KR101306022B1 - Functionality thin film and method for laminating functionality thin film - Google Patents

Abstract

A functional thin film is disclosed, and the functional thin film includes a transparent substrate, a transparent semiconductor layer formed on the transparent substrate, the transparent semiconductor layer including an oxide maintaining a transparent state in a visible light region, and an insulating protective film formed on the transparent semiconductor layer. However, the sheet resistance of the transparent semiconductor layer is 10MΩ / □ ~ 100MΩ / □.

Description

FUNCTIONALITY THIN FILM AND METHOD FOR LAMINATING FUNCTIONALITY THIN FILM}

The present invention relates to a functional thin film and a method for stacking a functional thin film.

With the development of the mobile display-related industry using touch screens such as smartphones and pads, new demands and researches for the next generation touch screens are progressing. In particular, research is being conducted on electric sensitive touch screens that can recognize a user's tactile sense by forming an electric field on the screen as well as a function of inputting data on the touch screen.

U.S. Patent Publication No. US2011 / 0109588 (name of the invention: TACTILE STIMULATION APPARATUS HAVING A COMPOSITE SECTION COMPRISING A SEMICONDUCTING MATERIAL) discloses an electrosensitive touch screen structure, which creates an electrosensitive touch screen, Use a tight structure.

1 is a view for explaining an electrical stimulation detection-related device. Referring to FIG. 1, it is an electrosensitive screen composed of a semiconductor layer having an electrode connected to the bottom thereof and an insulating layer stacked on the semiconductor layer. This device uses an electrostatic charge, so there is an insulating layer made of insulator. When the surface of the insulating layer is touched, the electrostatic charge is transferred to the semiconductor layer, and the electrostatic charge is transferred to the stimulus signal of the capacitive touch screen positioned under the electrosensitive screen. The capacitive touch screen similarly recognizes a change in capacitance to perform a touch screen operation. However, as this is done, charges accumulate in the insulating layer, which may degrade the function of the electrosensitive screen.

On the other hand, the electro-sensitive screen includes a semiconductor layer, the capacitance of the semiconductor layer is so small that the capacitive touch screen does not operate when the conductor level. Conversely, if the resistance is too high to reach the insulator level, the electrosensitive screen will not work. Therefore, there is a need to maintain the resistance of the semiconductor layer at an appropriate level.

In addition, since touch screens are mainly used for displays, all substrates and thin films used in electrosensitive screens must be transparent to visible light.

The thin film that satisfies this resistance level and guarantees transparency in the visible light region has difficulty in manufacturing.

The present invention was created to solve the problems described above, to prevent the accumulation of charge in the insulating layer to maintain the function of the electric-sensitive screen, while satisfying the appropriate resistance level, while the capacitive touch screen is easily operated An electrically sensitive screen also provides a method for stacking functional thin films and transparent semiconductor layers that facilitates operation and ensures transparency in the visible region.

As a technical means for achieving the above technical problem, the functional thin film according to the first aspect of the present application is a transparent substrate, a transparent semiconductor layer formed on the transparent substrate, including a oxide to maintain a transparent state in the visible light region, And an insulating protective film formed on the transparent semiconductor layer, wherein the sheet resistance of the transparent semiconductor layer may be 10 MΩ / □ to 100 MΩ / □.

Functional thin film stacking method according to the second aspect of the present invention comprises the steps of forming a transparent semiconductor layer through a sputtering method or a chemical vapor deposition method on a transparent substrate, adjusting the resistance through the n-type doping to the formed transparent semiconductor layer, And forming an insulating protective film with SiOx on the transparent semiconductor layer, wherein the sheet resistance of the transparent semiconductor layer may be 10MΩ / □ to 100MΩ / □.

According to the present invention, a transparent semiconductor layer containing an oxide that maintains a transparent state in the visible light region is included in a state where the sheet resistance is 10 M □ / □ to 100 MΩ / □, thereby making it transparent to the visible light region and operating a capacitive touch screen. The requirements for and the requirements for electrically sensitive screens can be met simultaneously.

According to the present invention, by forming a transparent semiconductor layer through a sputtering method or a chemical vapor deposition method, it is possible to form a high quality transparent semiconductor layer at a low temperature.

In addition, the n-type doping provides a sheet resistance of 10M □ / □ to 100MΩ / □, which is transparent to the visible region and simultaneously meets the requirements for capacitive touchscreen operation and the requirements for electrosensitive screens. Can be.

1 is a view for explaining a conventional electrical stimulation detection related device.
2 is a structural diagram of a functional thin film according to an embodiment of the present invention.
3 is a flowchart illustrating a functional thin film stacking method according to an embodiment of the present invention.
4 is a schematic conceptual view of a horizontally opposed sputtering apparatus according to an embodiment of the present invention.
5 is a schematic conceptual view of a PECVD apparatus to which an auxiliary electrode according to an exemplary embodiment of the present invention is applied.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

2 is a structural diagram of a functional thin film according to an embodiment of the present invention.

