阅读说明：本技术 一种固态电容器及其制作方法 (Solid-state capacitor and manufacturing method thereof ) 是由 邢孟江 于 2021-09-30 设计创作，主要内容包括：本发明涉及一种固态电容器及其制造方法,属于电容器技术领域。本发明的电容器包括从上到下的的顶电极层、固态电解质层、阳极化氧化铝层和多孔铝电极层,多孔铝电极层为金属铝电极形成的单表面具有孔洞的电极结构,阳极化氧化铝层覆盖在孔洞内壁表面及所述多孔铝电极层的非光滑面,固态电解质层填充在所述孔洞内并向上延伸生长,本发明的电容具有容值大、性能稳定的特点,可适用于高性能集成电路设计制造以及各种电气自动化设备的应用制造。(The invention relates to a solid capacitor and a manufacturing method thereof, belonging to the technical field of capacitors. The capacitor comprises a top electrode layer, a solid electrolyte layer, an anodized aluminum oxide layer and a porous aluminum electrode layer from top to bottom, wherein the porous aluminum electrode layer is an electrode structure with a hole on a single surface formed by a metal aluminum electrode, the anodized aluminum oxide layer covers the inner wall surface of the hole and the non-smooth surface of the porous aluminum electrode layer, and the solid electrolyte layer is filled in the hole and extends upwards for growth.)

1. The solid-state capacitor is characterized by comprising a top electrode layer, a solid electrolyte, an anodized aluminum oxide layer and a porous aluminum electrode layer from top to bottom, wherein the porous aluminum electrode layer is an electrode structure formed by a metal aluminum electrode, holes with the porosity of 5% -90% are formed in a single surface of the electrode structure, the anodized aluminum oxide layer covers the inner wall surfaces of the holes and the non-smooth surface of the porous aluminum electrode layer, and the solid electrolyte is filled in the holes and extends upwards for growth.

2. A solid state capacitor according to claim 1, wherein: the holes are non-through holes which are regularly arranged or irregularly arranged.

3. A solid state capacitor according to claim 1, wherein: the shape of the hole is rectangular, circular, oval or irregular.

4. A solid state capacitor according to claim 1, wherein: the size of the hole is 50nm-500um, and the depth is 10nm-100 um.

5. A solid state capacitor according to claim 1, wherein: the thickness of the anodized aluminum oxide layer is 5nm-100 nm.

6. A solid state capacitor according to claim 1, wherein: the thickness of the top electrode layer is 50 nm-15 um.

7. A solid state capacitor according to claim 1, wherein: the solid electrolyte extends upwards to grow 50nm-500 nm.

8. A method of making a capacitor according to claims 1-7, wherein: comprises the following steps

(1) Forming a porous aluminum electrode layer with holes on a single surface by an etching or pressing method;

(2) connecting the smooth surface of the porous aluminum electrode layer with a positive electrode of a power supply, and connecting a negative electrode of the power supply with a carbon rod for anodic oxidation to obtain an anodized aluminum oxide layer;

(3) depositing the solid electrolyte to enable the holes to be filled and extend upwards for growth;

(4) the preparation of the top electrode layer is performed on the solid-state electrolyte by a physical additive manufacturing method.

9. The method of manufacturing according to claim 8, wherein: and the method also comprises the step of flattening the growing and depositing solid electrolyte.

Technical Field

The invention relates to a solid capacitor, and belongs to the technical field of capacitors.

Background

The capacitor plays an important role in designing and manufacturing electronic circuits and is an indispensable basic component. With the increasing level of circuit design and the increasing performance of circuits in the information age. The requirements for the characteristics of large capacitance value, high reliability, low cost and the like of the capacitor are continuously increased. The traditional aluminum oxide dielectric capacitor mostly adopts a planar structure, the capacitance value is low, and in addition, the aluminum oxide processing method is complex and the cost is high. The traditional electrolyte capacitor adopts liquid electrolyte which is not easy to package and has lower reliability.

Disclosure of Invention

The invention aims to overcome the defects of the existing capacitor and provides a solid capacitor with large capacitance value and stable performance.

