Modified substrate and method for manufacturing the same

Abstract

To develop better substrate (e.g., glass substrates, glass-ceramic substrates, or silicon substrates) metallization techniques and materials that assist in substrate metallization. [Solution] The present invention provides a modified substrate comprising a substrate, a polyimide layer disposed on at least one of the surfaces of the substrate, and a patterned conductive material, wherein the patterned conductive material is disposed on the polyimide layer. The polyimide layer improves the adhesion of the conductive material to the substrate. The present invention also provides a method for manufacturing a modified substrate, comprising heating the substrate at a temperature of about 150°C to about 350°C to cure a polyimide precursor into polyimide to obtain a modified substrate. The present invention further provides the use of the modified substrate as a glass intermediate layer, a silicon intermediate layer, or an IC carrier.

Description

[Technical Field]

[0001] The present invention relates to a modified substrate and a method for manufacturing the same. [Background technology]

[0002] Glass and glass-ceramic materials possess characteristics such as low dielectric loss, high resistance, and resistance to bending. Therefore, when used in semiconductor packaging, glass and glass-ceramic substrates can offer advantages such as high frequency bandwidth density, high-density interconnection, and high data transfer speeds, significantly reducing energy loss during data transfer. This helps package more electronic components onto the same substrate. Furthermore, glass and glass-ceramic substrates also have potential applications in optical communications. Consequently, expectations for glass and glass-ceramic substrates have been rising in the semiconductor industry in recent years, and considerable effort is being put into research and development.

[0003] To achieve electrical connections with electronic components and / or external power supplies, through-glass vias (TGVs) can be formed in a glass substrate or a glass-ceramic substrate. For example, multiple through-holes penetrating the top and bottom surfaces of a glass substrate or glass-ceramic substrate can be formed by etching or laser processing, and then a conductive material (usually copper) is filled into the through-holes to form TGVs that electrically connect the top and bottom surfaces of the glass substrate or glass-ceramic substrate. Furthermore, various metal wiring designs can be mounted on the glass substrate or glass-ceramic substrate to obtain patterned conductive materials.

[0004] Glass metallization technology is one of the important processes in this field. One of the main areas of research in glass metallization technology is wet metal deposition. In wet metal deposition, metal oxides are used as adhesives, and the metal oxides are first applied to the main surface and walls of through-holes of the glass using a sol-gel method by wet coating, and then sintered to cure the adhesive; then the metal species layer is deposited by electroless plating, and the TGV and metal wiring are prepared by electroplating and patterning processes. The sintering temperature is at least approximately 300°C to 500°C, and the heat treatment is carried out for at least approximately 30 minutes. The thermal stress generated at this high temperature makes the glass susceptible to microcracks. Furthermore, the metal oxides currently used as adhesives are usually zinc oxide, tin oxide, or manganese oxide, which cannot be universally applied to different types of glass, and there are concerns regarding their stability. In particular, during subsequent metal patterning processes, when etching metal to form a desired circuit pattern, acidic etching solutions can easily corrode metal oxides, potentially negatively affecting adhesion between the exposed metal oxide and the subsequently applied build-up material (e.g., resin).

[0005] Silicon substrates, commonly used in semiconductor technology, can also be employed, and through-silicon vias (TSVs) can be formed on the silicon substrate. For example, multiple through-holes penetrating the top and bottom surfaces of the silicon substrate can be formed by etching or laser processing, and then a conductive material (usually copper) is filled into the through-holes to form TSVs that electrically connect the top and bottom surfaces of the silicon substrate. Furthermore, various metal wiring designs can be further implemented on the silicon substrate to obtain patterned conductive materials. However, problems still exist regarding adhesion and stability between the silicon substrate and the conductive material. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In light of the technical problems described above, the development of better substrate (e.g., glass substrates, glass-ceramic substrates, or silicon substrates) metallization techniques and materials that assist in substrate metallization is expected. [Means for solving the problem]

[0007] The present invention provides a modified substrate and a method for manufacturing the same. Specifically, the present invention relates to a modified substrate comprising a substrate, a polyimide layer disposed on the surface of the substrate, and a patterned conductive material, wherein the patterned conductive material is disposed on the polyimide layer. The substrate is selected from the group consisting of glass substrates, glass ceramic substrates, and silicon substrates. Preferably, the polyimide layer comprises (i) a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or heterocyclic ring containing at least two -COOH groups, and a combination thereof, comprising diamine residues, and (ii)

[0008] [ka]

[0009] group (in the formula, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and m are as defined herein.

[0010] The present invention relates to a method for manufacturing a modified substrate, comprising the steps of: preparing a substrate selected from the group consisting of a glass substrate, a glass ceramic substrate, and a silicon substrate; and applying a polyimide precursor to at least one surface of the substrate, wherein the polyimide layer comprises (i) a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or heterocyclic ring containing at least two -COOH groups, and a combination thereof, comprising diamine residues, and (ii)

[0011] [ka]

[0012] Further relating to a method comprising an applying step including a base, and a heating step of heating at a temperature of about 150 °C to 350 °C to cure a polyimide precursor into a polyimide to obtain a modified substrate.

[0013] The present invention further relates to the use of a modified substrate as a glass interlayer (or glass interposer), a silicon interlayer (or silicon interposer), or an IC carrier.

[0014] In order to make the above objects, technical features, and advantages of the present invention more clearly understandable, detailed descriptions are shown below by several specific samples.

