WO2015160152A1 - Rectification diode and method for manufacturing same - Google Patents

Abstract

A rectification diode and a method for manufacturing the same are provided. The rectification diode comprises: an insulator layer including an insulator material; and a semiconductor layer located on the insulator layer and including an n-type Zno-based oxide semiconductor, wherein a rectification characteristic is exhibited between the insulator layer and the semiconductor layer. Thus, it is possible to provide a rectification diode having an improved electrical characteristic. Furthermore, when compared with conventional oxide diodes, the present invention offers a wider choice of materials since a P-type oxide semiconductor having many restrictions is replaced with the insulator layer. Thus, the range of adjusting electrical characteristic changes can also be extended.

Description

Rectifier Diode and Manufacturing Method

The present invention relates to a rectifying diode, and more particularly, to a rectifying diode using a rectifying effect occurring between an oxide semiconductor and an insulator and a method of manufacturing the same.

A rectifier diode is a semiconductor device having a property of flowing current in only one direction and not flowing in the opposite direction.

The rectifier diode is a PN junction diode composed of general N-type and P-type semiconductors, an MS diode composed of two layers of metal and semiconductor, or three layers of metal, insulator and semiconductor. There is a MIS Diode configured.

On the other hand, the oxide diode under study in the prior art consists of an N-type oxide semiconductor and a P-type oxide semiconductor, and has a rectifying ratio of about 10 ⁴ to 10 ⁶ .

In general, P-type oxide semiconductors are not easy to fabricate due to the inherent characteristics of oxide semiconductors, so the types of materials are very narrow. For this reason, diodes composed of N-type and P-type oxide semiconductors are subject to many restrictions in controlling electrical characteristics. In addition, the rectification ratio, which is very important in diode characteristics, is relatively low.

Therefore, there is a need to develop a new rectifier diode device that can broaden the control range of electrical characteristic changes, has an improved rectification ratio, and can be implemented as a transparent diode.

[Preceding technical literature]

[Patent Documents]

Republic of Korea Patent Publication No. 10-2011-0072231

The problem to be solved by the present invention is to provide a rectifying diode and a method of manufacturing the transparent and improved electrical characteristics.

One aspect of the present invention to achieve the above object provides a rectifying diode. The rectifier diode may include an insulator layer including an insulator material and an oxide semiconductor layer positioned on the insulator layer and including an n-type ZnO-based oxide semiconductor. At this time, it has a rectifying characteristic between the insulator layer and the oxide semiconductor layer.

In addition, the insulator layer may include a nitride or an oxide insulator. In addition, the n-type ZnO-based oxide semiconductor is characterized in that the IGZO.

The display device may further include a first electrode electrically connected to the insulator layer and a second electrode electrically connected to the oxide semiconductor layer.

In addition, the first electrode and the second electrode is characterized in that it comprises a metal having no rectifying characteristics with the oxide semiconductor layer. In this case, the first electrode and the second electrode may each independently include at least one selected from the group consisting of Al, Cu, Pt, Ti, In, Ga, Zn, Au, and Mo.

In addition, the first electrode and the second electrode is characterized in that the transparent electrode. At this time, the transparent electrode is characterized in that the ITO electrode.

In addition, the thickness ratio of the insulator layer and the oxide semiconductor layer may be 1: 1 to 1: 6.

In addition, the thickness of the insulator layer may be 10 nm to 200 nm.

Another aspect of the present invention to achieve the above object provides a method of manufacturing a rectifier diode. The rectifying diode manufacturing method includes forming a first electrode on a substrate, forming an insulator layer including an insulator material on the first electrode, and an oxide including an n-type ZnO-based oxide semiconductor on the insulator layer. The method may include forming a semiconductor layer and forming a second electrode on the oxide semiconductor layer. At this time, it has a rectification characteristic between an insulator layer and an oxide semiconductor layer.

The method may further include heat treating the substrate between the forming of the oxide semiconductor layer and the forming of the second electrode or after the forming of the second electrode.

The heat treatment of the substrate at this time is characterized in that performed at a temperature of 100 ℃ to 250 ℃.

