Package and method of forming the same

Abstract

Embodiments of the present application provide a package, characterized by comprising: a silicon wafer; a molding compound surrounding the silicon wafer and embedding the silicon wafer therein; wherein the silicon wafer has a first surface, and wherein the first surface has first functional groups bonded with second functional groups of a bridging agent. The package provided by the present application tightly bonds the molding compound, the silicon surface and the copper pillar firmly, effectively avoiding the delamination or interface damage problem between the heterogeneous interfaces, and also can form a clear mark between the ink and the silicon surface / molding compound through chemical covalent bond. Embodiments of the present application also relate to a method of forming a package.

Description

Technical Field

[0001] Embodiments of this application relate to packages and methods of forming the same. Background Technology

[0002] In the M-series manufacturing process, laser marking is performed at the end. Figure 1 In the 1)) operation, however, due to the long laser engraving time and high UPH (units per hour) required for laser marking, if inkjet ( Figure 2 While ink marking can improve marking speed, the different chemical structures and physical properties of ink and silicon (silicon has a smooth surface) result in different adhesion strengths between them. This difference can easily lead to broken characters or unclear fonts.

[0003] In encapsulated components, delamination and illegible / damaged marking characters have long been a problem after back-side thin-film coating, molding compound (EMC), and laser marking. Current solutions involve inkjet printing or replacement. However, due to the differences in chemical structure and physical properties between ink, molding compound, and silicone, their adhesive strengths inevitably differ. This difference is the primary cause of delamination and illegible / damaged marking characters. Furthermore, delamination / interface damage issues also exist between heterogeneous interfaces such as those between silicone and molding compound. Therefore, a new solution is urgently needed to overcome these problems. Summary of the Invention

[0004] This application provides a package comprising: a silicon wafer; a molding compound surrounding the silicon wafer and embedding the silicon wafer therein; wherein the silicon wafer has a first surface, and wherein the first surface has a first functional group bonded to a second functional group of a bridging agent.

[0005] In some embodiments, the bridging reagent has a second functional group at both ends.

[0006] In some embodiments, the package further includes a connector for connecting to a first surface of the silicon wafer, wherein the surface of the connector has the first functional group, and the connection between the silicon wafer and the connector is achieved by bonding the second functional group of the bridging agent to the first functional group of the first surface of the silicon wafer and the surface of the connector.

[0007] In some embodiments, the bond is a covalent bond connection.

[0008] In some embodiments, the first functional group is an OH functional group.

[0009] In some embodiments, the second functional group is a COOH functional group.

[0010] In some embodiments, the bridging agent comprises glutaric acid.

[0011] In some embodiments, the device having a surface with a first functional group comprises an ink.

[0012] In some embodiments, the package further comprises a copper pillar disposed below the silicon wafer and embedded within the molding compound, wherein the copper pillar has a surface with the first functional group, the molding compound also has a surface with the first functional group, and wherein the bridging agent bonds between the first surface of the silicon wafer, the surface of the molding compound, and the surface of the copper pillar.

[0013] The present application also provides a method of forming a package, comprising: providing a molding wafer having a silicon surface; surface treating the molding wafer to impart a first functional group to the silicon surface; and placing the treated molding wafer in a solution comprising a bridging agent, wherein the bridging agent has a second functional group that bonds with the first functional group.

[0014] In some embodiments, the bridging agent has the second functional group at both ends.

[0015] In some embodiments, the surface treating comprises oxygen plasma treatment.

[0016] In some embodiments, the molding wafer comprises a silicon wafer and a molding compound surrounding the silicon wafer,

[0017] wherein the surface treating also imparts a first functional group to a surface of the molding compound.

[0018] In some embodiments, the package further comprises joining the silicon surface with the first functional group to a surface of a connector having the first functional group, the joining being achieved by bonding the second functional group of the bridging agent to the first functional group of the silicon surface and the first functional group of the surface of the connector.

[0019] In some embodiments, the bonding is a covalent bond.

[0020] In some embodiments, the surface treating comprises soaking the molding wafer in a first solution to oxidize the silicon surface to produce the first functional group.