Brief Description of the Drawings

[0015] [Figure 1] It is a diagram showing a substrate modification structure according to an embodiment of the present invention. [Figure 2] It is a diagram showing a substrate modification method and a metallization process according to an embodiment of the present invention. [Figure 3] It is a schematic diagram of a peel strength test sample according to an embodiment of the present invention.

Modes for Carrying Out the Invention

[0016] In order to facilitate the understanding of the disclosure shown in this specification, several terms are defined below.

[0017] The term "about" refers to the tolerance regarding a specific value determined by those skilled in the art, which depends partly on the method of measuring or determining the value.

[0018] The term "alkyl" preferably refers to a saturated linear or branched hydrocarbon group having 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. Examples of embodiments include (but are not limited to) methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, and n-hexyl.

[0019] The term "alkenyl" refers to an unsaturated linear or branched hydrocarbon group having at least one carbon-carbon double bond, preferably 2 to 10 carbon atoms, more preferably 3 to 8 carbon atoms. Examples of embodiments include (but are not limited to) vinyl, allyl, methacrylic, isopropenyl, pentenyl, hexenyl, heptenyl, 1-propenyl, 2-butenyl, 2-methyl-2-butenyl, and their analogues.

[0020] The term "aryl" refers to aromatic ring systems having 6 to 14 carbon atoms, such as 6-carbon monocyclic, 10-carbon bicyclic, or 14-carbon tricyclic aromatic ring systems. Examples of aryl embodiments include, but are not limited to, phenyl, tolyl, naphthyl, fluorenyl, anthracyl, phenanthryl, and their analogues.

[0021] The term "heterocyclic group" refers to a saturated, partially saturated (e.g., named with prefixes such as dihydro, trihydro, tetrahydro, hexahydro, etc.), or unsaturated 3- to 14-membered cyclic group, preferably a 4- to 10-membered cyclic group, more preferably a 5- to 6-membered cyclic group, consisting of a carbon atom and at least one heteroatom selected from N, O, or S. Preferably, the group has 1 to 4 heteroatoms, more preferably 1 to 3 heteroatoms. Embodiments include 5 or 6-membered heterocyclic groups having 1 to 3 heteroatoms selected from N, O, or S. In the present invention, the heterocyclic group may be a monocyclic, bicyclic, or tricyclic ring system, which includes a fused ring (e.g., fused with another heterocyclic ring or another aromatic carbon ring to form a fused ring).

[0022] Each embodiment and example of the present invention disclosed herein can be individually combined with all other embodiments and examples of the present invention, encompassing all possible combinations.

[0023] The substrate, polyimide material, metallization process, application, and modified substrate are described below, respectively.

[0024] substrate The substrate of the present invention is selected from the group consisting of glass substrates, glass ceramic substrates, and silicon substrates. According to some embodiments, the substrate of the present invention is a glass substrate.

[0025] The main component of the glass is silicon dioxide. Other components, such as metals or metal oxides, may be included as needed. The proportion of each component is adjusted according to the desired properties (e.g., color or heat resistance). The type of glass is not limited. In some embodiments, the polyimide material of the present invention is suitable for any or most types of glass without special limitations.

[0026] Glass possesses advantages such as low dielectric constant, high resistance, bending resistance, and low cost, and can play a role in heat dissipation to a certain extent. Furthermore, due to its high light transmittance, glass is suitable for optical electronic components and has promising applications in optical communications.

[0027] Glass ceramics primarily contain glass, crystalline phase components, fluxing agents, and / or other additives, and can be prepared by simultaneously burning glass powder and ceramic powder. Glass ceramics possess the advantages of both glass and ceramic, and have advantages in thermal, chemical, optical, and electrical aspects. The type of glass ceramic is not limited in this invention.

[0028] A silicon substrate is a substrate prepared using silicon as the main material. In some embodiments, the silicon substrate may be a silicon wafer substrate or a silicon chip substrate. A silicon wafer is a base material for manufacturing semiconductor devices. Silicon wafers are usually prepared from high-purity silicon material and are in sheet form. Silicon wafers can be processed into silicon chips through steps such as cutting, grinding, polishing, and cleaning.

[0029] Generally, glass substrates, glass-ceramic substrates, and silicon substrates are in sheet form and have two main surfaces. According to some embodiments, glass substrates, glass-ceramic substrates, and silicon substrates have two main surfaces and multiple vias (e.g., through-glass vias (TGVs) or through-silicon vias (TSVs)). Each via is generally cylindrical (right or oblique). According to some embodiments, the glass substrates, glass-ceramic substrates, and silicon substrates of the present invention generally have a thickness of about 0.1 mm to 2 mm, for example, 0.1 mm, 0.2 mm, 0.3 mm, 0.5 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.5 mm, or 2 mm, but are not limited to these. The size of the through-holes in the glass substrates, glass-ceramic substrates, and silicon substrates can be adjusted depending on the application. In some embodiments, when a glass substrate, a glass-ceramic substrate, and a silicon substrate are used as a glass interlayer (or glass interposer) or a silicon interlayer (or silicon interposer), the vias of the glass substrate, glass-ceramic substrate, and silicon substrate have diameters of approximately 5 μm to 500 μm, for example, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 200 μm, 300 μm, 400 μm, or 500 μm, and generally have aspect ratios of approximately 30:1 to approximately 1:1, for example, 30:1, 25:1, 20:1, 15:1, 10:1, 5:1, 3:1, 2:1, or 1:1. In some embodiments, when glass substrates, glass-ceramic substrates, and silicon substrates are used to connect to an external power supply (for example, instead of or as an auxiliary to an IC carrier), vias in the glass substrates, glass-ceramic substrates, and silicon substrates may have larger diameters, for example, 100 μm to 500 μm (e.g., 100 μm, 200 μm, 300 μm, 400 μm, or 500 μm), but are not limited to these.