In addition, the insulator layer may include a nitride or an oxide insulator. In addition, the n-type ZnO-based oxide semiconductor is characterized in that the IGZO.

According to the present invention, it is possible to provide a rectifying diode having improved electrical characteristics.

In addition, as the P-type oxide semiconductor, which is more restricted than the conventional oxide diode, is replaced with an insulator layer, the material selection can be made wider. Therefore, the control range of the electrical characteristic change can also be widened.

In addition, since the rectifying effect occurring at the interface between the oxide semiconductor layer and the insulator layer is used, there are almost no restrictions on the electrodes that can be used.

Moreover, since the transmittance | permeability in visible region is very high, it is applicable to a transparent element.

The technical effects of the present invention are not limited to those mentioned above, and other technical effects that are not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a cross-sectional view of a rectifying diode according to an embodiment of the present invention.

2 is a cross-sectional view of a rectifying diode according to another embodiment of the present invention.

3 to 8 are cross-sectional views illustrating a rectifying diode according to an embodiment of the present invention according to a process step.

FIG. 9 is a graph illustrating electrical characteristics of a diode and an insulator single layer including an oxide semiconductor and an insulator junction.

FIG. 10 is an energy band diagram illustrating a process of forming off-current of a diode formed of an oxide semiconductor and an insulator junction.

FIG. 11 is a graph illustrating CV characteristics of a diode formed of an oxide semiconductor and an insulator junction by 1 / C ² values and a voltage.

12 is an energy band diagram illustrating a process of forming on-current of a diode formed of an oxide semiconductor and an insulator junction.

FIG. 13 is a result of plotting I-V characteristics of a diode formed of an oxide semiconductor and an insulator junction through a P-N plot method.

FIG. 14 is a graph showing the electrical characteristics (I-V curve) of a diode composed of an oxide semiconductor and an insulator by Ln (I) values and voltages in order to obtain an ideal curve coefficient.

15 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 1. FIG.

16 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 2. FIG.

17 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 3. FIG.

18 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 4. FIG.

19 is a graph showing the current-voltage characteristics according to the thickness of the insulator layer in the rectifier diode according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

While the invention allows for various modifications and variations, specific embodiments thereof are illustrated by way of example in the drawings and will be described in detail below. However, it is not intended to be exhaustive or to limit the invention to the precise forms disclosed, but rather the invention includes all modifications, equivalents, and alternatives consistent with the spirit of the invention as defined by the claims.

When an element such as a layer, region or substrate is referred to as being on another component "on", it will be understood that it may be directly on another element or there may be an intermediate element in between. .

Although the terms first, second, etc. may be used to describe various elements, components, regions, layers, and / or regions, such elements, components, regions, layers, and / or regions It will be understood that it should not be limited by these terms.

In addition, the term C / B / A multilayer structure used in the present invention means a structure in which the B layer and the C layer are also located on the A layer.

1 is a cross-sectional view of a rectifying diode according to an embodiment of the present invention.

Referring to FIG. 1, a rectifier diode according to an embodiment of the present invention includes an insulator layer 300 and an oxide semiconductor layer 400 positioned on the insulator layer 300. In this case, the insulator layer 300 and the oxide semiconductor layer 400 may have a rectifying characteristic.

Insulator layer 300 may include an insulator material. For example, this insulator layer 300 may include a nitride or oxide insulator. For example, the insulator layer 300 may include silicon nitride (SiN _x ), silicon oxide (SiO ₂ ), or aluminum oxide (Al ₂ O ₃ ).

In addition, the thickness ratio of the insulator layer 300 and the oxide semiconductor layer 400 to be described later is preferably set to 1: 1 to 1: 6. If the thickness of the oxide semiconductor layer 400 is set to be greater than the thickness of the insulator layer 300 to be greater than 1: 6, it is difficult to form the entire oxide semiconductor layer 400 as a depletion layer. It may be difficult to implement.

