JP4835099B2 - Method for manufacturing plasma display panel - Google Patents

Description

  The present invention relates to a plasma display panel (hereinafter also referred to as a PDP) that has been increasingly used for public display of large televisions, advertisements, information, and the like, and a method for manufacturing the same.

  In recent years, flat panel display devices using display panels such as EL devices, SED devices, liquid crystal display (LCD) devices and PDP devices can be reduced in thickness and weight and have low power consumption. The demand for society as an industrial monitor has increased and is attracting attention. In particular, in a PDP that is excellent in visibility by exciting and emitting phosphors with ultraviolet light generated by rare gas discharge and used for image / video display, the size of the display area has recently increased from 50 inches to 80 inches. Products using screen PDPs have appeared. In the future, PDP devices with a larger display area exceeding 100 inches are also planned, and new technologies have been developed one after another aiming at higher performance, lower cost, and optimal mass production. Yes.

  There are an AC drive method and a DC drive method in the PDP. Here, a general AC drive method PDP (hereinafter, an AC drive method PDP is also referred to as an AC type PDP) will be described. Further, there are various types of AC type PDP, and FIG. 4 is a perspective view schematically showing the configuration of a type called a surface discharge type as an example. In the PDP, row electrodes and column electrodes are orthogonally arranged on a front plate PA1 and a back plate PA2 made of a transparent substrate such as glass, respectively, and a row 19 and a partition wall 19 between both substrates, which form pixels (pixels). Thus, the discharge space 30 is formed. Hereinafter, the configuration of the general surface discharge AC type PDP shown in FIG. 4 will be briefly described.

  The front plate PA1 has a plurality of scanning electrodes 12a for sequentially inputting a scanning signal for display and a sustain electrode 12b for inputting a sustaining signal for discharge on the front glass substrate 11 in parallel with each other in pairs. Display electrodes 12 serving as row electrodes are formed. A transparent dielectric layer 13 for forming wall charges due to discharge is formed on these display electrodes 12, and dielectric protection for protecting the dielectric layer 13 from ion bombardment due to discharge on the dielectric layer 13. A film (hereinafter also simply referred to as a protective film) 14 is formed. In addition, a light shielding layer 15 serving as a black matrix may be formed between the pair of the adjacent scanning electrode 12a and the sustaining electrode 12b as necessary in order to increase the contrast of the display surface.

  Next, the back plate PA2 has a direction in which address electrodes (also referred to as data electrodes) 17 serving as column electrodes for inputting a plurality of display data signals on the back glass substrate 16 intersect with the display electrodes 12 of the front plate PA1. A plurality are formed. A base dielectric layer 18 for forming wall charges due to discharge is also formed on the address electrode 17, and a partition wall 19 is formed on the base electrode parallel to the address electrode 17. Is provided with a phosphor layer 20 that emits red, green and blue light, respectively.

  Then, the front plate PA1 and the back plate PA2 are bonded to each other with their electrode forming surfaces facing each other, a sealing panel is formed using a sealing material such as frit glass, and degassing is performed while heating, and then the discharge gas A rare gas such as He, Ne, or Xe is sealed at a pressure of 400 Torr to 600 Torr, aging is performed by applying a drive pulse having a predetermined voltage and waveform to each electrode of the panel, and the discharge space 30 is The formed PDP panel 21 is completed.

  In the completed PDP panel 21, an electric signal is supplied to the display electrode 12 and the address electrode 17 including the scan electrode 12a and the sustain electrode 12b. Therefore, a circuit board on which a driver IC for driving is mounted on the terminals of these electrodes is provided. Connected and assembled into a casing together with a control signal circuit and a power supply circuit to complete a display device. By applying a voltage pulse of a predetermined signal to each electrode, the enclosed rare gas is discharged, and each color phosphor layer 20 provided between the barrier ribs 19 is excited by ultraviolet rays emitted by the discharge, thereby red, green, Blue visible light can be emitted to display information including color images.