[0030] When glass substrates, glass-ceramic substrates, or silicon substrates are applied to semiconductor packages, metal circuits and build-up materials (organic materials or dielectric materials, such as Ajinomoto Build-Up Film (ABF) or polyimide) are often placed on the surface of the glass substrate, glass-ceramic substrate, or silicon substrate. However, generally, adhesion between the substrate material and the metal is not good. Methods to improve adhesion between the substrate and the metal include surface treatment of the substrate by using an adhesive. In some embodiments, in addition to high adhesion to the metal, a preferred adhesive needs to have good adhesion to the substrate and subsequent build-up materials. The present invention provides a polyimide material that can be used as an adhesive, which is described in detail below.

[0031] Polyimide materials The present invention provides a polyimide precursor composition that can be applied to the surface of a substrate, heated, and cured to form a polyimide layer. The polyimide material of the present invention can be used as an adhesive. In some embodiments, the adhesive is also called a modifier or adhesion promoter.

[0032] According to some embodiments of the present invention, the polyimide precursor composition has the structure of formula (I):

[0033] [ka]

[0034] (I) (in the formula, Each G is independently a tetravalent organic group; Each R x These are H, C1~C independently. 14 A group containing an alkyl or ethylenically unsaturated group; n is an integer between 1 and 200; Each P is independently a divalent organic group, and with respect to the total moles of all divalent organic groups P in the composition, about 1 mol% to about 20 mol% of the divalent organic groups P are diamine residues selected from a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or a heterocyclic ring containing at least two -COOH groups, and combinations thereof, and about 0.5 mol% to about 40 mol% of the divalent organic groups P are

[0035]

Chemical formula

[0036] (linear polysiloxane), and the remaining P groups may each independently be other divalent aromatic groups or divalent heterocyclic groups, R 1 and R 2 each is independently a C1-C4 alkylene group, R 3 、R 4 、R 5 、and R 6 each is independently H, C1-C4 alkyl, or phenyl, m is an integer greater than 0)<00​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ Selected from the group consisting of, In the formula, each X is independently H, a halogen, a C1-C4 perfluoroalkyl, or a C1-C4 alkyl, and each of A and B, in each instance, is independently a covalently bonded, unsubstituted or substituted with one or more groups selected from hydroxyl and C1-C4 alkyl, a C1-C4 perfluoroalkylene group, a C1-C4 oxyalkylene group, a silaniylene group, -O-, -S-, -C(O)-, -OC(O)-, -S(O)2-, -C(=O)O-(C1-C4 alkylene group)-OC(=O)-, -CONH-, a phenylene group, a diphenylene group, or

[0043] [ka]

[0044] Here, K is -O-, -S(O)2-, a C1-C4 alkylene group, or a C1-C4 perfluoroalkylene group.

[0045] According to a preferred embodiment of the present invention, G is

[0046] [ka]

[0047] Selected from the group consisting of, In the formula, each Z is independently H, methyl, trifluoromethyl, or halogen.

[0048] In order to achieve better adhesion to the substrate (e.g., glass substrate, glass ceramic substrate, or silicon substrate) and metal, according to a preferred embodiment of the present invention, G is

[0049] [ka]

[0050] It is selected from the group consisting of the following.

[0051] According to some embodiments of the present invention, each R x These are independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-hydroxypropylmethyl acrylate group, ethyl methacrylate group, ethyl acrylate group, acrylic group, methacrylate group, n-butenyl, isobutenyl, or

[0052] [ka]

[0053] It is selected from the group consisting of the following.

[0054] According to some embodiments of the present invention, each R x These are independently H, isopropyl, or n-butyl.

[0055] According to some embodiments of the present invention, n is an integer from 5 to 150, preferably from 9 to 100, and more preferably from 1 to 100, 100, 120, 150, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 120, 150, 180, or 200.

[0056] According to some embodiments of the present invention, the composition contains about 1 mol% to about 20 mol% (for example, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 12 mol%, 15 mol%, 16 mol%, 18 mol%, or 20 mol%, preferably 2 mol% to 16 mol%, more preferably 5 mol% to 12 mol%) of divalent organic groups P, relative to the total moles of all divalent organic groups P in the composition.

[0057] [ka]

[0058] The divalent organic group P is present in an amount of approximately 0.5 mol% to approximately 40 mol% (for example, 0.5 mol%, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 12 mol%, 15 mol%, 18 mol%, 20 mol%, 25 mol%, 30 mol%, 35 mol%, or 40 mol%, preferably 5 mol% to 35 mol%, more preferably 10 mol% to 30 mol%).

[0059] [ka]

[0060] That is the case.