In addition, the thickness of the insulator layer 300 may be 10 nm to 200 nm. For example, the thickness of the SiN _x insulator layer 300 may be set to 30 nm. If the thickness of the insulator layer 300 is set to 10 nm or less, it may not serve as an insulator. In addition, when the thickness of the insulator layer 300 is set to more than 200 nm, the resistance of the insulator layer 300 may be so high that a current may not flow.

The oxide semiconductor layer 400 is located on the insulator layer 300. The oxide semiconductor layer 400 may include an n-type ZnO-based oxide semiconductor. For example, the n-type ZnO-based oxide semiconductor may be InGaZnO (IGZO).

In addition, such an n-type ZnO-based oxide semiconductor may be amorphous.

According to the present invention, the rectifying characteristics appearing between the insulator layer 300 and the oxide semiconductor layer 400 are used.

For example, when a positive voltage is applied to the oxide semiconductor layer 400 and a negative voltage is applied to the insulator layer 300, no current flows, but a negative voltage is applied to the oxide semiconductor layer 400. When applied and a positive voltage is applied to the insulator layer 300, the current has a rectifying characteristic.

Therefore, according to the present invention, since the rectifying characteristics appearing between the insulator layer 300 and the oxide semiconductor layer 400 are used, the oxides having the rectifying characteristics can be used without using a P-type oxide semiconductor having a narrow material selection range. Diodes can be implemented.

In addition, the rectifier diode according to the present invention can widen the adjustment range of the electrical characteristic change, and has an improved rectification ratio.

2 is a cross-sectional view of a rectifying diode according to another embodiment of the present invention.

Referring to FIG. 2, the rectifying diode according to an embodiment of the present invention includes a substrate 100, a first electrode 200, an insulator layer 300, an oxide semiconductor layer 400, and a second electrode 500. can do.

The substrate 100 may select various materials as a supporting substrate. When the rectifier diode according to the present invention is applied to a transparent device, the substrate 100 may also use a material of a transparent material. For example, the substrate 100 may be a glass substrate.

The first electrode 200 is located on the substrate 100. Since the rectifying diode according to the present invention utilizes the rectifying characteristics appearing between the insulator layer 300 and the oxide semiconductor layer 400, there is no particular limitation of the material of the first electrode 200. Therefore, the first electrode 200 may use various metal materials.

For example, the first electrode 200 may include a metal having no rectifying characteristic with the oxide semiconductor layer 400. For example, the first electrode 200 may include at least one selected from the group consisting of Al, Cu, Pt, Ti, In, Ga, Zn, Au, and Mo.

As another example, the first electrode 200 may use a conductive material made of a transparent material. That is, the first electrode 200 may be a transparent electrode. For example, such a transparent electrode may be an ITO electrode.

On the other hand, unlike the present embodiment, as long as the first electrode 200 is electrically connected to the insulator layer 300 to be described later, its shape and position are not particularly limited.

The insulator layer 300 is located on the first electrode 200. The insulator layer 300 may include an insulator material. For example, this insulator layer 300 may include a nitride or oxide insulator. For example, the insulator layer 300 may include silicon nitride (SiN _x ), silicon oxide (SiO ₂ ), or aluminum oxide (Al ₂ O ₃ ).

The oxide semiconductor layer 400 is located on the insulator layer 300. The oxide semiconductor layer 400 may include an n-type ZnO-based oxide semiconductor. For example, the n-type ZnO-based oxide semiconductor may be InGaZnO (IGZO).

In addition, such an n-type ZnO-based oxide semiconductor may be amorphous.

Therefore, diode driving may be performed using the rectifying characteristics generated between the insulator layer 300 and the oxide semiconductor layer 400.

The second electrode 500 is located on the oxide semiconductor layer 400. Since the rectifying diode according to the present invention uses the rectifying characteristics appearing between the insulator layer 300 and the oxide semiconductor layer 400, the second electrode 500 also has no particular limitation as to the first electrode 200. Accordingly, the second electrode 500 may use various electrode materials.

For example, the second electrode 500 may include a metal having no rectifying characteristic with the oxide semiconductor layer 400. That is, a metal having no rectifying characteristic with the oxide semiconductor layer 400 may be selected as the material of the first electrode 200 and the second electrode 500. For example, the second electrode 500 may include at least one selected from the group consisting of Al, Cu, Pt, Ti, In, Ga, Zn, Au, and Mo.

