JP2008252011A - Dielectric capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dielectric capacitor which can be stably produced and can suppress the diffusion of hydrogen atoms, from a mounting terminal to a dielectric layer during usage. <P>SOLUTION: An electrode 12, a dielectric layer 13, and the other electrode 14 are laminated, in this order, on a substrate 11, a first opening 15b for partially exposing a top surface 14T of the other electrode is formed on a first insulating layer 15 covering the other electrode, and a second opening 16b for partially exposing the top surface of the other electrode is formed on a second insulating layer 16 that covers the first insulating layer. The second opening has an opening dimension which is larger than that of the first opening, and the surface of a recessed portion H is covered with a conductive hydrogen barrier layer 17. Thus, more sure suppression of the diffusion of hydrogen atoms to the dielectric layer can be made, thereby suppressing degradation of the characteristics of the dielectric capacitor, for example, leakage current characteristics and dielectric characteristics. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a dielectric capacitor capable of stable production and having little deterioration in leakage current characteristics and dielectric characteristics during use.

Conventionally, various dielectric capacitors using a dielectric thin film as a dielectric layer have been proposed.
As shown in FIG. 9, Patent Document 1 discloses that a dielectric capacitor has a reaction prevention selected from Nb ₂ O ₅ , Ta ₂ O ₅ , ZrO ₂ , CeO ₂ , Y ₂ O ₃ or Hf ₂ O _3. It is proposed to prevent the deterioration of the characteristics of the dielectric capacitor due to the reaction between the SBT (dielectric) layer 103 and the SiO ₂ (interlayer insulating) layer 106 of the dielectric capacitor by covering with the film 105. Yes.
Further, Patent Document 1 discloses that a dielectric capacitor is covered with an oxide film and an insulating nitride film having an effect of preventing hydrogen diffusion thereon, thereby allowing oxygen defects in the dielectric layer or the ferroelectric layer of the dielectric capacitor. It has been proposed to prevent the deterioration of the characteristics of the dielectric capacitor due to.

As shown in FIG. 10, Patent Document 2 discloses that the inner wall of the through hole 213 continuously increases in diameter from the electrode layer 207 side toward the surface side of the protective film 209, and has a predetermined angle with respect to the electrode layer 207. Therefore, the corners projecting into the through hole 213 are not formed, and the coverage of the solder diffusion preventing layer 217 formed on the inner surface of the through hole 213 can be improved. As a result, the deterioration of reflow resistance due to solder diffusion can be suppressed, and even when the film thickness is reduced, the effect of preventing solder diffusion can be exerted. Therefore, the internal stress of the solder diffusion preventing layer 217 is further reduced, resulting from peeling and floating. It has been proposed to suppress deterioration of element reliability.
Further, in Patent Document 2, the coating strength of the film formed on the inner surface of the through hole 213 is improved, and the connection strength between the inner wall of the through hole 213 and the external terminal 211 that is filled and formed in the through hole 213. It has been proposed to prevent the peeling between the external terminal 211 formed by filling the through hole 213 and the electrode 207 to which the lower surface is bonded.

Japanese Patent Laid-Open No. 11-121704 JP 2001-284168 A

However, in the dielectric capacitor described in the former background art, the opening size of the SiO ₂ (interlayer insulating) layer 106 and the opening size of the Nb ₂ O ₅ (reaction prevention) layer 105 are equal, and therefore, at the bottom of the opening. The coverage of the upper electrode 104 by the extraction electrode (conductive hydrogen barrier film) 109 is lowered, and there is a problem that it is difficult to stably produce the dielectric layer without causing process deterioration.
Further, if the opening size is reduced in order to suppress the entry of hydrogen, there is a problem that the bonding strength is lowered and the reliability of the element is lowered.
Further, when the opening size is increased, there is a problem that the resistance deterioration characteristic is deteriorated due to the entry of hydrogen atoms into the SBT (dielectric) layer 103, and the long-term reliability of the element is lowered.
On the other hand, since the thin film electronic component described in the latter background art does not have a hydrogen barrier film, it suppresses diffusion of hydrogen atoms caused by hydrogen generated in the element formation process into the insulator layer 203 of the capacitor element. Therefore, there is a problem that the insulator layer 203 is deteriorated due to hydrogen. In addition, in the process of using the element, there is a problem that when the electric field is applied, hydrogen atoms diffuse from the mounting terminal to the dielectric layer and the capacitor element is deteriorated in resistance.

The present invention focuses on the above points, and its purpose is to suppress process deterioration of the dielectric layer and enable stable production, and to allow hydrogen atoms to diffuse from the mounting terminal to the dielectric layer during use. An object of the present invention is to provide a dielectric capacitor that can be suppressed.

