Pressure welding block layout structure for resisting pressure welding bonding pressure

Abstract

The utility model provides a pressure welding block layout structure for resisting pressure welding bonding pressure, which comprises an active layer, a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, a top metal layer and an active region contact hole layer connected between the active layer and the first metal layer, the first through hole layer is connected between the first metal layer and the second metal layer, the second through hole layer is connected between the second metal layer and the third metal layer, the third through hole layer is connected between the third metal layer and the fourth metal layer, and the fourth through hole layer is connected between the fourth metal layer and the top metal layer. According to the utility model, a pyramid type metal structure is adopted, and pressure generated during pressure welding bonding is dispersed. A device arranged below the pressure welding block is protected, and punch-through is prevented; the pressure generated during pressure welding is resisted, so that a device can be placed below the pressure welding block, the area of a chip is saved, and the stability and the safety of the pressure welding block are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electrical components, in particular to a pressure welding block layout structure capable of resisting pressure of pressure welding bonding. Background Art

[0002] The bonding pad provides the connection interface between the chip and the external circuit. After the chip is manufactured, the bonding pad and the external interface are connected through bonding wires. These bonding wires are made of gold wire or silicon aluminum wire, and the bonding method is usually ball bonding. The ball bonding process uses a hydrogen flame to melt the end of the bonding wire into a metal ball, and then applies pressure to bond it to the top metal. The metal ball becomes a pancake shape due to pressure during the bonding process, and this pressure can cause stress-induced failure of the device.

[0003] Conventional pads use a top metal or two top metal layers, but this design can cause the following problems:

[0004] 1. A single or two-layer metal is not enough to withstand the pressure during bonding. Generally, according to design rules, no devices are allowed to be placed under the bonding block.

[0005] 2. Usually the area of ​​the bonding pad is very large, especially when there are many chip pins. When there are many bonding pads, the bonding pads under which the device cannot be placed will occupy a large area, resulting in reduced area efficiency.

[0006] 3. The bonding pad consisting of only one or two layers of metal relies solely on the adhesion between the metal and the semiconductor material. This structure can easily fail due to pulling and peeling.

[0007] Therefore, a bonding pad layout structure that can improve bonding efficiency is needed. Summary of the invention

[0008] The utility model aims to solve the problem of pressure welding efficiency, and provides a pressure welding block layout structure that resists pressure welding bonding, and adopts a pyramid-shaped metal structure to disperse the pressure generated during pressure welding bonding. The device placed under the pressure welding block is protected to prevent punch-through; the pressure generated during pressure welding is resisted, so that it is possible to place the device under the pressure welding block, which saves the area of ​​the chip and improves the stability and safety of the pressure welding block.

[0009] The utility model provides a welding block layout structure for resisting welding bonding pressure, comprising an active layer, a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, and a top metal layer arranged in sequence from bottom to top, an active area contact hole layer connected between the active layer and the first metal layer, a first through hole layer connected between the first metal layer and the second metal layer, a second through hole layer connected between the second metal layer and the third metal layer, a third through hole layer connected between the third metal layer and the fourth metal layer, and a fourth through hole layer connected between the fourth metal layer and the top metal layer;

[0010] The active layer, the first metal layer and the second metal layer are all hollow annular plate structures, the third metal layer, the fourth metal layer and the top metal layer are all square plate structures, and the total length and total width of the active layer, the first metal layer, the second metal layer, the third metal layer, the fourth metal layer and the top metal layer are the same;

[0011] The length and width of the hollow regions of the active layer and the first metal layer are the same, and the length and width of the hollow region of the second metal layer are smaller than those of the hollow regions of the active layer and the first metal layer;

[0012] The bond input points are connected on top of the top metal layer and the bottom of the active layer is connected to the substrate.

[0013] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding, as a preferred mode, the active layer, the first metal layer, the second metal layer, the third metal layer, the fourth metal layer, the top metal layer, the active area contact hole layer, the first through hole layer, the second through hole layer, the third through hole layer and the fourth through hole layer form a pyramid-shaped metal structure;

[0014] No through hole is provided in the corner area of ​​the active layer and the first metal layer;

[0015] The active layer is an n-type implanted epitaxial layer that is inversely related to the substrate.

