TGV adapter plate, manufacturing method and chip

Abstract

The invention provides a TGV adapter plate, a manufacturing method and a chip, the TGV adapter plate comprises a glass substrate, and the glass substrate is provided with a plurality of through holes; the through hole penetrates in the thickness direction of the glass substrate, and the diameter of the upper end of the through hole is larger than that of the lower end of the through hole; the elastic layer is arranged on the inner wall of the through hole; the through hole is filled with the conductive layer, and the elastic layer is located between the conductive layer and the inner wall of the through hole. According to the TGV adapter plate, the conductive layer is prevented from being directly combined with the glass substrate through the elastic layer, stress is buffered through the elastic layer, the situation that the glass substrate is broken due to the fact that local stress of the through holes is too large can be avoided, the strength of the TGV adapter plate is enhanced, deformation of the adapter plate is avoided, the strength and durability of the TGV adapter plate are improved, and the service life of the adapter plate is prolonged.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of chip technology, and in particular to a TGV adapter board, a manufacturing method and a chip. Background Art

[0002] The interposer in 3D packaging technology, also known as an insertion layer or middle layer, is a new type of electronic substrate. Many through-glass vias (TGV) are set on the interposer. The through-glass vias (TGV) extend through the substrate to interconnect, realizing vertical integration while shortening the interconnection length.

[0003] Currently, the conductive layer of TGV (through glass via) is mainly filled by metallization. However, since the conductive layer is in direct contact with the glass substrate, the stress formed in the through hole can easily cause the glass substrate to crack, thus affecting the service life of the TGV adapter board. Summary of the invention

[0004] The embodiments of the present invention provide a TGV adapter plate, a manufacturing method and a chip to solve the problem that the conductive layer of the existing TGV adapter plate directly contacts the glass substrate, causing the glass substrate to be easily broken.

[0005] In order to solve the above-mentioned technical problems, the present invention is achieved as follows:

[0006] In a first aspect, an embodiment of the present invention provides a TGV adapter board, characterized in that it includes:

[0007] A glass substrate, wherein a plurality of through holes are provided on the glass substrate; the through holes penetrate along the thickness direction of the glass substrate, and the upper end diameter of the through holes is larger than the lower end diameter;

[0008] An elastic layer, disposed on the inner wall of the through hole;

[0009] The conductive layer is filled in the through hole, and the elastic layer is located between the conductive layer and the inner wall of the through hole.

[0010] Optionally, each of the through holes comprises:

[0011] A first through hole and a second through hole, wherein the first through hole is located at an upper end of the second through hole and is communicated with the second through hole;

[0012] The first through hole is in a truncated cone shape, the bottom diameter of the truncated cone is smaller than the top diameter, and is the same as the top diameter of the second through hole;

[0013] The second through hole is columnar, and an axis of the first through hole is colinear with an axis of the second through hole.

[0014] Optionally, the inclination angle of the truncated cone-shaped generatrix relative to the axis of the first through hole is 30° to 70°;

[0015] and / or,

[0016] The length of the truncated cone-shaped generatrix is ​​1 / 3 to 1 / 2 of the depth of the through hole.

[0017] Optionally, the thickness of the elastic layer is 1 / 10-1 / 15 of the width of the through hole.

[0018] In a second aspect, an embodiment of the present invention provides a method for manufacturing a TGV adapter plate, comprising:

[0019] providing a glass substrate;

[0020] A plurality of through holes are formed on the glass substrate, wherein the through holes penetrate along the thickness direction of the glass substrate, and the diameter of the upper end of the through hole is larger than the diameter of the lower end;

[0021] forming an elastic layer on the inner wall of the through hole;

[0022] A conductive layer is filled in the through hole, and the elastic layer is located between the conductive layer and the inner wall of the through hole.

[0023] Optionally, forming a through hole on the glass substrate includes:

[0024] forming a first through hole and a second through hole on the glass substrate;

[0025] Wherein, the first through hole is located at the upper end of the second through hole;

[0026] The first through hole is in a truncated cone shape, the bottom diameter of the truncated cone is smaller than the top diameter, and is the same as the top diameter of the second through hole;

[0027] The second through hole is columnar, and an axis of the first through hole is colinear with an axis of the second through hole.

