JP6376649B2 - Method for manufacturing through electrode substrate - Google Patents

Description

  The present invention relates to a method for manufacturing a through electrode substrate using a fluid containing conductive nanoparticles when forming a through electrode. The through electrode substrate manufactured according to the present invention is used in a package field such as an interposer and a semiconductor field such as TSV.

As a conventional glass substrate with a through electrode, for example, a configuration in which a tungsten wire or an iron / nickel / cobalt alloy core is used as an electrode material is disclosed (Patent Documents 1 and 2).
Although the glass substrate with a through electrode having the above-described structure is characterized by high airtightness, it must be heated to a high temperature near the melting temperature of the glass serving as a base material because of its manufacturing method. Therefore, the glass substrate may be damaged due to the difference in thermal expansion coefficient between the glass and the electrode material. Therefore, a limited metal such as tungsten having a thermal expansion coefficient close to that of glass is used. That is, when the through electrode is formed by the above manufacturing method, there is a problem that the selection range of the electrode material is narrow.

  Moreover, since the said manufacturing method requires the process heated to the temperature which glass deform | transforms, the flatness of the surface of a glass substrate is easy to be impaired. Therefore, in order to use by bonding to another substrate on which a semiconductor, MEMS, or the like is formed, the glass substrate with a through electrode obtained by the above manufacturing method needs to be polished after the through electrode is formed. It becomes. However, in order to polish the surface of the substrate in which the metal electrode is embedded in the glass, there is a problem that a special polishing technique is required and the process becomes complicated.

As another method for forming a substrate with a through electrode (TSV, TGV), there is a hole filling by plating, but it is difficult to obtain sufficient airtightness in a high aspect and fine hole.
Also, the normal conductive particles larger than the nano-sized particle size, or the sintering temperature of the ink paste containing these, generally requires a high temperature of 500 ° C. or more, and the difference in thermal expansion coefficient from glass The problem due to.

  A method of forming an electrode at a low temperature by mixing a binder that remains after baking such as frit glass is also possible, but the resistance value increases because the binder is included. Furthermore, when joining the substrate with a through electrode to another substrate on which a semiconductor, MEMS, or the like is formed, the binder must be processed at a temperature lower than the molding temperature so that the softening of the binder does not start, and the usable range is narrow. turn into. (In general, a process temperature of about 400 ° C. is required for anodic bonding of borosilicate glass and a silicon wafer.)

JP 2011-151414 A JP 2006-60119 A

  The present invention has been made in view of the above circumstances, and it is not necessary to consider the difference in thermal expansion coefficient between the glass substrate and the through electrode, and it is not necessary to polish the glass substrate after the through electrode is formed. An object of the present invention is to provide a method of manufacturing a through electrode substrate capable of forming a through electrode having a high height.

According to a first aspect of the present invention, there is provided a method for manufacturing a through electrode substrate, comprising: a first step of forming a through hole inside the base with respect to one surface of a base made of flat glass; and the first step. A second step of sealing the through-hole on the other surface side by applying a film-like sealing material to the other surface of the substrate that has undergone, and the penetration from the one surface side of the substrate that has undergone the second step The third step of forming the through electrode by filling the fluid A containing conductive nanoparticles in the pores and sintering the conductive nanoparticles at a temperature lower than the heat resistance temperature of the sealing material. When, only contains, further wherein between the second step and the third step, to the inner surface of the second through-hole formed by the process, the fluid C composed of alkoxysilanes based sol-gel solution characterized in that it comprises the steps alpha, of forming a film by using a
According to a second aspect of the present invention, there is provided a method for manufacturing a through electrode substrate comprising: a first step of forming a through hole in the base of one surface of the base made of flat glass; and the first step. A second step of sealing the through-hole on the other surface side by applying a film-like sealing material to the other surface of the substrate that has undergone, and the penetration from the one surface side of the substrate that has undergone the second step The third step of forming the through electrode by filling the fluid A containing conductive nanoparticles in the pores and sintering the conductive nanoparticles at a temperature lower than the heat resistance temperature of the sealing material. And when the micropores remain inside the through electrode, a fluid β made of an alkoxylane-based sol-gel solution is used to fill and repair the micropores β,
It is characterized by providing.
According to a third aspect of the present invention, there is provided a method for manufacturing the through electrode substrate according to the first or second aspect , wherein in the first step, a base having a recess formed in advance on the other surface of the base is used. to.

According to Claim 4 of the present invention, in the method of manufacturing a through electrode substrate according to Claim 2 , the step β is a step of putting the substrate that has undergone the third step into a sealed container and exhausting the inside of the sealed container. and .beta.1, the sealed container inherent said through the steps .beta.1 substrate, while exhausting the inside of the sealed vessel, introducing a flow body E in the interior of the sealed container, said substrate is immersed in fluid element E A state β2, a step β3 in which pressure is applied to the substrate that has undergone the step β2 via the fluid E, and a fluid that has been removed from the sealed container and has adhered to the outer surface of the substrate A step β4 for removing E, a step β5 for pre-baking the substrate by providing a fourth heating means on the other surface side of the substrate after the step β4, and a fifth surface on the other surface side of the substrate after the step β5. By providing a heating means and firing the substrate And a step β6 for forming a through electrode in which the micropores are repaired, and a step β7 for removing the fifth heating means from the substrate that has undergone the step β6 and cleaning the substrate. To do.

Through electrode substrate according to claim 5 of the present invention, a through electrode substrate comprising a through electrode on a substrate, the through electrode Ri Do conductive nanoparticles provided in the through hole of the base body An adhesive layer made of a coating formed from an alkoxylane-based sol-gel solution is disposed on the inner surface of the through hole .
The through electrode substrate according to claim 6 of the present invention is a through electrode substrate comprising a through electrode on a base, the through electrode being made of conductive nanoparticles provided in a through hole of the base, The micropores present in the through electrode are filled with a formation using an alkoxylane-based sol-gel solution.