The functional thin film 100 according to the embodiment of the present invention includes a transparent substrate 10. For example, the transparent substrate 10 may use a glass substrate. In addition, although not shown, an insulator layer and an electrode layer may be added to the lower portion of the transparent substrate 10 as a configuration for sensing a touch.

Referring to FIG. 2, the functional thin film 100 is formed on the transparent substrate 10 and includes a transparent semiconductor layer 20 including an oxide that maintains a transparent state in the visible light region. In addition, the sheet resistance of the transparent semiconductor layer 20 may be 10MΩ / □ ~ 100MΩ / □.

For example, the oxides maintaining the transparent state in the visible light region included in the transparent semiconductor layer 20 may be ZnO and SnO 2. Oxides such as ZnO and SnO2 have a bandgap of 3 eV or more and can pass through a wavelength of 380 to 780 nm to which the visible region belongs, and thus are transparent in the visible region. In addition to ZnO and SnO 2, an oxide having a band gap capable of passing a visible light region can be used.

As described above, the transparent semiconductor layer 20 including oxides such as ZnO and SnO 2 must have an appropriate sheet resistance to satisfy both the requirements for the capacitive touch screen operation and the requirements for the electrosensitive screen. The sheet resistance that satisfies these requirements simultaneously may be, for example, 10 MΩ / □ to 100 MΩ / □.

Since ZnO and SnO2 have a very large resistance in a pure material state, a resistance of 10MΩ / □ to 100MΩ / □ can be satisfied by using a resistance control method through doping. For example, when using SnO 2, doping is performed using fluorine (F). In the case of ZnO, for example, n-type doping is performed using one of aluminum (Al), gallium (Ga), and boron (B). Hydrogen (H) can be used as a reactant when doping to ensure resistance and visible light transmittance in a desired area at the same time. Accordingly, the oxide of the transparent semiconductor layer 20 is SnO 2, n-type doping using fluorine, and the oxide of the transparent semiconductor layer 20 is ZnO, and n-type doping is performed using one of aluminum, gallium, and boron. .

As a method of controlling the resistance, there is a method of controlling the resistance by controlling the degree of crystallization by a method of oxygen deficiency, not a control through doping. Increasing the degree of crystallinity increases the transparency of the thin film, increases the mobility of the hole and also increases the number of holes can lower the resistance. In addition, as described above, the transparency of the visible light region should be ensured due to the characteristics of the touch screen that is used for display, and the transparency of the thin film itself may be improved by controlling the crystallinity.

However, in the case of ZnO, when the resistance is controlled by adjusting the crystallinity, it is difficult to maintain transparency in the visible light region. For example, a phenomenon that looks yellow or green may appear.

Therefore, the crystallinity can be controlled to maintain transparency in the visible light region, and at the same time, a thin film having a desired transparency and resistance can be manufactured through n-type doping using hydrogen with the aforementioned reactor.

In addition, the transparent semiconductor layer 20 may have a thickness of about 10 nm to about 100 nm. The reason for having such a thin film thickness is because of transparency and color control due to interference with the insulating protective film 30 to be described later. When two thin films having different refractive indices are stacked, constructive interference and extinction interference are caused by the change of wavelength due to the interference of light, so that even a transparent thin film may have a low transparency or a specific color.

The refractive index of the insulating protective film 30 to be described later is about 1.5, and in the case of ZnO, the refractive index of the insulating protective film 30 is greater than that. In order to control the transparency and color, the transparent semiconductor layer 20 has a thin film thickness of about 10 nm to about 100 nm. In addition, the insulating protective film 30 to be described later has a thin film thickness between 500 nm and 1 μm. The transparent substrate 10 can be 0.7 mm in thickness. Anti-reflection coating can be used to increase the transparency. By way of example, when ZnO is coated on the transparent substrate 10, the refractive index is larger than that of the transparent substrate 10 and thus has a thickness of approximately λ / 2. Since the insulating protective film 30, which will be described later, has a refractive index of 1.45 to 1.5, when the thickness is λ / 4, an optimal transmittance may be secured at a corresponding wavelength λ.

Also, referring to FIG. 2, the functional thin film 100 includes an insulating protective film 30 formed on the transparent semiconductor layer 20.

The insulating protective film 30 may be SiOX, for example.

Also, referring to FIG. 2, the functional thin film 100 may include an anti-fingerprint film 40 formed on the insulating protective film 30.

