JP2005353455A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display panel with discharge voltage lowered in a discharge space. <P>SOLUTION: The plasma display panel is provided with a first substrate, a second substrate opposing the first substrate, a first electrode formed on a side of the first substrate opposing the second substrate, a second electrode formed on a side of the second substrate opposing the first substrate, a first dielectric layer formed so as to cover the first electrode, a second dielectric layer formed so as to cover the second electrode, a protective film made of an MgO film containing a polycrystalline structure formed so as to cover the first dielectric layer, and a discharge space formed between the protective film and the second dielectric layer. The protective film has a localized level of the MgO, with a content of the localized level larger than that of a single-crystal MgO. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a plasma display panel, and more particularly to a plasma display panel having a protective film made of MgO.

  Plasma display panel (Plasma Display Panel, hereinafter referred to as PDP) has features such as easy screen enlargement, good display quality, and wider viewing angle compared to liquid crystal display. Since it can be made thinner, it has come to be used as a large display device such as a wall-mounted display.

  An outline of the operating principle of the PDP is that a rare gas is excited by causing discharge in a discharge space in which a sealed gas made of a rare gas, for example, called a display cell is sealed, and phosphors are generated by ultraviolet rays generated by the optical transition thereof. And visible light from the phosphor is used for display light emission.

  The general structure of a conventional PDP has a structure in which electrodes are provided on two substrates disposed so as to face each other, and the discharge space is formed between these electrodes. The electrodes formed so as to face each other across the discharge space are called display electrodes and data electrodes, for example, and each of the display electrodes and the data electrodes has a structure covered with a dielectric layer. doing.

  For example, a phosphor layer is formed on a dielectric layer covering the data electrode, and is an element that determines the color of a pixel when the PDP emits light. On the other hand, a protective film is formed on the dielectric layer covering the display electrode, and the dielectric layer is protected from damage due to sputtering.

  In this case, the discharge characteristics of the discharge space are greatly influenced by the protective film facing the discharge space, particularly when the secondary electron emission gain of the protective film is high, that is, when secondary electrons are more likely to be emitted. In addition, it has been found that the discharge voltage in the discharge space is lowered, and therefore, MgO having a relatively high secondary electron gain is generally used for the protective film.

  In addition, a low discharge voltage is an important characteristic in PDPs that require high brightness and high definition in recent years. For example, in order to achieve high brightness and high definition, there is a method of increasing the partial pressure of Xe gas in the sealed gas sealed in the discharge space, but if the partial pressure of Xe gas is increased, the discharge voltage is increased. There was a problem of rising.

Therefore, various methods have been proposed for producing a protective film made of MgO for reducing the discharge voltage. (For example, see Patent Document 1 and Patent Document 2.)
JP-A-5-234519 JP 2000-277209 A

  However, as a method for forming a protective film made of an MgO film, various proposals have been made regarding various conditions such as temperature and partial pressure during manufacturing. However, the MgO film is preferable for reducing the discharge voltage in the discharge space of the PDP. This structure, details of the structure, and a method for verifying the structure of the MgO film are not clear. For this reason, the quality of the MgO film differs due to slight differences in conditions when forming the MgO film, and the PDP using the MgO film as a protective film does not provide sufficient discharge characteristics. May increase.

  Therefore, an object of the present invention is to provide a novel and useful plasma display panel that solves the above-described problems.

  A specific problem of the present invention is to provide a PDP using an MgO film having a structure for reducing a discharge voltage as a protective film of a dielectric layer covering an electrode.

  In the first aspect of the present invention, the above-described problems are solved on the first substrate, the second substrate facing the first substrate, and the side of the first substrate facing the second substrate. A first electrode formed; a second electrode formed on a side of the second substrate facing the first substrate; and a first dielectric formed so as to cover the first electrode. A body layer, a second dielectric layer formed so as to cover the second electrode, and a protective film made of an MgO film including a polycrystalline structure formed so as to cover the first dielectric layer; A plasma display panel having a discharge space formed between the protective film and the second dielectric layer, wherein the protective film has a localized level of MgO, and the localized level The plasma display panel is characterized in that the content of is higher than the content of the localized level of single crystal MgO. To.

  According to the plasma display panel, since the MgO film having a structure for reducing the discharge voltage is used for the protective film of the dielectric layer covering the electrodes, the discharge voltage of the plasma display panel can be reduced.