  In the present invention, the through-hole provided in the substrate made of glass is filled with the fluid A containing conductive nanoparticles, and then the substrate is subjected to pre-bake treatment and firing treatment to form a through electrode. The conductive nanoparticles can be fired at a low temperature of 500 ° C. or lower. Therefore, since the difference in thermal expansion between the glass forming the substrate and the material forming the through electrode can be smaller than in the past, there is no need to consider the difference in the thermal expansion coefficient between the glass substrate and the through electrode, and the method for manufacturing the through electrode substrate Is obtained. Thereby, since limitation of the element which comprises electroconductive nanoparticle is relieve | moderated, it becomes possible to select various materials other than tungsten. Therefore, according to the present invention, it is possible to manufacture a through electrode substrate having a through electrode made of an element that provides desired conductivity.

  Further, after the fluid A containing conductive nanoparticles adhered to one surface of the substrate is shaken off, heat treatment is performed, a through electrode is formed inside the through hole of the substrate, and then the film is removed from the substrate. Flatness is naturally secured on the upper and lower surfaces of the through electrode exposed on the one surface side and the other surface side. Therefore, this invention contributes to provision of the manufacturing method of a through-electrode board | substrate which does not need the grinding | polishing of a glass substrate after formation of a through-electrode.

  Further, the solvent contained in the fluid A is first volatilized by pre-baking treatment with respect to the fluid A containing the conductive nanoparticles filled in the through holes of the substrate. Thereafter, the conductive nanoparticles contained in the fluid A are sintered by a firing process, whereby conductive through electrodes are formed in the through holes. In the case where the fluid A is, for example, an ink paste containing conductive nanoparticles, a dispersant is adsorbed on the particle surface in order to develop the dispersion stability of the particles. In the present invention, the solvent is removed by pre-bake treatment, and the dispersing agent is separated and removed by the firing process, which is the next step, so that the sintering of the particles proceeds efficiently and a highly airtight through electrode is formed. It becomes possible.

  The fluid A according to the present invention is not limited to the above-described ink paste containing conductive nanoparticles, and may be used in the form of powder composed of conductive nanoparticles adsorbed with a dispersant. good. However, when used in a powder state, it is preferable that the temperature of the pre-bake treatment is set to a temperature at which the dispersing agent starts to be detached, and the baking treatment that is the next step is performed at a higher temperature.

The flowchart which shows the manufacturing method of the penetration electrode substrate concerning the present invention. The flowchart (1st embodiment) containing an example of the 3rd process shown in FIG. The schematic cross section which shows the manufacturing method based on FIG. 2 in order of a process. The schematic cross section which shows each process following FIG. 3 in order. The flowchart containing other examples of the 3rd process shown in FIG. 1 (2nd embodiment). The schematic cross section which shows an example of the manufacturing method based on FIG. 5 in order of a process. The schematic cross section which shows each process following FIG. 6 in order. 7 is a flowchart including another example of the third step shown in FIG. 1 (third embodiment). The schematic cross section which shows an example of the manufacturing method based on FIG. 8 in order of a process. The schematic cross section which shows each process following FIG. 9 in order. FIG. 11 is a schematic cross-sectional view sequentially illustrating each step following FIG. 10. FIG. 9 is a flowchart provided in the subsequent stage of FIGS. 2, 5, and 8. FIG. 12 is a schematic cross-sectional view sequentially illustrating steps added after the final step of FIGS. 4, 7, and 11. FIG. 14 is a schematic cross-sectional view sequentially illustrating each step following FIG. 13.

Below, the manufacturing method of the penetration electrode substrate concerning the present invention is explained based on a drawing.
FIG. 1 is a flowchart showing a method for manufacturing a through electrode substrate according to the present invention, which includes the following three steps.
A first step of forming a through hole from one surface of the substrate toward the other surface.
A second step of sticking a film to the other surface of the substrate and sealing the through hole on the other surface side.
A third step of forming a through electrode by introducing a fluid containing conductive nanoparticles on one surface of the substrate and sintering the conductive nanoparticles contained in the fluid in the through hole.
Through the above three steps, the through electrode substrate according to the present invention is obtained.
In the present invention, “conductive nanoparticles”, which is a material that is mixed into a fluid and becomes a through electrode (or wiring pattern) by subsequent heat treatment, is also referred to as a starting material.

In the present invention, among the above three steps, the third step is a characteristic part. Due to the difference in the third step, there are three types of embodiments described below.
First embodiment: When a fluid containing conductive nanoparticles is filled into a through hole and sintered to form a through electrode (applied to a flat substrate).
Second embodiment: When the manufacturing method of the first embodiment is applied to a substrate having a recess.
Third embodiment: A case where the manufacturing method of the first embodiment is applied after a film is formed on the side surface of the through hole with a sol-gel solution.
The fourth embodiment is an additional work of the above three embodiments. That is, in the fourth embodiment, the micropores remaining inside the through electrode are repaired using the substrate on which the through electrode has already been formed according to the above three embodiments.
Below, 1st embodiment-4th embodiment are described in order.

<First embodiment>
2 to 4 are drawings according to the first embodiment, FIG. 2 is a flow chart, FIG. 3 is a schematic cross-sectional view showing an example of the manufacturing method based on FIG. 2, and FIG. It is a schematic cross section which shows a process in order.

As shown in FIG. 1, the manufacturing method of the first embodiment includes the following seven steps, and particularly SA3 to SA6 correspond to the third step.
The through-hole 12 is formed from one surface of the substrate 10 toward the other surface [SA1 (first step): FIG. 3A].
At that time, a film 11 is provided in advance on one surface of the substrate 10 as necessary.
-The film 13 is stuck on the other surface of the substrate 10, and the through hole 12 is sealed on the other surface side [SA2 (second step): FIG. 3 (b)].
A fluid A14 containing conductive nanoparticles is applied to one surface of the substrate 10, and the fluid A14 is filled in the through holes 12 [SA3 (third step): FIG. 3 (c)].
The substrate 10 is rotated to shake off the fluid A14 attached on one surface of the substrate [SA4 (third step): FIG. 3 (d)].
The substrate 10 is pre-baked using the heating means 16a [SA5 (third step): FIG. 4 (e)].
The through-electrode 14A is formed by baking the substrate 10 using the heating means 16b [SA6 (third step): FIG. 4 (f)].
After removing the heating means 16b and removing the films 11 and 13 from the substrate 10, the substrate 11 is washed [SA7 (fourth step): FIG. 3 (g)].
Through the above seven steps, the through electrode substrate SA is obtained.

