Patent Application
20070281178
The above and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings of which:
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
A silver (Ag) target is used, and argon is used as a sputtering gas in the first Ag layer 330-1. In this instance, an amount of the argon used corresponds to approximately 160˜200 sccm. Also, when forming the Nb2O5 layers 310-1 and 310-2, the argon is used as the sputtering gas and an oxygen is used as a reactive gas. In this instance, an amount of the argon used may be approximately 140˜210 sccm, and an amount of the oxygen may be approximately 4˜12%, preferably about 8˜12%, of the amount of the argon used. Also, when forming the AZO layer 320-1, the argon is used as the sputtering gas and the oxygen is used as the reactive gas. In this instance, an amount of the argon used may be approximately 160˜200 sccm, and an amount of the oxygen may be approximately 8˜12% of the amount of the argon used. A direct current (DC) sputtering or a mid-frequency (MF) sputtering is available for the Ag layer 330-1, the AZO layer 320-1, and the Nb2O5 layers 310-1 and 310-2.
In the multi-layer thin film according to the present invention, a metal thin film layer is formed by silver or an alloy containing the silver. The silver may be effectively used, since the silver has an excellent conductivity, infrared ray reflectance, and light transmittance when multilayered. However, the silver lacks a chemical and physical stability, and is degraded by an environment such as pollutants, vapors, heat, and light. Accordingly, the alloy of the silver and at least one of gold, platinum, palladium, indium, and tin, which are stable, may be favorably utilized. In this instance, a silver content of the alloy may correspond to a value of less than approximately 50-100 wt %, although the silver content of the alloy is not particularly limited. Generally, when adding another metal to the silver, the excellent conductivity and optical characteristics of the silver may be reduced. Accordingly, at least one metal thin film layer of a plurality of metal thin film layers is required not to contain the alloy of the silver and another metal. When an entire metal thin film layer is made up of the silver which is not the alloy, a multi-layer thin film may have excellent conductivity and optical characteristics. However, resilience against the environment may be poor.
Referring to
In this instance, the transparent substrate 210 is generally manufactured by using a tempered glass or a semi-tempered glass having a thickness of approximately 2.0˜3.5 mm, or a transparent plastic material such as an acrylic. The transparent substrate 210 may preferably have a high transparency and thermal resistance. Also, a high polymer compound and a stacking body of the high polymer compound may be used as the transparent substrate 210. The transparent substrate 210 may preferably have a light transmittance of at least 80% and a glass transition temperature of at least approximately 60° C. The high polymer compound may be transparent in a visible wavelength spectrum. Also, polyethylene terephthalate (PET), polysulfone (PS), polyethersulfone (PES), polystyrene, polyethylene naphthalate, polyarylate, polyether ether ketone (PEEK), polycarbonate (PC), polypropylene (PP), polyimide, a triacetyl cellulose (TAC), and polymethyle methacrylate (PMMA) may be included in the high polymer compound. However, the high polymer compound described above may not be limited to the above-named compounds. The PET is advantageous in terms of a price, a thermal resistance, and a transparency.
In
The first Nb2O5 layer 310-1, the first AZO layer 320-1, and the first Ag layer 330-1, which are formed through operations described above, form one repeating unit layer. After forming the repeating unit layer, the PDP filter having the multi-layer thin film may be manufactured by stacking a second high refractive transparent thin film layer on a top of the first Ag layer 330-1. According to the conventional art, a second oxide layer 250, i.e. a second ITO layer, is applied prior to the forming of the second high refractive transparent thin film layer, as shown in
According to an embodiment of the present invention, at least two repeating unit layers described above may be stacked.
When at least three repeating unit layers are included, a high refractive transparent thin film layer of the repeating unit layer which is the closest to the transparent substrate 210, and a high refractive transparent thin film layer of the repeating unit layer which is the farthest to the transparent substrate 210 have an identical thickness. A thickness of a high refractive transparent thin film layer of the repeating unit layer which is located in the middle of the at least three repeating unit layers is different from the thickness of the high refractive transparent thin film layers having identical thickness. Depending on a number of the repeating unit layer, physical characteristics of the PDP filter may vary, which will be described in detail below.
A second repeating unit layer is sequentially stacked on the first Ag layer 330-1 which is described with reference to
A third repeating unit layer is sequentially stacked on the second repeating unit layer. In this instance, a thickness of the third Nb2O5 layer 310-3 may be approximately 25˜33 nm, preferably about 27˜33 nm, and a thickness of the third AZO layer 320-3 may be approximately 3˜7 nm. Also, a thickness of the third Ag layer 330-3 may be approximately 10˜12 nm. Each thickness of the Nb2O5 layer and the AZO layer of the third repeating unit layer is identical to each respective thickness of the Nb2O5 layer and the AZO layer of the first repeating unit layer.
A PDP filter having the multi-layer thin film including three repeating unit layers may be manufactured by stacking a fourth Nb2O5 layer 310-4 on a top of the third repeating unit layer. In this instance, a thickness of the fourth Nb2O5 layer 310-4 may be 25˜33 nm.
