CN1965385A - Gas discharge display panel - Google Patents

Abstract

A first object of the present invention is to provide a gas discharge display panel which is low in cost, can maintain a wall charge holding power, can control a discharge lag in a region optimal for image display, and can exhibit a good display performance by lowering a discharge start voltage. Further, a second object of the present invention is to provide a PDP and a method of manufacturing a gas discharge display panel, in which the PDP further improves the 2-time electron emission coefficient γ than before, reduces the discharge start voltage to expand the driving margin, thereby improving the display quality and reliability; the manufacturing method of the gas discharge display panel shortens the exhaust time in the sealing exhaust process to reduce the manufacturing cost and reduce the cost of the driving circuit. In the present invention, a protective layer (15) is composed of a 1 st protective film (151) formed on the surface of a dielectric layer (14) and a 2 nd protective film (152) laminated on at least a part of the surface of the 1 st protective film (151), and the 1 st protective film (151) is configured to contain more impurities than the 2 nd protective film (152).

Description

Gas discharge display panel

Technical field

The present invention relates to gas discharge display panels such as plasma display, relate to the improving technology of protective layer.

Background technology

Gas discharge display panel is as the plasma display of its representative (below be called PDP), is the display unit of utilizing the ultraviolet ray exited light-emitting phosphor that produced by gas discharge to come display image.According to the formation method of its discharge, PDP can be divided into interchange (AC) type and direct current (DC) type, and the AC type is more superior than DC type at aspects such as brightness, luminous efficiency and life-spans, so this type is the most general.

AC type PDP is for example disclosed as patent documentation 1, have following structure: the surface of 2 thin face glasss that makes a plurality of electrodes (show electrode or addressing electrode) and disposed dielectric layer in the mode that covers this electrode is every a plurality of spaced walls and opposed, between these a plurality of spaced walls, dispose fluorophor, discharge cell is formed rectangular, under this state, between two panels glass, enclose discharge gas.Surface at the dielectric layer that covers show electrode forms protective layer (film).

PDP is when driving, according to so-called interior timesharing gray scale display mode, in a plurality of son (during comprising initialization, address period, during keeping etc.), above-mentioned a plurality of electrodes suitably to be powered, the ultraviolet ray that utilizes the discharge gas discharge to be produced makes light-emitting phosphor.

Here, the material for the protective layer of the face glass of front face side requires to have in the ion bombardment when the protection dielectric layer makes it avoid discharging, the function of discharging with low discharge ionization voltage.For reaching this purpose, as disclosed in the patent documentation 2, be extensive use of with have superior anti-sputter, 2 big magnesium oxide (MgO) of electron emission coefficiency are the protective layer of the material of main component as PDP.

But there is following problem in existing protective layer.

As first problem, the problem of what is called " discharge lag " is arranged in existing protective layer.This is to be equivalent in address period from electrode being applied the phenomenon of the time deviation till the pulse that is used for address discharge begins to produce discharge to reality, when discharge lag is big, do not become big even do not produce the probability of address discharge in the moment that addressing pulse applies end yet, be easy to generate write bad.The easy more generation in high-speed driving of this situation.In order to obtain good PDP image display performance, should solve the problem of this discharge lag.

Therefore, as the countermeasure of discharge lag, for example, in patent documentation 3 and 7, seek to shorten the technology of this hysteresis by the Si that MgO is added ormal weight.In addition, in patent documentation 4, the technology that shortens this hysteresis by the H that protective layer is added ormal weight is disclosed.And then, in patent documentation 5, the technology that shortens this hysteresis by interpolation Ge is disclosed.

Secondly, second problem is the problem of the characteristic variations of protective layer.

That is, though the surface of protective layer be exposed in the discharge space,, metal oxide films such as above-mentioned MgO film have adsorbed water (H ₂O) or carbon dioxide (CO ₂) wait gas to form the character of oxyhydroxide or carbonate compound easily.In the processing in the atmosphere of PDP manufacturing process, because of oiliness impurity or the CO in the atmosphere ₂, H ₂The absorption of O etc., the protective layer that is made of MgO has easy contaminated tendency.When the above-mentioned adsorbed gas of MgO surface adsorption etc., the characteristic of protective layer changes, and 2 times electronic transmitting efficiency descends.As a result, exist discharge ionization voltage to rise the problem that the driving margin of PDP is narrow.

And then because of the dispersion that protective layer produces the discharge ionization voltage of discharge cell to the difference of the degree of absorption of above-mentioned gas etc., thus, existence can not correctly make the problem of the unit display defect that show, that be referred to as black noise that will show.

Therefore, in the past, shown in patent documentation 6, proposed to come desire to improve the scheme of performance and raising stability by protective layer being designed to 2 layers of structure.Specifically, disclose a kind of 2 layers of structure, it has carried out preferably in flash-over characteristic being provided with on first diaphragm of (111) orientation and has had the second membranous diaphragm that is difficult for adsorbed gas, moisture absorption difference, thus, can prevent hydrone or CO ₂Absorption etc. foreign gas.

Patent documentation 1: the spy opens flat 9-92133 communique etc.

Patent documentation 2: the spy opens flat 9-295894 communique

Patent documentation 3: the spy opens flat 10-334809 communique

Patent documentation 4: the spy opens the 2002-33053 communique

Patent documentation 5: the spy opens the 2004-31264 communique

Patent documentation 6: the spy opens the 2003-22755 communique

Patent documentation 7: the spy opens the 2004-134407 communique

But,, also enough hardly at present about countermeasure as the discharge lag of above-mentioned first problem.

Specifically, as can be known in the technology of patent documentation 3, by MgO is added Si, the generation that can suppress not put bright area to a certain extent but then, produces again and makes the dispersed new problem that obviously increases of discharge lag time in each unit.

In addition, in the technology of patent documentation 4, can suppress discharge lag by MgO is added H, still, present inventor's result of study shows that the hold facility of wall electric charge descends, and is difficult to produce the needed optimal discharge of display image.

And then in the technology of patent documentation 5, according to determination experiment as can be known, the effect that suppresses discharge lag is insufficient, and discharge ionization voltage has been risen, and is obtaining to have effect of sufficient aspect the excellent display performance hardly.

In order to solve the problem of such a protective layer; consideration is in the operating voltage that improves PDP, to the method for drive circuit and integrated circuit use high-voltage transistor or driver IC etc., still; owing to except increasing power consumption, also improved the cost of PDP, so inadvisable.

And then, as above-mentioned second problem, also there is following problem.

In above-mentioned prior art 2, when being exposed to material in the atmosphere in PDP manufacturing process, protective layer can CO absorption ₂Or unwanted composition such as water, the characteristic of protective layer changes sometimes.Therefore, the problem that exist 2 electronic transmitting efficiencies of protective layer to reduce, discharge ionization voltage rises, the driving margin of PDP narrows down.

And then; in the technology of patent documentation 6; though 2 electronic transmitting efficiencies and the discharge ionization voltage to the protective layer of these 2 layers of structures not disclose, 2 electron emission coefficiency γ can be estimated as value the highest and about 0.2 left and right sides par that protective layer obtained that is made of MgO by existing 1 layer of structure.Therefore, can infer discharge ionization voltage also has and passes by same higher value.

And then, also there is such problem, if the characteristic of such protective layer changes, can produce the dispersiveness of discharge ionization voltage when then PDP drives, produce the display defect that is referred to as black noise, display quality and reliability are exerted an influence.

As its countermeasure, in order before enclosing discharge gas, to remove the CO of attachment removal ₂With gas such as water, consider to carry out vacuum exhaust technology, still, PDP has the interstitial structure that approaches that is formed by the relative configuration with rear board of front panel, so the exhaust gas inside conductance is very little.Therefore, this arts demand carries out the processing of long period, can produce the other problems relevant with the technology cost.

As mentioned above, for gas discharge panel, also leave over the problem that should solve.

Summary of the invention

The present invention makes in view of above-mentioned problem, its first purpose is to provide a kind of gas discharge display panel, its cost is lower and can keep the confining force of wall electric charge, discharge lag can be controlled at simultaneously image is shown in the only zone, and then, by reducing discharge ionization voltage, can bring into play good display performance.