  In the first step (SA1), a substrate made of glass is prepared as the base 10 and, for example, sandblasting (hereinafter referred to as blasting) is performed from one surface (upper surface in FIG. 2) to the other surface (lower surface in FIG. 2). Through holes 12 are also formed. At that time, a masking dry film 11 having an opening at a position corresponding to the through hole is frequently used on one surface of the substrate. Further, the dry film used for blasting masking can be left without peeling and used as a protective film or masking film in post-processing. Furthermore, when used for a protective film / masking film, it is effective to use polyimide having high heat resistance.

  As the substrate 10 made of the glass, a substrate having a flat and clean surface was previously polished. In addition, various kinds of glass such as soda lime glass, non-alkali glass, white plate, and quartz can be used as the glass. In the present embodiment, the case where the substrate is a substrate made of glass will be described in detail. However, even if a substrate other than glass, for example, a substrate such as silicon, SiC, or ceramics, is used as the substrate, the manufacturing method of the present invention is applicable. Is possible.

  The through hole processing method is not limited to the blast processing described above, and, for example, a dry etching method, laser processing, machining, or the like can be appropriately employed. Depending on the processing method, it is not necessary to provide the dry film 11 used in the blasting method. Moreover, the design of the size and pitch of the through holes is also free. In laser processing, a through hole having a diameter of up to about 0.02 mm is possible, which is desirable when a finer through electrode is required. When a finer through electrode is required, a dry etching method can be used. At this time, it is desirable to protect the surface in advance with a film of a heat resistant material such as polyimide or a coating solution.

  In the second step (SA2), a polyimide film 13 is formed on the other surface of the glass substrate 10 in which the through hole 12 has been processed in the previous step (SA1) (the lower surface in FIG. Apply using a laminator.

The third step includes the following four steps (SA3 to SA6).
In the first step (SA3), the fluid A14 containing conductive nanoparticles is applied to one surface of the substrate 10 on which the film 13 is provided on the other surface in the previous step (SA2), whereby the fluid flows into the through hole 12. Fill body A14. At that time, the fluid A <b> 14 is dispensed in a paddle shape on one surface of the substrate 10.
The ink filling method is not limited to the dispensing method, and the through hole may be filled with another method such as a printing method or a suction method.

As the fluid A14 containing conductive nanoparticles, for example, an ink containing Ag particles having an average particle diameter of 3.8 nm as conductive particles (solid component concentration: 58 wt%, viscosity: 10 mPs · s, density: 1.7 g / cm ³ , solvent: tetradecane) is preferably used. As such an ink, for example, nanometal ink manufactured by ULVAC, Inc. may be mentioned.

  In the second step (SA4), excess ink (fluid A14) adhered on one surface of the substrate 10 is rotated by rotating the substrate 10 coated with the fluid A14 from one surface side of the substrate 10 in the previous step (SA3). Shake off. Thereby, the ink (fluid A14) forming the upper surface of the through-hole 12 exposed on one surface side of the substrate 10 is flattened. However, instead of the “rotating and shaking method”, a method of removing excess ink (fluid A14) using a squeegee and flattening the ink (fluid A14) forming the upper surface of the through hole 12 is used. May be.

  In the third step (SA5), the substrate 10 on which the ink (fluid A14) that forms the upper surface of the through hole 12 in the previous step (SA4) has been planarized is pre-baked using the heating means 16a. At that time, the surface of the substrate 10 on which the ink (fluid A14) is flattened is the upper surface, and the other surface of the substrate 10 (the surface to which the film 13 is attached) is the lower surface. A heating means 16a is provided so that heat is conducted to the base 10 via the. Thereby, the prebaking process of the base | substrate 10 is performed using the heating means 16a.

Such a pre-baking process is performed using the heating means 16a which consists of a hot plate, for example. The purpose of the pre-baking process is to volatilize the solvent contained in the ink, and is performed, for example, under conditions of 70 ° C. and 30 minutes.
If the fluid A14 is not sufficiently filled into the through-hole 12, the steps from filling to pre-baking (SA3, SA4, SA5) may be repeated a plurality of times.

  3 to 4 show examples in which each process is performed while leaving the dry film 11 provided on one surface (upper surface) of the substrate 10 as masking during blasting. The dry film 11 is heat resistant. In the case of a film having low properties, the film 11 is peeled off at this point (before the pre-bake treatment: between SA4 and SA5). When the file 11 is a film having high heat resistance, the state can be left as it is (the process proceeds to SA5 and subsequent steps without removing the film 11).

In the fourth step (SA6), the substrate 11 in which the solvent is volatilized from the ink (fluid A14) filled in the through holes in the previous step (SA5) is baked using the heating means 16b, A through electrode 14A is formed.
Such a baking process is performed using the heating means 16b which consists of a hotplate, for example. The purpose of the baking treatment is to solidify the ink (fluid A14) filled in the through holes, and is performed, for example, under conditions of 300 ° C. and 1 hour lower than the heat resistant temperature of polyimide.

  In the description of the fourth step (SA6), the case where the fluid A14 is made of ink paste has been described in detail. However, the fluid A according to the present invention is not limited to the ink paste containing the conductive nanoparticles described above, and may be used in the form of powder composed of conductive nanoparticles adsorbed with a dispersant. good. However, when used in a powder state, it is preferable that the temperature of the pre-bake treatment is set to a temperature at which the dispersing agent starts to be detached, and the baking treatment that is the next step is performed at a higher temperature.

