Method for manufacturing semiconductor device

Abstract

A method for manufacturing a semiconductor device (semiconductor chip laminate) comprising: irradiating at least one of a first insulating resin film of a first semiconductor member and a second insulating resin film of a second semiconductor member with ultraviolet rays; and bonding the first semiconductor member and the second semiconductor member by hybrid bonding in which the first insulating resin film and the second insulating resin film are bonded. The present invention makes it possible to satisfactorily join insulating resin films to each other even at a low temperature of about 200°C.

Description

Method for manufacturing semiconductor device

[0001] The present disclosure relates to a method for manufacturing a semiconductor device.

[0002] As a three-dimensional integration technology for semiconductor chips, hybrid bonding technology is sometimes applied, which bonds electrodes together and also bonds the insulating films around the electrodes together. While silica films are often used as insulating films for hybrid bonding, the use of insulating resin films formed from photosensitive resins is also being considered (see, for example, Patent Document 1). Because insulating resin films are less susceptible to the effects of foreign matter than silica films, the use of insulating resin films is expected to improve yield.

[0003] JP 2012-069585 A

[0004] The present invention relates to a method for bonding insulating resin films together by heating at a lower temperature when manufacturing a semiconductor device by hybrid bonding including bonding insulating resin films together.

[0005] The present disclosure includes the following: [1] A method for manufacturing a semiconductor device, comprising: preparing a first semiconductor member having a first semiconductor substrate and a first bonding layer provided on the first semiconductor substrate, the first bonding layer including a first electrode and a first insulating resin film, the first insulating resin film having an opening in which the first electrode is provided, preparing a second semiconductor member having a second semiconductor substrate and a second bonding layer provided on the second semiconductor substrate, the second bonding layer including a second electrode and a second insulating resin film, the second insulating resin film having an opening in which the second electrode is provided, irradiating at least one of the first insulating resin film or the second insulating resin film with ultraviolet light, and bonding the first semiconductor member and the second semiconductor member by hybrid bonding in which the first electrode is bonded to the second electrode and the first insulating resin film is bonded to the second insulating resin film. [2] The method according to [1], wherein bonding the first semiconductor member and the second semiconductor member comprises pressing the first semiconductor member and the second semiconductor member while heating them to a temperature of 180°C or higher and 250°C or lower, thereby bonding the first insulating resin film and the second insulating resin film. [3] The method according to [1] or [2], wherein the first semiconductor substrate is a semiconductor wafer, the second semiconductor substrate is a semiconductor chip, and one first semiconductor member is bonded to a plurality of second semiconductor members, and the method further comprises dividing the first semiconductor member bonded to the second semiconductor member, thereby forming a semiconductor chip stack including the first semiconductor member and the second semiconductor member, with the first semiconductor substrate singulated into semiconductor chips. [4] The method according to any one of [1] to [3], wherein the first insulating resin film and the second insulating resin film contain a resin containing an imide group. [5] The method according to [4], wherein the resin containing an imide group is a polyimide resin, a polyamideimide resin, a bismaleimide resin, or a combination thereof. [6] The method according to [4], wherein the resin containing an imide group is a resin having a structural unit containing an imide group and a polysiloxane bonded to the structural unit. [7] The method according to any one of [1] to [3], wherein the first insulating resin film and the second insulating resin film contain a polybenzoxazole resin.[8] The method according to any one of [1] to [3], wherein the first insulating resin film and the second insulating resin film contain a benzocyclobutene resin.

[0006] When manufacturing a semiconductor device by hybrid bonding, which includes bonding insulating resin films together, the insulating resin films can be bonded together by heating at a lower temperature. By bonding insulating resin films together by heating at a lower temperature, damage to the semiconductor component due to high heat can be easily avoided. Furthermore, outgassing from the insulating resin film can also be suppressed.

[0007] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, and are not intended to be limiting unless otherwise specified.

[0008] The present invention is not limited to the following examples.

[0009] 1, 2, and 3 are process diagrams showing an example of a method for manufacturing a semiconductor device by the method according to the present disclosure. The method shown in Figures 1 to 3 includes: preparing a first semiconductor member 10 having a first semiconductor substrate 11 and a first bonding layer 15 provided on the first semiconductor substrate 11, the first bonding layer 15 including a first electrode 12 and a first insulating resin film 13; preparing a second semiconductor member 20 having a second semiconductor substrate 21 and a second bonding layer 25 provided on the second semiconductor substrate 21, the second bonding layer 25 including a second electrode 22 and a second insulating resin film 23; irradiating ultraviolet light UV onto at least one of the first insulating resin film 13 or the second insulating resin film 23; and bonding the first semiconductor member 10 and the second semiconductor member 20 by hybrid bonding.