[0021] In some embodiments, the first solution comprises an aqueous solution of lithium aluminum hydride.

[0022] In some embodiments, the molded wafer comprises a silicon wafer, a molding compound surrounding the silicon wafer, and copper pillars disposed below the silicon wafer and embedded in the molding compound, wherein the soaking further comprises permeating the first solution into a gap between the molding compound, the silicon wafer, and the copper pillars.

[0023] In some embodiments, the bridging agent bonds between the silicon wafer, the molding compound, and the copper pillars.

[0024] In some embodiments, the first functional group is an OH functional group.

[0025] In some embodiments, the second functional group is a COOH functional group.

[0026] In some embodiments, the bridging agent comprises glutaric acid.

[0027] The package provided herein uses a bridging agent as a linker to covalently bond with the ink, molding compound, copper pillars, and silicon surface. Because the bridging agent bonds not only penetrate into the gap between the components of the package to make the molding compound, silicon surface, and copper pillars tightly and firmly combined to effectively avoid the problem of delamination or interface damage between heterogeneous interfaces, but also form a clear mark between the ink and the silicon surface / molding compound through chemical covalent bond. BRIEF DESCRIPTION OF DRAWINGS

[0028] Various aspects of the application can be best understood from the following detailed description when read with the accompanying drawings in which: It should be noted that the various components are not drawn to scale. In fact, the dimensions of the various components can be arbitrarily increased or decreased for the sake of clarity in discussion.

[0029] Figure 1 is a laser marking operation on a silicon surface in the prior art;

[0030] Figure 2 is an inkjet on a silicon surface in the prior art;

[0031] Figure 3A and Figure 3B denotes a surface treated with oxygen plasma;

[0032] Figure 4 is a schematic of connecting a silicon functional surface with an ink through a bridging agent;

[0033] Figure 5 is a reaction of a surface of a molded wafer in an aqueous solution of lithium aluminum hydride;

[0034] Figure 6 is a reaction mechanism of a molded wafer in an aqueous solution of lithium aluminum hydride;

[0035] Figure 7 is the bonding of the molded wafer after treatment with a lithium aluminum hydride aqueous solution with a bridging reagent;

[0036] Figures 8-1 to 8-12 A process flow for fabricating a package is shown according to some embodiments;

[0037] Figure 9 is an inkjet mark with a certain thickness on the silicon functional surface;

[0038] Figures 10-1 to 10-11 A process flow for fabricating a package is shown according to some embodiments;

[0039] Figures 11-1 to 11-10 A process flow for fabricating a package is shown according to some embodiments;

[0040] Figure 12 A mechanism of the silicon-based oxygen plasma treatment process is shown; and

[0041] Figure 13 A principle of the molding compound-based oxidation reaction is shown. DETAILED DESCRIPTION

[0042] The following disclosure provides many different embodiments, or examples, for implementing different characteristics of the application. Specific examples of components and arrangements are described below to simplify the present application. These are, of course, merely examples and are not intended to limit the application in any way.

[0043] The package provided in the present application uses a bridging reagent as a linker to covalently bond with the ink, molding compound, copper pillar, and silicon surface. Because the bridging reagent bonds not only penetrate into the gaps between the components of the package to firmly and tightly bind the molding compound, silicon surface, and copper pillar, effectively avoiding the problem of delamination or interface damage between the heterogeneous interfaces, but also forms a clear mark between the ink and the silicon surface / molding compound through chemical covalent bonds.

[0044] The present application provides a package and a method of forming the same, which covalently bonds between a first surface (i.e., a silicon functional surface) of a silicon wafer and a connecting member (such as ink, molding compound, and copper pillar) so that the connecting member is firmly and tightly bound to the silicon functional surface.