In the fourth step (SA7), the heating means 16b is removed from the base 10 in which the ink (fluid A14) filled in the through holes in the previous step (SA6) is solidified to form the through electrodes 14A. After removing the films 11 and 13 from the substrate 10, the substrate 10 is washed.
The operation of removing (peeling) the films 11 and 13 from the substrate 10 is performed after the substrate 10 is cooled to a desired temperature or lower. The cleaning process of the substrate 10 is performed using, for example, a glass substrate detergent / pure water. Thereafter, it is preferable to perform IPA vapor drying.

In 1st embodiment, penetration electrode board SA provided with penetration electrode 14A (MA) was produced by passing through SA1-SA7 mentioned above. Therefore, the through electrode substrate SA according to the first embodiment is a through electrode substrate in which a base is provided with a through electrode, and the through electrode is composed of conductive nanoparticles provided in a through hole of the base. ing.
The airtightness of the through electrode 14A constituting the manufactured through electrode substrate SA is determined by a vacuum spraying method (JIS Z2331, Annex 1 (→ http: //kikakurui.com/z2/Z2331-2006-01.html)). Evaluated. As a result, the airtightness of the through electrode 14A was 1 × 10 ⁻⁹ [Pa · m ³ / sec] or less, and it was confirmed that the through electrode 14A has a good airtightness.

<Second embodiment>
5 to 7 are drawings according to the second embodiment, FIG. 5 is a flowchart, FIG. 6 is a schematic cross-sectional view showing an example of the manufacturing method based on FIG. 5, and FIG. It is a schematic cross section which shows a process in order.

The manufacturing method of 2nd embodiment contains the following 8 processes, as shown in FIG.
As shown in FIG. 5, the manufacturing method of the second embodiment includes the following eight steps, and SB4 to SB7 particularly correspond to the third step.
A recess 20C is formed on the other surface of the substrate 20 [SB1 (previous process): FIG. 6A].
The through hole 22 is formed from one surface of the base 20 toward the other surface [SB2 (first step): FIG. 6B].
At that time, if necessary, a film 21 is provided in advance on one surface of the substrate 20.
-The film 23 is stuck on the other surface of the base body 20, and the through hole 22 is sealed on the other surface side [SB3 (second step): FIG. 6 (c)].
The fluid B24 containing conductive nanoparticles is applied to one surface of the substrate 20, and the fluid B24 is filled in the through holes 22 [SB4 (third step): FIG. 6 (d)].
The substrate 20 is rotated to shake off the fluid B24 attached on one surface of the substrate [SB5 (third step): FIG. 7 (e)].

Pre-bake processing of the base 20 using the heating means 26a [SB6 (third step): FIG. 7 (ef).
The through electrode 24A is formed by baking the base body 20 using the heating means 26b [SB7 (third step): FIG. 7 (g)].
After removing the heating means 26b and removing the films 21 and 23 from the base 20, the base 20 is washed [SB8 (fourth step): FIG. 7 (h)]. Eighth step [SB8: FIG. 6 (h)].
Through the above eight steps, the through electrode substrate SB provided with the through electrode 24A (MA) is obtained.

  In the previous step (SB1), a substrate made of glass is prepared as the base 20, and a recess 20C having a desired depth is formed from the other surface (lower surface in FIG. 6) to one surface (upper surface in FIG. 6). To do. As a method for forming the recess 20C, for example, a method disclosed in JP2013-022534A can be cited.

  As the substrate 20 made of the above glass, a substrate that had been polished in advance and had a flat and clean surface was used. In addition, various kinds of glass such as soda lime glass, non-alkali glass, white plate, and quartz can be used as the glass. In the present embodiment, the case where the substrate is a substrate made of glass will be described in detail. However, even if a substrate other than glass, for example, a substrate such as silicon, SiC, or ceramics, is used as the substrate, the manufacturing method of the present invention is applicable. Is possible.

  In the second step (SB2), for example, sandblasting (hereinafter referred to as blasting) is performed from one surface (upper surface in FIG. 6) to the other surface (lower surface in FIG. 6) from one surface (upper surface in FIG. 6) on which the recess 20C is formed in the previous step (SB1). Through holes 22 are formed by a process). At that time, a masking dry film 21 having an opening at a position corresponding to the through hole is frequently used on one surface of the substrate. Further, the dry film used for blasting masking can be left without peeling and used as a protective film or masking film in post-processing. Furthermore, when used for a protective film / masking film, it is effective to use polyimide having high heat resistance.

  The second step (SB3), the third step (SB4, SB5, SB6, SB7) and the fourth step (SB8) are respectively the second step (SA2) and the third step (SA3, SA4) in the first embodiment described above. , SA5, SA6) and the fourth step (SA7). The second embodiment is different from the first embodiment only in that the glass substrate 20 has a recess 20C.

In 2nd embodiment, through each process (SB1-SB8) mentioned above, penetration electrode board SB provided with penetration electrode 24A (MA) was produced. Therefore, the through electrode substrate SB according to the second embodiment is a through electrode substrate having a through electrode on the base, similar to the above through electrode substrate SA, and the through electrode is placed in the through hole of the base. It is composed of provided conductive nanoparticles. The through electrode substrate SB differs from the through electrode substrate SA only in that the through electrode substrate SB includes a recess 20C.
The airtightness of the through electrode 24A constituting the manufactured through electrode substrate SB was evaluated using a vacuum spraying method, as in the first embodiment. As a result, the airtightness of the through electrode 24A was 1 × 10 ⁻⁹ [Pa · m ³ / sec] or less, and it was confirmed that the through electrode 24A has a good airtightness.

<Third embodiment>
8 to 11 are drawings according to the third embodiment, FIG. 8 is a flowchart, FIG. 9 is a schematic cross-sectional view illustrating an example of the manufacturing method based on FIG. 8, and FIG. FIG. 11 is a schematic cross-sectional view sequentially showing each step following FIG. 10.