[0061] According to some embodiments of the present invention, the remaining P groups may each independently be other divalent aromatic groups or divalent heterocyclic groups, which are, for example, preferably,

[0062] [ka]

[0063] And may be selected from the group consisting of combinations thereof. In the formula, each R9 is independently H, C1-C4 alkyl, C1-C4 perfluoroalkyl, C1-C4 alkoxy, halogen, -OH, -COOH, -NH2, or -SH; each a is independently an integer from 0 to 4; each b is independently an integer from 0 to 4; R 10 These are covalent bonds, or -O-, -S-, -CH2-, -S(O)2-,

[0064] [ka]

[0065] , -C(CF3)2-, -C(O)-, -C(CH3)2-, -CONH-,

[0066] [ka]

[0067] A base selected from the group consisting of, where each of c and d is independently an integer from 0 to 20; R9 and a are as described above, R 12 is -S(O)2-, covalent bond, C1-C4 alkylene group, or C1-C4 perfluoroalkylene group; The other divalent aromatic group or divalent heterocyclic group is preferably,

[0068] [ka] [ka]

[0069] And may be selected from the group consisting of combinations thereof. In the formula, each a is independently an integer between 0 and 4, and each Z is independently H, methyl, trifluoromethyl, or halogen; The other divalent aromatic group or divalent heterocyclic group is most preferably,

[0070] [ka]

[0071] The group may also be selected from the group consisting of combinations thereof.

[0072] Formula according to some embodiments of the present invention

[0073] [ka]

[0074] Regarding R 1 and R 2Each of these is independently a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group, an isobutylene group, or a tert-butylene group. According to a preferred embodiment of the present invention, R 1 and R 2 Each of these is a methylene group, an ethylene group, or an n-propylene group. According to a more preferred embodiment of the present invention, R 1 and R 2 Each of these is an n-propylene group.

[0075] According to some embodiments of the present invention, R 3 , R 4 , R 5 , and R 6 Each of these is independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, or phenyl. According to some preferred embodiments of the present invention, R 3 , R 4 , R 5 , and R 6 Each of them is methyl.

[0076] According to some embodiments of the present invention, m is a greater-than-zero integer, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 18, 20, 30, 40, 50, or 100. In preferred embodiments of the present invention, m is 1 or 2. According to more preferred embodiments of the present invention, m is 1.

[0077] According to some embodiments of the present invention, the polyimide layer has the structure of formula (II):

[0078] [ka]

[0079] (In the formula, G, P, and n are defined as above.) It has repeating units.

[0080] The polyimide of the present invention is a random copolymer rather than a block copolymer; that is, the divalent organic group P is randomly distributed within the polyimide, and therefore the polymerization process is simple.

[0081] Generally, polyimides do not exhibit good adhesion to glass and metals, and even if polyimides show adhesion to only one of them, they are still insufficient to achieve the objective of glass metallization. However, the inventors of the present invention have conducted experimental studies to provide a polyimide material that exhibits excellent adhesion to both glass and metals. The polyimide material of the present invention is suitable as an adhesive for glass metallization and is applicable to various glass substrates. Furthermore, the inventors of the present invention have also found that the polyimide material of the present invention exhibits excellent adhesion to glass ceramic substrates, silicon substrates, and metals, and as a result, the polyimide material is also suitable for the metallization of glass ceramic substrates and silicon substrates. Without being bound by theory, this is thought to be due to a specific divalent organic group P in the polyimide material. For example, a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms or carboxyl (-COOH) in the divalent organic group P has an affinity for metal ions, and nitrogen atoms and carboxylate (-COOH) - It can act as an electron donor to electron-deficient metal ions through its lone pairs of electrons. Furthermore, the linear polysiloxane contained in the divalent organic group P has an affinity for glass, glass ceramics, or silicon, which is due to the structural similarity between the polysiloxane structure and the above materials. For example, when heated, it can form hydrogen bonds or chemical bonds with glass.

[0082] The polyimide precursor composition of the present invention further comprises a solvent capable of improving the leveling properties of the composition. The solvent may be any suitable solvent known to those skilled in the art, and the solvent content is not particularly limited as long as it facilitates the coating of the composition.

[0083] According to some embodiments of the present invention, the content of the oligomer having the structure of formula (I) is about 0.1 wt% to about 20 wt%, preferably about 1 wt% to about 5 wt%, relative to the total mass of the total polyimide precursor composition.

[0084] The polyimide precursor composition of the present invention may contain other optional materials known in formulation technology, such as antioxidants, hindered amine light stabilizers, UV light absorbers, and stabilizers, surfactants, initiators, catalysts, flow control agents, thixotropic agents, fillers, antifungal agents, and other conventional additives. The polyimide precursor composition of the present invention has good adhesion to substrates (e.g., glass substrates, glass ceramic substrates, or silicon substrates), metals, and dielectric materials without the addition of adhesion promoters.

[0085] The polyimide precursor composition of the present invention may optionally contain a catalyst to achieve a low-temperature curing effect by curing the polyimide at a lower curing temperature. According to some embodiments of the present invention, the catalyst is an amine, for example, a tertiary amine, a nitrogen-containing heterocyclic ring, or a nitrogen-containing heteroaryl. Specific embodiments include triethylamine,

[0086] [ka]

[0087] These are some examples.

[0088] The present invention further provides polyimides prepared from polyimide precursor compositions. The polyimides of the present invention can be obtained by wet coating a glass or other substrate with the polyimide precursor composition, heating, and cyclizing the polyimide precursor composition. Wet coating can be carried out by any method known in the art, such as immersion / dip coating, spray coating, spin coating, flow coating, etc. The polyimides of the present invention are thermosetting polyimides.