[0028] Optionally, the inclination angle of the truncated cone-shaped generatrix relative to the axis of the first through hole is 30° to 70°;

[0029] and / or,

[0030] The length of the truncated cone-shaped generatrix is ​​1 / 3 to 1 / 2 of the depth of the through hole.

[0031] Optionally, forming an elastic layer on the inner wall of the through hole includes:

[0032] The elastic material is uniformly filled onto the hole wall of the through hole, and the thickness of the elastic material filling accounts for 1 / 10-1 / 15 of the width of the through hole.

[0033] Optionally, filling the conductive layer in the through hole includes:

[0034] Plating a seed layer on the surface of the elastic layer;

[0035] The through hole after the seed layer is chemically plated is electroplated to form the conductive layer.

[0036] In a third aspect, an embodiment of the present invention provides a chip, characterized in that it includes the TGV adapter board as described in the first aspect.

[0037] Optionally, also include:

[0038] A first routing layer and a pad, wherein the first routing layer is located on one side of the TGV adapter board, and the pad is located on the other side of the TGV adapter board;

[0039] The first wiring layer is electrically connected to the pad through the conductive layer.

[0040] In the embodiment of the present invention, by providing an elastic layer on the inner wall of the through hole of the glass substrate and then providing a conductive layer, it is possible to avoid direct bonding of the conductive layer to the glass substrate. The elastic layer buffers stress, thereby avoiding breakage of the glass substrate due to excessive local stress in the through hole, thereby increasing the strength and durability of the TGV adapter board. The elastic layer can also buffer external stress, enhance the strength of the TGV adapter board, avoid deformation of the adapter board, improve the overall performance of the TGV adapter board, and enhance the service life of the adapter board. In addition, the diameter of the upper end of the through hole is greater than the diameter of the lower end. By limiting the aperture of the through hole, the arrangement of the conductive layer can be optimized, thereby enhancing the conductive effect of the TGV adapter board. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0042] Figure 1 is a schematic diagram of a TGV adapter board provided by an embodiment of the present invention;

[0043] Figure 2 is a schematic diagram of a through hole of a TGV adapter plate provided by an embodiment of the present invention;

[0044] Figure 3 is a schematic diagram of a TGV adapter plate including an elastic layer provided by an embodiment of the present invention;

[0045] Figure 4 is a schematic diagram of a TGV adapter plate including an elastic layer and a conductor layer provided in an embodiment of the present invention;

[0046] Figure 5 is a flow chart of a method for manufacturing a TGV adapter plate provided by an embodiment of the present invention;

[0047] Figure 6 It is a schematic diagram of a TGV adapter board and a first routing layer of a chip provided in an embodiment of the present invention;

[0048] Figure 7 It is a schematic diagram of a TGV adapter board, a first routing layer and a pad of a chip provided in an embodiment of the present invention;

[0049] Reference numerals:

[0050] 1. glass substrate; 11. through hole; 111. first through hole; 112. second through hole;

[0051] 2. Elastic layer;

[0052] 3. Conductive layer;

[0053] 4. First wiring layer; 41. First wiring layer conductive layer; 42. First wiring layer insulating layer;

[0054] 51. pad conductive layer; 52. pad insulating layer. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] Please refer to Figure 1-Figure 4 , an embodiment of the present invention provides a TGV adapter board, including:

[0057] A glass substrate 1, wherein a plurality of through holes 11 are provided on the glass substrate 1; the through holes 11 penetrate along the thickness direction of the glass substrate 1, and the upper end diameter of the through holes 11 is larger than the lower end diameter;

[0058] The elastic layer 2 is arranged on the inner wall of the through hole 11;

[0059] The conductive layer 3 is filled in the through hole 11 , and the elastic layer 2 is located between the conductive layer 3 and the inner wall of the through hole 11 .