  In the manufacturing method of the third embodiment, the above-described “third step” includes a step of forming a film on the side surface of the through hole with a sol-gel solution and a step of filling a fluid into the through hole.

As shown in FIGS. 8 to 11, the manufacturing method according to the third embodiment includes the following steps.
A through hole 32 is formed from one surface of the substrate 30 to the other surface [SC1 (first step): FIG. 9A].
At that time, a film 31 is provided in advance on one surface of the substrate 30 as necessary.
A film 33 is stuck on the other surface of the substrate 30, and the through hole 32 is sealed on the other surface side [SC2 (second step): FIG. 9B].
A fluid C37 made of an alkoxylane-based sol-gel solution is applied to one surface of the substrate 30, and the fluid C37 is filled in the through holes 32 [SC3 (third step): FIG. 9 (c)].
The substrate 30 is rotated to shake off the fluid C37 adhering to one surface of the substrate [SC4 (third step): FIG. 9 (d)].

The film 37F made of the fluid C37 is left on the side surface of the through hole 32, and the fluid C37 made of the sol-gel solution is removed from the inside of the through hole 32 [SC5 (third step): FIG. 10 (e)].
The substrate 30 is pre-baked using the heating means 36a [SC6 (third step): FIG. 10 (f)].
The fluid D34 containing conductive nanoparticles is applied to one surface of the substrate 30, and the fluid D34 is filled in the through holes 32 [SC7 (third step): FIG. 10 (g)].
The substrate 30 is rotated to shake off the fluid D34 adhering to one surface of the substrate [SC8 (third step): FIG. 10 (h)].

The substrate 30 is pre-baked using the heating means 36b [SC9 (third step): FIG. 11 (i)].
The through electrode 34 is formed by firing the substrate 30 using the heating means 36c [SC10 (third step): FIG. 11 (j)].
After removing the heating means 36c and removing the films 31 and 33 from the substrate 30, the substrate 30 is washed [SC11 (fourth step): FIG. 11 (k)].
Through the 11 steps described above, the through electrode substrate SC provided with the through electrode 34A (MA) is obtained.

  That is, in the third embodiment, the inner surface of the through hole formed by the second step (SC2) between the second step (SA2) and the third step (SA3) in the first embodiment. The second embodiment is different from the first embodiment in that it includes the step α [third step (SC3) to sixth step (SC6)] for forming a film using the fluid C made of a sol-gel solution.

Hereinafter, the process α different from the first embodiment will be described in detail. In the following description, the third step (SC3) to the sixth step (SC6) are also referred to as step α1 to step α4, respectively.
In the process α1 [third process (SC3)], the fluid C37 is applied to one surface of the substrate 30 on which the film 33 is provided on the other surface in the previous process (SC2), so that the fluid C is formed inside the through hole 32. Fill. Thereby, the state which the fluid C37 contacted with respect to the inner wall of the through-hole 32 is obtained.

  In step α2 [fourth step (SC4)], the substrate 30 is rotated so that an axis perpendicular to the surface of the substrate 30 that has undergone the previous step (α1) forms a rotation axis. Shake off the attached fluid C37. Thereby, the fluid C37 remaining on one surface of the substrate 30 is removed.

  In step α3 [fifth step (SC5)], liquid or gas is sprayed on one surface of the base body 30 that has undergone the previous step (α2), leaving the film 37F attached to the inner wall of the through-hole 32 while penetrating. The fluid C37 is removed from the inside of the hole 32. Thereby, the fluid C37 remaining on the base body 30 is only the film 37F attached to the inner wall of the through hole 32.

  In step α4 [sixth step (SC6)], the third heating means 36a is provided on the other surface side of the substrate 30 that has undergone the step (α3), and the substrate 30 is pre-baked. Thereby, the adhesiveness of the film 37 </ b> F made of the fluid C <b> 37 increases with respect to the inner wall of the through hole 32 provided in the base body 30.

In the next step [seventh step (SC7)], the conductive nanoparticles are applied to the through hole 32 prepared by the step α (α1 to α4) and having the film 37F made of the fluid C37 attached to the inner wall. By applying the fluid D34 containing, the fluid D34 is filled into the through holes 32.
Each process from the seventh process (SC7) to the eleventh process (SC11) is performed in the same manner as the third process (SA3) to the seventh process (SA7) in the first embodiment as described above. It is.

In the third embodiment, the through electrode substrate SC provided with the through electrode 34A (MA) was manufactured through the 11 steps (SC1 to SC11) described above. Therefore, the through electrode substrate SC according to the third embodiment is a through electrode substrate having a through electrode on a base, and an inner surface of the through hole is formed of a coating formed from an alkoxy run-based sol-gel solution. In addition, the through electrode is composed of conductive nanoparticles provided in the through hole of the substrate via the adhesive layer.
The airtightness of the through electrode 34A constituting the produced through electrode substrate SC was evaluated using a vacuum spraying method, as in the first embodiment. As a result, the airtightness of the through electrode 34A was 1 × 10 ⁻⁹ [Pa · m ³ / sec] or less, and it was confirmed that the through electrode 34A had good airtightness.

<Fourth embodiment>
12 to 14 are drawings according to the fourth embodiment. FIG. 12 is a flowchart, FIG. 13 is a schematic cross-sectional view showing an example of the manufacturing method based on FIG. 12, and FIG. It is a schematic cross section which shows a process in order.

As shown in FIG. 12, the manufacturing method of the fourth embodiment includes the following seven steps.
The fourth embodiment uses the fluid E made of a sol-gel solution when fine holes remain in the through electrodes formed on the substrate by the manufacturing method of the first to third embodiments described above. It repairs by filling the fine holes.
Seven steps in the fourth embodiment are collectively referred to as a step β. . In the following description, the first step (SD1) to the seventh step (SD7) are also referred to as step β1 to step β7, respectively.
Hereinafter, the process β will be described in detail.