In addition, second purpose of the present invention is to provide the manufacture method of a kind of PDP and gas discharge display panel, and wherein, PDP makes 2 electron emission coefficiency γ than further improved in the past, reduce discharge ionization voltage with the expansion driving margin, thereby improved display quality and reliability; The manufacture method of gas discharge display panel, the evacuation time when shortening the sealing deairing step are with the reduction manufacturing cost, and the cost of reduction drive circuit.

In order to solve above-mentioned problem; the present invention is a kind of gas discharge display panel that the surface stacks gradually the panel of dielectric layer and protective layer that possesses; wherein; above-mentioned protective layer possesses the 1st diaphragm that forms and at the 2nd stacked diaphragm of at least a portion zone on the surface of above-mentioned the 1st diaphragm on the surface of above-mentioned dielectric layer; and above-mentioned the 1st diaphragm is to compare the structure that contains more impurity with above-mentioned the 2nd diaphragm.

At this, also can be that above-mentioned the 2nd protective film builds up the whole surface that covers above-mentioned the 1st diaphragm.

In addition, also can be that above-mentioned the 2nd protective film builds up at least a portion surface of exposing above-mentioned the 1st diaphragm under the above-mentioned show electrode.

In addition, also can be for above-mentioned the 2nd diaphragm, the ratio that this above-mentioned the 2nd diaphragm occupies the area of above-mentioned the 1st diaphragm under the above-mentioned show electrode is more than 10% and 90% following area occupation ratio.

At this, specifically, the thickness of above-mentioned the 2nd diaphragm can be more than the 10nm and below the 1 μ m, and the thickness of above-mentioned the 2nd diaphragm can be more than the 10nm and below the 100nm.

And then, also can be that the above-mentioned impurity of sneaking into above-mentioned the 1st diaphragm is at least a kind the impurity that contains among H, Cl, F, Si, Ge, the Cr.

And then, also can be that the content of the above-mentioned impurity in above-mentioned the 1st diaphragm is in the scope that 10ppm is above and 10000ppm is following.

In addition, also can be above-mentioned the 1st diaphragm and above-mentioned the 2nd diaphragm to comprise the mode film forming of at least a kind of metal oxide materials among MgO, CaO, BaO, SrO, MgNO and the ZnO.

In addition, also can be that any one of above-mentioned the 1st diaphragm and above-mentioned the 2nd diaphragm is all to comprise the mode film forming of MgO.

Perhaps, also can be that above-mentioned the 1st diaphragm comprises BaO and film forming, above-mentioned the 2nd diaphragm comprise MgO and the combination of film forming.

In addition; the present invention is a kind of manufacture method of gas discharge display panel; it has the operation that is formed into the show electrode that forms on the 1st substrate; form the operation of the dielectric layer that covers above-mentioned show electrode and form; the protective layer that is formed on the protective layer that the surface of above-mentioned dielectric layer forms forms operation; and above-mentioned the 1st substrate is separated with the operation that disposes the 2nd substrate with gap in opposite directions; wherein; above-mentioned protective layer formation operation is not exposed to by the 1st diaphragm that will contain many impurity on the surface of above-mentioned dielectric layer comes film forming in the atmosphere; and at least a portion on the surface of above-mentioned the 1st diaphragm, the 2nd diaphragm is not exposed to come in the atmosphere stacked, thereby form protective layer.

At this, also can be that above-mentioned protective layer forms operation and utilizes sputtering method to make at least one side's film forming among above-mentioned the 1st diaphragm and above-mentioned the 2nd diaphragm.

The effect of invention

According to PDP of the present invention; as protective layer; possesses the 1st diaphragm that contains above-mentioned impurity and the 2nd stacked diaphragm on its surperficial at least a portion zone; and the 1st diaphragm contain the more impurity of volume than the 2nd diaphragm; by constituting protective layer by this way; can reduce the absorption of gas protected seam in the processing under the atmosphere thus; and reduce discharge ionization voltage widening driving margin, thereby can not produced the display quality of display defect such as black noise and the PDP that reliability improves.

In addition; manufacture method according to PDP of the present invention; as protective layer; by containing than the 2nd diaphragm after more the 1st diaphragm film forming of volume impurity forms making; on the lip-deep at least a portion of the 1st diaphragm, be not exposed in the atmosphere film forming form the 2nd diaphragm, thereby the evacuation time can obtain shortening the sealing deairing step that PDP makes the time is to reduce manufacturing cost and can reduce the manufacture method of the PDP of drive circuit cost.

Description of drawings

Fig. 1 is the sectional stereogram that schematically shows the structure of the PDP in the execution mode 1.

Fig. 2 is the figure of example of the driving process of expression PDP.

Fig. 3 is the curve chart of the relation of expression composition of protective layer and discharge dispersity (discharge variability).

Fig. 4 is the curve chart of the detailed relation of expression composition of protective layer and discharge dispersity.

Fig. 5 is the curve chart of the relation of the expression composition of protective layer and discharge lag and wall electric charge confining force index.

The curve chart of the relation of Fig. 6 emission wavelength that to be expression produced by cathodoluminescence and luminous intensity.

Fig. 7 is the curve chart of the relation of expression discharge dispersity and the luminous intensity that produced by cathodoluminescence.

Fig. 8 is the curve chart of the relation of expression discharge ionization voltage and the luminous intensity that produced by cathodoluminescence.

Fig. 9 is the cross-sectional conceptual figure of the protective layer periphery of the PDP in the expression execution mode 2.

Figure 10 (a) is the cross-sectional conceptual figure of structure of the front panel of the discharge cell of expression in the execution mode 2, (b) is the plane concept map of (a).

Figure 11 (a) is the cross-sectional conceptual figure of structure of the front panel of another embodiment of expression in the execution mode 2, (b) is the plane concept map of (a).

Figure 12 is the figure that the expression protective layer is placed on the difference of the adsorbance in the atmosphere.

Symbol description

1PDP

10 front panels

11 front panel glass

12 scanning (Scan) electrodes

13 keep (Sustain) electrode

14,19 dielectric layers

15 protective layers

16 rear boards

17 rear board glass

18 addressing electrodes

20 spaced walls

23 luminescent coatings

31,32 discharge cells

33 show electrodes

34,35,36,37 protective layers

121,131 bus electrodes

151,152 the 1st diaphragms

153,154 the 2nd diaphragms

Embodiment

Below, with reference to the description of drawings embodiments of the present invention.

＜execution mode 1 〉

1-1.PDP structure

Fig. 1 is that stereogram cuts open in the office of primary structure of the AC type PDP1 of expression embodiment of the present invention 1.Among the figure, the z direction is equivalent to the thickness direction of PDP1, and the xy plane is equivalent to the plane parallel with the panel face of PDP1.PDP1 as 1 example, adopt the standard of the NTSC standard that meets 42 inches grades, yet the present invention also is applicable to other standards and sizes such as XGA or SXGA certainly at this.

As shown in Figure 1, the structure of PDP1 is roughly divided into front panel 10 and the rear board 16 that interarea is disposed mutually in opposite directions.

On an interarea of the front panel glass 11 of the substrate that becomes front panel 10, form many to show electrode 12,13 (scan electrode 12, keep electrode 13).Each show electrode the 12, the 13rd is layered in the bus 121,131 (thickness 7 μ m, width 95 μ m) by Ag thick film (thickness 2 μ m～10 μ m), aluminium (Al) film (thickness 0.1 μ m～1 μ m) or Cr/Cu/Cr laminate film formations such as (thickness 0.1 μ m～1 μ m) by ITO or SnO ₂Form on the banded transparency electrode 120,130 (thickness 0.1 μ m, width 150 μ m) Deng transparent conductivity material formation.Utilize this bus 121,131 that the sheet resistor of transparency electrode 120,130 is descended.

On the front panel glass 11 that has disposed show electrode 12,13, the whole interarea that spreads all over this glass 11 forms with lead oxide (PbO) or bismuth oxide (Bi with silk screen print method etc. ₂O ₃) or phosphorous oxide (PO ₄) be the dielectric layer 14 of the low-melting glass (thickness 20 μ m～50 μ m) of main component.Dielectric layer 14 has the distinctive current limit function of AC type PDP, and PDP compares with the DC type, becomes the key element that realizes long lifetime.On the surface of dielectric layer 14, the protective layer 15 of the about 1.0 μ m of applied thickness.