For another example, the second electrode 500 may use a conductive material made of a transparent material. That is, the second electrode 500 may be a transparent electrode. For example, such a transparent electrode may be an ITO electrode. Therefore, since both the first electrode 200 and the second electrode 500 can use a transparent electrode, it is applicable to a transparent element.

Meanwhile, the second electrode 500 may be patterned. Meanwhile, unlike the present exemplary embodiment, the second electrode 500 is not particularly limited in form and position as long as the second electrode 500 is electrically connected to the oxide semiconductor layer 400.

3 to 8 are cross-sectional views illustrating a rectifying diode according to an embodiment of the present invention according to a process step.

Referring to FIG. 3, a substrate 100 is prepared. The substrate 100 may serve as a support substrate. For example, the substrate 100 may be a glass substrate or a polyethylene-naphthalate (PEN) substrate.

Preparing the substrate 100 may further include a cleaning step.

For example, the glass substrate may be cleaned using acetone and methanol for 10 minutes each in an ultrasonic cleaner.

Referring to FIG. 4, the first electrode 200 is formed on the substrate 100.

The first electrode 200 may use various electrode materials without particular limitation.

The first electrode 200 may be formed through a conventional deposition method. For example, physical vapor deposition, chemical vapor deposition, sputtering or solution processing are possible.

Referring to FIG. 5, an insulator layer 300 including an insulator material is formed on the first electrode 200.

For example, such insulator materials may include nitride or oxide insulators. For example, the insulator material may include silicon nitride (SiN _x ), silicon oxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ).

The insulator layer 300 may be formed using a physical vapor deposition method, a chemical vapor deposition method, a sputtering method or a solution process method.

Referring to FIG. 6, an oxide semiconductor layer 400 including an n-type ZnO-based oxide semiconductor may be formed on the insulator layer 300.

The oxide semiconductor layer 400 may include an n-type ZnO-based oxide semiconductor. For example, the n-type ZnO-based oxide semiconductor may be InGaZnO (IGZO).

The oxide semiconductor layer 400 may be formed using a physical vapor deposition method, a chemical vapor deposition method, a sputtering method or a solution process method.

Therefore, the insulator layer 300 and the oxide semiconductor layer 400 is characterized by having a rectifying characteristic.

Referring to FIG. 7, the substrate 100 on which the first electrode 200, the insulator layer 300, and the oxide semiconductor layer 400 are formed may be heat treated.

At this time, the heat treatment temperature may be 100 ℃ to 250 ℃. Therefore, there is an effect of improving rectification characteristics through such an annealing step.

In addition, the heat treatment of the substrate may be heat treatment in various atmospheres such as a vacuum atmosphere or a reducing atmosphere. For example, the substrate may be heat treated in a hydrogen (H ₂ ) atmosphere.

Meanwhile, the heat treatment step may be performed after the step of forming the second electrode 500.

Referring to FIG. 8, a second electrode 500 is formed on the oxide semiconductor layer 400.

Since the rectifying diode according to the present invention uses the rectifying characteristics appearing between the insulator layer 300 and the oxide semiconductor layer 400, the second electrode 200 also has no particular limitation as to the first electrode 200. Therefore, the second electrode 200 may use various electrode materials.

The second electrode 200 may be formed through a conventional deposition method. For example, physical vapor deposition, chemical vapor deposition, sputtering or solution processing are possible.

Hereinafter, the mechanism of rectification occurring between the insulator layer and the oxide semiconductor layer will be described.

Off-current forming process

FIG. 9 is a graph illustrating electrical characteristics of a diode and an insulator single layer including an oxide semiconductor and an insulator junction.

FIG. 9A is a graph measuring electrical characteristics of a diode (Mo / a-IGZO / SiNx / Mo) including an oxide semiconductor and an insulator junction. 9 (b) is a graph measuring electrical characteristics of an insulator single layer (Mo / SiNx / Mo).