[0089] The polyimide precursor (oligomer having the structure of formula (I)) of the present invention has low viscosity and good handling properties due to its low molecular weight. The viscosity of the polyimide precursor composition of the present invention can only reach 1 cp to 10 cp (e.g., 5 cp), and the polyimide precursor composition can penetrate glass through-holes or silicon through-holes by capillary action to form a thin layer, which is then cured to form a polyimide layer. In other words, the polyimide layer can be arranged on the walls of multiple through-holes.

[0090] According to some embodiments of the present invention, the curing temperature of the polyimide precursor is 150°C to 350°C, for example, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 300°C, or 350°C. According to some preferred embodiments, the polyimide precursor may be cured at a temperature of 150°C to 250°C to achieve the purpose of low-temperature curing. According to some embodiments of the present invention, the curing time of the polyimide precursor is 15 minutes to 200 minutes, for example, 15 minutes, 30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, or 200 minutes. The heating step of the present invention may be carried out in a single step, two steps, or multiple steps. For example, in the first step, heating may be carried out at a lower temperature (e.g., 80°C or 90°C) and for a shorter duration (e.g., 5 minutes or 10 minutes) to remove the solvent, and then in the second step, curing may be carried out at a higher temperature (e.g., 150°C) and for a longer duration (e.g., 1 hour). If necessary, in the third step, curing may be carried out at a much higher temperature (e.g., 250°C or 350°C) and for a longer duration (e.g., 2 hours).

[0091] According to some embodiments of the present invention, the polyimide film formed from the polyimide precursor has a thickness of about 0.05 μm to about 20 μm, preferably about 0.1 μm to about 10 μm, after curing, for example, 0.1 μm, 0.2 μm, 0.3 μm, 0.5 μm, 1 μm, 1.5 μm, 2 μm, 5 μm, or 10 μm.

[0092] According to some embodiments of the present invention, the polyimide of the present invention has a glass transition temperature (T) of about 150°C to 300°C, for example, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, or 300°C. g Conventional polyimides have a temperature of 300°C or higher. g While possessing the properties of the present invention, the polyimide of this invention has a lower T than conventional polyimides. g It has. Therefore, there is a heating step in the subsequent process, and the temperature of the polyimide of the present invention is T g If it exceeds this value, the fluidity of the polyimide can be improved, which promotes tighter alignment / contact between the polyimide and its adjacent layers.

[0093] According to a preferred embodiment of the modified substrate of the present invention, the substrate has two main surfaces and a plurality of through-holes, and the polyimide layer is disposed on at least one of the main surfaces of the substrate and on the walls of each through-hole. Figure 1 shows a modified substrate according to an embodiment of the present invention. As shown in Figure 1, the substrate 11 has two main surfaces and a plurality of through-holes 11h. The polyimide layer 12 is disposed on each of the main surfaces of the substrate 11 and on the walls of each through-hole.

[0094] Metallization process Since polyimide is an insulator, metal layers or metal circuits cannot be directly fabricated on its surface. In this industry, it is known to metallize polyimide by making the surface conductive using sputtering or electroless plating (sometimes described as forming a tie coating layer or seed layer on the surface, which is generally only a few nanometers to tens of nanometers thick), and then performing electroplating. Regarding a method for making the surface of polyimide conductive by electroless plating, the method specifically includes cleaning and roughening the surface of the polyimide layer with a detergent, then activating the surface of the polyimide layer with a surfactant containing metal ions, or cleaning and activating the surface of the polyimide layer with a composition containing a detergent and a surfactant; then reducing the metal ions attached to the surface of the polyimide substrate to a metal catalyst using a reducing agent; and finally, preparing a metal layer by performing electroless plating and / or electroplating on the surface of the polyimide.

[0095] The cleaning agent may be an alkaline compound, for example, potassium hydroxide, sodium hydroxide, calcium hydroxide, or lithium hydroxide (but is not limited to these), preferably containing at least one of potassium hydroxide, sodium hydroxide, calcium hydroxide, and lithium hydroxide. The surfactant containing a metal ion may be a sulfate, nitrite, diamine nitrite, chloride, or dichlorodiamine salt of the metal ion (but is not limited to these), and the metal ion may be a palladium ion, nickel ion, chromium ion, titanium ion, or copper ion (but is not limited to these), preferably containing at least one of palladium ions, nickel ions, chromium ions, titanium ions, and copper ions. The reducing agent may be hydrogen boride (e.g., sodium borohydride or potassium borohydride), amidoborane (e.g., diamidoborane, trimethylamineborane, or triethylamineborane), hydrazine hydrate, hypophosphorous acid, or a salt thereof (e.g., sodium hypophosphite or potassium hypophosphite) (but is not limited to these).

[0096] In the present invention, the metal circuit may be manufactured by any known and suitable metallization process. According to some embodiments of the present invention, a nickel layer is plated onto the surface of the polyimide by electroless plating to serve as a seed layer, and then a copper layer is plated onto the nickel surface by electroplating. The polyimide of the present invention has good adhesion to metal without the need for adhesion promoters as additives and without the need for heating / sintering after plating the metal onto the surface of the polyimide. According to some embodiments of the present invention, the peel strength of the polyimide and metal layer can reach 400 gf / cm or more, for example, 400 gf / cm, 500 gf / cm, 600 gf / cm, 700 gf / cm, 800 gf / cm, 900 gf / cm, 1,000 gf / cm, 1,100 gf / cm, 1,200 gf / cm, 1,300 gf / cm, 1,400 gf / cm, or 1,500 gf / cm, preferably 600 gf / cm or more.

