present invention and the included Examples. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention pertains. In the event of a conflict, the definitions in this specification shall prevail.

[0024] The present disclosure provides a ceramic embedded metal layer lead-out structure, which solves the problem in the prior art that due to the difference in thermal expansion coefficients between ceramic and metallic nickel, the metallic nickel expands during heating, causing the tungsten-molybdenum joint and the tungsten-molybdenum electrode mesh to be subjected to the stress generated by the nickel expansion, and the surface ceramic to be subjected to the extrusion stress of the electrode mesh, resulting in fine cracks at the interface between the ceramic and the tungsten-molybdenum electrode mesh, which in turn leads to product failure.

[0025] The technical concept provided by the present disclosure is that, on the one hand, by splitting an integral lead-out joint into two separate lead-out joints and adjusting the relative positions of the two lead-out joints so that the two lead-out joints are not on the same longitudinal axis, the thickness of the ceramic above the connector above the electrode rod is increased to reduce the problem of easy breakage due to the thin thickness of the ceramic plate; on the other hand, by arranging a buffer metal block with a thermal expansion coefficient similar to that of the ceramic between the electrode rod and the connector, the stress generated by the thermal expansion difference between the rod and the lead-out joint can be effectively buffered when the temperature changes, thereby reducing the problem of ceramic cracking caused by stress accumulation.

[0026] like Figure 1 As shown, a ceramic embedded metal layer lead-out structure includes:

[0027] Ceramic body 1, which is the main structure of a ceramic heater or a ceramic electrostatic chuck, has a ceramic thin layer 2 fixed on the surface of the ceramic body 1. In some embodiments, the ceramic thin layer 2 is arranged above the ceramic body 1, and an electrode layer 3 is arranged between the ceramic thin layer 2 and the ceramic body 1. During use, current will pass through the electrode layer 3 and the temperature of the electrode layer 3 will rise. The joints of the electrode layer 3 are prone to stress concentration due to different material thermal expansion coefficients, which may cause cracking or even failure of the ceramic thin layer 2. However, since the electrode layer 3 is used as a radio frequency electrode, plasma grounding or adsorption electrode, if the ceramic thin layer 2 is too thick, it may easily lead to functional failure of the electrode layer 3.

[0028] A cavity 5 is provided at the bottom of the ceramic body 1. An electrode rod 4 is fixed within the cavity 5. A transition metal block 6 is provided above the electrode rod 4. A first lead connector 7 is provided above the transition metal block 6. A second lead connector 8 is provided on the upper half of the ceramic body 1. The second lead connector 8 is electrically connected to the electrode layer 3 and is also electrically connected to the first lead connector 7.

[0029] Lead-out connector 2 8 is arranged not directly above lead-out connector 1 7. In some embodiments, lead-out connector 2 8 is moved to the side of lead-out connector 1 7. Through the staggered design of lead-out connector 1 7 and lead-out connector 2, the thickness of the ceramic above lead-out connector 1 7 is increased. As the ceramic thickness increases, the strength of the ceramic layer above lead-out connector 1 7 is increased, thereby preventing the upper ceramic layer from cracking.

[0030] Above the electrode rod 4, a transition metal block 6 with a similar thermal expansion coefficient to the ceramic body 1 is positioned. This effectively buffers the stress concentration caused by the difference in thermal expansion coefficients between the electrode rod 4 and the lead connector 7 during temperature fluctuations, thereby reducing problems such as ceramic cracking and component deformation caused by stress accumulation. By optimizing the lead connector's spatial dimensions and comprehensively optimizing the transition metal block 6, the stability and reliability of the ceramic semiconductor layer are effectively improved, effectively resolving the problems existing in the prior art.

[0031] In one embodiment, a fixing joint 9 is connected to the inner wall of the cavity 5 through a thread, and the transition metal block 6 is also fixed inside the fixing joint 9. The fixing joint 9 is a cylindrical hollow structure, and a circular protrusion is formed on the outside of the fixing joint 9, and a thread that matches the thread of the inner wall of the cavity 5 is provided on the outside of the circular protrusion. The fixing joint 9 can be screwed into the interior of the ceramic body 1 through the inner cavity, so that the fixing joint 9 can be fixed to the ceramic body 1. In summary, the provision of the cavity 5 in the ceramic body 1 can, on the one hand, fix the joint 9, and thus fix the electrode rod 4 and the metal buffer block, and on the other hand, the fixing joint 9 is in contact with the inner wall of the cavity 5 only through the circular protrusion, and the other gaps in the cavity 5 leave a buffer space for the thermal expansion of the ceramic body 1 and the fixing joint 9, so as to reduce the damage to the ceramic body 1 caused by expansion and extrusion.

[0032] In one embodiment, the inner wall of the cavity 5 is partially threaded in the longitudinal direction. The upper end faces of the transition metal block 6 and the electrode rod 4 are aligned as flush as possible with the upper end faces of the threads, with an error range of 1-3 mm. This minimizes the stress on the lead-out connector 7 and reduces ceramic cracking caused by stress accumulation. It is understood that in mechanical structures, stress concentration often arises from sudden changes in geometric shape (such as steps and notches). When the distance between the weld surface of the buffer metal block and the electrode rod 4 and the upper end face of the threads is controlled within 1-3 mm, the structural transition is smoother, the sudden change in geometric shape is reduced, and the stress concentration phenomenon is alleviated. If the gap between the weld surface and the upper end face of the threads is too large, a significant step will form, and external force transmission will easily cause stress concentration near the lead-out connector 7, resulting in increased stress. When the gap is controlled within 1-3 mm, the structural continuity is enhanced, the stress distribution is more uniform, and the additional stress on the lead-out connector 7 is reduced.