  In the second aspect of the present invention, the above-described problem is solved on the first substrate, the second substrate facing the first substrate, and the side of the first substrate facing the second substrate. A first electrode formed; a second electrode formed on a side of the second substrate facing the first substrate; and a first dielectric formed so as to cover the first electrode. A protective layer composed of a body layer, a second dielectric layer formed to cover the second electrode, an MgO film formed to cover the first dielectric layer, and the protective film; A discharge space formed between the second dielectric layers, wherein the protective film has a localized level of MgO, and the content of the localized level is This is solved by a plasma display panel characterized in that it is 14 to 20 times the content of localized levels of single crystal MgO. .

  According to the plasma display panel, since the MgO film having a structure for reducing the discharge voltage is used for the protective film of the dielectric layer covering the electrodes, the discharge voltage of the plasma display panel can be reduced.

  In the third aspect of the present invention, the above-described problems are solved on the first substrate, the second substrate facing the first substrate, and the side of the first substrate facing the second substrate. A first electrode formed; a second electrode formed on a side of the second substrate facing the first substrate; and a first dielectric formed so as to cover the first electrode. A protective layer composed of a body layer, a second dielectric layer formed to cover the second electrode, an MgO film formed to cover the first dielectric layer, and the protective film; A plasma display panel provided with a discharge space formed between the second dielectric layers, wherein the protective film has an area at a wavelength of 300 nm to 600 nm of spectral characteristics of cathodoluminescence measurement for the MgO single crystal film. A plastic having an intensity ratio of 14 to 20 times By Ma display panel, resolve.

  According to the plasma display panel, since the MgO film having a structure for reducing the discharge voltage is used for the protective film of the dielectric layer covering the electrodes, the discharge voltage of the plasma display panel can be reduced.

  According to the present invention, since the MgO film having a structure for reducing the discharge voltage is used for the protective film of the dielectric layer covering the electrodes, the discharge voltage of the PDP can be reduced.

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

  FIG. 1A schematically shows a cross-sectional view of one display cell having a structure of an AC drive type PDP according to Embodiment 1 of the present invention, and FIG. The figure is shown. FIG. 2 is a perspective view of an AC drive type color PDP 10 in which a plurality of the display cells shown in FIGS. 1A and 1B are arranged.

  Referring to FIGS. 1A, 1B and 2, in the PDP 10, the front plate 11 and the back plate 15 made of a glass substrate are arranged to face each other with the discharge space 20 in between. A display electrode 12 is disposed on the front plate 11 on the side facing the back plate 15. The display electrode 12 is covered with a dielectric layer 13 made of, for example, lead oxide glass, and the like. The dielectric layer 13 is covered with a protective film 14 made of MgO. The display electrode 12 is configured by arranging a pair of strip-like scan electrodes and sustain electrodes in parallel with each other.

  A plurality of strip-shaped data electrodes 16 orthogonal to the display electrodes 12 are provided on the back plate 15 on the side facing the front plate 11, and the plurality of data electrodes 16 are parallel to each other. The data electrodes 16 are arranged and covered with a dielectric layer 17.

  Further, a partition wall 18 separating the plurality of data electrodes 16 and forming the discharge space 20 is provided on the dielectric layer 17 substantially in parallel with the data electrodes 16. A phosphor layer 19 is formed from the dielectric layer 17 on the data electrode 16 to the side surface of the partition wall 18. The PDP 10 shown in FIG. 2 has a structure in which, for example, red, green, and blue phosphors 19 are sequentially arranged with the partition wall 18 interposed therebetween in order to enable color display.

  In the PDP 10, the dielectric layers 13 and 17 are provided for accumulating charges generated by applying a voltage to the display electrode 12 and the data electrode 16.

  FIG. 2 shows a shape in which three display cells are combined as an example, but the number of display cells is arbitrary, and actually a PDP that is a large display device by combining a larger number of display cells. Form.

  The operation principle of the PDP 10 is as follows. First, the reset discharge of the display electrode 12 (between the scan electrode and the sustain electrode) is performed in the discharge space 20 of all the cells, the wall charge state is made the same, and then the scan electrode of the display electrode 12 is scanned. At the same time, a voltage is selectively applied to the data electrode 16 to cause an address discharge in the discharge space 20.