  In order to achieve the above object, the dielectric capacitor according to the present invention includes: (1) one electrode and the other electrode on one main surface side of the substrate so as to face each other with a dielectric layer interposed therebetween. In a dielectric capacitor in which an electrode, a dielectric layer, and the other electrode are laminated in this order, a first opening that exposes a part of the upper surface of the other electrode is formed and the other electrode is covered A first insulating layer made of a hydrogen barrier layer and a second opening exposing a part of the surface of the first insulating layer in which the first opening is formed, and the first A second insulating layer covering the insulating layer, wherein an opening size of the second opening is larger than an opening size of the first opening, and the first opening A portion of the upper surface of the other electrode exposed by the first opening and the first opening A conductive hydrogen barrier layer covers the surface of the recess extending from a part of the surface of the formed first insulating layer to the surface of the second insulating layer in which the second opening is formed. It is characterized by that. (... hereinafter referred to as first problem solving means)

  In the dielectric capacitor of the present invention, (2) one electrode and the dielectric layer are arranged such that one electrode and the other electrode face each other with the dielectric layer interposed therebetween on one main surface side of the substrate. In the dielectric capacitor in which the plurality of electrodes and the other electrode are alternately stacked, a first opening that exposes a part of the upper surface of each of the other electrodes is formed and covers the other electrode. A first insulating layer made of a hydrogen barrier layer and a second opening exposing a part of the surface of the first insulating layer in which the first opening is formed are formed and the first A second insulating layer covering the insulating layer, wherein an opening size of the second opening is larger than an opening size of the first opening, and the first opening A portion of the upper surface of each other electrode exposed by The surface of the recess extending between a part of the surface of the first insulating layer in which the first opening is formed and the surface of the second insulating layer in which the second opening is formed is conductive hydrogen. It is covered with a barrier layer. (... hereinafter referred to as second problem solving means)

  In addition, one of the main embodiments of the present invention is characterized in that (3) the inner peripheral surface of the first opening and the inner peripheral surface of the second opening have inclined portions. (... hereinafter referred to as third problem solving means)

  According to another main embodiment of the present invention, (4) the first insulating layer covering the other electrode is provided with a plurality of openings, and the upper surface of the other electrode and the conductive barrier layer are provided. Are connected at a plurality of locations. (... hereinafter referred to as fourth problem solving means)

One of the embodiments of the present invention includes (5) a via conductor filled in a recess covered with the conductive hydrogen barrier layer, and a mounting terminal connected to the via conductor. And (... Hereinafter referred to as fifth problem solving means.)

Another embodiment of the present invention includes (6) a via conductor filled in a recess covered with the conductive hydrogen barrier layer, and a wiring layer connected to the via conductor. Features. (... Hereinafter referred to as sixth problem solving means)

The operation of the first problem solving means is as follows. That is, a first insulating layer formed of a hydrogen barrier layer that covers a part of the upper surface of the other electrode is formed so as to expose a part of the upper surface of the other electrode, and the first opening. And a second insulating layer formed on the first insulating layer, the second opening exposing a part of the surface of the first insulating layer formed with the second insulating layer covering the first insulating layer.
An opening size of the second opening is formed larger than an opening size of the first opening, and a part of the upper surface of the other electrode exposed by the first opening and the first The surface of the recess extending between a part of the surface of the first insulating layer in which the opening is formed and the surface of the second insulating layer in which the second opening is formed is a conductive hydrogen barrier layer. Because it is covered
In addition to an increase in the area where the first insulating layer made of the hydrogen barrier layer is formed on the electrode located at the bottom of the via conductor, the formation of the conductive hydrogen barrier layer is facilitated, thereby reducing the hydrogen generated in the process. The resulting diffusion of hydrogen atoms into the dielectric layer can be more reliably suppressed. In addition, diffusion of hydrogen atoms from the mounting terminal to the dielectric layer can be suppressed during use. Therefore, it is possible to provide a dielectric capacitor that can suppress deterioration of leakage current characteristics and dielectric characteristics.

The operation of the second problem solving means is as follows. That is, a first insulating layer formed of a hydrogen barrier layer that forms a first opening that exposes a part of the upper surface of each of the other electrodes and covers the other electrode; and A second insulating layer that is formed with a second opening that exposes a portion of the surface of the first insulating layer in which the opening is formed, and that covers the first insulating layer, and A part of the upper surface of each of the other electrodes exposed by the first opening, wherein the opening dimension of the second opening is larger than the opening dimension of the first opening. And the surface of the recess extending between a part of the surface of the first insulating layer in which the first opening is formed and the surface of the second insulating layer in which the second opening is formed is conductive. An electrode located at the bottom of the via conductor because it is covered with a hydrogen barrier layer In addition to an increase in the area on which the first insulating layer made of a hydrogen barrier layer is formed, the formation of a conductive hydrogen barrier film is facilitated, whereby a dielectric layer of hydrogen atoms resulting from hydrogen generated in the process It is possible to more reliably suppress diffusion into the water. In addition, diffusion of hydrogen atoms from the mounting terminal to the dielectric layer can be suppressed during use. For this reason, it is possible to provide a large-capacity dielectric capacitor capable of suppressing deterioration of leakage current characteristics and dielectric characteristics.