[0097] According to some embodiments of the present invention, a plated metal layer is filled into through-holes in a glass substrate or a glass-ceramic substrate to form a TGV, or into through-holes in a silicon substrate to form a TSV. The diameter of the TGV or TSV mainly depends on the diameter of the through-hole in the glass substrate, glass-ceramic substrate, or silicon substrate, and the thickness of the polyimide layer placed on the wall of the through-hole.

[0098] The plated metal layer is patterned to form a desired circuit pattern. Acidic etching solutions are commonly used in the patterning process. The polyimide of the present invention is acid-resistant, so that only the metal layer (and seed layer) can be etched by the acidic etching solution. In contrast, in the conventional wet metal deposition process, a metal oxide is used as an adhesive. The metal oxide is also susceptible to corrosion by the acidic etching solution, except for the metal layer, resulting in insufficient stability.

[0099] Applicable In some embodiments, the modified substrate of the present invention can be applied to industries such as micro-LEDs, semiconductor packages (e.g., 2.5D and 3D packages), IC carriers, micro-electromechanical systems (MEMS), biochips, and 5G chips. Taking semiconductor packages as an example, a glass or glass-ceramic substrate may be used as the glass interlayer (or glass interposer), or a silicon substrate may be used as the silicon interlayer (or silicon interposer).

[0100] In some embodiments, a redispersion layer (RDL) may be placed on the top, bottom, or both surfaces of the substrate to improve the flexibility of IC design and to form electrical connections to chips, IC carriers, and / or printed circuit boards (PCBs). The RDL includes a patterned metal layer (circuit layer) and an organic insulating layer (dielectric layer). In some embodiments, the organic insulating layer may be a build-up material, which is an organic dielectric material used to protect metal wires, provide dielectric properties, reduce dielectric loss, and regulate warping due to thermal stress. Currently, organic insulating layer materials used in the industry are Ajinomoto Build-Up Film (ABF) or polyimide. The polyimide of the present invention has at least the technical feature that, because both the polyimide and the organic insulating layer material are organic resins and have high compatibility, the polyimide exposed after the metal layer has been patterned has good adhesion when in direct contact with the subsequently placed organic insulating layer. In contrast, the prior art wet metal deposition process uses metal oxides as adhesives, which have poor adhesion to the organic insulating layer material and are at risk of easily separating.

[0101] Figure 2 shows a substrate modification method and metallization process according to an embodiment of the present invention. As shown in Figure 2, a substrate 21 was prepared. Multiple through-holes 21h penetrating through the upper and lower surfaces of the substrate 21 were formed by etching, laser treatment, or a combination thereof. Next, a polyimide precursor composition was applied to the upper and lower surfaces of the substrate 21 and to the walls of the through-holes, and subsequently, a polyimide layer 22 was formed by thermal curing. Then, a seed layer (not shown) was formed on the surface of the polyimide layer 22 by sputtering, electroless plating, etc., and a conductive material (usually copper) was applied to form a conductive layer 23 that fills the through-holes 21h, thereby forming vias. Next, the conductive layer 23 was patterned to form a metal circuit, exposing a portion of the polyimide layer 22. Next, an organic insulating layer 24 was applied and patterned (or planarized) to form a redispersed layer R. The steps may be repeated several times to allow the redispersed layer to contain more patterned conductive layers 23 and organic insulating layers 24.

[0102] Furthermore, in some embodiments of the present invention, the polyimide of the present invention has a relatively low T g Because it has a heating step in the subsequent process, the heating temperature is the T of the polyimide of the present invention g If the value exceeds a certain threshold, the fluidity of the polyimide can be enhanced, which promotes tighter alignment / contact between the polyimide and the organic insulating layer.

[0103] The modified substrate of the present invention can be used not only in applications requiring fine metal wiring, such as glass interlayers (or glass interposers) or silicon interlayers (or silicon interposers), but also in applications with lower requirements regarding the fineness of the metal wiring, such as IC carriers. The IC carrier material typically includes bismaleimidotriazine (BT) resin as the core layer, Ajinomoto build-up film (ABF) as the build-up material, and metal wires. The IC carrier is electrically connected to larger external metal balls. The modified substrate of the present invention can replace bismaleimidotriazine (BT) resin as the core layer of the IC carrier, serving as a more advanced alternative and exhibiting a wide range of effects such as stability and low power transmission loss.

[0104] Modified substrate In summary, the modified substrate of the present invention comprises a substrate selected from the group consisting of a glass substrate, a glass ceramic substrate, and a silicon substrate; a polyimide layer disposed on at least one surface of the substrate; and a conductive material disposed on the polyimide layer. The conductive material may be a patterned conductive material. The modified substrate may further include an organic insulating layer and a redispersed layer formed by the patterned conductive material and the organic insulating layer.

[0105] According to some embodiments, the substrate of the present invention is a glass substrate having a plurality of through holes. According to some embodiments, a polyimide layer is further disposed on the walls of the plurality of through holes.

[0106] According to some embodiments, the peel strength between the polyimide layer of the present invention and the substrate (e.g., a glass substrate, a glass-ceramic substrate, or a silicon substrate) can reach 550 gf / cm or more, and the peel strength between the polyimide layer and the conductive material layer can reach 400 gf / cm or more. [Examples]

[0107] The following examples are provided to further illustrate the present invention and are not intended to limit the scope of the invention. Any modifications and changes that can be easily realized by those skilled in the art are included within the scope of this disclosure and the claims appended herein.