[0016] The utility model discloses a layout structure of a pressure welding block for resisting pressure of pressure welding bonding. As a preferred mode, electronic devices can be placed in the hollow area between the first metal layer and the second metal layer below the third metal layer.

[0017] The utility model discloses a layout structure of a pressure welding block for resisting pressure of pressure welding. As a preferred mode, the first metal layer and the second metal layer are disconnected to set a wiring channel, and the electronic device is connected to the external area circuit through the wiring channel.

[0018] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding, and as a preferred embodiment, the active layer is an N-type epitaxial layer.

[0019] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding. As a preferred embodiment, the active layer, the first metal layer, the second metal layer, the third metal layer and the fourth metal layer can be formed by splicing multiple metals.

[0020] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding. As a preferred mode, the through holes of the active area contact hole layer, the first through hole layer, the second through hole layer, the third through hole layer and the fourth through hole layer are all filled with tungsten metal.

[0021] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding. As a preferred embodiment, the total length and total width of the third through hole layer are smaller than the internal length and width of the second through hole layer.

[0022] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding bonding. As a preferred embodiment, the total external length and total external width of the fourth through hole layer are smaller than the total internal length and total internal width of the third through hole layer.

[0023] The utility model discloses a pressure welding block layout structure for resisting pressure of pressure welding. As a preferred embodiment, the diameters of the through holes in the active area contact hole layer, the first through hole layer, the second through hole layer, the third through hole layer and the fourth through hole layer are all the same.

[0024] The utility model has the following advantages:

[0025] (1) The pyramid-shaped metal structure can disperse the pressure generated during bonding, so that it can resist the pressure generated during bonding and reduce the risk of stress failure of the device under the pad.

[0026] (2) The pyramid-shaped metal structure ensures that metal 1 and metal 2 under the window area can be arranged freely, making it possible to place devices under the bonding pad.

[0027] (3) The dense through holes between the multiple metal layers increase the bonding force between the metal layers, and the bonding pad is not easy to fail due to pulling and peeling during the bonding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of a layout structure of a pressure welding block that resists pressure of pressure welding bonding;

[0029] Figure 2 A partial enlarged diagram showing a layout structure of a pressure welding block that resists pressure of pressure welding bonding;

[0030] Figure 3 The schematic diagram is a cross-sectional view of a layout structure of a pressure welding block that resists pressure of pressure welding bonding.

[0031] Reference numerals:

[0032] 1. Active layer; 2. First metal layer; 3. Second metal layer; 4. Third metal layer; 5. Fourth metal layer; 6. Top metal layer; 7. Active area contact hole layer; 8. First through-hole layer; 9. Second through-hole layer; 10. Third through-hole layer; 11. Fourth through-hole layer. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0034] Example 1

[0035] like Figures 1 to 3 As shown, a layout structure of a pressure welding block resisting pressure of pressure welding bonding includes an active layer 1, a first metal layer 2, a second metal layer 3, a third metal layer 4, a fourth metal layer 5, and a top metal layer 6 arranged in sequence from bottom to top, an active area contact hole layer 7 connected between the active layer 1 and the first metal layer 2, a first through-hole layer 8 connected between the first metal layer 2 and the second metal layer 3, a second through-hole layer 9 connected between the second metal layer 3 and the third metal layer 4, a third through-hole layer 10 connected between the third metal layer 4 and the fourth metal layer 5, and a fourth through-hole layer 11 connected between the fourth metal layer 5 and the top metal layer 6;

[0036] The active layer 1, the first metal layer 2 and the second metal layer 3 are all hollow annular plate structures, the third metal layer 4, the fourth metal layer 5 and the top metal layer 6 are all square plate structures, and the total length and total width of the active layer 1, the first metal layer 2, the second metal layer 3, the third metal layer 4, the fourth metal layer 5 and the top metal layer 6 are the same;

[0037] The length and width of the hollow regions of the active layer 1 and the first metal layer 2 are the same, and the length and width of the hollow region of the second metal layer 3 are smaller than those of the active layer 1 and the first metal layer 2;