As described above, the fingerprint is buried due to the characteristics of the touch screen that the finger is in direct contact with the surface can be a fingerprint prevention coating to prevent this. In addition, when charge is accumulated in the insulating protective film 30, the function is reduced as an electrosensitive touch screen. By forming the anti-fingerprint film 40, charges may be prevented from accumulating in the insulating protective film 30.

Hereinafter, a method for laminating a transparent semiconductor layer according to an embodiment of the present invention will be described.

For reference, the functional thin film stacking method according to an embodiment of the present invention relates to a method of stacking a functional thin film according to an embodiment of the present invention, and the configuration described in the functional thin film according to the embodiment of the present invention Like reference numerals refer to like elements, and descriptions thereof will be briefly or omitted.

3 is a flowchart illustrating a functional thin film stacking method according to an embodiment of the present invention.

Referring to FIG. 3, in the functional thin film stacking method according to an embodiment of the present invention, a transparent semiconductor layer 20 is formed on a transparent substrate 10 through a sputtering method or a chemical vapor deposition method (CVD). In step S210, the sheet resistance of the transparent semiconductor layer 20 may be 10 MΩ / □ to 100 MΩ / □.

The reason why the sheet resistance of the transparent semiconductor layer 20 is 10 MΩ / □ to 100 MΩ / □ is as described above, which is transparent to the visible region, and the requirements for the capacitive touch screen operation and the requirements for the electrosensitive screen. To satisfy at the same time.

Methods of making the transparent semiconductor layer 20 are largely wet and dry. In an exemplary embodiment of the present invention, the transparent semiconductor layer 20 is formed using a sputtering method or a chemical vapor deposition method as one of the PVD methods in a dry method. When forming the transparent semiconductor layer 20 using a sputtering method or a chemical vapor deposition method, it is possible to control the resistance through doping which will be described later.

In the synthesis of ZnO or SnO2 thin film by sputtering method, in general sputtering method, oxygen ions are accelerated to the substrate, which adversely affects the formation of high quality thin film. For this reason, defect control should be performed by heating a board | substrate to high temperature (200 degreeC or more). Then, when doping hydrogen into the reactor for doping can be n-type doping. The doping concentration can be controlled by adjusting the inflow of hydrogen gas, and thus the resistance of the thin film can be controlled. In the sputtering process, the substrate temperature, the process pressure, the electrical energy given to the target, and the hydrogen inflow rate act as factors for determining the formation of high quality thin film.

4 and 5 to be described below are for explaining the transparent semiconductor layer forming step (S210) and the resistance adjusting step (S220) of FIG.

4 is a conceptual diagram of a horizontally opposed sputtering apparatus according to an embodiment of the present invention.

Looking in detail at the facing opposing sputtering method, an example substrate may be located above or below the device. In this case, since radicals having strong energy from the target do not directly affect the substrate, a high quality thin film may be obtained even at a low temperature. In addition, when the hydrogen inflow is controlled, a high quality transparent semiconductor layer 20 can be formed at a low temperature.

Factors affecting the crystallinity of the thin film include the temperature of the substrate and the energy of radicals incident on the substrate. In particular, in the case of an oxide such as ZnO, a large amount of damage is caused to thin film synthesis by oxygen ions having high kinetic energy. Eliminating these radical damage is a key factor in increasing crystallinity at low temperatures.

As a method for reducing damage caused by such radicals, the above-described horizontally opposed target sputtering method is used. Specifically, for example, in the horizontally opposed target sputtering method, the substrate is positioned perpendicular to the electrode, thereby minimizing the impact of radicals having high energy. In this case, the factor affecting the degree of crystallinity should be within 15 cm as the distance between the horizontal opposing targets, and the substrate must be within 10 cm from the electrode to receive the energy required for crystallization.

5 is a schematic conceptual view of a PECVD apparatus to which an auxiliary electrode according to an exemplary embodiment of the present invention is applied.

The chemical vapor deposition method may be used among the methods of making the above-mentioned transparent semiconductor layer 20. For example, when forming a ZnO thin film using a general chemical vapor deposition method, dimethyl zinc (DMZ) or diethyl zinc (DEZ) is used as a precursor, which is a source having methyl or ethyl groups. . In the low temperature state in such a process, there is a problem that CHX enters into the thin film. At high temperatures above 200 ~ 300 ℃, CHX decreases, making dense high quality thin film. If the temperature is higher than 400 ℃ hydrogen is difficult to control the escape, by adjusting the hydrogen inflow can be controlled the doping of the transparent semiconductor layer 20 and the resistance of the thin film.

In order to make a high quality thin film at low temperature, as shown in FIG. 5, the lower electrode may be controlled to sufficiently decompose CHX and be discharged into a gas such as CH 4 or H 2 O or CO or CO 2. For example, the RF power is also connected to the lower electrode in FIG. 5 by replacing with DC or MF power depending on the purpose. At this time, since sheath is formed on the substrate, radicals coming to the substrate bring some kinetic energy and this energy affects the formation of high quality thin film.