[0108] The abbreviations used in the following examples are defined as follows: <dianhydride> A-1: 3,3',4,4'-biphenyltetracarboxylic acid dianhydride; A-2: 1,2,4,5-benzenetetracarboxylic anhydride; A-3: 4,4'-(hexafluoroisopropylidene)diphthalic anhydride; A-4: 4,4'-oxydiphthalic anhydride; A-5: 3,3',4,4'-benzophenonetetracarboxylic dianhydride; <Diamine> <Diamines having other aromatic groups or heterocyclic groups> D-1: p-phenylenediamine; D-2: 4,4'-diamino-2,2'-dimethylbiphenyl; D-3: 4,4'-diaminodiphenyl ether; D-4: 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl; D-5: 1,3-bis(4-aminophenoxy)benzene; D-6: 1,4-bis(4-aminophenoxy)benzene; D-7: 1,3-bis(3-aminophenoxy)benzene; D-8: 2,2-bis[4-(4-aminophenoxy)phenyl]propane; <Diamines having linear polysiloxanes and comparative diamines having similar linear structures> D-9: 1,3-bis(3-aminopropyl)tetramethyldisiloxane; D-10: Bis(3-aminopropyl)-terminated poly(dimethylsiloxane), Mn: approximately 2500; D-11: Bis(3-aminopropyl)-terminated poly(dimethylsiloxane), Mn: approximately 27,000; D-12: Bis(3-aminopropyl)-terminated poly(ethylene glycol), Mn: approximately 1500; D-13: 4,7,10-trioxa-1,13-tridecanediamine; <Diamines having a nitrogen-containing heteroaromatic ring or at least two -COOH groups> D-14: 5,5'-Methylenebis(2-aminobenzoic acid); D-15: [2,2'-bipyridine]-5,5'-diamine; D-16: [2,2'-bipyrimidine]-5,5'-diamine; D-17: 3,5-diamino-1,2,4-triazole; <Catalyst> C-1: Triethylamine; C-2: Pyridine; C-3: Imidazole; C-4: Piperidine; and C-5: Monoethanolamine.

[0109] Preparation of amidic acid / amidic acid ester oligomers (Examples 1-44 and Comparative Examples 1-28): The dianhydride was weighed according to the amounts shown in Tables 1-3, then poured into a reactor, 2000 g of NMP solvent was added, and the mixture was stirred. The diamine monomer was added at room temperature and stirred for 1 hour, then the temperature was raised to 50°C and heated for 8 hours. The temperature was then lowered to room temperature and collected. Solvent was added as needed. The amide acid / amide acid ester oligomer glue solution was adjusted to obtain a solid content of 20 wt%.

[0110] (Examples 45-57): Amidomic acid / amidomic acid ester oligomers were synthesized in the same manner as described above. However, after lowering the temperature to room temperature, a specified mass percentage of catalyst (relative to the mass of the amidomic acid / amidomic acid ester oligomer) was added, the mixture was stirred for 2 hours, and then collected. The subsequent curing temperature (see hard baking temperature in Table 4) decreased due to the addition of the catalyst.

[0111] (Examples 58-66): Compared to Examples 45-57, no catalyst was added, but a lower subsequent curing temperature was still maintained, similar to that of Examples 45-57.

[0112] Test of peel strength (adhesion) between polyimide and glass. As shown in the schematic diagram of Figure 3, a 20cm × 20cm Corning EXG (thickness 0.7mm) glass substrate 31 was used. A 20cm × 1.5cm PI adhesive tape 32 was attached to the right side of the upper surface of the glass substrate 31. The glass substrate 31 and the PI adhesive tape 32 were coated with the amide acid / amide acid ester oligomer glue solutions of the examples and comparative examples by spin coating. Then, soft baking (90°C / 10 min) and hard baking (two stages: 150°C / 1 hour + 350°C / 2 hours, or 150°C / 1 hour + 250°C / 2 hours) (depending on the example) were performed to prepare a 10μm thick polyimide film. The sample subjected to hard baking was cut into a 20cm × 1cm test strip along the cut line 33 using a blade. The PI adhesive tape surface of the test strip was separated from the glass. The polyimide film on the PI adhesive tape surface was pulled. The tensile strength of the stretched polyimide film was tested and recorded using an Instron 3342 tensile machine. If the peel strength exceeded 550 gf / cm, the polyimide film was considered to have passed the test. If the polyimide film failed the test, subsequent peel strength (adhesion) tests between the polyimide and the metal were not performed.

[0113] Testing the peel strength (adhesion) between polyimide and metal. The amide acid / amide acid ester oligomer glue solutions of the examples and comparative examples were coated onto a 20cm × 20cm Corning EXG (0.7mm thick) glass substrate by spin coating. The PI coating thickness was 1 μm. Soft baking was performed at 80°C for less than 5 minutes. Then, hard baking was performed at temperatures of 150°C for 1 hour + 350°C for 2 hours, or 150°C for 1 hour + 250°C for 2 hours (depending on the sample). After hard baking, the treated samples were immersed in an aqueous solution containing 1.5 g / L sodium hydroxide and 0.5 g / L palladium sulfate at 50°C for 10 minutes, washed with pure water, and then treated with 1M DiaminoBorane. (aq) The material was immersed in an aqueous (NH2-BH-NH2) solution at 25°C for 10 minutes, then washed with pure water and dried. Electroless nickel plating was performed (NPR-18 (prepared by C. Uyemura & Co., Ltd.), 45°C, 3 minutes), and copper was electroplated to a thickness of 18 μm (electroplating solution: 70 g / L copper sulfate, 200 g / L sulfuric acid, 50 mg / L chloride ions, and 5 mL / L electroplating additive (LUCINA SF-M, OKUNO Chemical Industries Co., Ltd.); electroplating temperature: 25°C; cathode current density: 3 A / dm²). 2 ) reached.