  As a result, wall charges are selectively formed on the display electrode 12. Therefore, when a discharge sustain voltage is next applied to the display electrode 12, it is possible to control whether or not a discharge is generated in the discharge space 20, and depending on the number of sustain discharges in the discharge space 20, an image can be obtained. An image can be displayed by controlling display gradation.

  The discharge space 20 is filled with an enclosed gas made of an inert gas, and the enclosed gas is made of, for example, a mixed gas of at least one of He, Ne, Ar, and Kr and Xe. In addition, the luminous efficiency of the PDP greatly depends on the enclosed gas. For example, increasing the Xe mixing ratio of the enclosed gas or the ratio of the partial pressure of Xe to the total pressure of the enclosed gas improves the luminous efficiency. It is possible to increase the brightness and definition of the PDP.

  However, conventionally, when the partial pressure of Xe in the sealed gas is increased, the discharge voltage in the discharge space tends to increase and the driving voltage of the PDP tends to increase, and it is difficult to increase the partial pressure of Xe. It was. However, in this embodiment, since the structure of the protective film 14 made of MgO is formed so that the discharge voltage is lowered, the driving voltage of the PDP is lowered and the partial pressure of Xe in the sealed gas is further increased. In order to achieve the effect of suppressing the increase in the driving voltage in this case, the luminous efficiency can be improved by increasing the partial pressure of Xe.

  As described above, when the discharge voltage is lowered, not only the operation voltage of the PDP is suppressed and the power consumption is reduced, but also the effect that the brightness and the definition of the PDP can be increased is achieved.

  For example, a discharge voltage such as a discharge start voltage and a discharge sustain voltage in the discharge space 20 is emitted from the surface of the protective film 14 when ions or excited particles of the sealed gas enter the protective film 14. It depends greatly on the easiness of secondary electrons.

  Conventionally, various proposals have been made for a method of manufacturing an MgO film for reducing the discharge voltage, but the proposal mainly relates to a method for manufacturing an MgO film. Specifically, the relationship between the structure of the MgO film and the discharge voltage is proposed. In addition, the specific film structure that lowers the discharge voltage has not been clarified.

  Therefore, the inventor of the present invention clarifies the specific structure of the MgO film for reducing the discharge voltage. In this embodiment, the MgO film having the film structure for reducing the discharge voltage is used for the protective film 14. Was configured.

  The MgO film used in this example has a defect structure in the film structure, and is formed so that secondary electrons are easily emitted from the MgO film. As described above, defects in which secondary electrons are likely to be emitted mainly include defects such as localized levels. The defect structure containing these localized levels can be revealed by, for example, cathodoluminescence (hereinafter referred to as CL) measurement.

  CL refers to light emitted in the process of recombination of holes generated in the valence band and electrons generated in the valence band of the semiconductor or insulator that is the measurement data by the electron beam irradiation. . This spectroscopic analysis of CL is called CL measurement, and an electronic state such as a defect structure in the material can be analyzed.

  FIG. 3 is a diagram schematically illustrating a CL measurement method. Referring to FIG. 3, in the CL measurement, for example, the surface of a sample 34 such as a substrate on which a MgO film is formed is irradiated with an electron beam from an electron excitation source 30 such as a scanning electron microscope. The irradiated electron beam emits light in the sample 34, and the light beam generated by the emitted light is reflected by the reflection unit 33 and dispersed by the spectroscope 31, and enters a measuring device 32 such as a CCD. .

  Next, examples of CL measurement results of an MgO film including a polycrystalline structure formed by an electron beam evaporation method are shown in FIGS.

  In this case, the conditions for the CL measurement are as follows. The electron beam acceleration voltage was 5 kV, the temperature was room temperature, the electron beam incident diameter was 30 nm or less, and the 100 μm square of the measurement object was scanned. Further, in order to obtain conduction, 3-5 nm of Pt was sputter-deposited on the surface of the MgO film. The sample current was 0.17 nA, and the slit width of the spectrometer was 250 μm.

Further, the MgO film used for the measurement shown in FIGS. 4A to 4C is formed by an electron beam evaporation method, and the film formation conditions in this case are as follows. The pressure is 3.0 × 10 ⁻⁴ Torr or less, the substrate temperature T is 250 ° C. <T <350 ° C., the deposition rate is 0.5 to 1.0 nm / sec, the film thickness is 800 nm, and the formed MgO purity is 99. 99%. The MgO film formed in this manner mainly has a polycrystalline structure, and may partially include an amorphous structure. 4A to 4C, the oxygen partial pressure of the atmosphere during film formation is changed by changing the amount of oxygen introduced during film formation. In the case of no oxygen introduction (oxygen partial pressure of approximately 0), in the case of FIG. 4B, the oxygen partial pressure is 0.04 mTorr, and in the case of FIG. 12 mTorr.