[0045] One method is to perform an oxygen plasma treatment process on the silicon surface, specifically by first treating the silicon surface to have a first functional group (e.g., an OH functional group), for example, as shown in Figure 3AAs shown, the surface 101s of the silicon wafer 101 is subjected to oxygen plasma treatment (O2 plasma treatment) ① to make the silicon surface 101s have OH functional groups, thereby forming a silicon functional surface 101gs (i.e., the functional surface refers to the surface with OH functional groups after treatment), as shown in Figure 3B As shown, the surface 101s of the silicon wafer 101 and the surface 102s of the copper pillar 102 are subjected to oxygen plasma treatment ① to make the surface 101s of the silicon wafer 101 and the surface 102s of the copper pillar 102 have OH functional groups, thereby forming a silicon functional surface 101gs and a copper pillar functional surface 102gs; then, a bridging agent containing a second functional group (e.g., COOH functional group) bonded to the first functional group is added in the connecting member such as the ink 2, and when the connecting member is connected to the silicon functional surface (e.g., when the ink is sprayed on the silicon functional surface), the second functional groups at both ends of the bridging agent and the OH functional groups of the silicon functional surface and the surface of the connecting member are subjected to condensation reaction to form covalent bond, wherein the bridging agent is selected from, but not limited to, glutaric acid, adipic acid, etc., as long as both ends have the second functional group bonded to the first functional group.

[0046] Referring to Figure 4 , the covalent bond of the COOH functional group of the bridging agent ② and the OH functional groups of the silicon functional surface 101gs and the surface of the ink 2 is shown, and it can be seen that the OH functional groups of the surface of the ink 2 are bonded to the OH functional groups of the silicon functional surface 101gs through the COOH functional groups of the bridging agent ②, so that the ink 2 can be well attached to the silicon functional surface 101s, and a clear mark is formed between the ink 2 and the silicon functional surface 101gs (or the molding compound 103, which will be described in more detail below) through chemical covalent bond.

[0047] In addition, another method is to use an aqueous solution of lithium aluminum hydride treatment process, which can penetrate into the gaps between the various components of the package;

[0048] In addition to connecting the connecting member such as the ink 2 to the silicon functional surface 101gs, the bridging agent ② can also penetrate into the gaps between the various components of the package to bond the functional surfaces of the connecting members such as the molding compound 102 and the copper pillar 102 to the silicon functional surface; specifically, referring to Figure 5 , Figure 5 is the reaction of the various surfaces of the molded wafer 10 in the aqueous solution of lithium aluminum hydride ③, and in Figure 5 , the structure of the conventional surface 103s of the molding compound 103 is shown, and the molding compound 103 with this surface structure is immersed in the aqueous solution of lithium aluminum hydride ③ to react, so that the surface of the molding compound 103 has a first functional group (i.e., OH functional group), thereby forming a functional surface 103gs of the molding compound 103, and in addition, referring toFigure 7 The molding wafer 10 is treated by a lithium aluminum hydride aqueous solution ③, which can penetrate into the gap between the molding compound 103, the silicon wafer 101 and the copper pillar 102, and oxidize the entire surface to generate a first functional group (i.e., OH functional group), thereby forming a corresponding silicon functional surface 101gs and molding compound functional surface 103gs. Then, the molding wafer 10 is immersed in a solution of a bridging agent ② (such as glutaric acid), and the second functional group (COOH functional group) at both ends of the bridging agent ② is covalently bonded to the molding compound 103, the silicon wafer 101 and the copper pillar 102, respectively, so that the bonding between the molding compound 103, the silicon wafer 101 and the copper pillar 102 is more firm. In this way, the adhesion between the heterogeneous interfaces can be increased and interface damage and delamination can be avoided.

[0049] Figure 6 The reaction mechanism of the molding wafer in the lithium aluminum hydride aqueous solution is shown. First, the molding wafer 10 with a conventional surface structure reacts with lithium aluminum hydride ④ to generate oxygen dangling bonds (O - ). Then, the oxygen dangling bonds (O - ) react with water ⑤ to generate OH functional groups on the surface of the molding wafer, thereby forming a molding compound functional surface 103gs.