[0114] The sample was cut into 20cm x 1cm test strips. The polyimide layer was slightly separated from the copper plating layer at the end of the test strip. The peel strength was tested using an Instron 3342 tensile strength machine. A peel strength of over 400 gf / cm was considered acceptable.

[0115] The hard baking temperature in the second stage and the test results for each example and comparative example are reported in Tables 1 to 4.

[0116] [Table 1A]

[0117] Table 1B

[0118]

Table 1C

[0119] Table 2A

[0120] Table 2B

[0121] Table 3A

[0122] Table 3B

[0123]

Table 3C

[0124]

Table 3D

[0125] Table 4A

[0126] Table 4B

[0127] Table 4C

[0128] As shown in Tables 1-4, the polyimide of the present invention comprises a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or heterocyclic ring containing at least two -COOH groups, and a combination thereof, selected from diamine residues, and

[0129] [ka]

[0130] The compound contains a group that, as a result, can achieve a peel strength of 550 gf / cm or more between polyimide and glass, and a peel strength of 400 gf / cm or more between polyimide and metal.

[0131] Furthermore, the polyimides of Examples 58 and 61 were selected to test the effect of different glasses on tensile strength, as shown in Table 5.

[0132] [Table 5]

[0133] The results show that the polyimide of the present invention cannot be separated from the glass due to a peel strength of more than 1600 gf / cm between the polyimide and the glass, and satisfies the requirement of a peel strength of more than 400 gf / cm between the polyimide and the metal, making it suitable for various glass substrates. [Explanation of symbols]

[0134] 11, 21, 31 circuit boards 11th and 21st holes (through-hole) 12, 22 Polyimide layer 23 Conductive layer 24 Organic insulating layer 32 Adhesive Tape 33 Cut Lines R redistribution layer

Claims

1. A substrate selected from the group consisting of glass substrates, glass ceramic substrates, and silicon substrates. A polyimide layer disposed on at least one surface of the substrate, and Patterned conductive material arranged in a polyimide layer A modified substrate containing the above.

2. The modified substrate according to claim 1, wherein the substrate is a glass substrate and has a plurality of through holes.

3. The modified substrate according to claim 2, wherein a polyimide layer is further disposed on the walls of a plurality of through-holes.

4. The polyimide layer comprises (i) a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or heterocyclic ring containing at least two -COOH groups, and a combination thereof, selected from diamine residues, and (ii) 【Chemistry 1】 base (In the formula, R 1 and R 2 Each of them independently, C 1 ~C 4 It is an alkylene group, R 3 、R 4 、R 5 、and R 6 each of which is independently H, C 1 ~C 4 alkyl, or phenyl, (m is a non-zero integer) A modified substrate according to claim 1, comprising:

5. The polyimide layer has the structure of formula (II): 【Chemistry 2】 (In the formula, Each G is independently a tetravalent organic group. n is an integer between 1 and 200. Each P is independently a divalent organic group, and approximately 1 mol% to approximately 20 mol% of the total moles of all divalent organic groups P in the polyimide layer are diamine residues selected from nitrogen-containing heteroaromatic rings containing at least two nitrogen atoms, aromatic or heterocyclic rings containing at least two -COOH groups, and combinations thereof, and approximately 0.5 mol% to approximately 40 mol% of the divalent organic groups P are 【Transformation 3】 And, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and m have the definitions set forth in claim 4. A modified substrate according to claim 4, having repeating units having

6. R 1 and R 2 Each of these is an n-propylene group, R 3 , R 4 , R 5 , and R 6 Each of them is independently methyl, The modified substrate according to claim 5, wherein m is 1.

7. The diamine residue, 【Chemistry 4】 A modified substrate according to claim 4, selected from and combinations thereof.

8. A method for manufacturing a modified substrate, A step of preparing a substrate, selected from the group consisting of glass substrates, glass ceramic substrates, and silicon substrates, A step of applying a polyimide precursor to at least one surface of a substrate, wherein the polyimide layer comprises (i) a nitrogen-containing heteroaromatic ring containing at least two nitrogen atoms, an aromatic ring or heterocyclic ring containing at least two -COOH groups, and a combination thereof, selected from diamine residues, and (ii) 【Transformation 5】 base (In the formula, R 1 and R 2 Each of them independently, C 1 ~C 4 It is alkyl, R 3 , R 4 , R 5 , and R 6 Each of these is independently H, C 1 ~C 4 Alkyl or phenyl, (m is a non-zero integer) Processes including, The process involves heating the polyimide precursor to a polyimide layer at a temperature of approximately 150°C to 350°C. Methods that include...

9. The method according to claim 8, further comprising the step of applying a patterned conductive material to the surface of a polyimide layer, wherein the peel strength between the polyimide layer and the substrate is 550 gf / cm or more, and the peel strength between the polyimide layer and the conductive material is 400 gf / cm or more.

10. A method for using the modified substrate described in claim 1 as a glass intermediate layer, a silicon intermediate layer, or an IC carrier.

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