Referring to FIGS. 4A to 4C, peaks are observed between 300 nm to 600 nm of the wavelength of CL measurement, and more specifically, spectra are respectively in the ranges of 350 mm to 450 nm and 450 nm to 550 nm. The peak is observed. The peak observed at 350 nm to 450 nm is a localized level called F ⁺ center in which one electron is trapped in the oxygen vacancy of MgO, and the peak observed at 450 nm to 550 nm is the oxygen vacancy of MgO. It is considered to be a localized level called F center in which two electrons are trapped. (GHRosenblart, MWRowe, GPWilliams, Jr., and RTWilliams,
phys. Rev. B36, 10309 (1989)).

When such a defect structure including a localized level such as F ⁺ center or F center is increased in the MgO film, secondary electrons are likely to be emitted from the surface of the MgO film. For example, Xe ions are emitted from the MgO film. It is presumed that the secondary electron gain when incident on the surface is improved and the discharge voltage is lowered. This is considered to be because the condition of Ei> 2ξ is satisfied, where Ei is the ionization energy of Xe ions incident on the MgO surface, where ξ is the energy from the highest localized level to the vacuum level. It is done. (Auger neutralization theory) (HD Hagstrum, “Theory
of Auger neutralization of ions at the surface of a diamond-type semiconductor, ”
Phys. Rev., vol. 122, no.1, pp. 83-113, 1961.)
FIG. 5 is a diagram showing a result of examining a discharge start voltage by forming a PDP having the structure shown in FIG. 2 using the MgO film shown in FIGS. 4A to 4C as a protective film. is there. In FIG. 5, the results shown in Experiments E1 to E3 correspond to the cases shown in FIGS. 4A to 4C, respectively. In addition, the horizontal axis represents the partial pressure of Xe in the sealed gas sealed in the discharge space, and the dependence of the discharge start voltage on the partial pressure of Xe is also examined. The conditions for driving the PDP are as follows. A rectangular wave voltage of 20 kHz and a time ratio of 1/5 was applied to the display electrodes formed in a pair, and measurement was performed after aging driving for 10 hours. When the applied voltage was increased from the state where the discharge was stopped, the voltage at which the discharge started was defined as the discharge start voltage.

  Referring to FIG. 5, in the case of Experiment E1, that is, when the defect structure such as the localized level is the smallest in the MgO film, the discharge start voltage is the highest, and the defect structure such as the localized level is present in the MgO film. It can be seen that as the voltage increases, the discharge start voltage is kept low. For example, when the partial pressure of Xe is 10 kPa, the discharge start voltage is 360 V in the case of Experiment E1, whereas it is 300 V in the case of Experiment E2, 250 V in the case of Experiment E3, and MgO. It can be seen that the discharge start voltage is suppressed as the content of the localized level in the film is increased. Further, when the Xe partial pressure is increased to 20 kPa, the discharge start voltage is 440 V in the case of Experiment E1, whereas it is 350 V in the case of Experiment E2, and 300 V in the case of Experiment E3. Thus, it has been clarified that the effect of suppressing the discharge start voltage is large when the Xe partial pressure is increased. This indicates that the effect of suppressing the discharge start voltage is increased when the Xe partial pressure is increased to increase the brightness and definition of the PDP.

  In addition, the method for increasing the content of defect structures such as localized levels in the MgO film is limited to a method for increasing the partial pressure of oxygen when forming the MgO film by vapor deposition. is not. For example, substrate temperature control and vapor deposition rate control, ion irradiation to the MgO surface after film formation, etc. may be performed. In these cases, the local level in the MgO film is increased, and the discharge start voltage is increased. It becomes possible to suppress.

  Further, the method of forming the MgO film is not limited to the electron beam evaporation method. For example, an ion plating method, a sputtering evaporation method, a pulse laser deposition method (PLD method), etc. are also used as in the case of this embodiment. It is possible to form an MgO film having the above effects.

  Further, when examining the defect structure in the MgO film, it is difficult to calculate the absolute amount of the defect structure. Therefore, it is considered that it is possible to calculate the relative increase / decrease of the defect structure content in the MgO film by comparing the content of the MgO film to be measured with the reference defect structure of MgO. .