[0050] Referring again to Figure 7 , the specific operation steps of the lithium aluminum hydride aqueous solution process are as follows: the molding wafer 10 shown in Figure 7 is immersed in a tank containing a lithium aluminum hydride aqueous solution ③, so that the relevant surfaces of the molding wafer 10 are oxidized. After the oxidation reaction, the molding wafer is washed with water and dried to obtain a molding compound functional surface 103gs and a structure with OH functional groups in the gap between the molding compound 103, the silicon wafer 101 and the copper pillar 102 (i.e., the surfaces of each component in the gap are formed into corresponding functional surfaces 101gs, 103gs, etc.). After obtaining the structure with OH functional groups, the molding wafer is immersed in a solution containing a bridging agent ② (such as glutaric acid) to obtain a molding wafer in which the gap between the molding compound 103, the silicon wafer 101 and the copper pillar 102 is covalently bonded by the bridging agent ②.

[0051] The following examples illustrate the formation process of the package of the present application in detail.

[0052] Example 1

[0053] Figures 8-1 to 8-12 The process flow for preparing a package according to some embodiments is shown. Specifically, referring to Figure 8-1A die 100 for attachment is provided, comprising a silicon functional surface 101gs and a copper pillar functional surface 102gs formed by oxygen plasma treatment (or by aqueous solution treatment of lithium aluminum hydride) (i.e., the surface has OH functional groups, the specific structure of which is shown in the dashed box); as Figure 8-2 As shown, a die 100 having functional surfaces 101gs and 102gs is attached to a carrier 105 via an adhesive layer 104. The carrier 105 can be a glass carrier substrate, a ceramic carrier substrate, etc., and the adhesive layer 104 can be formed of a polymer-based material, which can be removed from the structure above along with the carrier 105 or removed separately. In some embodiments, the adhesive layer 104 is a heat-release material based on epoxy resin that loses its adhesiveness upon heating, such as a photothermal conversion (LTHC) release coating. In other embodiments, the adhesive layer 104 can be a UV adhesive that loses its adhesiveness upon exposure to UV light. The adhesive layer 104 can be dispensed as a liquid and cured, and can be a laminated film, etc., laminated onto the carrier 105. The top surface of the adhesive layer 104 can be flush and can have a high degree of planarity.

[0054] like Figure 8-3 As shown, a molding compound 103 is formed over the attached die. The molding compound 103 can be applied by compression molding, transfer molding, etc., and is formed over the carrier 105, thereby burying or covering the die 100 attached to the carrier 105. In some embodiments, the molding compound 103 can be applied in liquid or semi-liquid form and then cured.

[0055] After that, as Figure 8-4 As shown, the carrier 105 can be detached by projecting light, such as laser light or ultraviolet (UV) light, onto the adhesive layer 104; after the carrier 105 is detached, as... Figure 8-5 As shown, the adhesive layer 104 under the silicon wafer 101 is removed by projecting light such as laser or ultraviolet (UV) light onto the adhesive layer 104. Since the surface is treated before being bonded to the carrier, the subsequently attached adhesive layer 104 and molding compound 103 are bonded in the form of covalent bonds (e.g., by a bridging agent).

[0056] exist Figure 8-6 In China, Figure 8-5 The front side of the resulting structure is subjected to a planarization process ⑥, so that the top surface of the molding compound 103 and the top surface of the copper pillar 102 are flush. In some embodiments, the planarization process ⑥ can be, for example, chemical mechanical polishing (CMP), grinding process, etc.