[0060] In the embodiment of the present invention, by arranging the elastic layer 2 on the inner wall of the through hole 11 of the glass substrate 1 and then arranging the conductive layer 3, it is possible to avoid the conductive layer 3 being directly combined with the glass substrate 1, and by buffering the stress through the elastic layer 2, it is possible to avoid the glass substrate 1 being broken due to excessive local stress in the through hole 11, thereby increasing the strength and durability of the TGV adapter board; the elastic layer 2 can also buffer external stress, enhance the strength of the TGV adapter board, avoid deformation of the adapter board, improve the overall performance of the TGV adapter board, and enhance the service life of the adapter board, and the diameter of the upper end of the through hole 11 is greater than the diameter of the lower end. By limiting the aperture of the through hole 11, the arrangement of the conductive layer 3 can be optimized, thereby enhancing the conductive effect of the TGV adapter board.

[0061] Please refer to Figure 1 and Figure 2 In the embodiment of the present invention, optionally, each of the through holes 11 includes:

[0062] A first through hole 111 and a second through hole 112, wherein the first through hole 111 is located at an upper end of the second through hole 112 and communicates with the second through hole 112;

[0063] The first through hole 111 is in a truncated cone shape, the bottom diameter of the truncated cone is smaller than the top diameter, and is the same as the top diameter of the second through hole 112;

[0064] The second through hole 112 is columnar, and the axis of the first through hole 111 is colinear with the axis of the second through hole 112 .

[0065] In an embodiment of the present invention, the first through hole 111 is in a truncated cone shape, the second through hole 112 is in a columnar shape, and the axis of the first through hole 111 is collinear with the axis of the second through hole 112, that is, the first through hole 111 and the second through hole 112 are combined into a funnel shape. The funnel-shaped through hole 11 can better distribute the conductive material in the through hole 11 and enhance the conductive effect of the adapter plate.

[0066] Please refer to Figure 2 In the embodiment of the present invention, optionally, the inclination angle θ of the truncated cone-shaped generatrix relative to the axis of the first through hole 111 is 30° to 70°;

[0067] and / or,

[0068] The length of the truncated cone-shaped generatrix is ​​1 / 3 to 1 / 2 of the depth of the through hole 11 .

[0069] In the embodiment of the present invention, please refer to Figure 2The inclination angle of the truncated cone-shaped busbar relative to the axis of the first through hole 111 can be 30° to 70°. By limiting the angle of the first through hole 111, the problem of uneven distribution of conductive materials caused by an angle that is too small or too large, which in turn leads to poor conductive effect, can be avoided. In the embodiment of the present invention, by limiting the shape of the first through hole 111, a good conductive effect of the adapter plate can be ensured.

[0070] Furthermore, the length of the truncated cone-shaped busbar is 1 / 3 to 1 / 2 of the depth of the through hole 111. By limiting the depth of the first through hole 111, deformation of the TGV adapter plate caused by the excessive proportion of the first through hole 111 is avoided. The structural stability of the adapter plate is enhanced while ensuring good conductive effect, thereby increasing its service life.

[0071] Please refer to Figure 3 In the embodiment of the present invention, optionally, the thickness of the elastic layer 2 is 1 / 10-1 / 15 of the width of the through hole 11.

[0072] In the embodiment of the present invention, the thickness of the elastic layer 2 is limited to 1 / 10-1 / 15 of the width of the through hole 11. On the one hand, it is prevented that the elastic layer 2 is too thin, resulting in poor protection effect, and on the other hand, it is prevented that the elastic layer 2 is too thick, resulting in insufficient filling of the conductive layer 3. The buffering effect of the elastic layer 2 is enhanced by limiting the thickness of the elastic layer.

[0073] Furthermore, the elastic layer 2 can be made of a material that has both elasticity and insulation functions. The insulation of the material can better avoid direct contact between the conductive material and the glass substrate 1, thereby enhancing the structural strength of the adapter plate. The elastic layer 2 can be made of polyimide (PI) material, etc. PI also has thermal stability, which can further enhance the stability of the elastic layer 2.