9 (a) and 9 (b), the off-current of the diode using the oxide semiconductor and the insulator in FIG. 9 (a) shows a very low leakage current. This shows a current value of several thousand to tens of thousands times lower than the leakage current of the insulator of FIG.

FIG. 10 is an energy band diagram illustrating a process of forming off-current of a diode formed of an oxide semiconductor and an insulator junction.

Referring to FIG. 10, when a positive voltage, ie reverse bias, is applied to an upper electrode in an upper electrode / oxide semiconductor layer / insulator layer / lower electrode structure, an oxide semiconductor is depleted. The total resistance of the diode is increased by combining the resistance (RD) of the oxide semiconductor and the insulation (RI) of the oxide semiconductor, which is turned into a depletion layer. Therefore, a low current value is displayed.

FIG. 11 is a graph illustrating CV characteristics of a diode formed of an oxide semiconductor and an insulator junction by 1 / C ² values and a voltage.

Referring to FIG. 11, it can be seen that the oxide semiconductor (a-IGZO) has a good depletion as it increases linearly in a certain section (a line).

In other words, 1 / C ² and the voltage relationship are known as Mott-Schottky plot, and the inverse of the square value of the capacitor of the semiconductor increases linearly with the voltage to form the depletion region of the semiconductor. It can be seen that.

Therefore, it can be seen that the leakage current value thousands to tens of times lower than that of a single insulator is because the resistance of the insulator and the depletion layer of the oxide semiconductor acts as a series resistance. In addition, it can be seen that the oxide semiconductor layer is changed into a fully depleted layer (all of the oxide semiconductor layers are depletion layer) as the constant capacitance is shown at about 1.2 V or more.

<The process of forming on-current during the process of rectifying phenomenon>

Referring to FIG. 9 described above, the on-current flowing between the oxide semiconductor and the insulator of FIG. 9 (a) has a current value thousands of times higher than the leakage current of the single insulator of FIG. 9 (b).

12 is an energy band diagram illustrating a process of forming on-current of a diode formed of an oxide semiconductor and an insulator junction.

Referring to FIG. 12, in the upper electrode / oxide semiconductor layer / insulator layer / lower electrode structure, when a negative voltage, ie, a forward bias is applied to the upper electrode, an energy barrier existing at the interface between the oxide semiconductor and the insulator is formed. This is because there is a factor that lowers the energy barrier through which the current flows from the oxide semiconductor to the insulator between the interfaces. That is, at the interface between the oxide semiconductor and the insulator, electrons form on-current according to any reaction (b line) that can easily cross the insulator's energy barrier.

In relation to the factors that lower this energy barrier, it can be expected that the current flows through the Folwer-Nordheim mechanism through the P-N plot method.

FIG. 13 is a result of plotting I-V characteristics of a diode formed of an oxide semiconductor and an insulator junction through a P-N plot method.

Referring to FIG. 13, an electrical characteristic (I-V curve) of an oxide semiconductor and an insulator is represented by a relationship between ln (J / E2) and 1 / E (F-N plot). J is the current density and E is the electric field. As shown in FIG. 12, a linearly increasing section is formed in the F-N plot when crossing the energy barrier of the insulator.

In other words, the slope of the P-N plot at -0.233 V shows that the on-current current dominates the Fowler-Nordheim tunneling mechanism.

The Fowler-Nordheim tunneling mechanism is a mechanism in which an electric current flows through an energy barrier by applying a constant voltage when an energy barrier exists between two materials.

<Diode characteristics; Ideal factor factor>

FIG. 14 is a graph showing the electrical characteristics (I-V curve) of a diode composed of an oxide semiconductor and an insulator by Ln (I) values and voltages in order to obtain an ideal curve coefficient.

Referring to FIG. 14, the Si-based p-n junction has an ideal coefficient between 1 and 2. However, p-n junctions made of conventional oxide semiconductors are known to have ideal coefficients greater than two. It is known to have an ideal coefficient of greater than 2 due to recombination resulting from levels and defects present at the surface and interfaces, or tunneling resulting from deep levels.