  In particular, when the front plate PA1 is formed, the dielectric layer 13 is protected from ion bombardment due to discharge on the front glass substrate 11 on which the display electrode 12 including the scanning electrode 12a and the sustain electrode 12b and the dielectric layer 13 are formed. At the same time, the protective film 14 is formed by electron beam vapor deposition under predetermined conditions for the purpose of promoting the light emission of the phosphor by secondary electron emission. Generally, this protective film 14 is widely made of single crystal MgO. It has been. The MgO protective film 14 formed by a vacuum film formation technique such as electron beam evaporation is a highly crystalline and dense film and has excellent resistance to spattering. It has an excellent feature that it not only protects the body layer but also emits secondary electrons from the protective film 14 itself by ion bombardment and plays a role of lowering the driving voltage. The crystallographic structure and various physical properties of the protective film 14 are used to protect the dielectric layer 13 from ion bombardment caused by gas discharge, and to realize a discharge with a fast response by lowering the discharge voltage by a high secondary electron emission coefficient. Various proposals for improving the physical characteristics have been made (see, for example, Patent Document 1).

  Here, the principle of a general method for forming a MgO protective film will be briefly described with reference to a schematic diagram of a conventional vacuum vapor deposition apparatus for forming a protective film of MgO shown in FIG. Generally, the protective film 14 of PDP MgO is formed by a physical vapor phase method. The physical vapor phase method is a method of forming a thin film of a raw material on a target object by heating and evaporating or sublimating the solid raw material under a low pressure. Examples of the physical vapor phase method include a vacuum deposition method, a sputtering method, and an ion plating method.

  In FIG. 5, a vacuum deposition apparatus 40 is provided with a device comprising a hearth 44 serving as an MgO evaporation unit and a tray 47 serving as a substrate holding unit in a sealed container 42 to which a vacuum pump 41 is connected. The protective film forming raw material 43 made of MgO is supplied into the evaporation source pod 43a of the water-cooled hearth 44, and irradiated with a thermionic beam 46 emitted from the electron gun 45 in an oxygen atmosphere, to the evaporation source. A certain amount of heat is input to a certain raw material 43 and is heated and evaporated. At this time, the front plate PA1 is placed on a tray 47 having an opening 47a for supporting the substrate, moves from the left side to the right side in the direction of the arrow shown in FIG. 5, and the evaporated MgO passes through the opening 47a. Then, the MgO protective film 14 having a desired shape and film thickness is continuously formed on the front plate PA1 heated to a predetermined temperature by the substrate heater 48.

As described above, MgO, which is generally used as a protective film, has high sputter resistance in the discharge space, which is its original purpose, and at the same time, constant electron emission as an electrical behavior in the discharge space. It is required to be a film having characteristics. Therefore, the refractive index of the dielectric protective film is set to 1.4 to 2.0 with respect to light having a wavelength of 400 nm to 1000 nm so as to shorten the discharge delay time and enable high-definition high-quality display. Therefore, a method for improving the electron emission performance from the protective film has been proposed (see, for example, Patent Document 2). On the other hand, cost reduction is considered as a major issue in PDP manufacturing. Considering the productivity of a protective film formed mainly by expensive vacuum film formation, the panel characteristics of a transport-type film formation apparatus are In order to ensure this, it is necessary to improve the return on investment effect of production equipment by increasing the transfer speed while placing importance on the discharge characteristics. For this reason, production is performed by increasing the power required for film formation (the amount of heat input to the evaporation source). Therefore, it is necessary to ensure panel characteristics without sacrificing performance, and various film forming apparatuses and film forming methods for this purpose have been proposed (for example, see Patent Document 3).
Japanese Patent Laid-Open No. 11-54045 JP 2003-317631 A JP 2004-55180 A

  However, in the formation of a general MgO protective film by the physical vapor phase method described above, the refractive index of the protective film formed by increasing the input power at the time of film formation tends to decrease. Phenomena such as not only shortening the panel life but also changing discharge characteristics (for example, discharge voltage) over time are serious problems. The former problem of lowering the refractive index of the protective film can be dealt with to some extent by increasing the film thickness, but there is no method that can avoid the change in discharge characteristics over time. As described above, in addition to the vacuum deposition apparatus shown in FIG. 5, in the conventional method for forming a protective film of MgO as shown in the above-mentioned patent document, a method for achieving both mass productivity improvement and lifetime characteristic improvement is found. That was a big issue.

  The present invention has been made in order to solve the above-described problems, and for a certain thickness of the outermost surface of the protective film of MgO, by reducing the amount of heat input to the evaporation source and improving the sputter resistance, The object is to achieve both maintenance of performance including the time-dependent change of PDP and high mass productivity.