  The operation of the third problem solving means is as follows. That is, since the inner peripheral surface of the first opening portion and the inner peripheral surface of the second opening portion have inclined portions, the other electrode is electrically conductive with the other electrode at the bottom portion of the opening of the first insulating layer made of the hydrogen barrier layer. Stable contact with the reactive hydrogen barrier layer is obtained.

  The operation of the fourth problem solving means is as follows. That is, a plurality of openings are provided in the first insulating layer covering the other electrode, and the upper surface of the other electrode and the conductive barrier layer are connected at a plurality of locations. While suppressing deterioration of a layer, the tolerance of resistance deterioration improves.

  The operation of the fifth problem solving means is as follows. That is, a via conductor filled in the concave portion covered with the conductive hydrogen barrier layer and a mounting terminal connected to the via conductor are provided, so that the electric field moves from the mounting terminal on the anode side by an electric field. Of the hydrogen atoms, those that diffuse into the dielectric layer can be suppressed to a part.

  The operation of the sixth problem solving means is as follows. That is, since it has a via conductor filled in the recess covered with the conductive hydrogen barrier layer and a wiring layer connected to the via conductor, hydrogen atoms moving from the wiring layer on the anode side by an electric field Of these, those diffusing into the dielectric layer can be suppressed to a part.

The above and other objects, features, and advantages of the present invention will be apparent from the following detailed description and the accompanying drawings.

  According to the first problem-solving means of the present invention, it is possible to realize a dielectric capacitor that can be stably produced and has little deterioration of the dielectric layer during use. In addition, according to the second problem solving means of the present invention, it is possible to realize a large-capacity dielectric capacitor that can be stably produced and has little deterioration of the dielectric layer during use.

  Next, a first embodiment of the dielectric capacitor of the present invention will be described with reference to FIGS. FIG. 1 is an enlarged cross-sectional view of a main part for explaining the internal structure of the dielectric capacitor 10 of the first embodiment. FIG. 2 is a schematic diagram of an enlarged cross-sectional view of a main part for explaining the internal structure of the dielectric capacitor 10 of the present embodiment. FIG. 3 is a cross-sectional view showing the first half of an example of the manufacturing process of the dielectric capacitor 10 of the present embodiment, and FIG. 4 is a cross-sectional view showing the second half of the manufacturing process.

  As shown in FIG. 1, the dielectric capacitor 10 of the first embodiment is such that one electrode 12 and the other electrode 14 face each other across the dielectric layer 13 on one main surface side of a substrate 11. In addition, the one electrode 12, the dielectric layer 13, and the other electrode 14 are laminated in this order.

Specifically, in the dielectric capacitor 10 of the present embodiment, the first opening 15b that exposes a part of the upper surface 14T of the other electrode 14 is formed and the hydrogen covering the other electrode 14 is formed. A first insulating layer 15 made of a barrier layer and a second opening 16b that exposes a part of the surface of the first insulating layer 15 in which the first opening 15b is formed are formed. A second insulating layer 16 covering the first insulating layer 15, and the opening size of the second opening 16b is larger than the opening size of the first opening 15b, A part of the upper surface 14T of the other electrode 14 exposed by the first opening 15b, a part of the surface of the first insulating layer 15 in which the first opening 15b is formed, and the second The second insulation in which the opening 16b is formed Substantially conical recess H surface over the 16 surface is one that is coated with a conductive hydrogen barrier layer 17.

More specifically, a base layer AD such as TiOx is provided on one main surface side of the substrate 11 for the purpose of improving the adhesion with one electrode 12 to be formed next. On the base layer AD, the one electrode 12, the dielectric layer 13, and the other electrode 14 are laminated in this order. In addition, the formation area of the dielectric layer 13 is smaller than the formation area of the one electrode 12, and the formation area of the other electrode 14 is smaller than the formation area of the dielectric layer 13. Is formed.
A first insulating layer 15 made of a hydrogen barrier layer is formed so as to cover the other electrode 14, and the first insulating layer 15 has an upper surface 14 T of the other electrode 12. A first opening 15b that exposes a part is formed. An inclined portion 15c is provided on the inner peripheral surface of the first opening 15b. Further, the second insulating layer 15 is covered so as to eliminate a step caused by a laminated structure of the base layer AD, the one electrode 12, the dielectric layer 13, and the other electrode 14 while covering the first insulating layer 15. The second insulating layer 16 includes a part of the surface of the first insulating layer 15 in which the first opening 15b is formed and the other electrode. A second opening 16b that exposes a part of the upper surface 14T of 14 is formed. An inclined portion 16c is provided on the inner peripheral surface of the second opening 16b. Furthermore, the opening size of the second opening portion 16b is larger than the opening size of the first opening portion 15b, and the upper surface of the other electrode 14 exposed by the first opening portion 15b. 14T, a part of the surface of the first insulating layer 15 where the first opening 15b is formed, and a surface of the second insulating layer 16 where the second opening 16b is formed The surface of the recess H extending over is covered with the conductive hydrogen barrier layer 17. A via conductor 18 is filled in the recess H covered with the conductive hydrogen barrier layer 17. Further, on the exposed surface of the via conductor 18, a mounting terminal 19 made of a substantially spherical solder bump serving as an input / output terminal of the dielectric capacitor of the present embodiment is formed.