[0074] Furthermore, the adhesion between the elastic layer 2 and the conductive layer 3 can be enhanced by increasing the roughness of the surface of the elastic layer 2 .

[0075] Please refer to Figure 1-Figure 5 The embodiment of the present invention further provides a method for manufacturing a TGV adapter plate, comprising:

[0076] Step 21: Providing a glass substrate 1;

[0077] Step 22: forming a plurality of through holes 11 on the glass substrate 1, wherein the through holes 11 penetrate the glass substrate 1 in a thickness direction, and the upper end diameter of the through holes 11 is larger than the lower end diameter;

[0078] Step 23: forming an elastic layer 2 on the inner wall of the through hole 11;

[0079] Step 24 : Filling the through hole 11 with a conductive layer 3 , wherein the elastic layer 2 is located between the conductive layer 3 and the inner wall of the through hole 11 .

[0080] In an embodiment of the present invention, firstly, a plurality of through holes 11 are formed on a provided glass substrate 1 along a thickness direction, and then an elastic layer 2 is formed on an inner wall of the through hole 11 to buffer external stress, thereby enhancing the strength of the TGV adapter board, avoiding deformation of the adapter board, and improving the overall performance of the TGV adapter board. Finally, a conductive layer 3 is filled in the through hole 11 having the elastic layer 2, thereby avoiding direct contact between the conductive layer 3 and the glass substrate 1, avoiding breakage of the glass substrate 1 due to excessive local stress in the through hole 11, further enhancing the strength of the adapter board, and enhancing the service life of the adapter board. In addition, the diameter of the upper end of the through hole 11 is greater than the diameter of the lower end. By limiting the aperture of the through hole 11, the arrangement of the conductive layer 3 can be optimized, thereby enhancing the conductive effect of the TGV adapter board.

[0081] Please refer to Figure 1 and Figure 2 In the embodiment of the present invention, optionally, forming the through hole 11 on the glass substrate 1 includes:

[0082] Forming a first through hole 111 and a second through hole 112 on the glass substrate 1;

[0083] Wherein, the first through hole 111 is located at the upper end of the second through hole 112;

[0084] The first through hole 111 is in a truncated cone shape, the bottom diameter of the truncated cone is smaller than the top diameter, and is the same as the top diameter of the second through hole 112;

[0085] The second through hole 112 is columnar, and the axis of the first through hole 111 is colinear with the axis of the second through hole 112 .

[0086] In the embodiment of the present invention, optionally, the through hole 11 may be formed by laser etching, sandblasting, mechanical drilling, dry etching, wet etching, etc.

[0087] Optionally, the first through hole 111 is in a truncated cone shape, the second through hole 112 is in a columnar shape, and the axis of the first through hole 111 is collinear with the axis of the second through hole 112, that is, the first through hole 111 and the second through hole 112 are combined into a funnel shape. The funnel-shaped through hole 11 can better distribute the conductive material in the through hole 11 and enhance the conductive effect of the adapter plate.

[0088] Please refer to Figure 2 In the embodiment of the present invention, optionally, the inclination angle of the truncated cone-shaped generatrix relative to the axis of the first through hole 111 is 30° to 70°;

[0089] and / or,

[0090] The length of the truncated cone-shaped generatrix is ​​1 / 3 to 1 / 2 of the depth of the through hole 11 .

[0091] In the embodiment of the present invention, please refer to Figure 2 The inclination angle of the truncated cone-shaped busbar relative to the axis of the first through hole 111 can be 30° to 70°. By limiting the angle of the first through hole 111, the problem of uneven distribution of conductive materials caused by an angle that is too small or too large, which in turn leads to poor conductive effect, can be avoided. In the embodiment of the present invention, by limiting the shape of the first through hole 111, a good conductive effect of the adapter plate can be ensured.

[0092] Furthermore, the length of the truncated cone-shaped busbar is 1 / 3 to 1 / 2 of the depth of the through hole 111. By limiting the depth of the first through hole 111, deformation of the TGV adapter plate caused by the excessive proportion of the first through hole 111 is avoided. The structural stability of the adapter plate is enhanced while ensuring good conductive effect, thereby increasing its service life.