[0057] exist Figure 8-7In this process, a redistribution layer (RDL) 106 and under-bump metallization (UBM) 107 are formed on the flat top surfaces of the molding compound 103 and the copper pillar 102; the redistribution layer 106 includes a dielectric layer 1061 and a metallization pattern 1062. Figure 8-7 In this process, a metallization pattern 1062 can be formed on the flat top surface of the molding compound 103 and the copper pillar 102. As an example of forming the metallization pattern 1062, a seed layer is formed above the flat top surface of the molding compound 103 and the copper pillar 102. In some embodiments, the seed layer is a metal layer, which can be a single layer or a composite layer comprising multiple sublayers formed of different materials. In some embodiments, the seed layer includes a titanium layer and a copper layer above the titanium layer. The seed layer can be formed using, for example, physical vapor deposition (PVD). A photoresist (not shown) is then formed and patterned on the seed layer. The photoresist can be formed by spin coating or the like and can be exposed to light for patterning. The pattern of the photoresist corresponds to the metallization pattern 1062. Patterning forms openings through the photoresist to expose the seed layer. A conductive material is formed in the openings of the photoresist and on the exposed portion of the seed layer. The conductive material can be formed by plating (such as electroplating, electroless plating, etc.). The conductive material can include metals such as copper, titanium, tungsten, aluminum, etc. Then, the photoresist and the portion of the seed layer on which no conductive material is formed are removed. The photoresist can be removed by an acceptable ashing or stripping process, such as using oxygen plasma. Once the photoresist is removed, the exposed portion of the seed layer is removed, such as by using an acceptable etching process, such as by wet etching or dry etching. The remaining portion of the seed layer and conductive material forms a metallization pattern 1062. A dielectric layer 1061 is formed on the metallization pattern 1062. The bottom surface of the dielectric layer 1061 contacts the flat top surface of the molding compound 103 and the copper pillar 102. In some embodiments, the dielectric layer 1061 is formed of a polymer, such as polyimide. In other embodiments, the dielectric layer 1061 is formed of a nitride, such as silicon nitride; an oxide, such as silicon oxide; etc. The dielectric layer 1061 can be formed by spin coating, lamination, chemical vapor deposition, etc., or combinations thereof. The dielectric layer 1061 is then patterned to form via openings that expose portions of the metallization pattern 1062. The patterning can be formed by an acceptable process, such as etching using, for example, anisotropic etching. Subsequently, under-bump metal (UBM) 107 is formed in the via opening. The UBM can be formed from the same material and using the same process as the metallization pattern 1062, which will not be described in detail here.

[0058] exist Figure 8-8 In the process, bumps 108 are formed in the opening surrounded by under bump metal (UBM) 107 by ball bonding process. Bumps 108 may include conductive materials such as solder, copper, aluminum, gold, nickel, silver, palladium, tin, or combinations thereof, and may be formed by sputtering, printing, electroplating, electroless plating, chemical vapor deposition, etc.

[0059] In Figure 8-9 , a protective tape 109 is formed on the bump 108, which can be another carrier similar to the carrier 105, and is formed by pasting, spin coating, physical vapor deposition, etc. After the protective tape 109 is formed, the resulting structure is flipped upside down.

[0060] In Figure 8-10 , the back side of the resulting structure in Figure 8-9 is subjected to a planarization process ⑥ so that the silicon surface 101s of the silicon wafer 101 is exposed, which is described in detail above and will not be repeated here.

[0061] In Figure 8-11 , the exposed silicon surface 101s is subjected to an oxygen plasma treatment ① so that the silicon surface 101s is provided with OH functional groups, thereby forming a silicon functional surface 101gs; in Figure 8-12 , the ink 2 is sprayed on the silicon functional surface 101gs by a bridging agent ②, so that the ink 2 is uniformly attached to the silicon functional surface 101gs, and a clear mark (such as the ink mark 104 shown in Figure 9 ) is formed on the silicon functional surface 101s. In this embodiment, oxygen plasma treatment or aqueous lithium aluminum hydride treatment process can be performed on each surface as needed at each step, thereby enhancing the bonding of the heterojunction.

[0062] Embodiment 2

[0063] Figures 10-1 to 10-11 A process flow for preparing a package according to other embodiments is shown. Specifically, in Figure 10-1 , a die 100 for attachment is provided, which similarly includes a silicon functional surface 101gs and a copper pillar functional surface 102gs formed by an oxygen plasma treatment (or by an aqueous lithium aluminum hydride treatment) (i.e., the surfaces are provided with OH functional groups, the specific structure is shown in the dashed box); in Figure 10-2 , an adhesive layer 104 is laminated on the carrier 105, and the materials and formation methods of the adhesive layer 104 and the carrier 105 are the same as described in Figure 8-2 , which will not be repeated here.