Next, the recess H will be described in more detail with reference to FIG. A base layer AD is provided on one main surface of the substrate 11, and one electrode 12, a dielectric layer 13, and the other electrode 14 are sequentially formed on the base layer AD. The first insulating layer 15 is covered except for a part of the upper surface 14T. The first insulating layer 15 is formed with a first opening 15b exposing a part of the upper surface 14T of the other electrode 14. An opening dimension c at the upper end of the first opening 15b formed in the first insulating layer 15 is formed larger than an opening dimension d at the lower end of the first opening 15b, and the first opening An inclined portion 15c is provided on the inner peripheral surface of the portion 15b. Also, the opening dimension a at the upper end of the second opening 16b formed in the second insulating layer 16 is formed larger than the opening dimension b at the lower end of the second opening 16b, and the second The opening 16b has an inclined portion 16c on the inner peripheral surface. Further, the recess H has an opening dimension d at the lower end of the first opening 15 b of the first insulating layer 15, an opening dimension c at the upper end of the first opening 15 b, and the second insulating layer 16. The opening dimension b at the lower end of the second opening 16b and the opening dimension a at the upper end of the second opening 16b are in a relation of a> b> c> d, and are formed in a substantially mortar shape. The opening dimensions a and b of the second opening 16b of the second insulating layer 16 are larger than the opening dimensions c and d of the first opening 15b of the first insulating layer 15. .

Next, an example of a manufacturing process of the dielectric capacitor 10 of the present embodiment will be described with reference to FIGS. First, as shown in FIG. 3A, a base layer AD such as TiOx is formed on one main surface of a substrate 11 such as silicon (Si), and one of Pt and the like is formed on the base layer AD. The electrode 12 is formed to a thickness of, for example, 250 nm by sputtering, for example. Next, as shown in FIG. 3B, a dielectric layer 13 such as BST (BaSrTiO ₃ ) is formed on the one electrode 12 by sputtering, for example, to a thickness of 150 nm. The other electrode 14 such as Pt is formed on the layer 13 by, for example, sputtering to a thickness of 250 nm, for example. Next, a resist film (not shown) is formed on the sample obtained above, and a resist pattern having a predetermined shape is formed by, for example, photolithography. Next, using the resist pattern as an etching mask, the other electrode 14 is patterned into a predetermined shape by dry etching using, for example, Ar / Cl ₂ gas under the conditions of an etching pressure of 1 Pa and an etching time of 5 minutes. Then, when the patterning is completed, the resist pattern is removed by ashing. Further, by repeating the resist film formation and ashing processes in the same manner as described above, the dielectric layer 13 and the one electrode 12 are sequentially patterned to obtain the sample shown in FIG. Next, as shown in FIG. 3D, a first insulating layer 15 made of a hydrogen barrier layer such as Al ₂ O ₃ is formed to a thickness of, for example, 100 nm so as to cover the sample. Next, as shown in FIG. 3E, for example, the first insulating layer 15 is patterned by the process of forming a resist film through ashing as described above, and the other electrode is formed on the first insulating layer 15. A first opening 15b exposing a part of the upper surface 14T of the fourteen and an opening exposing a part of the upper surface of the one electrode 12. 3F, a second insulating layer 16 such as BCB (benzocyclobutene) resin is formed on the sample obtained as described above. As shown in (G), the second insulating layer 16 is patterned by photolithography, for example, like the resist film, and a part of the surface of the first insulating layer 15 and the upper surface of the other electrode 14 are patterned. A second opening 16b exposing a part of 14T and an opening exposing a part of the surface of the first insulating layer 15 and a part of the upper surface of the one electrode 12 are formed. As shown in FIG. 4H, a part of the upper surface 14T of the other electrode 14, a part of the surface of the first insulating layer 15, and the second insulation are formed on the sample obtained above. So as to cover the surface of the recess H across the surface of the layer 16 For example, a conductive hydrogen barrier film 17 such as TiN is formed, and then a conductive metal such as Al is stacked on the conductive hydrogen barrier layer 17 and then a resist film is formed to an ashing process. By patterning the conductive hydrogen barrier layer 17 and the conductive metal layer, a sample in which the via conductor 18 made of the conductive metal is filled in the recess H is obtained as shown in FIG. Next, for example, solder plating is performed on the via conductor 18 and annealed at a predetermined temperature to form a mounting terminal 19 as shown in FIG.

Next, a preferred embodiment of the substrate 11 is as follows. That is, the substrate 11 is preferably selected from silicon, quartz, alumina, sapphire, glass and the like, obtained by cutting out from a base material, and having a flat surface. The thickness of the substrate 11 is preferably 0.02 μm to 500 μm. An underlayer AD such as TiOx is preferably formed on one main surface of the substrate 11 for the purpose of improving the adhesion with the next electrode 12 to be formed next. However, the present invention is not limited to this.