[0010] 1 to 3, a first semiconductor member 10 having a first semiconductor substrate 11, which is a semiconductor wafer, and a second semiconductor member 20 having a second semiconductor substrate 21, which is a semiconductor chip, are joined by hybrid bonding. Multiple second semiconductor members 20 are joined to one first semiconductor member 10, and then the first semiconductor member 10 joined to the second semiconductor member 20 is divided. As a result, a semiconductor chip stack 30 (semiconductor device) is formed, which has the first semiconductor member 10 and the second semiconductor member 20 separated into semiconductor chips. However, the combination of the first semiconductor member and the second semiconductor member to be joined is not limited to this and can be changed as appropriate.

[0011] Preparing the second semiconductor member 20 includes, for example, providing a plurality of second electrodes 22 on one main surface of the second semiconductor substrate 21 as shown in (a) of FIG. 1, providing a second insulating resin film 23 that covers the second electrodes 22 as shown in (b) of FIG. 1, removing a portion of the second insulating resin film 23 from the side opposite the second semiconductor substrate 21 to form an opening 23a that exposes the second electrode 22 as shown in (c) of FIG. 1, and dividing the second semiconductor substrate 21 and the second insulating resin film 23 as shown in (d) of FIG. 2, thereby forming the second semiconductor member 20 having the second semiconductor substrate 21, the second electrodes 22, and the second insulating resin film 23, which are individual semiconductor chips.

[0012] The second semiconductor substrate 21 before being singulated into semiconductor chips may be a semiconductor wafer. The diameter of the semiconductor wafer (second semiconductor substrate) may be, for example, 150 mm or more and 300 mm or less. The thickness of the semiconductor wafer (second semiconductor substrate) may be, for example, 40 μm or more and 1000 μm or less.

[0013] The second electrode 22 may be a conductor containing, for example, copper. The width (maximum width) of the second electrode 22 may be, for example, 1 μm or more and 13 μm or less. The height of the second electrode 22 may be, for example, 1 μm or more and 90 μm or less. A through electrode that penetrates the second semiconductor substrate 21 may be provided. The second electrode 22 can be formed by a conventional method using plating or the like.

[0014] The second insulating resin film 23 may be a film containing, for example, a resin containing an imide group, a polybenzoxazole resin, a benzocyclobutene resin, or a combination thereof. The first insulating resin film 13 may also be a film containing, for example, a resin containing an imide group, a polybenzoxazole resin, a benzocyclobutene resin, or a combination thereof.

[0015] The resin containing an imide group that constitutes the first insulating resin film 13 and the second insulating resin film 23 may be a polyimide resin, a polyamideimide resin, or a bismaleimide resin. The polyimide resin may be, for example, a polymer containing a structural unit (imide unit) represented by the following formula (1A). The polyamideimide resin may be a polymer containing a structural unit (imide unit) represented by the following formula (1B) or (1C). Alternatively, the resin containing an imide group may be a resin having an imide unit represented by formula (1A), (1B), or (1C) and a linear, branched, or cage-shaped polysiloxane bonded to the imide unit.

[0016]

[0017] In formulas (1A) to (1C), R １ represents a tetravalent organic group, and R ２ represents a trivalent organic group, and R １０ teeth ２ represents a 2-valent organic group, and * represents a bond.

[0018] R １ can be a group containing an aromatic group, for example, R １ may be a group obtained by removing four hydrogen atoms from a compound represented by the following formula (11), (12), or (13): ２ can be a group containing an aromatic group, for example, R ２ Alternatively, it may be a group obtained by removing three hydrogen atoms from a compound represented by the following formula (11), (12), or (13): In formula (13), X represents a direct bond, a methanediyl group, a propane-2,2-diyl group, a 1,1,1,3,3,3-hexafluoropropane-2,2-diyl group, a carbonyl group, a sulfonyl group, a thio group, a carbonyloxy group, an oxy group, a fluorene-9,9-diyl group, or an amide group.