In step β1 [first step (SD1)], the base body 40 on which the through electrode 44A is formed is placed in the sealed container C4 by the manufacturing method of the first to third embodiments described above, and the inside of the sealed container is evacuated. (P1). Thereby, the inside of the fine hole (hole P) existing in the through electrode 44A is deaerated.
In step β2 [second step (SD2)], the fluid E is placed inside the sealed container C4 while exhausting the inside (P2) of the sealed container C4 containing the substrate 40 that has undergone the process β1. (SGS) is introduced (P3), and the substrate 40 is immersed in the fluid E. that time. As the fluid E, an alkoxylane-based sol-gel solution is used.

In step β3 [third step (SD3)], pressure (P4) is applied via the fluid E to the substrate 40 that has undergone step β2. Thereby, the fluid E is injected into the inside of the hole P existing in the through electrode 44A.
In step β4 [fourth step (SD4)], the substrate 40 having undergone the step β3 is taken out from the sealed container C4, and the fluid E adhering to the outer surface of the substrate 40 is removed. As a result, the fluid E remaining on the outer surface of the substrate 40, in particular, the upper and lower surfaces of the through electrode is removed.

In step β5 [fifth step (SD5)], a fourth heating means 46a is provided on the other surface side of the substrate 40 that has undergone the step β4, and the substrate 40 is pre-baked.
In step [beta] 6 [sixth step (SD6)], the fifth heating means 46b is provided on the other surface side of the substrate that has undergone step [beta] 5, and the substrate 40 is baked to repair the fine holes (holes P). The formed through electrode 44Aa is formed.
In step β7 [seventh step (SD7)], the fifth heating means 46b is removed from the substrate 40 that has undergone the step β6, and the substrate 40 is cleaned.

In the fourth embodiment, the through electrode substrate SD including the through electrode 44Aa (MA) was manufactured through the above-described seven steps (SD1 to SD7). Therefore, the through-electrode substrate SD according to the fourth embodiment is a through-electrode substrate having a through-electrode on a base, and the micropores in the through-electrode are formed using an alkoxy run-based sol-gel solution. It has a configuration filled with objects.
The airtightness of the through electrode 44Aa constituting the produced through electrode substrate SD was evaluated using a vacuum spraying method, as in the first embodiment. As a result, the airtightness of the through electrode 34A was 5 × 10 ⁻¹⁰ [Pa · m ³ / sec] or less, and it was confirmed that the airtightness was improved.

In each of the above-described embodiments, nanometal ink manufactured by ULVAC, Inc. was used as the fluid containing conductive nanoparticles (for example, A14). Specifically, it is an ink (solid component concentration: 58 wt%, viscosity: 10 mPs · s, density: 1.7 g / cm ³ , solvent: tetradecane) using Ag particles having an average particle diameter of 3.8 nm as conductive particles. .
In order to carry out the present invention, a nano-sized conductive particle having a particle size of 10 nm or less or an ink paste containing the conductive particle is suitable. When the particle size of the conductive particles is 10 nm or less, the melting point becomes lower than the original melting point of the substance, and the sintering temperature can be lowered.

  However, in general, in an ink paste containing nano-sized conductive particles of 10 nm or less, a dispersing agent is adsorbed on the particle surface in order to express the dispersion stability of the particles. When the dispersant is removed and removed by baking, the particles are sintered, and as a result, conductivity is developed in the ink film.

For example, in an ink containing Ag particles having an average particle diameter of about 3 nm, the dispersant is desorbed at a baking temperature of 150 ° C. or higher, and the particles sinter, and is comparable to almost bulk Ag at a baking temperature of 200 ° C. or higher. Specific resistance value (about 3 μΩ · cm) can be obtained. After firing, softening does not occur unless the melting point of Ag is 962 ° C. or higher.
The same effect can be obtained even when all metals / alloys other than Ag and oxide conductors such as ITO are used.
Thereby, the problem of the difference between the glass and the thermal expansion coefficient can be solved.

In addition, by using nano-sized conductive particles, baking at a low temperature (500 ° C. or lower) is possible, and a heat-resistant resin such as polyimide (which can be used in ordinary photoresist or dry film depending on conditions) is used as the substrate surface. It can be used as a protective film or masking film. By using a protective film and masking film during filling of the conductive particles into the through holes and subsequent preliminary firing and main firing, the substrate surface can be kept clean and smooth, preventing scratches, This has the effect of aligning the height with the substrate surface. This eliminates the need for polishing after electrode formation.
Therefore, according to the present invention, it becomes possible to form an electrode on a substrate that has been subjected to uneven processing by eliminating the need for polishing after electrode formation.

In general, the adhesion between metal and glass is not high. Therefore, a glassy material such as an alkoxy run-based sol-gel film is provided as an adhesion layer on the side wall of the through hole in a calcined state, and then nano-sized conductive particles having a particle size of 10 nm or less or the conductive particles are provided. The adhesiveness between the glass substrate and the through electrode material can be further strengthened by filling the through hole with the ink paste that is contained and simultaneously firing it.
Therefore, according to the present invention, it is possible to stably manufacture a through electrode substrate including a through electrode having high airtightness.

  A low specific resistance value can be obtained by firing (sintering) nano-sized conductive particles having a particle size of 10 nm or less or an ink paste containing the conductive particles at a high temperature. In some cases, micropores (pores) are formed in the inside. In such a case, it is preferable to obtain a higher airtightness by filling the holes a plurality of times by impregnating the holes with a low viscosity ink containing the same conductive particles by vacuum and suction. Alternatively, high airtightness can also be obtained by impregnating a glassy material such as an alkoxylane-based sol-gel solution having a low viscosity by the same method (fourth embodiment).

<Example>
Example 1
As the glass substrate, borosilicate glass (Tempax: manufactured by Schott), thickness 0.3 mm, diameter 100 mm was used. Further, the glass substrate was polished in advance and used a flat and clean surface.
A through hole having a diameter of 0.2 mm and a pitch of 0.5 mm was formed on the glass substrate by blasting. At that time, the through holes were processed over the entire area of the glass substrate excluding the outer periphery of 10 mm. At this time, the dry film used for the blasting masking can be left without being peeled off and used as a protective film and a masking film in the post-processing. Furthermore, when used for a protective film / masking film, it is effective to use polyimide having high heat resistance.