[0038] The pressure welding input point is connected to the top of the top metal layer 6, and the bottom of the active layer 1 is connected to the substrate;

[0039] The active layer 1, the first metal layer 2, the second metal layer 3, the third metal layer 4, the fourth metal layer 5, the top metal layer 6, the active area contact hole layer 7, the first through hole layer 8, the second through hole layer 9, the third through hole layer 10 and the fourth through hole layer 11 form a pyramid-shaped metal structure;

[0040] The active layer 1 is an N-type epitaxial layer;

[0041] No through hole is provided in the corner area between the active layer 1 and the first metal layer 2;

[0042] The active layer 1 is an n-type implanted epitaxial layer that is inverse to the substrate;

[0043] Below the third metal layer 4, electronic devices can be placed in the hollow area between the first metal layer 2 and the second metal layer 3;

[0044] The first metal layer 2 and the second metal layer 3 are disconnected to set a wiring channel, and the electronic device is connected to the external area circuit through the wiring channel;

[0045] The active layer 1, the first metal layer 2, the second metal layer 3, the third metal layer 4, and the fourth metal layer 5 can be formed by splicing multiple metals;

[0046] The through holes of the active area contact hole layer 7, the first through hole layer 8, the second through hole layer 9, the third through hole layer 10 and the fourth through hole layer 11 are all filled with tungsten metal;

[0047] The total length and width of the third through-hole layer 10 are smaller than the internal length and width of the second through-hole layer 9;

[0048] The external total length and the external total width of the fourth through-hole layer 11 are smaller than the internal total length and the internal total width of the third through-hole layer 10;

[0049] The diameters of the through holes in the active area contact hole layer 7 , the first through hole layer 8 , the second through hole layer 9 , the third through hole layer 10 and the fourth through hole layer 11 are all the same.

[0050] Figure 1 Taking 5 layers of metal as an example, the layout of the bonding pad of this embodiment is shown. Figure 2 The detailed metal layers and through-hole layers are shown. It can be seen that in addition to the top metal layer 6 and the fourth metal layer 5, this bonding pad also introduces the N-type epitaxial layer 1 and the first metal layer 2, the second metal layer 3, the third metal layer 4 and other layers, and connects these layers with through-holes.

[0051] The annular N-type epitaxial layer 1 and the first metal layer 2 form a physical connection between the entire structure and the substrate, but it is worth noting that the metal is connected to the potential input by the pad, so an n-type implanted epitaxial layer with a reverse type to the substrate is used. The annular first metal layer 2 and the second metal layer 3 reserve space for the wiring of the device below the window area.

[0052] Furthermore, since the through holes of the active area contact hole layer 7, the first through hole layer 8, the second through hole layer 9, the third through hole layer 10 and the fourth through hole layer 11 need to be filled with tungsten metal, which is relatively soft and not suitable for bearing the pressure during the pressure welding process, more through holes are used to disperse the pressure. If the warping deformation caused by internal stress is to be improved, the large area of ​​metal except the top metal 6 can be replaced with multiple small metal layers.

[0053] If the device under the pad has metal connections connected to the external area circuit, the first metal layer 2 and the second metal layer 3 at any position in the pad can be disconnected to reserve sufficient routing channels. In addition, the utility model deletes the through hole at the tip of the pad to reduce the avalanche breakdown induced by the enhanced electric field.

[0054] This metal structure forms a pyramidal structure. The purpose of adopting this structure is to disperse the downward pressure generated during bonding at a 45° angle downward on the vertical structure and in four directions perpendicular to the metal edge on the horizontal structure. This structure can effectively resist the pressure generated during pressure welding and avoid direct breakdown of the pressure welding block and the field oxide layer.

[0055] In this embodiment, the width of the active area 1 and the first metal layer 2 is 5um, the width of the second metal layer 3 is 10um, the third metal layer 4, the fourth metal layer 5 and the top metal 6 are all 75um×75um squares, the diameters of the through holes of the active area contact hole layer 7, the first through hole layer 8, the second through hole layer 9, the third through hole layer 10 and the fourth through hole layer 11 are all 0.26μm, and the spacing between the through holes is also 0.26μm. The total length and total width of the fourth through hole layer 11 are both 45μm, and the total length and total width of the third through hole layer 10 are both 53μm.