[0093] Please refer to Figure 3 In the embodiment of the present invention, optionally, forming the elastic layer 2 on the inner wall of the through hole 11 includes:

[0094] The elastic material is uniformly filled onto the hole wall of the through hole 11 , and the thickness of the elastic material filled is 1 / 10-1 / 15 of the width of the through hole 11 .

[0095] In the embodiment of the present invention, the thickness of the elastic layer 2 is limited to 1 / 10-1 / 15 of the width of the through hole 11. On the one hand, it is prevented that the elastic layer 2 is too thin, resulting in poor protection effect, and on the other hand, it is prevented that the elastic layer 2 is too thick, resulting in insufficient filling of the conductive layer 3. The buffering effect of the elastic layer 2 is enhanced by limiting the thickness of the elastic layer.

[0096] Furthermore, in the embodiment of the present invention, the elastic material can be evenly filled onto the hole wall of the through hole 11 by spraying.

[0097] Furthermore, the elastic layer 2 can be made of a material that has both elasticity and insulation functions. The insulation of the material can better avoid direct contact between the conductive material and the glass substrate 1, thereby enhancing the structural strength of the adapter plate. The elastic layer 2 can be made of polyimide (PI) material, Ajinomoto Build-up Film (ABF) and an adhesive layer, etc. PI also has thermal stability, which can further enhance the stability of the elastic layer 2 when filling the conductive layer 3.

[0098] Furthermore, the roughness of the surface of the elastic layer 2 may be increased by means of chemical roughening and plasma treatment, so as to enhance the adhesion between the elastic layer 2 and the conductive layer 3 .

[0099] Please refer to Figure 4 In the embodiment of the present invention, optionally, filling the conductive layer 3 in the through hole 11 includes:

[0100] Plating a seed layer on the surface of the elastic layer 2;

[0101] The through hole 11 after the chemical plating of the seed layer is electroplated to form the conductive layer 3 .

[0102] In an embodiment of the present invention, a method for forming a conductive layer 3 is provided. Optionally, a seed layer can be sputtered on the surface of the elastic layer 2 first. The seed layer is used to absorb copper ions in the electroplating solution during the electroplating process. The glass substrate 1 is immersed in a dilute sulfuric acid solution for activation, and then the activated glass substrate 1 is placed in an electroplating cathode tank for electroplating, wherein the current intensity and time of the electroplating are set according to product requirements. The through hole 11 electroplated by the electroplating method in the embodiment of the present invention can carry a larger current and enhance the strength of the TGV adapter board.

[0103] Furthermore, in an embodiment of the present invention, the seed layer can be titanium-copper, and the material of the conductive layer 3 can be copper, which is not limited in the present invention. Among them, copper has a low resistivity and cost, so when used as the material of the conductive layer 3 of the TGV adapter plate, it can have a better conductive effect and reduce the production cost.

[0104] Please refer to Figure 1-Figure 4 An embodiment of the present invention further provides a chip, comprising the TGV adapter board as described in any one of the above items.

[0105] The chip provided in the embodiment of the present invention includes the TGV adapter board as described in any of the above items, which can prevent the conductive layer 3 in the TGV adapter board included in the chip from directly contacting the glass substrate 1, and avoid the glass substrate 1 from being broken due to excessive local stress in the through hole 11, thereby enhancing the strength and overall performance of the chip and enhancing the service life of the chip.

[0106] Please refer to Figure 6 and Figure 7 In the embodiment of the present invention, optionally, it further includes:

[0107] A first wiring layer 4 and a pad 5, wherein the first wiring layer 4 is located on one side of the TGV adapter board, and the pad 5 is located on the other side of the TGV adapter board;

[0108] The first wiring layer 4 is electrically connected to the pad 5 through the conductive layer 3 .

[0109] Please refer to Figure 6The first routing layer 4 is a re-distributed layer (RDL), with a minimum thickness of L / S2um. The re-distributed layer includes a first routing layer conductive layer 41 and a first routing layer insulating layer 42. The material of the first routing layer insulating layer 42 is PI, and the material of the conductive layer 3 is copper. The resistivity and cost of copper are both low. Therefore, when used as the material of the first routing layer conductive layer 41, it can have a better conductive effect and can reduce the manufacturing cost of the chip.