A polyimide film was attached to the surface on the through side by blasting of the glass substrate in which the through holes were processed using a laminator.
Thereafter, an ink having conductive particles as Ag particles having an average particle diameter of 3.8 nm (solid component concentration: 58 wt%, viscosity: 10 mPs · s, density: 1.7 g / cm ³ , solvent: tetradecane) is provided with through holes. The substrate was dispensed in the form of a paddle with the opposite side of the polyimide film pasted up.
Next, by rotating (spinning) the substrate, excess ink was shaken off to fill the through holes with ink.

Next, pre-baking was performed at 70 ° C. for 30 minutes using a hot plate to volatilize the solvent.
Further, the substrate was placed on the hot plate again, and main baking was performed at 300 ° C., which is lower than the heat resistant temperature of polyimide, for 1 hour.
Next, after cooling the substrate, the polyimide film attached to the protection of the front and back surfaces was peeled off, washed with a glass substrate detergent / pure water, and finished by IPA vapor drying.
The airtightness of the through electrode of the substrate manufactured by the above process was measured by the vacuum spraying method as in the first embodiment, and showed a good value of ≦ 1 × 10 ⁻⁹ Pa · m ³ / sec. .

(Example 2)
As the glass substrate, borosilicate glass (Tempax: manufactured by Schott), thickness 0.3 mm, diameter 100 mm was used. Further, the glass substrate was polished in advance and used a flat and clean surface.
A recess having a depth of 50 μm was processed on the glass substrate by wet etching. The present invention is not limited to wet etching, and uneven processing may be performed by other methods such as machining or blasting.

Through holes having a diameter of 0.2 mm and a pitch of 0.5 mm were formed on the glass substrate with depressions using a blast method. At that time, the through holes were processed over the entire area excluding the substrate outer periphery of 10 mm.
At this time, the dry film used for the blasting masking can be left without being peeled off and used as a protective film and a masking film in the post-processing. Furthermore, when used for a protective film / masking film, it is effective to use polyimide having high heat resistance.

A polyimide film was attached to the surface on the through side by blasting of the glass substrate in which the through holes were processed using a laminator.
Thereafter, an ink (solid component concentration: 58 wt%, viscosity: 10 mPs · s, density: 1.7 g / cm ³ , solvent: tetradecane) using Ag particles having an average particle diameter of 3.8 nm as conductive particles is a substrate with through holes. The pad was dispensed in a paddle shape with the opposite side of the polyimide film pasted up.
Next, by rotating (spinning) the substrate, excess ink was shaken off to fill the through holes with ink.

Next, pre-baking was performed at 70 ° C. for 30 minutes using a hot plate to volatilize the solvent.
Further, the substrate was placed on the hot plate again, and main baking was performed at 300 ° C., which is lower than the heat resistant temperature of polyimide, for 1 hour.
Next, after cooling the substrate, the polyimide film attached to the protection of the front and back surfaces was peeled off, washed with a glass substrate detergent / pure water, and finished by IPA vapor drying.
The airtightness of the through electrode of the substrate manufactured by the above process was measured by the vacuum spraying method as in the first embodiment, and showed a good value of ≦ 1 × 10 ⁻⁹ Pa · m ³ / sec. .

(Example 3)
A substrate with a through hole was prepared in the same procedure as in Example 1.
A polyimide film was affixed to the surface on the penetrating side by blasting of the glass substrate in which the through holes were processed using a laminator.
A sol-gel solution (solid content: 10 wt%, viscosity: 2 mPa · s) based on TEOS of Si: B: Al: Na = 82: 12: 1: 4 so as to have a composition close to that of a glass substrate (Tempax). , Solvent: ethanol).
The sol-gel solution was dispensed in the form of a paddle with the opposite surface of the substrate with a through-hole attached to the polyimide film facing up.
Next, excess ink was shaken off by rotating (spinning) the substrate. Further, excess sol-gel solution inside the through hole was removed by nitrogen blowing.

Next, pre-baking was performed at 150 ° C. for 1 minute using a hot plate to volatilize the solvent.
In addition, when the skeleton formation is insufficient with only pre-baking, main baking may be added.
Thereafter, an ink (solid component concentration: 58 wt%, viscosity: 10 mPs · s, density: 1.7 g / cm ³ , solvent: tetradecane) using Ag particles having an average particle diameter of 3.8 nm as conductive particles is a substrate with through holes. The pad was dispensed in a paddle shape with the opposite side of the polyimide film pasted up.

Next, by rotating (spinning) the substrate, excess ink was shaken off to fill the through holes with ink.
Next, pre-baking was performed at 70 ° C. for 30 minutes using a hot plate to volatilize the solvent.
Further, the substrate was placed on the hot plate again, and main baking was performed at 300 ° C., which is lower than the heat resistant temperature of polyimide, for 1 hour.
Next, after cooling the substrate, the polyimide film attached to the protection of the front and back surfaces was peeled off, washed with a glass substrate detergent / pure water, and finished by IPA vapor drying.
The hermeticity of the through electrode of the substrate manufactured by the above process was measured by a helium spraying method and showed a good value of ≦ 1 × 10 ⁻⁹ Pa · m ³ / sec.

Example 4
In the substrate with through electrodes manufactured in Examples 1, 2, and 3, when the firing temperature is set to 300 ° C. or higher (for example, 350 ° C.), the specific resistance value is lowered, and there is an effect that a good value closer to the bulk is obtained. However, there are cases where pores grow.
Substrates produced at a firing temperature of 350 ° C. higher than those of Examples 1 and 2 were impregnated with the TEOS-based sol-gel solution used in Example 2 by using a vacuum pressure impregnation method.
A glass substrate is placed in a sealed container, evacuated to vacuum, and a sol-gel solution based on TEOS similar to that used in Example 3 as an impregnating solution is poured into the sealed container to a height at which the substrate is sufficiently immersed, and air is introduced. The inside of the container was pressurized and impregnated.