The diode made of the oxide semiconductor and the insulator fabricated in the present invention has a value of 2.53 in FIG. 14, which is similar to the diodes made of the reported oxide semiconductor. Through this, it can be expected that the diode fabricated in the present invention is an oxide semiconductor type diode.

Production Example  One

A rectifying diode having a structure of [Mo / ZnO / Al ₂ O ₃ / Mo] according to an embodiment of the present invention was manufactured.

The first electrode is made of Mo. A 10 nm thick Al ₂ O ₃ insulator layer was deposited on the Mo electrode using chemical vapor deposition.

Then, a 30 nm thick ZnO oxide semiconductor layer was deposited on the Al ₂ O ₃ insulator layer by sputtering. The ZnO layer at this time is n-type.

Subsequently, a Mo electrode was deposited on the ZnO oxide semiconductor layer by a sputtering method as a second electrode.

Then, heat treatment was performed at 250 ° C. in a hydrogen atmosphere.

Production Example  2

A rectifying diode having a [Mo / IGZO / SiN _x / Mo] structure according to an embodiment of the present invention was manufactured.

The first electrode is made of Mo. On this Mo electrode, a 20 nm thick SiNx insulator layer was deposited using chemical vapor deposition.

Subsequently, a 60 nm thick IGZO oxide semiconductor layer sputtering method was deposited on the SiN _x insulator layer.

Next, the Mo electrode was deposited on the IGZO oxide semiconductor layer by the sputtering method as a second electrode.

Then, heat treatment was performed at 250 ° C. in a hydrogen atmosphere.

Production Example  3

A rectifying diode having a structure of [Mo / IGZO / Al ₂ O ₃ / Mo] according to an embodiment of the present invention was manufactured.

The first electrode is made of Mo. A 10 nm thick Al ₂ O ₃ insulator layer was deposited on the Mo electrode using chemical vapor deposition.

Next, a 30 nm thick IGZO oxide semiconductor layer was deposited on the Al ₂ O ₃ insulator layer by sputtering.

Next, the Mo electrode was deposited on the IGZO oxide semiconductor layer by the sputtering method as a second electrode.

Then, heat treatment was performed at 250 ° C. in a hydrogen atmosphere.

Production Example  4

A rectifying diode having an [ITO / IGZO / SiN _x / ITO] structure according to an embodiment of the present invention was manufactured.

The first electrode is composed of ITO. A 10 nm thick SiN _x insulator layer was deposited on this ITO electrode using chemical vapor deposition.

Next, a 30 nm thick IGZO oxide semiconductor layer was deposited on the SiN _x insulator layer by sputtering.

Then, an ITO electrode was deposited on the IGZO oxide semiconductor layer by the sputtering method as a second electrode.

Then, heat treatment was performed at 250 ° C. in a hydrogen atmosphere.

Experimental Example  One

The current-voltage characteristics of the rectifying diodes according to Preparation Examples 1 to 4 were measured.

15 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 1. FIG.

Referring to FIG. 15, it can be seen that rectification characteristics appear between the Al ₂ O ₃ layer and the n-type ZnO layer. At this time, it can be seen that the rectification ratio (Rectifyung ratio) characteristics of about 10 ⁴ to 10 ⁵ appears.

16 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 2. FIG. 17 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 3. FIG.

Referring to FIGS. 16 and 17, it can be seen that rectification characteristics are also shown when IGZO is used as the oxide semiconductor layer. Further, it can be seen that the rectification ratio characteristics of the rectifying diodes according to Preparation Example 2 and Preparation Example 3 are about 10 ⁸ to 10 ⁹ compared to the rectifying diode of Preparation Example 1.

18 is a graph showing the current-voltage characteristics of the rectifier diode according to Preparation Example 4. FIG.

Referring to FIG. 18, even when the first electrode and the second electrode are used as the ITO transparent electrode, it can be seen that the rectifying characteristics are shown. The rectification ratio at this time was measured to about 10 ⁸ to 10 ⁹ degree. Therefore, it can be seen that it is applicable to the transparent element.