Herein, present embodiment 1 is characterised in that the structure of protective layer 15, and the back will elaborate to it.

On an interarea of the rear board glass 17 of the substrate that becomes rear board 16, to be a plurality of addressing electrodes 18 of 60 μ m by the width of Ag thick film (thickness 2 μ m～10 μ m), aluminium (Al) film (thickness 0.1 μ m～1 μ m) or Cr/Cu/Cr laminate film formations such as (thickness 0.1 μ m～1 μ m), with the x direction be long side direction the y direction at regular intervals (360 μ m) be arranged side by side into strips, with the mode of this addressing electrode 18 of the interior bag dielectric film 19 that to spread all over whole applied thickness of rear board glass 17 be 30 μ m.

On dielectric film 19 and then the gap configuration spaced walls 20 of the addressing electrode 18 of aligned abutment (highly about 150 μ m, the about 40 μ m of width), distinguish cell S U with the spaced walls 20 of adjacency, its effect is the generation that misplaces electricity and optical crosstalk that prevents the x direction.Then, the side of 2 spaced walls 20 of adjacency and between the face of dielectric film 19 on form and correspond respectively to the luminescent coating 21～23 that shows the redness (R) of usefulness, green (G), blue (B) for colored.

Have again, also can be without dielectric film 19 directly with bag addressing electrode 18 in the luminescent coating 21～23.

Front panel 10 and rear board 16 are disposed opposite to each other in the mode of addressing electrode 18 with the mutual long side direction quadrature of show electrode 12,13, with the outer peripheral portion of frit-sealed two panels 10,16.Pressure (being generally about 53.2kPa～79.8kPa) with regulation between this two panels 10,16 is enclosed the discharge gas (inclosure gas) that is made of inert gas compositions such as He, Xe, Ne.

Be discharge space 24 between the spaced walls 20 of adjacency, the zone that adjacent a pair of show electrode 12,13 intersects with 1 addressing electrode, 18 clamping discharge spaces 24 is corresponding with unit (being also referred to as " the sub-pixel ") SU of image demonstration.Unit interval is 1080 μ m in the x direction, is 360 μ m in the y direction.Constitute 1 pixel (1080 μ m * 1080 μ m) by three cell S U of adjacent RGB.

1-2.PDP driving method

The PDP of said structure is applied the AC voltage of tens of kHz～hundreds of kHz in the gap of a pair of show electrode 12,13 by not shown drive division, drive thus, make in the cell S U and discharge, send visible light by ultraviolet ray excited luminescent coating 21～23 from the Xe atom that is excited.

As the example of this driving method, there is timesharing gray scale display mode in so-called.This mode is divided into a plurality of sons with field to be shown, so with each son field be divided into a plurality of during.In each son field, after the wall electric charge initialization (resetting) with whole image during the initialization, make the wall electric charge only accumulate address discharge in the discharge cell that should light in address period, during discharge is thereafter kept, by whole discharge cells being applied simultaneously alternating voltage (keeping voltage), keep constant time discharge, to carry out luminous demonstration.

When this drives,, will for example be divided into 6 son fields from each F that the input picture of outside is promptly arranged in chronological order with above-mentioned drive division for by the luminous 2 values control of carrying out on/off in each unit is come representing gradation.The relative ratios of the brightness in each son field is for example to get 1: 2: 4: 8: 16: 32 mode weighting, set sub fully the number of light emission times of keeping (keeping discharge).

Herein, Fig. 2 is an example of the drive waveforms process of this PDP1.The drive waveforms of m son field in the field has been shown in this Fig. 2.As shown in Figure 2, during each son field is assigned to initialization respectively, address period, discharge keep during, between erasing period.

During the so-called initialization, be meant the influence that causes for lighting of the unit before preventing thus (influence that causes by the wall electric charge of being accumulated), carry out whole image the wiping of wall electric charge (initialization discharge) during.In this waveform example shown in Figure 2, whole show electrodes 12,13 are applied reset pulse above the waveform that has a down dip of the positive polarity of discharge ionization voltage Vf.Meanwhile, in order to prevent the charged and ion bombardment of rear board 16 sides, whole addressing electrodes 18 are applied positive pulse.Utilization applies the differential voltage of the rising edge and the trailing edge of pulse, and producing the plane of weakness discharge in whole unit is the initialization discharge, is all accumulating the wall electric charge in the unit, and whole image forms uniform electriferous state.

Address period be according to be divided into the son picture signal and to selecteed unit carry out addressing (setting of lighting/not lighting) during.In this period, scan electrode 12 is biased to positive potential with respect to earthing potential, whole electrodes 13 of keeping is biased to negative potential.Under this state, the top line from panel top (unit of horizontal row corresponding with a pair of show electrode) selects each capable successively line by line, and the scanning impulse of negative polarity is applied on the corresponding scan electrode 12.In addition, the addressing electrode 18 of the unit correspondence lighted of Xiang Yuying applies the addressing pulse of positive polarity.Thus, take over the weak face discharge during above-mentioned initialization, only carry out address discharge, accumulate the wall electric charge in the unit that should light.

Discharge during keeping be enlarge in order to ensure the brightness corresponding with gray scale the illuminating state set by address discharge with keep discharge during.Herein, in order to prevent unwanted discharge, whole addressing electrodes 18 all are biased to the current potential of positive polarity, to all keeping the pulse of keeping that electrode 13 applies positive polarity.To scan electrode 12 with keep electrode 13 alternately apply keep pulse, in specified time limit repeatedly discharge thereafter.

Between erasing period, scan electrode 12 is applied the pulse that weakens gradually, make the wall charge erasure thus.

Having, have nothing to do with the length of address period and the weight of brightness during the initialization, be constant, but the weight of brightness is big more, and the length during discharge is kept is just long more.That is to say that the length during the demonstration of each son field is different.

In PDP1, utilize each discharge of in son, being carried out, generation is by resulting from the having the resonance line of spike at the 147nm place and be the vacuum ultraviolet that the molecular line at center constitutes with 173nm of Xe.This vacuum ultraviolet shines on each luminescent coating 21～23, produces visible light.Then, utilize the combination of a RGB unit of all kinds, can carry out polychrome and many gray scales and show.

Herein, present embodiment 1 is characterised in that the structure of the protective layer 15 among the PDP1.Protective layer 15 in the present embodiment 1 is a main component with MgO, and by contain more than the 20 quality ppm and the Si of the addition scope below the 5000 quality ppm and more than the 300 quality ppm and the H of the addition scope below the 10000 quality ppm constitute as impurity (additive).According to the structure of the protective layer 15 that contains this impurity of ormal weight, in PDP1,, receive and suppress the effect that discharge lag takes place from protective layer emission the contributive electron number that discharges is increased.In addition, on this basis, if discharge lag takes place, the effect of the dispersiveness of each discharge lag time that also can be inhibited can realize remarkable image display performance.

Below, describe this characteristic in detail.

＜about the feature and the effect of execution mode 1 〉

In general; in PDP; address period when driving is because based on the problem that writes defective of discharge lag, often be difficult to obtain suitable image and show; but in PDP of the present invention; as mentioned above, to constituting the MgO of protective layer, add H in right amount; perhaps add Si or Ge on this basis more in right amount, thereby can address this problem effectively.

Promptly; in the present invention; by promote emission by said structure to the contributive electronics that discharges from protective layer; thereby make being suppressed of discharge lag; on the other hand by keeping the confining force of wall electric charge; thereby can suppress to write the generation of defective, and can normally carry out normal address discharge and follow-up keep discharge, can obtain the preferable image display performance.

In addition, in the present invention, even, compare with existing situation if when driving, taken place under the situation of discharge lag, the dispersiveness (discharge dispersity) that also can suppress the discharge lag time in each unit obtains the effect that the degree of this discharge dispersity averages out.Like this, by slowing down discharge dispersity, in the present invention, by the measures such as constant time lag stipulated time that the pulse of taking for example to make address period on whole front panel applies, brought into play the effect that can effectively prevent the generation that writes defective that causes because of discharge lag by leaps and bounds.