[0056] Figure 3 The cross-section of the pad and the effect of pressure dispersion are shown. The overlapping layers of metal form a pyramid-shaped structure. The downward pressure generated during bonding is dispersed, allowing the pad to effectively resist the pressure generated during bonding and avoid direct breakdown of the pad and the circuit below.

[0057] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A pad layout structure for resisting pressure of pressure welding, characterized in that: The invention comprises an active layer (1), a first metal layer (2), a second metal layer (3), a third metal layer (4), a fourth metal layer (5), and a top metal layer (6) which are arranged in sequence from bottom to top; an active region contact hole layer (7) connected between the active layer (1) and the first metal layer (2); a first through hole layer (8) connected between the first metal layer (2) and the second metal layer (3); a second through hole layer (9) connected between the second metal layer (3) and the third metal layer (4); a third through hole layer (10) connected between the third metal layer (4) and the fourth metal layer (5); and a fourth through hole layer (11) connected between the fourth metal layer (5) and the top metal layer (6); The active layer (1), the first metal layer (2) and the second metal layer (3) are all hollow annular plate structures, the third metal layer (4), the fourth metal layer (5) and the top metal layer (6) are all square plate structures, and the total length and total width of the active layer (1), the first metal layer (2), the second metal layer (3), the third metal layer (4), the fourth metal layer (5) and the top metal layer (6) are all the same; The length and width of the hollow regions of the active layer (1) and the first metal layer (2) are the same, and the length and width of the hollow region of the second metal layer (3) are smaller than the length and width of the hollow regions of the active layer (1) and the first metal layer (2); The bonding input point is connected to the top of the top metal layer (6), and the bottom of the active layer (1) is connected to the substrate.

2. A bonding pad layout structure for resisting bonding pressure according to claim 1, characterized in that: The active layer (1), the first metal layer (2), the second metal layer (3), the third metal layer (4), the fourth metal layer (5), the top metal layer (6), the active area contact hole layer (7), the first through hole layer (8), the second through hole layer (9), the third through hole layer (10) and the fourth through hole layer (11) form a pyramid-shaped metal structure; No through holes are provided in the corner regions of the active layer (1) and the first metal layer (2); The active layer (1) is an n-type implanted epitaxial layer that is inversely related to the substrate.

3. A pad layout structure for resisting pressure during bonding according to claim 1, characterized in that: Electronic devices can be placed in the hollow areas of the first metal layer (2) and the second metal layer (3) below the third metal layer (4).

4. A bonding pad layout structure for resisting bonding pressure according to claim 3, characterized in that: The first metal layer (2) and the second metal layer (3) are disconnected to set up a wiring channel, and the electronic device is connected to an external regional circuit through the wiring channel.

5. The pad layout structure for resisting pressure of pressure welding according to claim 1, characterized in that: The active layer (1) is an N-type epitaxial layer.

6. The pad layout structure for resisting pressure of pressure welding according to claim 1, characterized in that: The active layer (1), the first metal layer (2), the second metal layer (3), the third metal layer (4), and the fourth metal layer (5) can be formed by splicing a plurality of metals.

7. The pad layout structure for resisting pressure of pressure welding according to claim 1, characterized in that: The through holes of the active area contact hole layer (7), the first through hole layer (8), the second through hole layer (9), the third through hole layer (10) and the fourth through hole layer (11) are all filled with tungsten metal.

8. The pad layout structure for resisting pressure of pressure welding according to claim 1, characterized in that: The total length and total width of the third through-hole layer (10) are smaller than the internal length and width of the second through-hole layer (9).

9. A bonding pad layout structure for resisting bonding pressure according to claim 8, characterized in that: The external total length and the external total width of the fourth through-hole layer (11) are smaller than the internal total length and the internal total width of the third through-hole layer (10).

10. The pad layout structure for resisting pressure of pressure welding according to claim 1, characterized in that: The through hole diameters of the active area contact hole layer (7), the first through hole layer (8), the second through hole layer (9), the third through hole layer (10) and the fourth through hole layer (11) are all the same.

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