  In order to achieve the above object, the PDP according to the present invention includes a plurality of display electrodes each including a scan electrode and a sustain electrode and a dielectric layer sequentially formed, and the dielectric layer is covered with a protective film. A phosphor layer between barrier ribs which have address electrodes which are arranged opposite to each other so as to form a discharge space between the first substrate and the first substrate and which are formed in a direction perpendicular to the display electrodes and which partition the discharge space The plasma display panel (PDP) provided with the second substrate formed with a structure in which the refractive index on the lower layer side near the dielectric layer of the protective film is made smaller than the refractive index on the upper layer side.

Further, the PDP of the present invention has a structure in which the refractive index of the protective film continuously changes from the lower layer to the upper layer, and the protective film includes a plurality of layers having different refractive indexes, and the protective film In which the refractive index of the protective film changes intermittently from the lower layer to the upper layer, and when the refractive index of the protective film is n, the refractive index n is in the range of 1.4 ≦ n ≦ 2.0, and The maximum value of the ratio is 1.60 or more, and the protective film is MgO, Al ₂ O ₃ , CaO, BaO, TiO ₂ , Y ₂ O ₃ , La ₂ O ₃ , CeO ₂ , HfO ₂ A structure composed of any metal oxide or a mixed oxide containing any of the metal oxides, and a protective film formed by a physical vapor phase method, a chemical vapor phase method, a sol-gel method, a printing method, a coating method, or an impregnation method. A structure that is a protective film formed by any of the methods, Raniwa, protective film may be configured as a protective film formed by a physical vapor phase method using a vacuum deposition apparatus.

  With these structures, the protective film of MgO formed on the front plate of the PDP is formed with a distribution so that the refractive index changes from the lower layer to the upper layer, and the change with time in the discharge voltage in the display discharge It is possible to provide a PDP with excellent display quality over a long period of time.

In order to achieve the above object, a method for manufacturing a PDP according to the present invention includes a plurality of display electrodes and a dielectric layer that are sequentially formed of scan electrodes and sustain electrodes, and the dielectric layer is a protective film. A partition wall having an address electrode which is disposed so as to form a discharge space between the coated first substrate and the first substrate and which is formed in a direction orthogonal to the display electrode and which partitions the discharge space A plasma display panel (PDP) manufacturing method comprising a second substrate having a phosphor layer formed therebetween, and enclosing a discharge gas in a discharge space, wherein a protective film is formed by a physical vapor deposition method using a vacuum deposition apparatus is formed by a vacuum deposition apparatus comprises at least two places or more evaporation sources, performs a film formation by sequential thermal evaporation, and comprising the step of step of introducing heat different respective evaporation sources, the protective film The lower layer index of refraction near the collector layer be smaller than the refractive index of the upper layer side.

  By this PDP manufacturing method, a protective film of MgO covering the dielectric layer constituting the front plate of the PDP can be formed with a distribution such that the refractive index changes from the lower layer to the upper layer, As a result, it is possible to provide an excellent PDP display device in which the change over time of the discharge voltage is small and the change in display quality is small over a long period of time. In addition, it is possible to realize a method for manufacturing a PDP that enables both improvement in mass productivity and improvement over time.

  According to the present invention, the protective film of MgO covering the dielectric layer of the AC surface discharge type PDP is formed with a distribution so that the refractive index changes from the lower layer to the upper layer, and as a result, The change over time in the discharge voltage can be reduced, and a PDP with excellent display quality can be realized. With such a PDP panel having a protective film, it is possible to provide an excellent PDP display device in which the discharge characteristics in the display screen change little over time and the display quality changes little over a long period of time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  In the embodiment of the present invention, the PDP has a structure similar to that of the surface discharge AC type PDP whose example is shown in FIG. 4 in the description of the background art, and for forming the protective film shown in the schematic diagram of FIG. It is assumed that it is manufactured by the same manufacturing method as described in the outline of the manufacturing procedure.

(Embodiment)
The PDP in the embodiment of the present invention will be briefly described once again with reference to FIG. The surface discharge AC type PDP shown in FIG. 4 generates a discharge in the discharge space 30 by applying a pulse voltage to each electrode, and the red and green generated on the back plate PA2 side along with the discharge. , Blue visible light is transmitted from the main surface of the front plate PA1.

  The front plate PA1, which is the first substrate, is a front surface on which the display electrodes 12 are formed by arranging a plurality of pairs of scanning electrodes 12a and sustaining electrodes 12b in stripes (for convenience, one pair is extended in FIG. 4). A dielectric layer 13 is formed on the glass substrate 11 so as to cover the display electrodes 12. Further, a protective film 14 is formed so as to cover the dielectric layer 13.