[0033] In one embodiment, the thermal expansion coefficient of the transition metal block 6 is similar to that of the ceramic body 1. Specifically, the transition metal block 6 is a Kovar metal block, i.e., a Kovar alloy. The Kovar metal block is soldered to the electrode rod 4 via solder 11, and the Kovar metal block is soldered to the bottom of the lead connector 7. Kovar alloy (also known as Kovar alloy or 4J29 alloy) is a typical Fe-Ni-Co hard glass sealing alloy. Its main components are iron (balance), nickel (28.5% to 29.5%), cobalt (16.8% to 17.8%), and contains small amounts of manganese, silicon, phosphorus, sulfur, and other elements. Kovar alloy has a thermal expansion coefficient similar to that of borosilicate hard glass in the temperature range of 20°C to 450°C, a high Curie point, and good low-temperature structural stability.

[0034] In one embodiment, lead connector 2 8 is positioned to the left or right of lead connector 1 7, and the distance between the longitudinal center axis of lead connector 1 7 and the longitudinal center axis of lead connector 2 8 is no less than the sum of the radii of lead connector 1 7 and lead connector 2 8. Specifically, the distance between the circumferential surface of lead connector 2 8 and the circumferential surface of lead connector 1 7 increases the thickness of the ceramic above lead connector 1 7, thereby reducing the risk of ceramic cracks even if there is a distance between the upper surface of lead connector 1 7 and the upper surface of ceramic body 1.

[0035] In one embodiment, the lead-out connector 1 7 and the lead-out connector 2 8 are electrically connected via a connecting component 10. The connecting component 10 is a thin structure and is located inside the ceramic body 1, wherein the connecting component 10 is a connecting wire or a connecting mesh. The forming of the connecting component 10 can be made by co-firing or screen printing. The preparation steps of the co-firing method include preparing a ceramic green body (unsintered ceramic body) and placing the connecting component 10 in the green body according to the designed position. The ceramic green body and the connecting component 10 are co-sintered. At high temperature, the ceramic green body is densified to form the ceramic body 1, and the connecting component 10 is fixedly embedded therein. The preparation steps of the screen printing method include making a metal connecting material (such as silver, gold, etc.) into a slurry, and printing the slurry onto the surface of the ceramic green body or a predetermined position inside the ceramic green body according to the designed pattern through a screen printing process. The ceramic green body is sintered, the organic components in the slurry are volatilized, the metal components are densified, and the connecting component 10 is formed and combined with the ceramic body 1.

[0036] In one embodiment, the electrode layer 3, the lead connector 1 7, the lead connector 2 8 and the connecting component 10 are made of tungsten or molybdenum, and the electrode rod 4 and the fixed connector 9 are made of nickel to ensure electrical conductivity.

[0037] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A ceramic embedded metal layer lead-out structure, characterized in that: include: a ceramic body, wherein a ceramic thin layer is fixed on the surface of the ceramic body, and an electrode layer is provided between the ceramic thin layer and the ceramic body; An electrode rod, the electrode rod being disposed in the cavity of the ceramic body, a transition metal block being disposed above the electrode rod, and a first lead-out connector being disposed above the transition metal block; Lead-out connector 2, the lead-out connector 2 connects the lead-out connector 1 and the electrode layer, and the lead-out connector 2 is not directly above the electrode rod and the lead-out connector 1.

2. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: The inner wall of the cavity is connected with a fixed joint via threads, and the transition metal block is also fixed inside the fixed joint.

3. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: The thermal expansion coefficient of the transition metal block is similar to the thermal expansion coefficient of the ceramic body.

4. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: The transition metal block is a kovar metal block, the kovar metal block is welded to the electrode rod via solder, and the kovar metal block is welded to the bottom of the first lead-out connector.

5. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: The lead-out joint 2 is arranged on the left side or right side of the lead-out joint 1, and the distance between the longitudinal center axis of the lead-out joint 1 and the longitudinal center axis of the lead-out joint 2 is not less than the sum of the radii of the lead-out joint 1 and the lead-out joint 2.

6. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: There is a distance between the upper surface of the first lead-out connector and the upper surface of the ceramic body.

7. The ceramic embedded metal layer lead-out structure according to claim 1, characterized in that: The inner wall of the cavity is provided with a partial thread in the longitudinal direction, and the upper end surfaces of the transition metal block and the electrode rod are flush with the upper end surfaces of the thread.

8. The ceramic embedded metal layer lead-out structure according to claim 2, characterized in that: The first lead-out connector and the second lead-out connector are connected via a connecting component. The connecting component is a thin structure and is located inside the ceramic body.

9. The ceramic embedded metal layer lead-out structure according to claim 8, characterized in that: The connecting component is a connecting wire or a connecting net.

10. The ceramic embedded metal layer lead-out structure according to claim 8, characterized in that: The electrode layer, the first lead-out connector, the second lead-out connector, and the connecting component are made of tungsten or molybdenum, and the electrode rod and the fixed connector are made of nickel.

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