The invention is realized by adopting the following technical scheme:

a solid-state capacitor comprises a top electrode layer, a solid-state electrolyte, an anodized aluminum oxide layer and a porous aluminum electrode layer from top to bottom, wherein the porous aluminum electrode layer is an electrode structure with holes in a single surface formed by a metal aluminum electrode, the anodized aluminum oxide layer covers the inner wall surface of the holes and the non-smooth surface of the porous aluminum electrode layer, and the solid-state electrolyte is filled in the holes and extends upwards for growth.

Furthermore, the holes are non-through holes which are regularly or irregularly arranged, and the other surface of the porous aluminum electrode layer keeps smooth and flat.

Further, the shape of the hole is rectangular, circular, oval or irregular.

Furthermore, the size of the holes is 50nm-500um, and the depth is 10nm-100 um.

Further, the porosity of the pores is 5% -90%.

Further, the thickness of the anodized aluminum oxide layer is 5nm to 100 nm.

Further, the solid electrolyte is extended and grown from 50nm to 500nm upward.

Further, the thickness of the top electrode layer is 50 nm-15 um.

Also provided is a method of making a solid state capacitor comprising the steps of

(1) Forming a porous aluminum electrode layer with holes on a single surface by an etching or pressing method;

(2) connecting the smooth surface of the porous aluminum electrode layer with a positive electrode of a power supply, and connecting a negative electrode of the power supply with a carbon rod for anodic oxidation to obtain an anodized aluminum oxide layer;

(3) depositing the solid electrolyte to enable the holes to be filled and extend upwards for growth;

(4) flattening the solid electrolyte which is grown and deposited;

(5) the preparation of the top electrode layer is performed on the solid-state electrolyte by a physical additive manufacturing method.

The invention has the beneficial effects that:

the capacitor provided by the invention adopts the porous aluminum electrode, so that the capacitance value of the capacitor can be greatly enhanced; the aluminum oxide medium is generated by anodization and oxidation, so that the inner walls of the holes of the aluminum electrode can be completely covered, and the electric leakage can be prevented; compared with liquid electrolyte, the solid electrolyte can reduce the packaging difficulty, enhance the reliability of the device and make the manufacturing method simpler. The capacitor with the structure has the characteristics of large capacitance value and stable performance, and is suitable for design and manufacture of high-performance integrated circuits and application and manufacture of various electric automation equipment.

Drawings

Fig. 1 is a schematic cross-sectional view of a capacitor of the present invention.

Description of reference numerals:

1 is a porous aluminum electrode layer, 2 is an anodized aluminum oxide layer, 3 is a solid electrolyte layer, and 4 is a top electrode layer.

Detailed Description

The invention will be further explained with reference to the drawings.

Example 1

This example shows a solid state capacitor, as shown in fig. 1, comprising a top electrode layer 4, a solid electrolyte layer 3, an anodized aluminum oxide layer 2 and a porous aluminum electrode layer 1 from top to bottom, wherein the porous aluminum electrode layer 1 is an electrode structure formed by a metal aluminum electrode and having holes on a single surface, the holes are non-through holes regularly or irregularly arranged, and the other surface of the porous aluminum electrode layer 1 is kept smooth and flat. The shape of the hole is rectangle, round, ellipse or irregular, the size of the hole is 50nm-500um, the depth is 10nm-100um, the porosity of the hole is 5% -90%, and the porosity is the percentage of the upper surface area of the hole to the upper surface area of the flat aluminum electrode.

And the anodized aluminum oxide layer 2 covers the inner wall surfaces of the holes and the whole surface of the porous aluminum electrode layer 1 except the smooth surface, and the thickness of the aluminum oxide layer is 5nm-100 nm. The anodized aluminum oxide layer 2 is prepared by an anodizing process.