Therefore, in PDP1 of the present invention, owing to can realize reliable addressing, so, also can carry out addressing with good probability even correspondingly reduce the pulse duration that applies of address period slightly.Thus, even unlike existing, adopt two scan modes, also can carry out good driving with the type of drive such as so-called single scan mode that the drive IC number can reduce by half.According to this reason, the advantage that the present invention has also brought into play the structure of simplifying drive division and can produce with low cost.

The present invention take into account can so suppress discharge dispersity so that suppress discharge lag and keep wall electric charge confining force aspect, received for example unexistent useful effect in prior aries such as patent documentation 3,4 and 5.Promptly, the present inventor is on the understanding basis of keeping this class problem for inhibition of clearly not seeking that takes into account discharge dispersity and discharge lag and wall electric charge confining force in the past, concentrate on studies repeatedly, found the said structure that should be able to effectively solve this type of problem.

Then, carry out embodiment and performance comparative experiments, the data that obtained by its result are described.

The affirmation experiment of＜embodiment and effect 〉

Fig. 3 is the curve chart of the relative size of expression composition of protective layer and the dispersiveness of discharge lag time (discharge dispersity).In the figure, be 100% with the discharge dispersity of the existing protective layer that only constitutes (comparative example 1) by MgO, the data relevant with the protective layer of the following structure of comparing with it are shown.

Add the protective layer (comparative example 2) of Si: Si is added among the MgO with 100 quality ppm

Add the protective layer (embodiment 1) of Si+H: with 100 quality ppm Si is added among the MgO, and H is added among the MgO with 1000 quality ppm

Add the protective layer (embodiment 2) of H: H is added among the MgO with 1000 quality ppm

According to the data of this Fig. 3, think that at first the protective layer (comparative example 2) that only Si is added among the MgO with less amount is not preferred, because the value of discharge dispersity is up to 114% at this moment, performance worsens on the contrary.This comparative example 2 has the structure that is equivalent to above-mentioned patent documentation 7, from these data as can be known, adopts the technology of this patent documentation 3, in fact is difficult to obtain the preferable image display performance.

On the other hand, in the embodiment 1 (execution mode 1) that the Si of ormal weight and H is added among the MgO, compare with comparative example 1, discharge dispersity can be suppressed to about 31%, can confirm to have the effect with the discharge lag time averageization in a plurality of unit.

In addition; constitute protective layer (embodiment 2) among the MgO even differently only H is added to the amount of strict regulations with execution mode 1; compare with comparative example 1, also can obtain relative value with discharge dispersity and be reduced to effect about 54%, can confirm to obtain effect of the present invention fully.

Next the existing protective layer that the Fig. 4 shown in represents only to be made of MgO (comparative example a, identical) with above-mentioned comparative example 1, with the Si of ormal weight add to wherein comparative example b, c and with ormal weight with H or the intensity of the discharge dispersity of the embodiment d, the e that also have Si to add to form among the MgO, f, g, h.

In this embodiment and comparative example shown in Figure 4; by containing Si with 100 quality ppm and containing the protective layer (embodiment f) that the MgO of H constitutes with 1000 quality ppm is the structure that can obtain the inhibition effect of discharge dispersity; with this embodiment f is basic structure; along with the content that makes Si increases, can confirm the trend (embodiment g, h) that discharge dispersity increases.Therefore, in the present invention,, must stipulate H contained among the MgO rightly or also have the content of Si in order to obtain being higher than the performance of comparative example a.This concrete prescribed limit will be narrated in the back.

From above experimental result as can be known, compared with the past according to structure of the present invention, can expect that the degree that obtains discharge dispersity slowed down more in the past, and make the result of this degree homogenization.Thus, even for example discharge lag has taken place, applying regularly of addressing pulse as one man postponed, with this discharge lag time perhaps by setting pulse duration in address period, also can make and reliably carry out addressing and become possibility, and obtain the preferable image display performance.

Then, Fig. 5 is the composition of expression protective layer and the curve chart of discharge lag (relative value) and wall electric charge confining force index.In the figure, discharge lag and wall electric charge confining force index with picture quality during for the practical level that goes up no problem are set at 1, and with discharge lag be below 1, wall electric charge confining force index is to be set at the picture quality permissible range more than 1.That is, we can say that satisfying discharge lag＜1 and wall electric charge confining force index＞1 is qualified product.Therefore figure 5 illustrates the data relevant with the protective layer of following structure.

Existing MgO (comparative example 1): do not carry out the MgO that impurity adds

Add the MgO (comparative example 2) of H: H is added among the MgO with 2000 quality ppm

Add the MgO (embodiment 1) of H+Ge: with 50 quality ppm Ge is added among the MgO, and H is added among the MgO with 2000 quality ppm

Add the MgO (1) (embodiment 2) of Ge: Ge is added among the MgO with 50 quality ppm

Add the MgO (2) (comparative example 3) of Ge: Ge is added among the MgO with 1000 quality ppm

From the data of Fig. 5 as can be known, at first for only H being added to the protective layer (comparative example 2) that forms among the MgO, though discharge lag is suppressed, wall electric charge confining force has reduced.Therefore think that the protective layer of this structure is not preferred, because its performance worsens on the contrary.This comparative example 2 has the structure that is equivalent to above-mentioned patent documentation 4, from its data as can be known, adopts the technology of this patent documentation 4, in fact is difficult to obtain the preferable image display performance.

On the other hand, in the embodiment 1 (execution mode 1) that the H of ormal weight and Ge is added among the MgO, discharge lag has dropped on image has been shown in the best scope as can be known, and then with regard to wall electric charge confining force, also no problem in practicality.

In addition, constitute protective layer (embodiment 2) among the MgO, also can confirm to obtain effect of the present invention fully even differently only Ge is added to the amount of strict regulations with execution mode 1.

, only the Ge of 1000 quality ppm is being added under the situation of the protective layer (comparative example 3) that forms among the MgO, as can be seen from Figure 5, discharge lag has exceeded the permissible range that is used to obtain preferable image.This means apply addressing pulse during the probability that takes place of address discharge reduced, consequently be easy to write defective.

From above experimental result as can be known, according to structure of the present invention, it is constant and discharge lag is controlled at is suitable for most in the scope that image shows to keep wall electric charge confining force.Consequently, can prevent to write defective, to obtain the preferable image display performance in address period.Have, necessary in the present invention H and the addition of Ge will be addressed in the back again.

Then, for the different protective layer 15 of discharge dispersity, measure the cathodoluminescence when driving, the relation of research peculiar luminescent spectrum of protective layer and discharge dispersity.So-called cathodoluminescence (CL) method detects the luminescent spectrum of the process that relaxes as its energy when being meant the sample irradiation electron beam, thereby obtains the analytic approach of the information of the existence of defective in the sample (protective layer) and structure thereof etc.

Fig. 6 is expression and curve chart to the data of this relevant experimental result of the cathodoluminescence of 4 kinds of samples mensuration, is that to get emission wavelength be that transverse axis, luminous intensity are the curve chart that the longitudinal axis is represented both sides relation.The difference of sample is from top as follows successively.

Sample A:(MgO+Si+H), embodiment

The H of sample B:(MgO+400 quality ppm)

Sample C:(only is MgO)

The Si of sample D:(MgO+1000 quality ppm)

Have, condition determination is as follows again.

Beam voltage: 5kV

Heater current density: 2.4 * 10 ⁸(A/cm ²)

In this Fig. 6, press the order of sample A～D, the relative value of discharge dispersity is 31,74,100,184, and the spectral waveform of each protective layer is shown.In each spectrum, gross examination of skeletal muscle to 3 peak value (being respectively about the about 410nm of emission wavelength, about 510nm and about 740nm).The energy of the defect level that exists in the wavelength value of each peak value and the band gap of protective layer has dependency relation.From this relation as can be known, the peak value of the about 740nm of emission wavelength is big more, just many more to the contributive electron number that discharges from protective layer emission, and the effect of the discharge dispersity that can be inhibited more.

Have, the luminous intensity shown in each waveform is meaningful to its relative value in each curve, and there is not special significance in its absolute value again.