Here, sheath refers to a thin layer that does not emit light around the plasma, and radicals are a group of atoms that do not decompose when chemical change occurs and move to another molecule.

In addition, referring to FIG. 3, the method of stacking a functional thin film according to an exemplary embodiment of the present invention includes adjusting the resistance through n-type doping in the formed transparent semiconductor layer 20 (S220).

In addition, the transparent semiconductor layer 20 may be n-type doping with one of aluminum, gallium, and boron, the transparent semiconductor layer 20 may adjust the doping concentration by controlling the inflow of hydrogen, which is a reactive body of n-type doping, Resistance and visible light transmittance may be controlled by adjusting the doping concentration.

The transparent semiconductor layer 20 may be n-type doped through the above-described horizontally opposed target sputtering method or an auxiliary electrode applied PECVD method, and the doping concentration may be adjusted by adjusting the inflow of hydrogen, which is a reactive gas. Visible light transmittance can be adjusted.

Also, referring to FIG. 3, the method of stacking a functional thin film according to an exemplary embodiment of the present invention includes forming an insulating protective film 30 of SiOX on the transparent semiconductor layer 20 (S230). The insulating protective film 30 may be deposited by the above-described auxiliary electrode applied PECVD method. As the precursor, organosilanes such as tetraethylorthosilicate (TEOS), tetramethylenesulfoxide (TMSO), hexamethyldisiloxane (HMDSO), and octamethylcyclotetrasiloxane (OMCTS) may be used. In this structure, low temperature deposition below 100 ° C is possible.

In addition, an anti-fingerprint layer may be formed on the insulating protective layer 30 to prevent fingerprints from being applied.

The practical embodiment for satisfying the effective sheet resistance of 10MΩ / □ ~ 100M 으로 / □ of the functional thin film that can be used as a touch screen for the display by adjusting the resistance and the visible light transmittance through the aforementioned doping concentration adjustment.

During the process, the argon (Ar) gas used as a plasma gas is introduced while the process pressure is adjusted to 3 mT to 10 mT through the horizontally opposed target sputtering method or the auxiliary electrode applied PECVD method. When argon gas is introduced as 100, oxygen is added in 0-5 sccm and hydrogen is added in 1-4. In addition, the power is 1 ~ 10W / cm2. The temperature of the substrate is based on room temperature. The argon gas is an inert gas for plasma generation to maintain the process pressure. Oxygen and hydrogen are introduced into the reactor, which is approximately 1-5% of argon gas.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: functional thin film 10: transparent substrate
20: transparent semiconductor layer 30: insulating protective film
40: anti-fingerprint film S210: transparent semiconductor layer forming step
S220: resistance adjusting step S230: insulating protective film forming step

Claims (10)

In the functional thin film,
A transparent substrate;
A transparent semiconductor layer formed on the transparent substrate and including an oxide that maintains a transparent state in a visible light region; And
Insulating protective film formed on the transparent semiconductor layer,
The sheet resistance of the transparent semiconductor layer has a sheet resistance of 10MΩ / □ ~ 100MΩ / □,
When the n-type doping to the transparent semiconductor layer, the sheet resistance of the transparent semiconductor layer is controlled through the process of adjusting the flow rate of hydrogen, which is a reactive gas. The method of claim 1,
A functional thin film further comprising an anti-fingerprint film formed on the insulating protective film. The method of claim 1,
Said oxide is SnO2, n-type doped with fluorine; And
The oxide is ZnO, a functional thin film is n-type doping with one of aluminum, gallium, and boron. The method of claim 1,
The transparent semiconductor layer is a functional thin film thickness of 1nm ~ 100nm. The method of claim 1,
The insulating protective film is SiOx functional thin film. In the functional thin film lamination method,
Forming a transparent semiconductor layer on the transparent substrate through a sputtering method or a chemical vapor deposition method;
Controlling a resistance through n-type doping in the formed transparent semiconductor layer; And
Forming an insulating protective film of SiOx on the transparent semiconductor layer,
Adjusting the resistance is to adjust the resistance by adjusting the flow rate of hydrogen, which is a reactive gas,
The transparent semiconductor layer has a sheet resistance of 10MΩ / □ to 100MΩ / □, functional thin film stacking method. The method according to claim 6,
And the transparent semiconductor layer is n-type doped with aluminum, gallium, or boron. delete The method according to claim 6,
The transparent semiconductor layer is a functional thin film stacking method in which the resistance and the visible light transmittance is adjusted by adjusting the doping concentration. The method according to claim 6,
The method of claim 1, further comprising an anti-fingerprint coating step for preventing fingerprints from being deposited on the insulating protective film.

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