The solid electrolyte layer 3 is located on the surface of the anodized alumina. For the holes with attached anodized alumina, the solid electrolyte layer 3 completely fills the holes. On the basis of the void filling, the solid electrolyte layer 3 is grown extending upward by 50nm to 500 nm. And polishing the upper surface of the solid electrolyte layer 3 to a flatness of 5nm to 200 nm. One side of the solid electrolyte layer 3 is in contact with the anodized aluminum oxide layer 2 and the other interface is in contact with the top electrode layer 4. Solid electrolytes include, but are not limited to, solid state species that are ionically conductive, or mixed ionically conductive, and are electrically conductive through ionic migration. The manufacturing method of the solid electrolyte layer 3 includes, but is not limited to, evaporation, magnetron sputtering, PECVD, molecular beam epitaxy and other physical and chemical reaction growth methods.

The top electrode layer 4 is located above the solid electrolyte layer 3. The manufacturing method includes, but is not limited to, physical additive manufacturing methods such as evaporation, magnetron sputtering, printing and the like. The electrode material includes but is not limited to copper, silver, gold, conductive paste and other metal materials with good conductive performance and non-metal materials. The thickness of the top electrode layer 4 is 50 nm-15 um.

The capacitor can be matched with packaging to lead out the electrode, and the packaging mode includes but is not limited to gold wire binding, solder balls, printed electrodes and the like. When the capacitor is connected with the conductor lead to lead out the electrode, the surface of the porous aluminum electrode layer 1 without the holes and the surface of the top electrode layer 4 which is not contacted with the solid electrolyte layer 3 are connected with the conductor lead.

Example 2

The present embodiment provides a method for manufacturing a solid state capacitor, the main method steps include porous aluminum electrode layer 1 preparation, anodized aluminum oxide layer 2 preparation, solid electrolyte deposition, solid electrolyte planarization treatment, and top electrode layer 4 preparation.

1) Production of the porous aluminum electrode layer 1. The hole electrode structure with holes on a single surface is formed by etching, pressing and other methods.

2) Anodizing the porous aluminum electrode layer 1 produces an aluminum oxide dielectric layer. The smooth surface of the porous aluminum electrode layer 1 is connected with the positive electrode of a power supply, and the negative electrode of the power supply is connected with a carbon rod. Starting a power supply, soaking one end of an aluminum electrode hole and a carbon rod in a citric acid/sodium citrate electrolyte solution, wherein the pH is 6.8-7.2, oxidizing an anode into two parts, (1) keeping the current density at 1.5-2 mA/cm2, increasing the voltage to 5-50V, and (2) keeping the voltage unchanged, and adjusting the current to reduce the index of the aluminum electrode to 5% -10% of the maximum value.

3) Solid electrolyte deposition. And depositing the solid electrolyte by physical and chemical reaction growth methods such as evaporation, magnetron sputtering, PECVD, molecular beam epitaxy and the like to fill the holes. On the basis of filling the holes, the solid electrolyte extends upwards to grow 50 nm-100 um.

4) And flattening the grown and deposited solid electrolyte. Preferably, the polishing treatment is performed so that the flatness is 5nm to 200 nm.

5) The top electrode layer 4 is grown. The top electrode is prepared by physical additive manufacturing methods such as evaporation, magnetron sputtering, printing and the like. The electrode material includes but is not limited to copper, silver, gold, conductive paste and other metal materials with good conductive performance and non-metal materials.

Example 3

The present embodiment discloses a solid state capacitor with a capacitance value of 600 nF/cm3 and a method of manufacturing the same. Wherein the capacitor comprises a porous aluminium electrode layer 1, an anodised aluminium oxide layer 2, a solid state electrolyte and a top electrode layer 4. The method comprises the steps of preparing a porous aluminum electrode layer 1, preparing anodic aluminum oxide, depositing solid electrolyte, flattening the solid electrolyte and preparing a top electrode layer 4.

Selecting an aluminum sheet with the thickness of 100um and the thickness of 1 mm by 1 mm as an aluminum electrode, selecting a photoresist on the aluminum electrode, and carrying out photoetching development by using a mask plate to determine the size of the hole to be 100 um. And etching the aluminum electrode by using a metal etching machine, wherein the etching gas is Cl2, BCl3, and the gas proportion is 1: and 2, controlling the pressure of the reaction cavity to be about 10 mtorr. The etched holes are 100um in size, 20 um in depth and 60% in porosity. The holes of the porous electrode are formed by being concentrated on one surface of the aluminum electrode, the other surface of the porous electrode is kept smooth and flat, and the aluminum electrode is not penetrated through the holes.