In the protective layer of embodiment (sample A, B), in whole above-mentioned emission wavelengths, tangible peak value appears.Particularly other sample of the peakedness ratio of the about 740nm of emission wavelength (C, D) is big as can be known.Also can infer thus, even in the MgO of protective layer, contain for example Si, if but the amount of Si is improper, then also be difficult to obtain good effect as protective layer.Also can consider to contain the protective layer of H in the same way.

Then, the peak value of the discharge dispersity of the protective layer of cathodoluminescence mensuration shown in Figure 7 and the about 740nm of emission wavelength is with respect to the relation of the relative area intensity of the peak strength of the about 410nm of emission wavelength.The data of representing sample A～D from the little value of the discharge dispersity of transverse axis successively.

The relative area intensity of sample A, B from this Fig. 7 as can be known, for making discharge dispersity less than existing structure (sample C, D), the value of preferred above-mentioned relative area intensity is more than 0.6 and below 1.5.If relative area intensity is more than 1.5, estimate that then the carrier concentration of protective layer excessively increases, insulation resistance descends, and the confining force of wall electric charge descends, and this is not preferred.

Have again, because how many wavelength has dispersiveness, so in fact more than supposition 720nm and the luminescence peak intensity that wave band produced below the 770nm be first intensity, when the 300nm luminescence peak intensity that wave band produced above and that 450nm is following was second intensity, above-mentioned first intensity of preferred above-mentioned luminescence peak area was more than 0.6 and below 1.5 with respect to the relative area intensity of above-mentioned second intensity.

Then, the peak value of the discharge ionization voltage of the protective layer of cathodoluminescence mensuration shown in Figure 8 and the about 510nm of emission wavelength is with respect to the relation of the relative area intensity of the peak strength of the about 410nm of emission wavelength.Specifically, the difference of sample is as follows successively from the little value of the discharge ionization voltage of transverse axis.

The H of the Ge+1200 quality ppm of sample E:(MgO+50 quality ppm)

Sample F: (Ge of MgO+50 quality ppm)

The H of sample G:(MgO+1200 quality ppm)

Sample H:(only is MgO, existing structure)

Have, condition determination is as follows again.

Beam voltage: 5kV

Heater current density: 6.3 * 10 ⁵(A/cm ²)

Herein, why different current density is with the condition determination shown in Fig. 6,7, are that the beam spot diameter, of electron beam has very big-difference because measure with other device in Fig. 8.

From this Fig. 8 as can be known, if the value of above-mentioned relative area intensity is more than 0.9, then compare with existing structure (sample D), discharge ionization voltage has reduced.Have again, because how many wavelength has dispersiveness, so when in fact being second intensity more than supposition 450nm and less than the luminescence peak intensity that wave band produced of 600nm, preferred above-mentioned second intensity is more than 0.9 with respect to the relative area intensity of above-mentioned the 3rd intensity (300nm above and less than the luminescence peak intensity that wave band produced of 450nm).

And then as can be known, for the protective layer among the present invention, if above-mentioned relative area intensity is more than 0.9, then no matter be combination with Ge+H as additive, still only with the structure of Ge, all can receive and above-mentioned same effect as additive.

Specifically, can be decided to be with respect to more than the 10 quality ppm and the Ge below the 300 quality ppm and the protective layer that H is distributed to form among the MgO or only make more than the 10 quality ppm and be distributed in the protective layer that forms among the MgO any less than the Ge of 300 quality ppm.Add the embodiment of the structure among the MgO to as such Ge, in the embodiment 2 of Fig. 5, concrete data have been shown an amount of.

Then, specify H required among the present invention and the addition of Si.

＜about H and Si addition〉to MgO

Then, the result that the present inventor studies the composition that can effectively obtain the protective layer of effect of the present invention is shown.

At this, available secondary ion mass spectrometry with halogen labeling (SIMS:Secondary Ion MassSpectrometry) is studied the content of Si in the protective layer 15.

On the other hand, available H forward scattering method (HFS:Hydrogen Forward Scatting) is studied the content of H in the above-mentioned protective layer 15.

As mentioned above, as can be known, all be contained in the protective layer of the structure in the MgO at Si and H after changing the addition of H and Si and having investigated discharge dispersity, the addition scope of this Si is preferably more than the 20 quality ppm and below the 10000 quality ppm.

And then, if Si content is the scope that 50 quality ppm are above and 1000 quality ppm are following as can be known, the effect of the discharge dispersity that then is inhibited especially easily.That is, in the embodiment of Fig. 4 f, g, h, the Si addition is respectively 100 quality ppm, 500 quality ppm, 1000 quality ppm as can be known, but discharge dispersity is little.Think that thus for the addition of Si, if be the scope that 50 quality ppm are above and 1000 quality ppm are following, then discharge dispersity is little.

Have, be less than at Si content under the situation of 20 quality ppm, discharge lag inhibition effect becomes very little as can be known.Otherwise, if Si content greater than 5000 quality ppm, then discharge dispersity becomes greatly, and also can the crystallinity of protective layer be made a very bad impression as can be known from the result of X-ray diffraction mensuration etc.

On the other hand, carried out learning after the investigation that in the structure of above-mentioned protective layer, the addition scope as the hydrogen that should add with silicon is preferably the scope that 300 quality ppm are above and 10000 quality ppm are following based on HFS.

Have, be less than at Si content under the situation of 20 quality ppm, discharge lag inhibition effect becomes very little as can be known.Otherwise, if Si content greater than 5000 quality ppm, then discharge dispersity becomes greatly, and also can the crystallinity of protective layer be made a very bad impression as can be known from the result of X-ray diffraction mensuration etc.

And then as can be known, if H content is the scope that 1000 quality ppm are above and 2000 quality ppm are following, the effect of the generation of the discharge lag that then is inhibited especially easily is preferred.

In addition, at this moment, if H content is less than 300 quality ppm, then because the additive effect of H becomes very little, so be not preferred.Otherwise, if the addition of H greater than 10000 quality ppm, then because the carrier concentration of protective layer excessively increases, and insulation resistance reduces, the confining force of wall electric charge reduces, so this also is not preferred.

And then protective layer of the present invention takes to add the structure of an amount of H in MgO shown in embodiment d, the e of Fig. 4, also can obtain and the same effect of protective layer that contains the above-mentioned Si and the H of ormal weight.

From above data as can be known, as the amount of adding the H atom among the MgO with Si to, preferably be in the scope that 300 quality ppm are above and 10000 quality ppm are following.

Then, specify H required among the present invention and Ge addition to protective layer.

＜about H and Ge addition〉to MgO

Then, the result that the present inventor studies the composition that can effectively obtain the protective layer of effect of the present invention is shown.

At this, available secondary ion mass spectrometry with halogen labeling (SIMS:Secondary Ion MassSpectrometry) is studied the content of Ge in the protective layer 15.

On the other hand, available H forward scattering method (HFS:Hydrogen Forward Scatting) is studied the content of H in the above-mentioned protective layer 15.

At first, carrying out learning after the investigation that all be contained in the protective layer of the structure in the MgO at Ge and H, the addition scope of this Ge is preferably more than the 10 quality ppm and less than 500 quality ppm based on SIMS.

And then as can be known, if Ge content is the scope that 20 quality ppm are above and 100 quality ppm are following, then image displaying quality is outstanding especially.

Have, be less than at Ge content under the situation of 10 quality ppm, the effect of keeping wall electric charge confining force as can be known becomes very little.Otherwise, if Ge content greater than 500 quality ppm, then discharge lag becomes greatly, and also can the crystallinity of protective layer be made a very bad impression as can be known from the result of X-ray diffraction mensuration etc.

On the other hand, carried out learning after the investigation, in the structure of above-mentioned protective layer, as the addition scope of the H that should add with Ge, the scope that preferred 300 quality ppm are above and 10000 quality ppm are following based on HFS.

And then as can be known, if H content is the scope that 1000 quality ppm are above and 2000 quality ppm are following, the effect of the generation of the discharge lag that then is inhibited especially easily is preferred.