Next, a preferred embodiment of the one electrode 12 is as follows. That is, the one electrode 12 is preferably a noble metal such as Pt, Ir, or Ru, or a conductive oxide such as SrRuO _{3. In} the case of the noble metal, means such as vacuum deposition or sputtering is used on the substrate 11. Preferably, the conductive oxide is provided by means of sputtering, sol-gel, MOCVD, or the like. The thickness of the one electrode 12 is preferably 100 nm to 500 nm, for example. The processing of the one electrode 12 is preferably selected from means such as dry etching and wet etching.

Next, a preferred embodiment of the dielectric layer 13 is as follows. That is, the dielectric layer 13 is preferably BST (BaSrTiO ₃ ), PZT (PbZrTiO ₃ ), other perovskite structure oxides, and the like. It is preferred that The thickness of the dielectric layer 13 is preferably 50 nm to 500 nm, for example. The processing of the dielectric layer 13 is preferably selected from means such as dry etching or wet etching.

Next, a preferred embodiment of the other electrode 14 is as follows. That is, the other electrode 14 is preferably selected from the noble metals and conductive oxides shown in the one electrode 12. The thickness, formation method, and processing method of the other electrode 14 are preferably selected from those shown in the thickness, formation method, and processing method of the one electrode 12, respectively.

Next, a preferred embodiment of the first insulating layer 15 made of the hydrogen barrier layer is as follows. That is, as the first insulating layer 15, it is preferable to use a single layer selected from Al ₂ O ₃ , SiN, Ta ₂ O ₅ , SrTiO ₃ , etc. For example, one or a plurality of the types selected above may be laminated and used. The thickness of the first insulating layer 15 is preferably, for example, 50 nm to 3000 nm. The first insulating layer 15 is preferably selected from sputtering, sol-gel, MOCVD, or the like. The first insulating layer 15 is preferably selected from dry etching, wet etching, or the like.

Next, a preferred embodiment of the second insulating layer 16 is as follows. That is, the second insulating layer 16 can be selected from various inorganic insulating films and various organic insulating films, and examples of the inorganic insulating film include SiO ₂ and SiN. Examples of the organic insulating film include polyimide resin and BCB resin. The thickness of the second insulating layer is preferably 500 nm to 5000 nm, for example. The formation of the second insulating layer 16 can be selected from means such as sputtering, sol-gel, MOCVD, etc., in the inorganic insulating film, and in the organic insulating film, For example, it is preferable to form a coating film by applying the resin solution and then pattern the film by photolithography.

Next, a preferred embodiment of the conductive hydrogen barrier layer 17 is as follows. That is, the conductive hydrogen barrier layer 17 is preferably selected from TiN, TaN, TiSiN, TaSiN and other nitrides, SrRuO ₃ , IrO _{2 and} other oxides. The thickness of the conductive hydrogen barrier layer 17 is preferably 10 nm to 200 nm, for example. The conductive hydrogen barrier layer 17 is preferably selected from sputtering, MOCVD, or the like. Further, it is preferable that the conductive hydrogen barrier layer 17 is selected from dry etching, wet etching, or the like.

Next, a preferred embodiment of the via conductor 18 is as follows. That is, the via conductor 18 is preferably a conductive metal selected from Cu, Al and the like. The formation of the via conductor 18 is preferably selected from various methods such as vacuum vapor deposition, sputtering, plating, or the like, or those methods are continuously laminated.

Next, a preferred embodiment of the mounting terminal 19 is as follows. That is, the mounting terminal 19 can be selected from Au / Ni, solder bumps, or the like. The mounting terminals 19 are preferably formed by annealing at a predetermined temperature after forming the metal plating film.

In the first embodiment, the mounting terminal 19 is provided so as to be connected to the via conductor 18. However, the present invention is not limited to this, and for example, instead of the mounting terminal 19. A wiring layer may be provided.

In the first embodiment, the conductive hydrogen barrier layer 17, the via conductor 18 and the mounting terminal 19 connected to the other electrode 14 have been described. In the first embodiment, Similarly to the other electrode 14, the one electrode 12 is connected to the conductive hydrogen barrier layer, the via conductor, and the mounting terminal, but the description thereof is omitted.

In the first embodiment, the lead-out structure of the other electrode 14 and the lead-out structure of the one electrode 12 are the same. However, the present invention is not limited to this. A hole penetrating the substrate 11 in the thickness direction may be provided, a through-hole conductor may be filled in the hole, and the one electrode 12 may be drawn out to the other main surface side of the substrate 11 through the through-hole conductor. .