According to an embodiment of the present invention, when applying an Nb2O5 layer, the Nb2O5 layer is applied using an Nb2O5 target, i.e. a ceramic target, instead of using a niobium (Nb) target and a reactive sputtering method, in an argon atmosphere. When using the reactive sputtering, an amount of oxygen and argon (Ar) injected corresponds to approximately 200 sccm: When using the ceramic target, an amount of the argon injected corresponds to approximately 140˜210 sccm. Also, an amount of oxygen injected corresponds to approximately 4˜12%, preferably about 8˜12%, of the amount of the argon. Accordingly, after coating the Ag layer, an electrical conductivity of the Ag layer is not degraded, even when the Nb2O5 layer is applied on the Ag layer. Thus, properties of the repeating unit layer does not change even when omitting a barrier layer. Specifically, according to the conventional art, the barrier layer such as an ITO layer or an AZO layer is applied in order to prevent the electrical conductivity of the Ag layer from being degraded due to an oxygen plasma while applying the Nb2O5 layer. However, in the present invention, the barrier layer may be omitted. Specifically, four second oxide film layers of the 4-Ag structure shown in
An average refractive index of a high refractive transparent thin film layer of the multi-layer thin film according to the present invention is greater than an average refractive index of a high refractive transparent thin film layer according to the conventional art. In this instance, the high refractive transparent thin film layer according to the conventional art has the barrier layer. Accordingly, light transmittance and a light transmittance bandwidth of the high refractive transparent thin film layer according to the present invention are improved.
The PDP filter including three repeating unit layers as shown in
Similar to the description of the multi-layer thin film of
A thickness of a first Nb2O5 layer 410-1 included in the first repeating unit layer may be approximately 25˜33 nm, preferably about 27˜33 nm, and a thickness of a first AZO layer 420-1 may be approximately 3˜7 nm. Also, a thickness of a first Ag layer 430-1 may be approximately 10˜12 nm.
A second Nb2O5 layer 410-2, a second AZO layer 420-2, and a second Ag layer 430-2 are sequentially stacked. In this instance, a thickness of the second Nb2O5 layer 410-2 included in a second repeating unit layer may be approximately 25˜33 nm, preferably about 27˜33 nm, and a thickness of the second AZO layer 420-2 may be approximately 3˜7 nm. Also, a thickness of the second Ag layer 430-2 may be approximately 11˜14 nm.
A thickness of a third Nb2O5 layer 410-3 included in a third repeating unit layer may be approximately 25˜33 nm, preferably about 27˜33 nm, and a thickness of a third AZO layer 420-3 may be approximately 3˜7 nm. Also, a thickness of a third Ag layer 430-3 may be approximately 11˜14 nm. Specifically, each layer's thickness of the third repeating unit layer is identical to each respective layer's thickness of the second repeating unit layer.
A thickness of a fourth Nb2O5 layer 410-4 may be approximately 25˜33 nm, preferably about 27˜33 nm, and a thickness of a fourth AZO layer 420-4 may be approximately 3˜7 nm. Also, a thickness of a fourth Ag layer 430-4 may be approximately 10˜12 nm. Specifically, each layer's thickness of the fourth repeating unit layer is identical to each respective layer's thickness of the first repeating unit layer.
A PDP filter having the multi-layer thin film including the repeating unit layers may be completed by stacking a fifth Nb2O5 layer 410-5 on a top of the fourth repeating unit layer. In this instance, a thickness of the fifth Nb2O5 layer 410-5 may be 25˜33 nm.
The PDP filter including the repeating unit layers as shown in
In the present invention, a preferable number of the repeating unit layers is 3 to 6 repeating unit layers. Although the multi-layer thin films including three or four repeating unit layers in
In the present invention, in order to improve a mechanical strength or resilience against an environment of the multi-layer thin film, a hard coating layer may be formed on a surface excluding a surface in which the multi-layer thin film of the transparent substrate is stacked. Also, a predetermined protection layer which does not degrade conductivity and optical characteristics may be formed on a conductive surface. In this instance, the conductive surface refers to a surface where the repeating unit layer is formed on the transparent substrate.
Also, in order to improve resilience against an environment of the metal thin film and an adherence of the metal thin film with the high refractive transparent thin film, a predetermined inorganic material which does not damage the conductivity and the optical characteristic may be included between the metal thin film and the high refractive transparent thin film. The inorganic material may include copper, nickel, chrome, gold, platinum, zinc, zirconium, titan, tungsten, tin, palladium, or an alloy of at least two inorganic materials described above. A preferable thickness of the inorganic material corresponds to 0.02˜2 nm. The adherence may not be improved when the thickness is insufficient. Also, a multi-layer thin film having increased light transmittance may be obtained by forming a reflection prevention layer which is composed of a mono-layer or a multi-layer on a top portion of the multi-layer thin film.
According to the present invention, a conductive film filter which is located on a silver (Ag) thin film and does not suffer degradation in conductivity, and a conductive material of a PDP filter without requiring an additional oxide protection layer is provided.
According to the present invention, a target cost for a deposition of a conventional second oxide film may be reduced without a reduction in conductivity, and retard a degradation process of the conventional second oxide film.
According to the present invention, a PDP filter having a simple-structured multi-layer thin film is provided, and thereby may improve a refractive index and light transmittance of the PDP filter.
According to the present invention, a coating method without requiring a great amount of added oxygen is provided and thereby may increase productivity of a coating facility.
According to the present invention, a PDP filter having a multi-layer thin film which does not require an additional formation of a second oxide film layer according to a conventional art, is provided.
Although a few embodiments of the present invention have been shown and described, the present invention is not limited to the described embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2006-0048495 | May 2006 | KR | national |