  A plurality of address electrodes 17 are arranged on the rear glass substrate 16 in a stripe shape so as to be orthogonal to the display electrodes 12 including the scan electrodes 12a and the sustain electrodes 12b on the rear plate PA2 that is the second substrate. . The underlying dielectric layer 18 is formed so as to cover the address electrodes 17 and protects the address electrodes 17 and has a function of reflecting visible light to the front panel side. On the underlying dielectric layer 18, partition walls 19 are provided so as to extend in the same direction as the address electrodes 17 so as to sandwich the address electrodes 17, and a phosphor layer 20 is disposed between the partition walls 19.

  The pair of scan electrodes 12a and sustain electrodes 12b constitute the display electrode 12, and a discharge space 30 is formed by being surrounded by the barrier ribs 19 at a portion where these and the address electrode 17 intersect. A discharge is generated in the discharge space 30 constituting each pixel, and the visible light of three colors of red, green, and blue generated from the phosphor layer 20 accompanying the discharge is transmitted through the front plate PA1, thereby displaying the display. Done.

  The PDP according to the present invention is characterized by the characteristic of the protective film 14 that the refractive index is not uniform in the film thickness direction and the formation method thereof, and the contents thereof will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is a schematic view of a vacuum deposition apparatus for forming a protective film of a PDP in an embodiment of the present invention, and FIG. 2A is an MgO protective film formed on the PDP in the embodiment of the present invention and having different refractive index distributions. FIG. 2B is a graph showing the structure of the film, FIG. 2B is a graph showing the change in discharge voltage during continuous lighting with respect to the MgO protective film having a different refractive index distribution, and FIG. 3 is formed in the PDP according to the embodiment of the present invention. 6 is a graph showing the change in discharge voltage after 10,000 hours of continuous lighting with respect to the refractive index of the MgO protective film having various upper layer refractive indexes. In addition, in each figure, the same code | symbol is attached | subjected to the same component as FIG. 4, FIG. 5, and detailed description of the overlapping component is abbreviate | omitted.

  Hereinafter, the principle of the PDP MgO protective film forming method in the embodiment of the present invention will be described using the vacuum vapor deposition apparatus 50 for forming the PDP MgO protective film in the embodiment of the present invention shown in FIG. The configuration of the vacuum vapor deposition apparatus 50 shown in FIG. 1 is different from the general vacuum vapor deposition apparatus 40 for forming the MgO protective film shown in FIG. A second vapor deposition source disposed in the evaporation source pod 53a and a second electron gun 55 for heating the second vapor deposition source are provided.

  In FIG. 1, a vacuum deposition apparatus 50 is provided with a device composed of a hearth 44 serving as an MgO evaporation unit and a tray 47 serving as a substrate holding unit in a sealed container 42 to which a vacuum pump 41 is connected. The protective film forming raw materials 43 and 53 made of metal oxide pellets such as MgO are supplied to the evaporation source pod 43a and the second evaporation source pod 53a of the water-cooled hearth 44, respectively, and an electron gun in an oxygen atmosphere. The thermal electron beams 46 and 56 emitted from the 45 and the second electron gun 55 are irradiated to be heated and evaporated. The evaporated MgO adheres to the front plate PA1, which is a substrate heated to a predetermined temperature by the substrate heater 48. Here, the front plate PA1 is placed on a tray 47 having an opening 47a for supporting the substrate, and the evaporated MgO passes through the opening 47a, so that a desired protective film 14 of MgO is formed.

  In forming the protective film 14, it is necessary to supply oxygen gas during film formation. By supplying oxygen gas into the hermetic container 42 serving as a vacuum film formation chamber (vacuum chamber) of the vacuum vapor deposition apparatus 50, the protective film 14 is controlled to have a target film thickness. When a metal oxide such as MgO, which is a film raw material, is evaporated by electron beam irradiation, oxygen atoms are easily desorbed from the film raw material. Therefore, a film formed without supplying oxygen gas is likely to be in an oxygen deficient state. Therefore, it is necessary to always supply oxygen gas to the growth surface. Thus, by performing film formation while supplying oxygen gas, the transparency to visible light can be increased as a result.