[0019]

[0020] R in formulas (1A) to (1C) １０ may be an optionally substituted alkylene group, a group containing an optionally substituted aromatic group, a group containing an optionally substituted cycloaliphatic group, or a group containing a combination thereof. The aromatic group may be a group obtained by removing two hydrogen atoms from a compound represented by formula (11), (12), or (13).

[0021] An insulating resin film containing a resin having an imide group can be formed, for example, by a method including applying a resin varnish containing a resin precursor onto a first semiconductor substrate or a second semiconductor substrate and heating the coating to form an insulating resin film containing a resin having an imide group. When forming an insulating resin film containing a polymer containing imide units (polyimide resin or polyamideimide resin), the resin precursor can be a polyamic acid having structural units corresponding to the imide units. A curing reaction, including an imidization reaction, occurs upon heating the coating, thereby forming an insulating resin film containing a polyimide resin or a polyamideimide resin. When forming an insulating resin film containing a resin containing a polysiloxane bonded to imide units, the resin precursor can include a combination of a polycarboxylic acid compound corresponding to the imide units and a polysiloxane substituted with a substituent having an amino group. The polycarboxylic acid compound may include an anhydride or a carboxylic acid ester. An insulating resin film containing a resin having an imide group is formed by a reaction between the amino group of the substituent bonded to the polysiloxane and the polycarboxylic acid compound, followed by a curing reaction, including an imidization reaction.

[0022] The insulating resin film containing a polybenzoxazole resin can be formed, for example, by a method including: applying a resin varnish containing a resin precursor onto a first semiconductor substrate or a second semiconductor substrate; and heating the coating film to cause a curing reaction, including a reaction to form benzoxazole groups, thereby forming the insulating resin film containing a polybenzoxazole resin.

[0023] A portion of the second insulating resin film 23 formed so as to cover the entire second electrode 22 is removed so as to expose the second electrode 22. This forms a second bonding layer 25 having the second insulating resin film 23 with a plurality of openings 23 a and the second electrode 22 provided in each of the openings 23 a. For example, the portion of the second insulating resin film 23 is removed by chemical mechanical polishing (CMP). The second bonding surface S2, which is the surface of the second bonding layer 25 opposite to the second semiconductor substrate 21, may be a flat surface, or may have a convex portion or a concave portion formed at the position of the second electrode 22.

[0024] 2(d), after the second insulating resin film 23 is formed, the second semiconductor substrate 21 is fixed to a dicing tape 42, and in this state, the second semiconductor substrate 21 is divided by dicing together with the second insulating resin film 23. By the division, a second semiconductor member 20 having the second semiconductor substrate 21, which is a semiconductor chip, is formed on the dicing tape 42.

[0025] Prior to hybrid bonding, the second insulating resin film 23 is irradiated with ultraviolet light (UV) as shown in FIG. 2( e). The insulating resin film irradiated with ultraviolet light can be bonded well to other insulating resin films at relatively low temperatures. The ultraviolet light irradiation forms polar groups on the surface of the second insulating resin film 23, which is thought to contribute to improved bonding at low temperatures.

[0026] The cumulative amount of ultraviolet light irradiated onto the second insulating resin film 23 can be adjusted to obtain an appropriate bond, taking into consideration conditions such as the heating temperature employed for hybrid bonding. For example, when the cumulative amount of ultraviolet light irradiated onto the second insulating resin film 23 is 500 mJ / cm ２ More than 20000mJ / cm ２ The cumulative amount of ultraviolet light irradiated onto the second insulating resin film 23 may be 600 mL / cm or less. ２ Above, 700mL / cm ２ Above, 800mL / cm ２ Above, 900mL / cm ２ Above, 1000mL / cm ２ Above, 1100mL / cm ２ Above, 1200mL / cm２ Above, 1300mL / cm ２ Above, 1400mL / cm ２ Above, 1500mL / cm ２ Above, 1600mL / cm ２ Above, 1700mL / cm ２ or more, or 1800 mL / cm ２ or more, 19000 mJ / cm ２ Below, 18000mJ / cm ２ Below, 17000mJ / cm ２ Below, 16000mJ / cm ２ Below, 15000mJ / cm ２ Below, 14000mJ / cm ２ Below, 13000mJ / cm ２ Below, 12000mJ / cm ２ Below, 11000mJ / cm ２ Below, 10000mJ / cm ２ or less, or 9000 mJ / cm ２ It may be the following:

[0027] The second insulating resin film 23 is irradiated with ultraviolet light before the first semiconductor member 10 and the second semiconductor member 20 are bonded together. The second insulating resin film 23 may also be irradiated with ultraviolet light before being divided by dicing.