[0064] In Figure 10-3 , the die 100 with the silicon functional surface 101gs and the copper pillar functional surface 102gs is attached to the carrier 105 (by covalent bond bonding to the adhesive layer 104 on the carrier 105 through the use of a bridging agent); in Figure 10-4 , the resulting structure in Figure 10-3 is subjected to a pre-baking ⑦, which can be performed in any environment (such as air) at a suitable temperature (such as 30-50°C).

[0065] In Figure 10-5 , a molding compound 103 (adhered to the carrier 105 by a bonding layer 104 that is joined to the carrier 105 by covalent bond bonding using a bridging agent) is formed over the resulting structure in Figure 10-4 , which is formed in the same manner as described in Figure 8-3 , which is not repeated here.

[0066] After the molding compound 103 is formed, the carrier 105 is debonded as shown in Figure 10-6 ; thereafter, the bonding layer 104 (which is joined to the die by covalent bond bonding using a bridging agent) is removed as shown in Figure 10-7 ; the methods of debonding the carrier 105 and removing the bonding layer 104 are the same as described in Figure 8-4 and Figure 8-5 , respectively, which are not repeated here.

[0067] In Figure 10-8 , a backside lamination process ⑧ is performed to form a lamination layer 110 on the backside of the die 100, which is a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer, a combination thereof, and / or other suitable material layer formed by a lamination process.

[0068] In Figure 10-9 , a post-molding cure process ⑨ is performed on the structure, which can be performed in any suitable environment (such as, for example, atmospheric air) and at a suitable temperature (such as, for example, room temperature, 40-50°C, etc.).

[0069] In Figure 10-10 , a planarization process ⑥ is performed on the front side of the resulting structure in Figure 10-9 , such that the top surface of the copper pillar 102 and the top surface of the molding compound 103 are flush; the planarization process ⑥ is the same as described in Figure 8-6 , which is not repeated here.

[0070] Thereafter, in Figure 10-11 , a redistribution layer 106 and an under bump metal 107 are formed on the structure in Figure 10-10 , which are the same as described in Figure 8-7 , which are not repeated here. In this embodiment, oxygen plasma treatment or lithium aluminum hydride aqueous solution treatment process can be performed on various surfaces at various steps as needed to enhance the bonding of the hetero-interfaces.

[0071] Example 3

[0072] Figures 11-1 to 11-10 A process flow for fabricating a package according to yet other embodiments is shown. In Figure 11-1In the process, a bump 108 is formed on the under-bump metal (UBM) 107 using a ball-mounting process. The material and formation method of the bump 108 are the same as those used in the process. Figure 8-8 The descriptions are the same, so they will not be repeated here.

[0073] exist Figure 11-2 In the process, a protective tape 109 is formed on the protrusion 108, and the material and forming method of the protective tape 109 are the same as those used in the process of forming the protrusion 108. Figure 8-9 The description is the same and will not be repeated here. After forming the protective tape 109, flip the structure over.

[0074] exist Figure 11-3 In China, Figure 11-2 A planarization process ⑥ is performed on the back side of the resulting structure, exposing the silicon surface 101s of the silicon wafer 101; Figure 11-4 In the middle, Figure 11-3 The resulting structure was flipped over, and the flipped structure was subjected to ultraviolet (UV) treatment ⑩-1; Figure 11-5 In the middle, Figure 11-4 The resulting structure is flipped upside down, and the exposed silicon surface 101s is subjected to oxygen plasma treatment① to form a silicon functional surface 101gs; Figure 11-6 In the process, ink 2 is sprayed onto the silicon functional surface 101s using bridging reagent ②; Figure 11-7 In the process, ink curing process ⑩-2 is implemented, which can be implemented in any suitable environment (such as the atmosphere) and at a suitable temperature (such as room temperature, 40-50℃, etc.).

[0075] exist Figure 11-8 In Figure 11-7 A planar frame 111 is installed on top of the resulting structure, such as placing the planar frame 111 on... Figure 11-7 The resulting structure; in Figure 11-9 In the process, the protective tape 109 on the bump 108 is removed, such as by light projection through a laser or ultraviolet (UV) light, or by etching such as anisotropic etching.