EXAMPLES Examples of the dielectric capacitor of this embodiment will be described below with reference to FIGS. First, as shown in FIG. 3A, a base layer AD having a thickness of 10 nm was formed by sputtering TiOx on one main surface of a silicon substrate 11 having a thickness of 400 μm. Next, one electrode 12 having a thickness of 250 nm was formed by sputtering Pt on the underlying layer AD. Next, as shown in FIG. 3B, a dielectric layer 13 having a thickness of 150 nm is formed on the one electrode 12 by sputtering BST (BaSrTiO ₃ ). The other electrode 14 having a thickness of 250 nm was formed by sputtering Pt. Next, after forming a resist film on the sample obtained above and forming a resist pattern having a predetermined shape by photolithography, the resist pattern is used as an etching mask and an etching pressure of 1 Pa, using Ar / Cl ₂ gas, The other electrode 14 was patterned into a predetermined shape by dry etching under the condition of an etching time of 5 minutes. Then, when the patterning was completed, the resist pattern was removed by ashing. Further, by repeating the resist film formation and ashing processes in the same manner as described above, the dielectric layer 13 and the one electrode 12 were sequentially patterned to obtain the sample shown in FIG. Next, as shown in FIG. 3D, Al ₂ O ₃ was sputtered to cover the sample to form a first insulating layer 15 made of a hydrogen barrier layer having a thickness of 100 nm. Next, as shown in FIG. 3E, the first insulating layer 15 is patterned by the process of forming a resist film through ashing in the same manner as described above, and the other electrode 14 is formed on the first insulating layer 15. The upper opening 14T that exposes a part of the upper surface 14T of the first electrode 12 is exposed with a substantially circular mortar-shaped first opening 15b having an opening dimension of 30 μm and an opening dimension of the lower end of 20 μm, and a part of the upper surface of the one electrode 12. And an opening. Next, as shown in FIG. 3F, a solution of BCB (benzocyclobutene) resin was applied on the sample obtained above and dried to form a second insulating layer 16. 4 (G), the second insulating layer 16 is patterned by photolithography in the same manner as the resist film, and a part of the surface of the first insulating layer 15 and the other are patterned. A substantially circular mortar-shaped second opening 16b having an upper end opening dimension of 100 μm and a lower end opening dimension of 80 μm exposing a part of the upper surface 14T of the electrode 14, and the surface of the first insulating layer 15; A part and an opening exposing a part of the upper surface of the one electrode 12 were formed, and then the other electrode 14 was formed on the sample obtained as shown in FIG. And part of the upper surface 14T of the first insulating layer The conductive hydrogen barrier film 17 having a thickness of 50 nm is formed by sputtering TiN so as to cover the surface of the substantially mortar-shaped recess H extending over a part of the surface of the second insulating layer 16 and the surface of the second insulating layer 16. Next, after depositing, for example, conductive metal Al on the conductive hydrogen barrier layer 17, the conductive hydrogen barrier layer 17 and the conductive metal layer are formed by a process of forming a resist film to ashing. 4 (I), a sample was obtained in which the via conductor 18 made of Al was filled in the substantially mortar-shaped recess H. Next, solder plating was performed on the via conductor 18. 4A and annealed at a predetermined temperature to form mounting terminals 19 made of solder bumps, as shown in Fig. 4J. The dielectric capacitor obtained in the above example was heated at 180 ° C. And Advantes Using a R6246 pA meter manufactured by KK, the change over time in leakage current was measured in a state where a DC voltage of +10 V was applied to the mounting terminal 19 connected to the other electrode 14, and the obtained results are shown in FIG. (Comparative example) Except that the opening size of the first opening of the first insulating layer and the opening size of the second opening of the second insulating layer are made equal to form a cylindrical recess. Was made in the same manner as in the previous example, and the change over time of the leakage current was measured in the same manner as described above, and the obtained result is shown in FIG. In addition, in the dielectric capacitor of the comparative example, a leakage current exceeding 1 × 10 ⁻⁷ A was measured from about 20 hours later, whereas in the dielectric capacitor of this example, when 100 hours elapsed. Big leak current increase until It was confirmed to be control.

Next, a second embodiment of the dielectric capacitor of the present invention will be described with reference to FIG. FIG. 5 is an enlarged cross-sectional view of a main part for explaining the internal structure of the dielectric capacitor 20 of the present embodiment.
As shown in FIG. 5, the dielectric capacitor 20 according to the second embodiment includes one electrode 22 and the other electrode 24 on one main surface side of the substrate 21, as in the first embodiment. The one electrode 22, the dielectric layer 23, and the other electrode 24 are laminated in this order so as to face each other across the dielectric layer 23.

Specifically, in the dielectric capacitor 20 of the present embodiment, the first opening 25b that exposes a part of the upper surface 24T of the other electrode 24 is formed and the hydrogen that covers the other electrode 24 is formed. A first insulating layer 25 made of a barrier layer, a part of the surface of the first insulating layer 25 in which the first opening 25b is formed, and a part of the upper surface 24T of the other electrode 24 are exposed. And a second insulating layer 26 that covers the first insulating layer 25 and has an opening dimension of the second opening 26b. The first opening 25b is formed larger than the opening size of the first electrode 25b and part of the upper surface 24T of the other electrode 24 exposed by the first opening 25b and the first opening 25b. Part of the surface of the insulating layer 25 and the second In which the surface of the concave portion H that extends between the said opening is formed the surface of the second insulating layer 26 is coated with a conductive hydrogen barrier layer 27.

The dielectric capacitor 20 of this embodiment is different from the dielectric capacitor 10 of the previous embodiment in that the wiring layer 29 leads out to an area not shown by the wiring layer 29 instead of the mounting terminals connected to the via conductors. Structure. Other configurations and operational effects are the same as in the first embodiment, and a description thereof will be omitted.