[0110] Furthermore, the first wiring layer conductive layer 41 may be formed by spin coating PI on the glass substrate 1 multiple times and performing photolithography.

[0111] The pad includes a pad conductive layer 51 and a pad insulating layer 52, which is a ball grid array (BGA) packaging layer. The pad is connected to the conductive layer in the adapter board through the via hole of the insulating layer grid. The packaging area packaged by the pad 5 is small, the reliability is high, the electrical performance is good, and the overall cost is low, which can further enhance the overall performance of the chip and reduce costs.

[0112] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0113] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0114] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A TGV adapter plate, characterized in that: include: A glass substrate having a plurality of through holes formed thereon; the through holes extending through the glass substrate in a thickness direction, the upper end diameter of the through holes being larger than the lower end diameter; an elastic layer, disposed on the inner wall of the through hole; The conductive layer is filled in the through hole, and the elastic layer is located between the conductive layer and the inner wall of the through hole.

2. The TGV adapter plate according to claim 1, characterized in that: Each of the through holes comprises: a first through hole and a second through hole, wherein the first through hole is located at an upper end of the second through hole and communicates with the second through hole; The first through hole is in a truncated cone shape, the diameter of the bottom end of the truncated cone is smaller than the diameter of the top end, and is the same as the diameter of the top end of the second through hole; The second through hole is columnar, and an axis of the first through hole is collinear with an axis of the second through hole.

3. The TGV adapter plate according to claim 2, characterized in that: The inclination angle of the truncated cone-shaped generatrix relative to the axis of the first through hole is 30° to 70°; and / or, The length of the truncated cone-shaped busbar is 1 / 3 to 1 / 2 of the depth of the through hole.

4. The TGV adapter plate according to claim 1, characterized in that: The thickness of the elastic layer is 1 / 10-1 / 15 of the width of the through hole.

5. A method for manufacturing a TGV adapter plate, characterized in that: include: providing a glass substrate; forming a plurality of through holes on the glass substrate, wherein the through holes penetrate along the thickness direction of the glass substrate, and the diameter of the upper end of the through holes is larger than the diameter of the lower end; forming an elastic layer on the inner wall of the through hole; A conductive layer is filled in the through hole, and the elastic layer is located between the conductive layer and the inner wall of the through hole.

6. The method according to claim 5, characterized in that The forming of a through hole on the glass substrate comprises: forming a first through hole and a second through hole on the glass substrate; Wherein, the first through hole is located at the upper end of the second through hole; The first through hole is in a truncated cone shape, the diameter of the bottom end of the truncated cone is smaller than the diameter of the top end, and is the same as the diameter of the top end of the second through hole; The second through hole is columnar, and an axis of the first through hole is collinear with an axis of the second through hole.

7. The method according to claim 6, characterized in that The inclination angle of the truncated cone-shaped generatrix relative to the axis of the first through hole is 30° to 70°; and / or, The length of the truncated cone-shaped busbar is 1 / 3 to 1 / 2 of the depth of the through hole.

8. The method according to claim 5, characterized in that The forming of the elastic layer on the inner wall of the through hole comprises: The elastic material is evenly filled onto the hole wall of the through hole, and the thickness of the elastic material filling is 1 / 10-1 / 15 of the width of the through hole.

9. The method according to claim 5, characterized in that Filling the conductive layer in the through hole comprises: chemically plating a seed layer on the surface of the elastic layer; The through hole after the seed layer is electroplated is electroplated to form the conductive layer.

10. A chip, characterized in that: It comprises the TGV adapter plate according to any one of claims 1 to 4.

11. The chip according to claim 10, characterized in that Also includes: A first routing layer and a pad, wherein the first routing layer is located on one side of the TGV adapter board, and the pad is located on the other side of the TGV adapter board; The first wiring layer is electrically connected to the pad through the conductive layer.

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