In addition, at this moment, if H content is less than 300 quality ppm, then because the additive effect of H becomes very little, so not preferred.Otherwise, if the addition of H greater than 10000 quality ppm, then because the carrier concentration of protective layer excessively increases, and insulation resistance reduces, the confining force of wall electric charge reduces, so this also is not preferred.

Have again; as embodiment hereto; addressed to MgO and added H and except that H, also add Si or protective layer that Ge forms; but in the present invention; also can take only in MgO, to add H in addition, and be set at more than the 300 quality ppm addition of this H atom and the structure of the scope below the 10000 quality ppm.

And then, from other experimental data as can be known, in the structure of the protective layer that only in MgO, adds H, preferably the addition of H atom is set at more than the 300 quality ppm and less than the scope of 1500 quality ppm.

The manufacture method of＜PDP 〉

At this, with regard to the manufacture method of the PDP1 of execution mode 1, the formation method ground that comprises protective layer of the present invention illustrates the one example.

(making of front panel)

On the face of the front panel glass that constitutes by soda-lime glass of the about 2.6mm of thickness, make show electrode.At this, the example that forms show electrode with print process is shown, and formation such as also available in addition mold coating process, scraper coating process.

At first, the figure with regulation applies ITO (transparency electrode) material on the glass sheet in front.Make ITO material drying.On the other hand, make the light sensitive paste that photoresist (photolysis resin) and metal (Ag) powder and organic vehicle are mixed.With its overlapping being coated on the above-mentioned transparent electrode material, apparatus has the mask of the figure of show electrode to be formed to cover.Then, expose from this mask, through developing procedure, sintering under the sintering temperature about 590～600 ℃.Thus, on transparency electrode, form bus.Adopt this photomask method, and be that the silk screen print method on boundary is compared with the live width of 100 μ m in the past, can make bus taper to live width about 30 μ m.Have again, as the metal material of this bus, available in addition Pt, Au, Ag, Al, Ni, Cr and tin oxide, indium oxide etc.

In addition, above-mentioned electrode also can form carrying out etching processing with vapour deposition method, sputtering method etc. after with the electrode material film forming except that said method.

Then, on the show electrode after form coating to have mixed softening point be the dielectric glass powder of 550 ℃～600 ℃ lead oxide system or bismuth oxide system and the paste of the organic binder bond that is made of butyl ether acetic acid esters etc.Then, about 550 ℃～650 ℃, carry out sintering, form dielectric layer.

Then, on the surface of dielectric layer, form the protective layer of specific thickness with EB (electron beam) vapour deposition method.Like this, available electron bundle vapour deposition method obtains containing among the present invention the protective layer 15 of an amount of Si or Ge.

The vapor deposition source of using as film forming, for example or use graininess or pulverous Siization thing or Geization thing are mixed into product among the granular MgO, perhaps use sintered body with pulverous MgO and pulverous Siization thing or the mixed product of Geization thing or its mixture.The concentration of above-mentioned Siization thing and Geization thing is decided to be 20～10000 quality ppm and 5～700 quality ppm respectively.Then, in oxygen atmosphere, be heating source with Pierre Si (Pierce) formula electron beam gun, heat above-mentioned vapor deposition source to form desirable film.At this, the electron beam current amount during owing to film forming, partial pressure of oxygen amount, substrate temperature etc. do not have big influence to the composition of the protective layer after the film forming, so can set arbitrarily.

In case after the film film forming of MgO, then this film is carried out plasma treatment containing under the atmosphere of H.For example, at the indoor heater of the doping treatment of H atom substrate being heated to 100～300 ℃, with the doping treatment indoor exhaust, is 1 * 10 until vacuum degree ^-4～7 * 10 ^-4Till the Pa.Thereafter, Yi Bian regulate pressure, Yi Bian import Ar gas, making vacuum degree is 6 * 10 ^-1Pa.Then, on one side with 1 * 10 ^-5～3 * 10 ^-5m ³/ minute flow import H ₂Gas, with high frequency electric source apply the high frequency of 13.56MHz on one side, in the indoor generation discharge of the doping treatment of H atom.

Then,, make it to produce plasma, be exposed among the H of excitation state about 10 minutes by the protective layer 15 that makes film forming on substrate, carry out the doping treatment of the H atom of protective layer 15 by this discharge excitation H atom.

Have again,, be not limited to the electron beam evaporation plating method, also available sputtering method, ion plating etc. as above-mentioned film build method.

Made front panel with above technology.

(making of rear board)

On the surface of the rear board glass that constitutes by soda-lime glass of the about 2.6mm of thickness, will be that the conductive material of main component is applied as strip at certain intervals with Ag with silk screen print method, form the addressing electrode of the about 5 μ m of thickness.At this, be for example the NTSC standard or the VGA standard of 40 inches grades in order to make PDP1 to be made, set 2 adjacent addressing electrodes be spaced apart about 0.4mm or under it.

Then, the lead of about 20～30 μ m of applied thickness is the glass paste and carries out sintering on whole of the rear board glass that has formed addressing electrode, forms dielectric film.

Then, adopting the lead identical with dielectric film is glass material, is forming the spaced walls that highly is about 60～100 μ m on the dielectric film between every adjacent addressing electrode.This spaced walls for example repeatedly silk screen printing contain the paste of above-mentioned glass material, carry out sintering thereafter and form.Have again, in the present invention, if be to contain the Si composition in the glass material, then owing to improved the effect that the impedance that suppresses protective layer is risen, so be preferred at the lead that constitutes spaced walls.This Si composition can be included in the chemical composition of glass, also can be added in the glass material.In addition, the impurity that vapour pressure is high (N, H, Cl, F etc.) additive also can add with the gas shape in gas phase when the MgO film forming in right amount.

After forming spaced walls, on the surface of the dielectric film that exposes between the wall of spaced walls and spaced walls, coating contains any the fluorescent ink in redness (R) fluorophor, green (G) fluorophor, blueness (B) fluorophor, makes it dry and sintering, forms luminescent coating respectively.

The chemical composition of RGB fluorescence of all kinds is for example as follows.

Red-emitting phosphors: Y ₂O ₃: Eu ³⁺

Green-emitting phosphor: Zn ₂SiO ₄: Mn

Blue emitting phophor: BaMgAl ₁₀O ₁₇: Eu ²⁺

It is the material of 2.0 μ m that each fluorescent material can use average grain diameter.With in the fluorescent material input dish, and drop into ethyl cellulose with the ratio of 50 quality %, drop into solvent (α～terpineol), mix to make 15 * 10 with puddle mixer with 49 quality % with 1.0 quality % ^-3The fluorescent ink of Pas.Then, be that the nozzle of 60 μ m is sprayed on fluorescent ink between the spaced walls 20 from diameter with pump.At this moment, panel is moved, into strips along the long side direction of spaced walls 20 with fluorescent ink applicating.500 ℃ sintering 10 minute, form luminescent coating 21～23 thereafter.

Finished rear board with above technology.

Have, though supposition front panel glass and rear board glass are made of soda-lime glass, this only exemplifies out as one of material, also available material in addition again.

(PDP finishes)

Front panel and rear board with glass for sealing applying made.Thereafter, with the exhaust gas inside of discharge space to high vacuum (1.0 * 10 ^-4Pa) about, (be that 66.5kPa～101kPa) inclosure Ne-Xe is or discharge gass such as He-Ne-Xe system, Xe-Ar system with the pressure of stipulating herein.

Finished PDP1 with above technology.

Then, about the manufacture method of PDP, execution mode to be described with above-mentioned different protective layer film build method example.

＜other film forming example 1 〉

In this film forming example 1, adopt at first that to address with MgO be main component contains the film of the Si of regulation or Ge in MgO method in above-mentioned execution mode 1.

Then,, adopt the generating unit of H ion as the method for this film being carried out the doping treatment of H atom, thus with the H ion exposure to the film surface.

As imposing a condition of this moment, for example substrate is heated to 100～300 ℃ in that the doping treatment of H atom is indoor, and, is 1 * 10 until vacuum degree with the doping treatment indoor exhaust with heater ^-4～7 * 10 ^-4Till the Pa.