  When such a reference MgO is formed, the reproducibility of the crystal structure is preferably high, and the structure is preferably stable. As described above, MgO that can be formed with a reproducible crystal structure includes single crystal MgO having a single crystal structure. For example, a MgO film including a polycrystalline structure or an amorphous structure to be measured has a defect structure. It is considered to be a standard for examining the content rate.

  For example, since single crystal MgO has a high melting point, it is generally formed by an electrofusion method, and a stable crystal with good reproducibility can be obtained.

Next, the results of CL measurement of single crystal MgO are shown in FIG. In this case, the single crystal MgO used was a plate having a thickness of 0.25 mm. Referring to FIG. 6, in the case of single crystal MgO, the above F ⁺ center, F center, etc. are formed on the MgO film including the polycrystalline structure formed by the vapor deposition method shown in FIGS. It is significantly less than that. This indicates that there are few oxygen vacancies in the single crystal MgO.

  Therefore, relatively high electron beam acceleration is necessary for CL measurement of single crystal MgO, but when comparing MgO of thin film and CL results, comparison is made with an electron beam acceleration that does not allow electrons to penetrate the MgO thin film. There must be. Therefore, in the measurement shown in this figure, CL measurement is performed under the same conditions as those of the MgO film shown in FIGS. 4A to 4C and the electron beam acceleration voltage is 5 kV.

  Here, the integrated value of the spectrum intensity of the CL measurement with respect to the wavelength is defined as the area intensity. 7 shows the area intensity at a wavelength of 300 nm to 600 nm in the CL measurement shown in FIGS. 4A to 4C with respect to the area intensity at a wavelength of 300 nm to 600 nm in the CL measurement of the single crystal MgO shown in FIG. The change in the discharge start voltage corresponding to the change in the ratio of the area intensity is shown.

  Referring to FIG. 7, it can be seen that the discharge start voltage decreases as the area intensity ratio increases. In addition, this tendency was observed for the partial pressure of Xe of the sealed gas in the discharge space in any of 13 kPa, 20 KPa, and 27 KPa, and the area intensity ratio was increased particularly when the partial pressure of Xe was large. It has been confirmed that the effect of suppressing the discharge start voltage by is large.

  In particular, when the area intensity ratio is 14 times or more, the discharge start voltage is minimized, and therefore, the discharge start voltage is at least 10 V lower than that of the prior art, and the effect of lowering the discharge start voltage is great.

  Further, when the area intensity ratio is further increased, the effect of lowering the discharge start voltage converges, and when the area intensity ratio is further increased, the resistance of the film to sputtering or the like becomes weaker. For this reason, the upper limit of the area intensity ratio is preferably about 20 times.

  Further, since the area intensity ratio is presumed to indicate the content level of the localized level, the preferable range of the area intensity ratio indicates the preferable range of the content ratio of the localized level it is conceivable that. Therefore, it is preferable that the content level of the local level of the MgO film constituting the protective film 14 is 14 to 20 times the content level of the local level of the single crystal MgO.

  Next, an outline of a method for producing a PDP according to the present embodiment is shown below. However, in the figure, the same reference numerals are given to the parts described above, and the description will be omitted.

  First, a laminated film made of a transparent conductive film and chromium (Cr) / copper (Cu) / Cr (chromium) is formed on the front plate 11 made of a glass substrate by a sputtering method.

  Next, the transparent conductive film and the laminated film are formed into a strip-like pattern with a thickness of 170 μm and the laminated film of 55 μm, respectively, using a photolithography technique, and the display electrode 12 is obtained.

  Next, a low melting point glass paste is printed on the front plate 11 on which the display electrode 12 is formed, dried, and then fired to form the dielectric layer 13 having a thickness of about 20 μm. .

Next, a protective film 14 made of an MgO film is formed by electron beam evaporation so as to cover the dielectric layer 13 under the following conditions. The pressure is 3.0 × 10 ⁻⁴ Torr or less, the substrate temperature T is 250 ° C. <T <350 ° C., and the oxygen partial pressure p in the film formation atmosphere is 1.0 × 10 ⁻⁴ Torr <p <2.0. × 10 ⁻⁴ Torr. Under these conditions, an MgO film having a thickness of 800 nm is formed at a deposition rate of 0.5 to 1.0 nm / sec, and the formed MgO purity is 99.99%.