The film quality / characteristics and film thickness of the protective film 14 are arbitrarily controlled by various film forming parameters such as the heating temperature, oxygen gas pressure, electron beam intensity from the electron gun, and deposition rate of the front plate PA1 as a substrate. be able to. In order to use as the protective film 14 in the PDP, it is preferable to set the substrate temperature to 200 ° C. or higher and the oxygen gas pressure to the 10 ⁻² Pa level. By controlling the film formation parameters to change in a direction perpendicular to the surface of the front plate PA1 to be formed, the film quality and characteristics of the protective film 14 can be distributed in the film thickness direction. become.

  Hereinafter, as an example, a description will be given of an example in which the refractive index among the film quality and characteristics of the protective film 14 of the PDP in the embodiment of the present invention is formed with a distribution in the film thickness direction. First, an example of deposition film forming conditions when a protective film of MgO whose refractive index changes in the film thickness direction is formed by the vacuum vapor deposition method using the vacuum vapor deposition apparatus 50 shown in FIG. 1 will be described.

Ultimate pressure: 5.0 × 10 ⁻⁴ Pa or less Temperature of substrate during vapor deposition (front plate PA1): 250 ° C.
・ Emission current of electron gun 45: 250 mA
-Emission current of the second electron gun 55: 200 mA
・ Pressure during deposition: 2.0 × 10 ⁻² Pa
The distance between the evaporation source pod 43a and the second evaporation source pod 53a: 20 cm
In this example, in order to change the refractive index in the film thickness direction, the intensity of each electron beam of the two electron guns, that is, the emission current of the electron gun is changed. Forming the MgO protective film 14 whose refractive index continuously decreases from the upper layer portion of the MgO protective film 14 toward the lower layer near the dielectric layer 13 by performing vacuum deposition under the above conditions. I was able to.

  In the example of forming the MgO protective film of PDP in the above-described embodiment of the present invention, the evaporation was performed while the distance between the evaporation sources, that is, the evaporation source pods, was relatively short. By taking it (for example, 1 m or more), it is possible to create an MgO film in which the refractive index of the protective film changes intermittently in layers from the lower layer to the upper layer. In the vacuum vapor deposition apparatus shown in FIG. 1, the film is formed by providing two MgO evaporation sources. However, it is also possible to perform the film formation by providing three or more places. It is also possible to control the refractive index. Furthermore, it is possible to form a protective film using not only the above-described vacuum deposition method but also sputtering method, ion plating method, etc. In this case as well, a plurality of evaporation sources are prepared to control film formation. It can also be done.

  Next, characteristics of the PDP having a protective film formed using the vacuum deposition apparatus shown in FIG. 1 in the embodiment of the present invention will be described. As shown in FIG. 2A, the protective film of MgO has a refractive index of 1.53 in the film thickness direction and a uniform film (A) and a refractive index of 1.53 to 1.65 from the lower layer to the upper layer. Three types of protective films were formed: a film (B) that was continuously changed to (1), and a film (C) in which the refractive index of the lower layer was 1.53 and the refractive index of the upper layer was changed discontinuously to 1.65. A continuous lighting test was performed using a PDP prototyped using a coated front plate. FIG. 2B shows the relationship between the lighting time and the change with time of the discharge voltage in each MgO film. From this result, compared with the film (A) used in the conventional PDP having a uniform refractive index in the film thickness direction, the upper layer of the film (B) and the film (C) with a protective film of MgO are used. It was confirmed that the change over time in the discharge voltage during continuous lighting was small.

  In addition, five types of protective films in which the refractive index of the lower layer of the MgO protective film is 1.53 and the refractive index of the upper layer is changed to 1.53, 1.55, 1.58, 1.60, 1.65 are provided. FIG. 3 shows the result of measuring the amount of change in the discharge voltage after lighting for 10,000 hours using each PDP prototyped using the front plate having the same. From this result, it has been clarified that the discharge voltage change becomes 3 V or less and becomes very small by forming the upper layer with a refractive index of 1.60 or more. The results shown here show that, by setting the refractive index of the protective film of MgO to 1.60 or more, a dense protective film with good crystallinity is obtained, the ion impact resistance of the protective film is improved, and the lifetime of the PDP This is considered to indicate that the length can be increased. The refractive index of the protective film described above is a value measured with an ellipsometer.

  In the background art, it has already been described that the refractive index of the protective film of MgO is desirably set to 1.4 to 2.0 in order to increase the electron emission performance. Even in the case of a PDP panel, a film having a refractive index exceeding 2.0 cannot increase the initial discharge voltage to obtain good PDP panel characteristics, and is also formed by greatly increasing the input power during deposition. Even a film having a rate of 1.4 or less has poor crystallinity, and in this case, it has been confirmed that good PDP panel characteristics cannot be obtained, and caution is required.