Next, a third embodiment of the dielectric capacitor of the present invention will be described with reference to FIG. FIG. 6 is an enlarged cross-sectional view of a main part for explaining the internal structure of the dielectric capacitor 30 of the present embodiment.

  As shown in FIG. 6, the dielectric capacitor 30 of the third embodiment has one electrode 32 and the other electrode 34 on one main surface side of the substrate 31, as in the first embodiment. The one electrode 32, the dielectric layer 33, and the other electrode 34 are laminated in this order so that they face each other across the dielectric layer 33.

Specifically, in the dielectric capacitor 30 of the present embodiment, the first opening 35b exposing a part of the upper surface 34T of the other electrode 34 is formed, and the hydrogen covering the other electrode 34 is formed. A first insulating layer 35 made of a barrier layer, a part of the surface of the first insulating layer 35 in which the first opening 35b is formed, and a part of the upper surface 34T of the other electrode 34 are exposed. And a second insulating layer 36 that covers the first insulating layer 35 and has an opening dimension of the second opening 36b. The first opening is formed larger than the opening size of 35b, and a part of the upper surface 34T of the other electrode 34 exposed by the first opening 35b and the first opening 35b are formed. Part of the surface of the insulating layer 35 and the second In which the surface of the concave portion H that extends between the said opening 36b is formed a surface of the second insulating layer 36 is coated with a conductive hydrogen barrier layer 37.

The dielectric capacitor 30 of this embodiment is different from the dielectric capacitor 10 of the previous embodiment in that a plurality of first openings are formed in the first insulating layer 35 made of a hydrogen barrier layer covering the other electrode 34. The portions 35b1 and 35b2 are provided, and the upper surface 34T of the other electrode 34 and the conductive hydrogen barrier layer 37 are connected at a plurality of locations.
Thereby, while suppressing the deterioration of the said connection location by a process, the tolerance of resistance deterioration improves.

Next, a fourth embodiment of the dielectric capacitor of the present invention will be described with reference to FIG. FIG. 7 is an enlarged cross-sectional view of a main part for explaining the internal structure of the dielectric capacitor 40 of the present embodiment.

  As shown in FIG. 7, the dielectric capacitor 40 of the fourth embodiment has one electrode 42a, 42c, dielectric layers 43a, 43b, 43c and the other electrode 44a, on one main surface side of the substrate 31. 44c are alternately stacked.

Specifically, in the dielectric capacitor 40 of the present embodiment, first openings 45b1 and 45b2 that expose portions of the upper surfaces 44T1 and 44T2 of the other electrodes 44a and 44c are formed, respectively, and A first insulating layer 45 comprising a hydrogen barrier layer covering the other electrodes 44a and 44c, a part of the surface of the first insulating layer 45 in which the first openings 45b1 and 45b2 are formed, and the A second opening 46b1 and 46b2 exposing a part of the upper surface of each of the other electrodes 44a and 44c, respectively, and a second insulating layer 46 covering the first insulating layer 45; And the opening dimensions of the second openings 46b1 and 46b2 are larger than the opening dimensions of the first openings 45b1 and 45b2, and the first opening 45 A part of the upper surface 44T1, 44T2 of each of the other electrodes 44a, 44c exposed by 1, 45b2 and a part of the surface of the first insulating layer 45 in which the first openings 45b1, 45b2 are formed. And the surface of the recess H covering the surface of the second insulating layer 46 in which the second openings 46b1 and 46b2 are formed is covered with the conductive hydrogen barrier layer 47.

The dielectric capacitor 40 of this embodiment is different from the dielectric capacitor 10 of the previous embodiment in that it includes a plurality of one electrodes 42a, 42c, dielectric layers 43a, 43b, 43c, and a plurality of other electrodes 44a, 44c, The one electrode 42 and the other electrode 44 are alternately stacked so as to sandwich the dielectric layer 43 therebetween. The one electrode 42a, 42c and the other electrode 44a, 44c are connected in parallel by the conductive hydrogen barrier layer.
As a result, the area where the first insulating layer made of the hydrogen barrier layer is formed on the electrode located at the bottom of the via conductor is increased, and the formation of the conductive hydrogen barrier film is facilitated. Therefore, the diffusion of hydrogen atoms into the dielectric layer due to hydrogen generated in the process can be more reliably suppressed. In addition, diffusion of hydrogen atoms from the mounting terminal to the dielectric layer can be suppressed during use. For this reason, it is possible to provide a large-capacity dielectric capacitor capable of suppressing deterioration of leakage current characteristics and dielectric characteristics. Other configurations and operational effects are the same as in the first embodiment, and a description thereof will be omitted.

  INDUSTRIAL APPLICABILITY According to the present invention, stable production is possible, and it is suitable for various thin, short, and small electronic devices using a dielectric capacitor that uses a dielectric layer with little deterioration during use.