Thereafter, from the ion gun that links with the H gas cylinder with the H ion exposure on the protective layer 15 of film forming on the substrate, thus protective layer 15 is carried out the doping treatment of H atom.The flow of setting H is 1 * 10 ^-5～3 * 10 ^-5m ³/ minute scope.

＜other film forming example 2 〉

In this film forming example 2, at first form the film that constitutes by MgO with the method described in the above-mentioned execution mode 1.It is indoor then this film to be placed on doping treatment, carries out plasma treatment under the atmosphere of H containing, and the vapor deposition source of having mixed Siization thing or Geization thing with the electron beam gun heating.Thus, can form the protective layer that contains H and Si or Ge.

＜other film forming example 3 〉

In this film forming example 3, form the film that constitutes by MgO with the method described in the above-mentioned execution mode 1.It is indoor then this film to be placed on doping treatment, and on one side from the ion gun that links with the H container with the H ion exposure to substrate, on one side mixed Siization thing or Geization thing with the electron beam gun heating vapor deposition source.Adopt this method, also can form the protective layer that contains H and Si.

＜other item 〉

Film build method as the protective layer in the gas discharge display panel of the present invention is not limited to the respective embodiments described above, also can utilize other method, for example sputtering method, ion plating etc.

＜execution mode 2 〉

Fig. 9 is the cross-sectional conceptual figure of structure of the front panel periphery of the PDP of expression in the execution mode 2.The basic structure of this PDP is identical with above-mentioned execution mode 1, and the structure of protective layer 15 is then different.In present embodiment 2; it is characterized in that; as protective layer 15; structure with the 2nd diaphragm 152 of film formed the 1st diaphragm 151 and stacked formation thereon; in the film of the 1st diaphragm 151; compare with intrinsic the 2nd diaphragm 152, contain the impurity (H, Cl, F etc. form dangling bonds and have the impurity of the ability that makes the MgO activation in MgO) of volume.At this, the thickness of the 1st diaphragm 151 can be decided to be about 600nm, and the thickness of the 2nd diaphragm 152 can be decided to be about 30nm.

Like this; compared with the past, the 1st diaphragm 151 that is activated what be adsorbed on the gas that comprises unwanted composition such as carbon of sneaking in the manufacturing process easily, makes the protective layer of secondary electron yield γ than existing value raising and become; consequently, the raising of expectability energy.That is, the 1st diaphragm 151 is owing to the formation that is activated as the MgO film that mixes impurity such as a lot of H, so compare with the protective layer that is made of MgO in the past, secondary efficient is further enhanced, and further reduces discharge ionization voltage.

According to above-mentioned; as protective layer 15; possess the 1st diaphragm 151 and be layered in its whole lip-deep the 2nd diaphragm 152; and the 1st diaphragm 151 comprise than the 2nd diaphragm 152 more impurity; by formation like this, reduced comprising not the absorption in the manufacturing process in atmosphere, and reduced discharge ionization voltage significantly for the gas of the required composition of protective layer 15; widen driving margin, thereby can obtain not having black noise PDP that take place, that improved display quality and reliability.

In fact; experimental result according to the embodiment that has adopted present embodiment 2; the protective layer of the secondary efficient that the protective layer 15 of this PDP is had and 1 layer of structure in the past is further enhanced with comparing as the protective layer of the above-mentioned patent documentation 1 of 2 layers of structure; secondary electron yield γ has about 0.3 value; discharge ionization voltage can decline to a great extent to about 120V than the 180V of existing value, can confirm that driving margin is widened.

In addition, the PDP with above-mentioned protective layer also clearly is, the dispersiveness of the discharge ionization voltage of discharge cell has also reduced, and the display defect of black noise sharply reduces.

The below affirmation experiment of other of explanation present embodiment 2.Figure 12 is the result that structure (for protective layer 1) that impurity was controlled and imported to investigation to the MgO film of above-mentioned protective layer is placed on the XPS data that the adsorbance of the moisture in the atmosphere draws.In this Figure 12, adopt the high MgO film (for protective layer 2) of purity that does not import impurity, these protective layers to be placed in the atmosphere for relatively, perhaps under 500 ℃, in atmosphere, carry out heat treatment in 2 hours.

From this Figure 12 as can be known, imported the water adsorption amount of protective layer 1 of impurity than the protective layer more than 2 that does not import impurity.

Think thus, fully be reflected in the aspect of performance of PDP, utilize the embodiment of the problem of following expression gas absorption shown here, can more effectively and stably realize aforesaid invention for making effect among the present invention.

(about manufacture method)

Manufacturing process's example of the protective layer 15 in the present embodiment 2 now is described.

Taking it by and large; after on adopting sputtering method (method in the present embodiment 1) and electron beam evaporation plating method or the whole surface of CVD method, forming the 1st diaphragm 151 that constitutes by MgO at dielectric layer 14; with stacked formation the 2nd diaphragm 152 of the such metal oxide of MgO of high purity, make it to cover the whole surface of the 1st diaphragm 151.

(a)

At first, configuration show electrode 12,13 is gone up on glass sheet 11 surfaces in front, and forms dielectric layer 14 with its covering.

(b)

By use Ar ion from sputter equipment to MgO target sputter plasma state, on the surface of dielectric layer 14 form 1st diaphragm 151 of thickness about 600nm thereafter.

In this manufacturing process (b), the limit imports H in above-mentioned Ar gas ₂Gas limit film forming is mixed H as impurity with this to the 1st diaphragm 151.Thus, the MgO that becomes the 1st diaphragm 151 forms so-called dangling bonds and is activated, and secondary electron yield γ is higher than protective layer zone (or protective layer of existing structure) in addition.

At this, so-called " dangling bonds ", be meant unsaturated bond that the atom group of surrounding film near surface or inner certain lattice defect (being oxygen defect herein) is had or associative key not, be easy to capture foreign gas atoms such as carbon in attract electrons and the manufacturing process at this.Have, the content of the H impurity in preferred the 1st diaphragm 151 is 1 * 10 again ^18-23/ cm ³Scope, very few as the doping impurity amount, then secondary electron yield γ is the value of existing level, as too much, then film resistance is low excessively, is difficult to keep writing the wall electric charge of data, therefore must be noted that.

(c)

Then, in sputter equipment,, form the 2nd diaphragm 152 that constitutes by intrinsic MgO film of the about 30nm of thickness with Ar gas sputter MgO of high purity target.According to this method; formed the 2nd diaphragm 152 can be used as minimizing comprises the gas absorption of unwanted composition in technology film; by also covering the absorption impurity such as carbon be adsorbed on the foreign gas in above-mentioned formed the 1st diaphragm 151, thereby the burst size of the foreign gas that can make in the panel gap to be discharged reduces significantly.

Specifically; in manufacturing process; the burst size of the gas of unwanted composition is reduced to about about 1/5 than existing method when comprising deairing step; comprise in the atmosphere technology generated does not reduce significantly for the absorption of the gas of the composition of protective layer needs, the evacuation time in the time of can making panel sealing shortens to about 1/2.

In addition; according to above-mentioned; by form the 2nd diaphragm on the whole surface of the 1st diaphragm, the evacuation time in the time of also can expecting to obtain sealing deairing step that a kind of PDP of shortening makes is to reduce manufacturing cost and to reduce the manufacture method of driving voltage with the PDP that reduces the drive circuit cost.

Have again, in above-mentioned, illustrated that the impurity of sneaking in the 1st diaphragm is H, but equally also can be Cl, the F etc. that can form dangling bonds, the perhaps impurity of their combination.Can on one side these gases be sneaked in the Ar gas, on one side film forming.

In addition, in above-mentioned, the thickness with the 1st diaphragm is decided to be about 600nm, the thickness of the 2nd diaphragm is decided to be about 30nm is described, but the thickness of the 1st diaphragm and the 2nd diaphragm also can be adjusted respectively in the scope of 10nm～1 μ m.Preferably after the PDP sealing is finished, in the starting stage of discharge, compare with the 1st diaphragm, preferred the 2nd diaphragm is the film of 10nm～100nm, so that come sputter to remove the 2nd diaphragm by discharge.At the 2nd diaphragm is under the situation of the film about 10nm, and this film can form on a face in the regulation zone, and if exceed the scope of this thickness, then tend to become the one-tenth membrane stage of island.