[0076] exist Figure 11-10 In this embodiment, the encapsulation is sawed (10-3), such as, but not limited to, by cutting with a blade, to obtain the corresponding encapsulation. In this embodiment, oxygen plasma treatment or aqueous solution treatment of lithium aluminum hydride can be performed on each surface at various steps as needed to enhance the bonding of the heterogeneous interface.

[0077] Figure 12 The mechanism of a silicon-based oxygen plasma processing technology is illustrated in [see...]. Figure 12The SiO2 film 112 is subjected to an oxygen plasma treatment process to activate the surface of the SiO2 film 112 to obtain a SiO2 film with an activated surface 112js, and then to obtain a SiO2 functional film with a surface 112gs having OH functional groups. In addition, Figure 13 The principle of the oxidation reaction based on the molding compound 103 is shown.

[0078] In the present application, a bridging agent is used as a linking agent to covalently bond the ink, the molding compound, the copper pillar and the silicon surface. Not only can a uniform and clear mark be formed between the ink and the silicon surface / molding compound, but it can also penetrate into the gaps between the various components of the package, such as the molding compound, the silicon surface and the copper pillar, so that the molding compound, the copper pillar and the silicon wafer are firmly and tightly bonded.

[0079] The features of several embodiments have been summarized above in order to provide a better understanding of aspects of the application. Those skilled in the art will readily understand that they can easily use the application as a basis for designing or modifying other processes and structures for implementing the same purposes and / or achieving the same advantages of the embodiments presented herein. Those skilled in the art will also realize that such equivalent constructions do not depart from the spirit and scope of the application, and that they can make various changes, substitutions and alterations thereto without departing from the spirit and scope of the application.

Claims

1. A package, characterized by Comprising: a silicon wafer; a molding compound surrounding the silicon wafer and embedding the silicon wafer therein; and a copper pillar disposed below the silicon wafer and embedded within the molding compound, wherein the silicon wafer has a first surface, and wherein the first surface has a first functional group bonded to a second functional group of a bridging agent, wherein the copper pillar has a surface with the first functional group, and the molding compound also has a surface with the first functional group, wherein both ends of the bridging agent have the second functional group, the second functional group of both ends of the bridging agent are bonded to the molding compound, the silicon wafer, and the copper pillar with covalent bonds, and wherein the second functional group of one end of the bridging agent is bonded to the first surface of the silicon wafer, and the second functional group of the other end of the same bridging agent is bonded to the surface of the molding compound or the surface of the copper pillar. The package further comprises a connector for joining with the first surface of the silicon wafer, wherein the surface of the connector has the first functional group, the joining of the silicon wafer with the connector is achieved by:

2. The package of claim 1, wherein, the bonding of the second functional group of the bridging agent to the first functional group of the surface of the connector and the first surface of the silicon wafer. The first functional group is an OH functional group.

3. The package of claim 1, wherein, The second functional group is a COOH functional group.

4. The package of claim 1, wherein, The bridging agent comprises glutaric acid.

5. The package of claim 1, wherein, The device having a surface with a first functional group comprises an ink.

6. The package of claim 3, wherein, All surfaces of the copper pillar and the molding compound have the first functional group.

7. The package of claim 1, wherein, Comprising:

8. A method of forming a package, characterized by, providing a molded wafer having a silicon surface, wherein a molding compound surrounds the molded wafer and embeds the molded wafer, and a copper pillar is disposed below the molded wafer and embedded within the molding compound; surface treating the molded wafer to have the silicon surface with a first functional group, wherein the copper pillar has a surface with the first functional group, and the molding compound also has a surface with the first functional group; and placing the treated molded wafer in a solution containing a bridging agent, wherein the bridging agent has a second functional group bonded to the first functional group, and wherein both ends of the bridging agent have the second functional group, the second functional group of both ends of the bridging agent are bonded to the molding compound, the molded wafer, and the copper pillar with covalent bonds, and wherein the second functional group of one end of the bridging agent is bonded to the first surface of the molded wafer, and the second functional group of the other end of the same bridging agent is bonded to the surface of the molding compound or the surface of the copper pillar. ​

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