  Next, a photosensitive silver paste is formed in a strip pattern using a photolithography technique at a desired position on the back plate 15 made of a glass substrate, thereby forming the data electrode 16 made of silver. The dielectric layer 17 is formed to cover the data electrode 16.

Further, the partition wall 18 having a width of 60 μm and a height of 130 μm was formed on the dielectric layer 17, and the phosphor 19 was applied on the surfaces of the partition wall 18 and the dielectric layer 17. Wherein the phosphor 9, for example, a red light emitter _{((Y x Gd 1-x} ) BO 3: Eu 3+), green light-emitting body (BaAl ₁₂ O _19: Mn) and blue emitter (BaMgAl ₁₄ O _23: Eu ²⁺ ).

  Next, the front plate 11 and the back plate 15 are bonded together so that the display electrode 12 and the data electrode 16 are orthogonal to each other, the periphery is sealed with glass frit, and the discharge space 20 is exhausted. The discharge space 20 is filled with a sealed gas composed of a Ne—Xe mixed gas containing 5% to 30% of Xe so that the pressure in the discharge space is 400 Torr or more and 650 Torr or less.

  Thus, the PDP shown in FIGS. 1A and 1B and FIG. 2 can be manufactured.

  In this embodiment, an example of an AC drive type PDP has been shown. However, the present invention is not limited to an AC drive type, and can be applied to, for example, a DC drive type or an AC / DC hybrid drive type. Thus, it is possible to obtain the same effects as those described in this embodiment, and it is possible to realize a PDP having a low drive voltage and high brightness and high definition.

(A), (B) is sectional drawing which showed typically PDP by Example 1. FIG. It is the perspective view which showed typically PDP by Example 1. FIG. It is a figure which shows the outline | summary of a cathodoluminescence measurement. (A)-(C) are the figures which showed the result of the cathodoluminescence measurement of the MgO film | membrane formed by the vapor deposition method. It is the figure which showed the discharge start voltage with respect to the partial pressure of Xe of discharge space. It is the figure which showed the result of the cathodoluminescence measurement of single crystal MgO. It is a figure which shows the effect of a present Example.

Explanation of symbols

10 PDP
DESCRIPTION OF SYMBOLS 11 Front plate 12 Display electrode 13 Dielectric layer 14 Protective film 16 Data electrode 17 Dielectric layer 18 Bulkhead 19 Phosphor 20 Discharge space 30 Excitation source 31 Spectrometer 32 Detector 33 Reflection part 34 Measurement sample

Claims (3)

A first substrate;
A second substrate facing the first substrate;
A first electrode formed on a side of the first substrate facing the second substrate;
A second electrode formed on a side of the second substrate facing the first substrate;
A first dielectric layer formed to cover the first electrode;
A second dielectric layer formed to cover the second electrode;
A protective film made of an MgO film including a polycrystalline structure formed to cover the first dielectric layer;
A plasma display panel having a discharge space formed between the protective film and the second dielectric layer,
The plasma display panel, wherein the protective film has a localized level of MgO, and the content of the localized level is larger than the content of the localized level of single crystal MgO. A first substrate;
A second substrate facing the first substrate;
A first electrode formed on a side of the first substrate facing the second substrate;
A second electrode formed on a side of the second substrate facing the first substrate;
A first dielectric layer formed to cover the first electrode;
A second dielectric layer formed to cover the second electrode;
A protective film made of an MgO film formed to cover the first dielectric layer;
A plasma display panel having a discharge space formed between the protective film and the second dielectric layer,
The protective film has a localized level of MgO, and the content of the localized level is 14 to 20 times the content of the localized level of single crystal MgO. panel. A first substrate;
A second substrate facing the first substrate;
A first electrode formed on a side of the first substrate facing the second substrate;
A second electrode formed on a side of the second substrate facing the first substrate;
A first dielectric layer formed to cover the first electrode;
A second dielectric layer formed to cover the second electrode;
A protective film made of an MgO film formed to cover the first dielectric layer;
A plasma display panel having a discharge space formed between the protective film and the second dielectric layer,
A plasma display panel, wherein the protective film has an area intensity ratio in a wavelength range of 300 nm to 600 nm of a spectral characteristic of cathodoluminescence measurement with respect to an MgO single crystal film of 14 times to 20 times.

Images