＜execution mode 3 and 4 〉

Figure 10 is the profile (Figure 10 (a)) and the plane concept map (Figure 10 (b)) of the schematic front panel peripheral structure of the discharge cell in the expression execution mode 3.

As shown in the drawing, execution mode 3 is characterised in that, all is the 2nd diaphragm 153 of the protective layer 15 that forms of base material with BaO, forms strip on the surface of the 1st diaphragm 151.The area occupation ratio that the 2nd diaphragm 153 of this strip is set to respect to the width W of show electrode 12,13 is about 30%.

On the other hand, Figure 11 is the profile (Figure 11 (a)) and the plane concept map (Figure 11 (b)) of the schematic front panel peripheral structure of the discharge cell in the expression execution mode 4.Present embodiment 4 is characterised in that, forms the 1st diaphragm 151 that is made of BaO on the surface of dielectric layer 14, and stacks gradually the 2nd diaphragm 154, is exposed to discharge space so that the 1st diaphragm 151 is paliform.The area occupation ratio that the 2nd diaphragm 154 of this paliform is set to respect to the width W of show electrode 12,13 is about 80%.

The thickness of the 1st diaphragm can be set in the scope of 10nm～1 μ m, for example can be set at about 600nm.On the other hand, can set the 2nd diaphragm is that thickness is more than the 10nm and the film of the following thickness of 100nm.

At this, as impurity, Si is 1 * 10 ^18～23/ cm ³Concentration range in the 1st diaphragm 151 is mixed.This dopant material except that Si, also can adopt among H, Cl, F, Ge, the Cr more than a kind.

Have, the 1st diaphragm and the 2nd diaphragm can be that base material is made with at least a kind the metal oxide materials that comprises among MgO, CaO, BaO, SrO, MgNO and the ZnO again.

According to the execution mode 3 and 4 of structure like this, during driving in having highly purified the 2nd diaphragm 153,154 electronics be excited near the conduction band and be activated, brought into play high secondary efficient.And, utilize the 1st diaphragm 151 mix above-mentioned Si etc., can reduce sneaking into of unwanted gas componant in this protective layer, realize that this gas componant is discharged into the minimizing of the amount in the discharge space.Thus, as whole protecting layer 15, brought into play high function.

At this; in the experimental result of the embodiment that has used structure with execution mode 3; except that receive with above-mentioned execution mode 1 and 2 roughly the same effects, the secondary electron yield γ of the protective layer 15 of present embodiment 3 was further enhanced than in the past as can be known, had about 0.32 value.Thus, discharge ionization voltage can decline to a great extent to about 115V than the 180V of existing value, has confirmed that driving margin is widened.

In addition, in the determination experiment of the embodiment that has used execution mode 4, also confirmed the excellent effect roughly the same with the embodiment of execution mode 3.

(about manufacture method)

(a)

After having formed dielectric layer 14, be not exposed in the atmosphere, and with BaO film film forming in sputter equipment.Like this, make BaO film film forming, can prevent from this film, to sneak into CO by the blocking-up atmosphere ₂, H ₂Unwanted gas such as O.

At this, in sputter equipment, sputter MgO of high purity target in Ar gas forms intrinsic BaO film through metal mask (omitting diagram).

Then, to the Ar ion of the BaO target sputter plasma state of having sneaked into Si.Thus, the 1st diaphragm 151 thickness with about 600nm on the surface of dielectric layer 14 is formed.

At this, the content of wishing Si impurity is 1 * 10 ^18～23/ cm ³Scope.Doping as this impurity is very few, then secondary efficient be same degree in the past, as too much, then film resistance is low excessively, is difficult to keep conduct to write the wall electric charge of data.By this adjusting, more in the past than the unwanted foreign gases such as carbon in formed the 1st diaphragm of the BaO film that more the was activated 151 easier absorption manufacturing process, but compare with MgO, can obtain the protective layer that secondary efficient is further improved.

(b)

Then, on the surface of above-mentioned the 1st diaphragm 151, figure in accordance with regulations forms the 2nd diaphragm 153,154.For example, the metal mask (omitting diagram) that passes through the composition of stipulating in sputter equipment, carries out sputter to highly purified MgO target in Ar gas.

Then, form the 2nd diaphragm 153,154 of intrinsic MgO film with the thickness of about 50nm.At this, the 2nd diaphragm 153,154 is according to the ratio film forming of this occupied under show electrode 12 (width W) area, with the area occupation ratio that obtains stipulating.

Have, about the 2nd diaphragm 154, but also irregular terrain profiles becomes island again, and its thickness is the scope that 10nm is above and 30nm is following.

In addition; according to above-mentioned; as protective layer; the 1st diaphragm and the 2nd protective film are stacked film forming formation; at least a portion surface of the 1st diaphragm under the show electrode is exposed, can obtain the evacuation time of a kind of shortening when the sealing deairing step that PDP makes thus to reduce manufacturing cost and to reduce the manufacture method of driving voltage with the PDP of reduction drive circuit cost.

In addition, though protective layer used sputtering method forms in above-mentioned, also available electron bundle vapour deposition method, CVD method in addition, film forming perhaps combines these two kinds of methods.At least preferred the 1st diaphragm sputtering film-forming can make the secondary efficient of protective layer and anti-sputter be further enhanced.

Industrial utilizability

Gas discharge display panel of the present invention can be used for large-scale tv and high definition television or large-scale aobvious In the image equipment industry such as showing device, the industry of publicity equipment, industrial equipment and other industrial circle.

Claims (14)

1. A gas discharge display panel, comprising a panel whose surface is sequentially laminated with a dielectric layer and a protective layer, wherein the protective layer has a first protective film formed on the surface of the dielectric layer and a surface of the first protective film. The second protective film is stacked on at least a part of the region, and the first protective film has a structure containing more impurities than the second protective film. 2. The gas discharge display panel according to claim 1, wherein the second protective film is laminated so as to cover the entire surface of the first protective film. 3. The gas discharge display panel according to claim 1, wherein the second protective film is stacked so as to expose at least a part of the surface of the first protective film under the display electrodes. 4. The gas discharge display panel according to claim 3, wherein, with respect to the second protective film, the proportion of the second protective film occupying the area of the first protective film under the display electrodes is not less than 10% and 90%. % below the area ratio. 5. The gas discharge display panel according to claim 1, wherein the film thickness of the second protective film is not less than 10 nm and not more than 1 μm. 6. The gas discharge display panel according to claim 1, wherein the film thickness of the second protective film is not less than 10 nm and not more than 100 nm. 7. The gas discharge display panel according to claim 1, wherein the impurity mixed into the first protective film is an impurity containing at least one of H, Cl, F, Si, Ge, and Cr. 8. The gas discharge display panel according to claim 1, wherein a content of the impurity in the first protective film is in a range of not less than 10 ppm and not more than 10000 ppm. 9. The gas discharge display panel according to claim 1, wherein the first protective film and the second protective film are made of at least one metal oxide material selected from MgO, CaO, BaO, SrO, MgNO and ZnO way of film formation. 10. The gas discharge display panel according to claim 9, wherein any one of the first protective film and the second protective film is formed to contain MgO. 11. The gas discharge display panel according to claim 9, wherein the first protective film is formed of BaO, and the second protective film is formed of MgO. 12. The gas discharge display panel according to claim 1, wherein the second protective film is formed in the shape of islands or stripes on the surface of the first protective film. 13. A method for manufacturing a gas discharge display panel, comprising a step of forming display electrodes formed in pairs on a first substrate, a step of forming a dielectric layer formed to cover the display electrodes, and forming a layer formed on the surface of the dielectric layer. A step of forming a protective layer of a protective layer, and a step of arranging a second substrate facing the first substrate with a gap therebetween, wherein the step of forming the protective layer is formed by forming a first protective film containing many impurities on the surface of the dielectric layer A protective layer is formed by forming a film without being exposed to the atmosphere, and laminating a second protective film on at least a part of the surface of the first protective film without being exposed to the atmosphere. 14. The method of manufacturing a gas discharge display panel according to claim 13, wherein in the protective layer forming step, at least one of the first protective film and the second protective film is formed by a sputtering method.

Images