  In the above description, regarding the MgO protective film composed of a plurality of layers having different refractive indexes, the refractive index on the lower layer side is 1.53 and the refractive index on the upper layer side is 1.65 as shown in FIG. However, the PDP in the embodiment of the present invention is not limited to this protective film, and consists of a plurality of three or more layers, and the refractive index of the lower layer film is Another configuration in which the refractive index of the upper layer side film is 1.4 or more and 2.0 or less may be used.

  From the results described above, the protective film of MgO formed based on the method described in the embodiment of the present invention is formed with a distribution so that the refractive index changes from the lower layer to the upper layer. It was confirmed that the change in the discharge voltage was small in the lighting test over 10,000 hours. That is, in the MgO protective film formed based on the method described in the embodiment, the change with time of the discharge voltage in the display discharge can be reduced, and a PDP with excellent display quality can be realized.

  Further, in the above-described embodiments, the formation of the protective film has been described by taking the physical vapor phase method as an example, but the present invention is not limited to this, and the chemical vapor phase method, the sol-gel method, the printing method, The protective film can also be formed by other methods such as a coating method and an impregnation method.

In the PDP in the embodiment of the present invention, MgO is used as the material for the protective film, but the present invention is not limited to this, and besides MgO, Al ₂ O ₃ , CaO, BaO, TiO ₂ , Y ₂ O ₃ , La ₂ O ₃ , CeO ₂ , HfO _{2 and} other metal oxides and mixed oxides containing these metal oxides, which have excellent ion impact resistance and secondary electron emission coefficient Any material may be used as long as the material is large.

  In the present invention, a protective film of MgO covering the dielectric layer is formed with a distribution so that the refractive index changes from the lower layer to the upper layer, and as a result, the change with time in the discharge voltage is reduced. Therefore, it is possible to provide an excellent PDP display device with little change in display quality over a long period of time, and it is particularly effective when applied as a PDP manufacturing method capable of improving both mass productivity and improvement with time. .

The schematic diagram of the vacuum evaporation system for protective film formation of PDP in embodiment of this invention (A) is a figure which shows the structure of the MgO protective film which is formed in PDP in embodiment of this invention, and has different refractive index distribution, (b) is the MgO protective film which has different refractive index distribution at the time of continuous lighting Graph showing change in discharge voltage The graph which shows the amount of discharge voltage changes after 10,000 hours continuous lighting with respect to the refractive index of the MgO protective film which is formed in PDP in embodiment of this invention and has the refractive index of various upper layers A perspective view showing a schematic configuration of a general surface discharge AC type PDP Schematic diagram of a conventional vacuum evaporation system for MgO protective film formation

Explanation of symbols

PA1 Front plate (first substrate)
PA2 Back plate (second substrate)
DESCRIPTION OF SYMBOLS 11 Front glass substrate 12 Display electrode 12a Scan electrode 12b Sustain electrode 13 Dielectric layer 14 (Dielectric material) Protective film 15 Light shielding layer 16 Back glass substrate 17 Address electrode 18 Base dielectric layer 19 Partition 20 Phosphor layer 21 PDP panel 30 Discharge Space 40, 50 Vacuum evaporation apparatus 41 Vacuum pump 42 Sealed container 43, 53 (For protective film formation) Raw material 43a Evaporation source pod 44 Hearth 45 Electron gun 46, 56 Thermoelectron beam 47 Tray 48 Substrate heater 53a Second evaporation source pod 55 Second electron gun

Claims (1)

A plurality of display electrodes and dielectric layers composed of scan electrodes and sustain electrodes are sequentially formed, and a discharge is generated between the first substrate having the dielectric layer covered with a protective film and the first substrate. A second substrate having an address electrode formed so as to be opposed to each other so as to form a space and formed in a direction perpendicular to the display electrode and having a phosphor layer formed between partition walls defining the discharge space; A method of manufacturing a plasma display panel in which a discharge gas is sealed in the discharge space, wherein the protective film is formed by a physical vapor phase method using a vacuum deposition apparatus,
The vacuum evaporation apparatus includes at least two evaporation sources;
A film is formed by sequential heating vapor deposition, and different amounts of heat are put into the evaporation source,
A method of manufacturing a plasma display panel, wherein a refractive index on a lower layer side of the protective film near the dielectric layer is made smaller than a refractive index on an upper layer side.

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