Experimental Example  2

19 is a graph showing the current-voltage characteristics according to the thickness of the insulator layer in the rectifier diode according to the present invention. At this time, the rectifier diode has a [Mo / IGZO / SiN _x / Mo] structure.

Referring to FIG. 19, current-voltage characteristics were measured by setting the thicknesses of the SiN _x thin films to 3 nm, 10 nm, 20 nm, and 500 nm.

When the thickness of the SiN _x thin film is 3 nm, it can be seen that no rectification phenomenon occurs. This is because the SiN _x thin film becomes too thin to serve as an insulator.

In addition, when the thickness of the SiN _x thin film is 10 nm and 20 nm, it can be seen that the rectification phenomenon.

In addition, when the thickness of the SiN _x thin film is 500 nm, it can be seen that no current flows. This is because if the thickness of the SiN _x thin film becomes too thick, the resistance of the insulator becomes so high that no current can flow.

According to the present invention, it is possible to provide a rectifying diode having improved electrical characteristics.

In addition, as the P-type oxide semiconductor, which is more restricted than the conventional oxide diode, is replaced with an insulator layer, the material selection can be made wider. Therefore, the control range of the electrical characteristic change can also be widened.

In addition, since the rectifying effect occurring at the interface between the oxide semiconductor layer and the insulator layer is used, there are almost no restrictions on the electrodes that can be used.

Moreover, since the transmittance | permeability in visible region is very high, it is applicable to a transparent element.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples for clarity and are not intended to limit the scope of the present invention. It is apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be carried out in addition to the embodiments disclosed herein.

[Description of the code]

100 substrate 200 first electrode

300: insulator layer 400: oxide semiconductor layer

500: second electrode

Claims (15)

1. An insulator layer comprising an insulator material; And

   An oxide semiconductor layer disposed on the insulator layer and including an n-type ZnO-based oxide semiconductor;

   And a rectifying characteristic between the insulator layer and the oxide semiconductor layer.
2. The method of claim 1,

   And the insulator layer comprises a nitride or oxide insulator.
3. The method of claim 1,

   The n-type ZnO-based oxide semiconductor is a rectifier diode, characterized in that the IGZO.
4. The method of claim 1,

   A first electrode electrically connected to the insulator layer; And

   And a second electrode electrically connected to the oxide semiconductor layer.
5. The method of claim 4, wherein

   The rectifying diode of claim 1, wherein the first electrode and the second electrode include a metal having no rectifying characteristic with the oxide semiconductor layer.
6. The method of claim 5,

   And the first electrode and the second electrode each independently include at least one selected from the group consisting of Al, Cu, Pt, Ti, In, Ga, Zn, Au, and Mo.
7. The method of claim 4, wherein

   And the first electrode and the second electrode are transparent electrodes.
8. The method of claim 7, wherein

   The rectifying diode, characterized in that the transparent electrode is an ITO electrode.
9. The method of claim 1,

   The thickness ratio of the insulator layer and the oxide semiconductor layer is 1: 1 to 1: 6.
10. The method of claim 1,

    The rectifier diode has a thickness of 10 nm to 200 nm.
11. Forming a first electrode on the substrate;

    Forming an insulator layer comprising an insulator material on the first electrode;

    Forming an oxide semiconductor layer including an n-type ZnO-based oxide semiconductor on the insulator layer; And

    Forming a second electrode on the oxide semiconductor layer;

    And a rectification characteristic between the insulator layer and the oxide semiconductor layer.
12. The method of claim 11,

    Between the forming of the oxide semiconductor layer and the forming of the second electrode or after the forming of the second electrode,

    Rectifying a diode manufacturing method further comprising the step of heat-treating the substrate.
13. The method of claim 12,

    The step of heat-treating the substrate is a rectification diode manufacturing method, characterized in that performed at a temperature of 100 ℃ to 250 ℃.
14. The method of claim 11,

    The insulator layer comprises a nitride or oxide insulator manufacturing method.
15. The method of claim 11,

    The n-type ZnO-based oxide semiconductor is a rectification diode manufacturing method, characterized in that the IGZO.

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