[0028] 2(f) can also be prepared by a method similar to the method exemplified above for preparing the second semiconductor member 20. The first semiconductor member 10 has a first bonding layer 15 that has a first insulating resin film 13 having a plurality of openings 13a and a first electrode 12 provided in each of the openings 13a.

[0029] The diameter of the semiconductor wafer serving as the first semiconductor substrate 11 may be, for example, 150 mm or more and 300 mm or less, and the thickness of the semiconductor wafer serving as the first semiconductor substrate 11 may be, for example, 40 μm or more and 1000 μm or less.

[0030] The first electrode 12 can be a conductor containing, for example, copper. The width (maximum width) of the first electrode 12 may be, for example, 1 μm or more and 13 μm or less. The height of the first electrode 12 may be, for example, 1 μm or more and 90 μm or less. A through electrode that penetrates the first semiconductor substrate 11 may be provided. The first bonding surface S1, which is the surface of the first bonding layer 15 opposite to the first semiconductor substrate 11, may be a flat surface, or a convex portion or a concave portion may be formed at the position of the first electrode 12.

[0031] Before bonding the first semiconductor member 10 and the second semiconductor member 20, the first insulating resin film 13 may be irradiated with ultraviolet light. Both the first insulating resin film 13 and the second insulating resin film 23 may be irradiated with ultraviolet light, or only one of the first insulating resin film 13 and the second insulating resin film 23 may be irradiated with ultraviolet light.

[0032] 2 and 3 , a plurality of second semiconductor members 20 picked up from the dicing tape 42 are joined by hybrid bonding to one first semiconductor member 10 fixed to the dicing tape 41. The second semiconductor member 20 is positioned on the second bonding surface S2 such that the first electrode 12 and the second electrode 22 are arranged opposite each other, with the first bonding surface S1 and the second bonding surface S2 facing each other. In this state, the first semiconductor member 10 and the second semiconductor member 20 are pressed together while being heated to a predetermined heating temperature, thereby joining the first semiconductor member 10 and the second semiconductor member 20 ((g) of FIG. 3 ).

[0033] The process of bonding the first semiconductor member 10 and the second semiconductor member 20 may include pre-bonding, in which the first semiconductor member 10 and the second semiconductor member 20 are heated and compressed to bond the first insulating resin film 13 and the second insulating resin film 23, and annealing, in which the entire stack including the first semiconductor member 10 and a plurality of second semiconductor members 20 is heated and pressurized to bond the first electrode 12 and the second electrode 22. In the case of a method including pre-bonding and annealing, the first insulating resin film 13 and the second insulating resin film 23 are primarily bonded together during the pre-bonding stage, and the first electrode 12 and the second electrode 22 are primarily metal-bonded together during the annealing stage. However, the first electrode 12 and the second electrode 22 may be bonded to some extent during the pre-bonding stage. Furthermore, the first insulating resin film 13 and the second insulating resin film 23 may be bonded even more strongly during the annealing stage.

[0034] If the first insulating resin film 13, the second insulating resin film 23, or both are irradiated with ultraviolet light before hybrid bonding, the insulating resin films can be bonded well even at a low heating temperature. The heating temperature for preliminary bonding may be the same as or lower than the annealing temperature for bonding the electrodes. The heating temperature for bonding (preliminary bonding) the first insulating resin film 13 and the second insulating resin film 23 may be, for example, 180°C or higher and 250°C or lower. This heating temperature may be 240°C or lower, 230°C or lower, or 220°C or lower, or may be 190°C or higher, or 200°C or higher. The pressure for preliminary bonding may be, for example, 0.5 MPa or higher and 10 MPa or lower. The heating and pressurizing time for preliminary bonding may be, for example, 3 seconds or higher and 120 minutes or lower.