Next, after the impregnating solution was shaken off by spin drying, the sol-gel solution remaining on the surface of the glass substrate was wiped off with a cloth containing an organic solvent.
Next, pre-baking was performed at 150 ° C. for 1 minute using a hot plate to volatilize the solvent.
Further, the substrate was placed again on the hot plate and subjected to main baking at 350 ° C. for 1 hour.
Next, after cooling the substrate, the polyimide film attached to the protection of the front and back surfaces was peeled off, washed with a glass substrate detergent / pure water, and finished by IPA vapor drying.
The airtightness of the through electrode of the substrate produced by the above process was measured by the vacuum spraying method as in the first embodiment, and showed a good value of ≦ 5 × 10 ⁻¹⁰ Pa · m ³ / sec. .

From Examples 1 to 4 described above, the following points became clear.
(1) Since it can be fired at a low temperature of 500 ° C. or less, the difference in thermal expansion between the glass and the through electrode material can be small, so that various materials other than tungsten can be selected.
(2) Since it can be fired at a low temperature of 500 ° C. or lower, all processes including firing can be performed while protecting and masking the glass substrate surface with a heat resistant resin such as polyimide. As a result, a flat and clean surface can be obtained without polishing the through electrode formation.

(3) Furthermore, since it is not necessary to perform polishing after forming the through electrode, it is possible to easily form the through electrode even on a substrate having irregularities.
(4) Since firing is possible at a low temperature of 500 ° C. or lower, a through electrode can be formed even on a substrate where a semiconductor element or a MEMS element is formed and a process at a high temperature cannot be performed.
(5) According to the present invention, since no binder remains after firing, it is possible to stably produce a through electrode having a small specific resistance.

(6) A glassy material such as an alkoxy run-based sol-gel solution is provided on the side wall of the through hole as an adhesive layer, and is fired simultaneously with the conductive particles of the through electrode, thereby increasing the adhesion between the through electrode and the glass substrate. I can do things. Thereby, it is possible to prevent a gap between the through electrode and the glass substrate from being generated and to obtain high airtightness.
(7) According to the present invention, higher airtightness can be obtained by impregnating pores generated by sintering of conductive particles with a glassy material such as a low-viscosity alkoxysilane-based sol-gel film. Can do.

  The present invention is widely applicable to a method for manufacturing a through electrode substrate. Such a through electrode substrate is suitably used in the package field such as an interposer, the semiconductor field such as TSV, and the like.

  SA, SB, SC, SD Through electrode substrate, SGS fluid E, P Micropore (hole) 10, 20, 30, 40 Substrate, 11, 21, 31 Film, 12, 22, 32 Through hole, 13, 23, 33 Film, 14A, 24A, 34A, 44A (MA) Through electrode, 14 Fluid A, 24 Fluid B, 34 Fluid D, 37 Fluid C

Claims (6)

A first step of forming a through hole in the inside of the base with respect to one surface of the base made of flat glass; and
A second step of sealing the through hole on the other surface side by affixing a film-like sealing material to the other surface of the substrate that has undergone the first step;
The through-hole is filled with the fluid A containing conductive nanoparticles from one side of the substrate that has undergone the second step, and the conductive nanoparticles are sintered at a temperature lower than the heat resistance temperature of the sealing material. A third step of forming a through electrode by bonding;
Only including,
Further, a film is formed between the second step and the third step using a fluid C made of an alkoxy run-based sol-gel solution on the inner surface of the through hole formed in the second step. Process α,
A process for producing a through electrode substrate, comprising: A first step of forming a through hole in the inside of the base with respect to one surface of the base made of flat glass; and
A second step of sealing the through hole on the other surface side by affixing a film-like sealing material to the other surface of the substrate that has undergone the first step;
The through-hole is filled with the fluid A containing conductive nanoparticles from one side of the substrate that has undergone the second step, and the conductive nanoparticles are sintered at a temperature lower than the heat resistance temperature of the sealing material. A third step of forming a through electrode by bonding;
Including
Further, when micropores remain inside the through electrode, a process β for filling and repairing the micropores using a fluid C made of an alkoxylane-based sol-gel solution,
A process for producing a through electrode substrate, comprising: In the first step, using a substrate in which a recess is formed in advance on the other surface of the substrate;
The manufacturing method of the penetration electrode substrate according to claim 1 or 2 characterized by these. The step β
A step β1 of putting the base body through the third step into a sealed container and exhausting the inside of the sealed container;
The closed container inherent substrate having passed through the step .beta.1, while exhausting the inside of the sealed container, by introducing a moving object E flow into the interior of the sealed container, a state in which the base body is immersed in the fluid body E Step β2,
A step β3 of applying a pressure to the substrate that has undergone the step β2 via the fluid E;
Removing the substrate having undergone the step β3 from the sealed container and removing the fluid E adhering to the outer surface of the substrate;
A step β5 of providing a fourth heating means on the other surface side of the substrate that has undergone the step β4 to pre-bake the substrate;
Providing a fifth heating means on the other surface side of the substrate that has undergone the step β5, and baking the substrate to form a through electrode in which the micropores are repaired;
Removing the fifth heating means from the substrate that has undergone the step β6 and cleaning the substrate;
The manufacturing method of the penetration electrode substrate of Claim 2 comprised from these. A through electrode substrate comprising a through electrode on a substrate,
The through electrode Ri Do conductive nanoparticles provided in the through hole of the substrate,
A through electrode substrate, wherein an adhesive layer made of a coating formed from an alkoxy run-based sol-gel solution is disposed on an inner surface of the through hole . A through electrode substrate comprising a through electrode on a substrate,
The through electrode is composed of conductive nanoparticles provided in the through hole of the substrate,
The through-hole electrode substrate is characterized in that a fine hole existing in the through-hole electrode is filled with a formation using an alkoxylane-based sol-gel solution.

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