It is a principal part expanded sectional view which shows the internal structure of 1st Embodiment of the dielectric capacitor of this invention. It is a schematic diagram of the principal part cross section shown for demonstrating the internal structure of 1st Embodiment of the dielectric capacitor of this invention. It is a principal part expanded sectional view which shows the first half part of an example of the manufacturing process of the dielectric capacitor of this embodiment. It is a principal part expanded sectional view which shows the second half part of an example of the manufacturing process of the dielectric capacitor of this embodiment. It is a principal part expanded sectional view which shows the internal structure of 2nd Embodiment of the dielectric capacitor of this invention. It is a principal part expanded sectional view which shows the internal structure of 3rd Embodiment of the dielectric capacitor of this invention. It is a principal part expanded sectional view which shows the internal structure of 4th Embodiment of the dielectric capacitor of this invention. It is a figure which shows the measurement result of the time-dependent change of the leakage current of the dielectric capacitor of the Example of this invention. It is sectional drawing which shows the dielectric capacitor of background art. It is sectional drawing which shows the thin film element of background art.

Explanation of symbols

10: Dielectric capacitor 11: Substrate 12: One electrode 13: Dielectric layer 14: The other electrode 14T: Upper surface 15: First insulating layer 15b: First opening 15c: Inclined portion 16: Second insulation Layer 16b: Second opening 16c: Inclined portion 17: Conductive hydrogen barrier layer 18: Via conductor 19: Mounting terminal 20: Dielectric capacitor 21: Substrate 22: One electrode 23: Dielectric layer 24: The other Electrode 24T: upper surface 25: first insulating layer 25b: first opening 25c: inclined portion 26: second insulating layer 26b: second opening 26c: inclined portion 27: conductive hydrogen barrier layer 28: via Conductor 29: Wiring layer 30: Dielectric capacitor 31: Substrate 32: One electrode 33: Dielectric layer 34: The other electrode 34T: Upper surface 35: First insulating layers 35b1, 35b2: First openings 35c1, 35c2 : Inclined part 36: No. Insulating layer 36b: second opening 36c: inclined portion 37: conductive hydrogen barrier layer 38: via conductor 39: mounting terminal 40: dielectric capacitor 41: substrates 42a, 42b: one electrode 43a, 43b, 43c : Dielectric layers 44a and 44b: Other electrodes 44T1 and 44T2: Upper surface 45: First insulating layers 45b1 and 45b2: First openings 45c1 and 45c2: Inclined portion 46: Second insulating layer 46b: Second Opening 46c: Inclined portion 47: Conductive hydrogen barrier layer 48: Via conductor 49: Mounting terminal a: Opening size b: Opening size c: Opening size d: Opening size AD: Underlayer

Claims (6)

A dielectric in which the one electrode, the dielectric layer, and the other electrode are laminated in this order so that one electrode and the other electrode face each other across the dielectric layer on one main surface side of the substrate In the capacitor, a first opening portion that exposes a part of the upper surface of the other electrode is formed, and a first insulating layer that is a hydrogen barrier layer covering the other electrode, and the first opening A second opening that exposes a portion of the surface of the first insulating layer on which the portion is formed and a second insulating layer that covers the first insulating layer, and An opening dimension of the second opening is formed larger than an opening dimension of the first opening, and a part of the upper surface of the other electrode exposed by the first opening and the first opening A part of the surface of the first insulating layer in which the opening is formed and the second opening are It made a second dielectric capacitor, wherein a surface of the recess extends between the surface of the insulating layer is coated with a conductive hydrogen barrier layer. A dielectric in which one electrode, a dielectric layer, and the other electrode are alternately stacked on one main surface side of the substrate so that one electrode and the other electrode face each other with the dielectric layer in between. In the body capacitor, a first insulating layer formed of a hydrogen barrier layer that forms a first opening that exposes a part of the upper surface of each of the other electrodes and covers the other electrode; and A second insulating layer that is formed with a second opening that exposes a portion of the surface of the first insulating layer in which the first opening is formed, and that covers the first insulating layer; The opening dimension of the second opening is formed larger than the opening dimension of the first opening, and the upper surface of each of the other electrodes exposed by the first opening is formed. A portion of the first opening formed with the first opening; A dielectric material characterized in that a surface of a concave portion covering a part of a surface of an edge layer and a surface of the second insulating layer in which the second opening is formed is covered with a conductive hydrogen barrier layer. Capacitor. 3. The dielectric capacitor according to claim 1, further comprising an inclined portion on an inner peripheral surface of the first opening and an inner peripheral surface of the second opening. The first insulating layer covering the other electrode is provided with a plurality of openings, and the upper surface of the other electrode and the conductive barrier layer are connected at a plurality of locations. Or the dielectric capacitor of 2. 5. The dielectric according to claim 1, further comprising: a via conductor filled in a recess covered with the conductive hydrogen barrier layer; and a mounting terminal connected to the via conductor. Body capacitor. 5. The dielectric according to claim 1, further comprising: a via conductor filled in a recess covered with the conductive hydrogen barrier layer; and a wiring layer connected to the via conductor. Capacitor.

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