[0035] In the annealing, a laminate including the first semiconductor member 10 and the plurality of second semiconductor members 20 is heated and pressurized, for example, in a pressure oven. The heating temperature for annealing is adjusted so as to form a metal bond, and may be, for example, 190°C or higher and 400°C or lower. The heating temperature for annealing may be 200°C or higher, 210°C or higher, 220°C or higher, 230°C or higher, 240°C or higher, 250°C or higher, or 260°C or higher, and may be 390°C or lower, 380°C or lower, 370°C or lower, 360°C or lower, or 350°C or lower. The pressure for annealing may be, for example, 0.1 MPa or higher and 5 MPa or lower. The heating and pressurizing time for annealing may be, for example, 10 minutes or higher and 120 minutes or lower.

[0036] When the first electrode 12 and the second electrode 22 are metal-bonded at a relatively low temperature, the first electrode 12 and the second electrode 22 can be sufficiently bonded at the temperature of the preliminary bonding. In this case, the first insulating resin film 13 and the second insulating resin film 23 may be bonded, and the first electrode 12 and the second electrode 22 may also be bonded by a single-stage compression bonding.

[0037] After the first semiconductor member 10 and the second semiconductor member 20 are bonded together, the first semiconductor member 10 bonded to the second semiconductor member 20 is divided by dicing, as shown in (h) of Fig. 3. As a result, a semiconductor chip stack 30 including the first semiconductor member 10 and the second semiconductor member 20, each having a first semiconductor substrate singulated into semiconductor chips, is formed on the dicing tape 41. Thereafter, the semiconductor chip stack 30 (semiconductor device) is picked up from the dicing tape 41, as shown in (i) of Fig. 3.

[0038] The present invention is not limited to the following test examples. (Test 1) A test semiconductor chip stack in which a lower semiconductor member and an upper semiconductor member were bonded was prepared according to the following procedure, and the shear peel strength of the bonding surface was measured. First, a large number of copper pillars (electrodes) measuring 10 μm square and 4 μm high were formed on a silicon wafer for the upper semiconductor member. A resin varnish containing polyamic acid was applied to the silicon wafer with the copper pillars, and the coating was cured by heating at 250°C to form an insulating resin film containing polyimide resin (PI) and covering the copper pillars. The insulating resin film was polished using a CMP method to form a bonding layer for the upper semiconductor member, including exposed copper pillars and an insulating resin film (thickness: 3.9 μm) filling the surrounding area. The upper semiconductor member was fixed on dicing tape, and then diced using a blade dicer to form an upper semiconductor member having a singulated semiconductor chip and a bonding layer. The singulated semiconductor chips measured 4 mm x 4 mm. The entire surface of the insulating resin film on the semiconductor chip was irradiated with ultraviolet light, and the cumulative amount of ultraviolet light was adjusted by adjusting the exposure time.

[0039] Copper pillars and an insulating resin film filling the periphery of the copper pillars were formed on a silicon wafer for the lower semiconductor member in the same manner as for the lower semiconductor member, thereby obtaining a lower semiconductor member having a silicon wafer and a bonding layer. After the insulating resin film was irradiated with ultraviolet light, the upper semiconductor member was picked up from the dicing tape, and the copper pillars of the upper semiconductor member and the copper pillars of the lower semiconductor member were aligned. The upper semiconductor member was then pressed against the lower semiconductor member so that the copper pillars were in contact with each other, thereby pre-bonding the lower and upper semiconductor members. During this pre-bonding, the lower and upper semiconductor members were heated to 210°C. After pre-bonding, the formed pre-bonded body was annealed in a pressurized oven in a nitrogen atmosphere at a predetermined annealing temperature (210-300°C) for 120 minutes, thereby metallurgically bonding the copper pillars together.

[0040] After annealing, the silicon wafer of the lower semiconductor member was diced on the dicing tape using a blade dicer to separate into semiconductor chips. Each of the separated semiconductor chips had a size of 8 mm x 8 mm, and one upper semiconductor member was joined to one lower semiconductor member by hybrid bonding. A test semiconductor chip stack consisting of the lower semiconductor member and the upper semiconductor member was picked up from the dicing tape.

[0041] The test semiconductor chip stack was fixed on a stage at 260° C., and a jig pressed against the side surface of the upper semiconductor member was moved at a speed of 20 μm / min to apply shear stress to the upper semiconductor member. The shear strength of the hybrid-bonded joint surface was determined from the stress at the time when the upper semiconductor member peeled off from the lower semiconductor member.