The porous aluminum electrode layer 1 and the top electrode layer 4 are respectively positioned at two ends of the capacitor, and anodized aluminum oxide and a solid electrolyte are sandwiched between the porous aluminum electrode layer and the top electrode layer. Wherein the thickness of the anodized aluminum oxide layer 2 is 50 nm. The smooth surface of the porous aluminum electrode layer 1 is connected with the positive electrode of a power supply, and the negative electrode of the power supply is connected with a carbon rod. The power supply was started and one end of the aluminum electrode hole and the carbon rod were immersed in citric acid/sodium citrate electrolyte solution at PH 6.8, first, the current density was maintained at 1.5 mA/cm2 and the voltage was increased to 30V. Then, the voltage is kept constant and the current is adjusted to exponentially decrease to 5% of the maximum value. An anodized aluminum oxide layer is obtained.

The solid electrolyte is located on the surface of the anodized alumina layer 2. The solid electrolyte is RbCu4Cl3I2, and is deposited on the porous aluminum electrode layer 1 attached with the aluminum oxide by a magnetron sputtering mode, and the growth is continued for 100nm on the basis of filling the holes. The upper surface of the solid electrolyte layer 3 was polished with chemical mechanical polishing to a flatness of 5 nm. A top electrode layer 4 is located on top of the solid-state electrolyte. The 100nm copper electrode was produced by thermal deposition.

Example 4

The present embodiment discloses a solid state capacitor with a capacitance value of 450 nF/cm3 and a method of manufacturing the same. Wherein the capacitor comprises a porous aluminium electrode layer 1, an anodised aluminium oxide layer 2, a solid state electrolyte and a top electrode layer 4. The process comprises the steps of preparing a porous aluminum electrode layer 1, preparing an anodized aluminum oxide layer 2, depositing a solid electrolyte, flattening the solid electrolyte and preparing a top electrode layer 4.

Metallizing a two-dimensional mesh-structured polymer material with the aperture of 200 um, the aperture depth of 50 um and the porosity of 90 percent, then removing the electroplating process, plating a layer of aluminum on the surface of the framework, and removing the internal polymer material through heat treatment to obtain the porous electrode, wherein the thickness of the aluminum electrode is 100um, and the size of the aluminum electrode is 0.5 mm x 0.5 mm. The holes of the porous electrode are formed by being concentrated on one surface of the aluminum electrode, the other surface of the porous electrode is kept smooth and flat, and the aluminum electrode is not penetrated through the holes.

The porous aluminum electrode layer 1 and the top electrode layer 4 are respectively positioned at two ends of the capacitor, and anodized aluminum oxide and a solid electrolyte are sandwiched between the porous aluminum electrode layer and the top electrode layer. Wherein the thickness of the anodized aluminum oxide layer 2 is 100 nm. The smooth surface of the porous aluminum electrode layer 1 is connected with the positive electrode of a power supply, and the negative electrode of the power supply is connected with a carbon rod. Starting a power supply, soaking one end of the hole of the aluminum electrode and the carbon rod in a citric acid/sodium citrate electrolyte solution with the pH of 7, firstly, keeping the current density at 2 mA/cm2, and increasing the voltage to 50V. Then, the voltage is kept constant and the current is adjusted to exponentially decrease to 10% of the maximum value. An anodized aluminum oxide layer is obtained.

The solid electrolyte is located on the surface of the anodized alumina layer 2. The solid electrolyte is Ag2S, and is deposited on the porous aluminum electrode layer 1 with aluminum oxide by thermal evaporation, and the pores are filled and grow for 50 nm. The upper surface of the solid electrolyte layer 3 was polished with chemical mechanical polishing to a flatness of 10 nm. A top electrode layer 4 is located on top of the solid-state electrolyte. The 200nm gold electrode was fabricated by magnetron sputtering.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.