[0042] The fabrication conditions and shear strength of the test semiconductor chip stacks are shown in Table 1. #1 to #3 are examples of test semiconductor chip stacks fabricated without exposing the insulating resin film to light before pre-bonding. Test semiconductor chip stacks #4 to #7, in which the insulating resin film was irradiated with ultraviolet light before pre-bonding, exhibited higher shear strength than semiconductor chip stack #1, which was not irradiated with ultraviolet light, and also exhibited higher shear strength than semiconductor chip stack #3, which was annealed at a high temperature of 300°C without ultraviolet light irradiation.

[0043]

[0044] (Test 2) A test semiconductor chip stack was fabricated in the same manner as Test 1, except that an insulating resin film containing polybenzoxazole resin (PBO) was formed instead of the insulating resin film containing polyimide resin, and its shear strength was measured. The fabrication conditions and shear strength of the semiconductor chip stack are shown in Table 2. It was confirmed that in the case of an insulating resin film containing polybenzoxazole resin, the shear strength increased even at a low pre-bonding temperature due to ultraviolet irradiation before pre-bonding.

[0045]

[0046] 10...first semiconductor member, 11...first semiconductor substrate, 12...first electrode, 13...first insulating resin film, 13a...opening, 20...second semiconductor member, 21...second semiconductor substrate, 22...second electrode, 23...second insulating resin film, 23a...opening, 30...semiconductor chip stack (semiconductor device), UV...ultraviolet light

Claims

1. preparing a first semiconductor member having a first semiconductor substrate and a first bonding layer provided on the first semiconductor substrate, the first bonding layer including a first electrode and a first insulating resin film, the first insulating resin film having an opening, and the first electrode provided in the opening; preparing a second semiconductor member having a second semiconductor substrate and a second bonding layer provided on the second semiconductor substrate, the second bonding layer including a second electrode and a second insulating resin film, the second insulating resin film having an opening, and the second electrode provided in the opening; irradiating at least one of the first insulating resin film and the second insulating resin film with ultraviolet light; Joining the first semiconductor member and the second semiconductor member by hybrid joining in which the first electrode and the second electrode are joined and the first insulating resin film and the second insulating resin film are joined; Including, Bonding the first semiconductor member and the second semiconductor member includes pressing the first semiconductor member and the second semiconductor member together while heating them to a temperature of 180°C or higher and 250°C or lower, thereby bonding the first insulating resin film and the second insulating resin film. A method for manufacturing a semiconductor device.

2. preparing a first semiconductor member having a first semiconductor substrate and a first bonding layer provided on the first semiconductor substrate, the first bonding layer including a first electrode and a first insulating resin film, the first insulating resin film having an opening, and the first electrode provided in the opening; preparing a second semiconductor member having a second semiconductor substrate and a second bonding layer provided on the second semiconductor substrate, the second bonding layer including a second electrode and a second insulating resin film, the second insulating resin film having an opening, and the second electrode provided in the opening; irradiating at least one of the first insulating resin film and the second insulating resin film with ultraviolet light; Joining the first semiconductor member and the second semiconductor member by hybrid joining in which the first electrode and the second electrode are joined and the first insulating resin film and the second insulating resin film are joined; Including, the first insulating resin film and the second insulating resin film contain a resin containing an imide group, and the resin containing an imide group is a resin having a structural unit containing an imide group and a polysiloxane bonded to the structural unit; A method for manufacturing a semiconductor device.

3. the first semiconductor substrate is a semiconductor wafer, the second semiconductor substrate is a semiconductor chip, and a plurality of the second semiconductor members are bonded to one of the first semiconductor members; 3. The method of claim 1 or 2, further comprising dividing the first semiconductor member bonded to the second semiconductor member, thereby forming a semiconductor chip stack including the first semiconductor member and the second semiconductor member, each having the first semiconductor substrate singulated into semiconductor chips.

4. The method of claim 1 , wherein the first insulating resin film and the second insulating resin film contain a resin containing an imide group.

5. The method of claim 4 , wherein the resin containing imide groups is a polyimide resin, a polyamideimide resin, a bismaleimide resin, or a combination thereof.

6. The method according to claim 4, wherein the resin containing an imide group is a resin having a structural unit containing an imide group and a polysiloxane bonded to the structural unit.

7. The method of claim 1 , wherein the first insulating resin film and the second insulating resin film comprise a polybenzoxazole resin.

8. The method of claim 1 , wherein the first insulating resin film and the second insulating resin film comprise a benzocyclobutene resin.