JP2012207310A - Vapor deposition method of metal oxide film, and method for manufacturing plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a metal oxide film by vapor-depositing a metal oxide that is an evaporation material, particularly for forming a protective film for a plasma display panel (hereafter referred to as PDP), which improves the productivity and panel characteristics by increasing a film-forming rate of an MgO film oriented in <111> direction as the protective film.SOLUTION: The method for forming a metal oxide film by vapor-depositing a metal oxide, that is an evaporation material, includes: employing an electron gun as a means for heating the evaporation material; narrowing the electron beam emitted from the electron gun; and controlling the oscillation waveform of the electron beam, based on the diameter of the electron beam and according to the surface area irradiated with the electron beam to the evaporation material. This method increases the film-forming rate of the MgO film which is the protective film for the plasma display, which includes a front substrate comprising a scanning electrode, a sustaining electrode, a dielectric layer and the protective film, and a back substrate comprising an address electrode, a barrier rib, and a fluorescent body, and also provides the adequate panel characteristics.

Description

  The present invention relates to a method for depositing a metal oxide film using a metal oxide as an evaporation material, and more particularly to formation of a protective film for a plasma display panel (hereinafter referred to as PDP).

  The AC surface discharge type PDP, which is the mainstream of the current PDP, is composed of a front substrate composed of scan electrodes, sustain electrodes, dielectric layers and protective films, and a rear substrate composed of address electrodes, barrier ribs and phosphors (FIG. 5). reference).

  As shown in FIG. 5, in the AC surface discharge type PDP 81, two glass substrates are frit-sealed through a narrow gap filled with a discharge gas. On the rear glass substrate 90, address electrodes 89 are arranged in the column direction, and a dielectric layer 87 is formed thereon. The dielectric layer 87 serves to protect the address electrodes 89 and to improve luminance as a white inversion layer. The barrier rib 88 has a height of about 100 to 150 μm, and red, blue, and green phosphors (91R, 91B, and 91G) are sequentially applied to the inner wall of the groove formed by the barrier rib 88.

  The front substrate on the display side is provided with a surface discharge electrode composed of a transparent electrode such as ITO and a bus electrode. The image discharge electrodes are arranged in pairs with a discharge gap of about 50 to 100 μm. These discharge electrodes are covered with a dielectric layer having a thickness of about 20 to 30 μm. A protective film made of magnesium oxide (MgO) is formed on the top.

  One cell serving as a display unit of each color has a surface discharge electrode (scanning electrode 83 and sustaining electrode 84) covered with dielectric layers 85 and 87 and an address electrode 89 with respect to a discharge space in which a phosphor is applied around. It consists of three electrodes consisting of A scan pulse having a negative potential is sequentially applied to the scan electrode 83, and a data pulse having a positive potential is applied to the address electrode in accordance with display data in synchronization therewith, thereby selectively generating an address discharge. Subsequently, an AC sustain discharge pulse is applied between the sustain electrode and the scan electrode, and the written cell is subjected to a sustain discharge, thereby causing light emission display.

  As described above, MgO is mainly used for the protective film. Further, MgO is required to have a large secondary electron emission coefficient in addition to a function as a protective film.

  When paying attention to this secondary electron emission, there is a method of obtaining a <111> oriented MgO film (see Patent Document 1). This is a method using a vacuum vapor deposition method performed in an oxygen atmosphere or an ion assist vapor deposition method in which an ion beam is irradiated on the vapor deposition surface.

  However, in order to obtain a highly accurate MgO film, an evaporation method using an electron beam having better controllability than an ion beam is desirable. Here, in order to obtain a <111> -oriented MgO film by an evaporation method using an electron beam, it is deposited at a substrate temperature of 230 ° C. or higher, or 1.5 to 3 seconds / second. It was necessary to form at a deposition rate (see Patent Document 2).

  This method uses an electron beam to base a <111> oriented magnesium oxide film at a substrate temperature of 230 ° C. or higher and 350 ° C. or lower or a deposition rate of 1.5 Å / second or higher and 3 Å / second or lower. Form as. Subsequently, a <111> -oriented protective film can be obtained by electron beam evaporation at a low substrate temperature and a high deposition rate.

  However, since the process for forming the base and the process for forming the protective film are required, two steps are required, and the conditions for both processes are different. It was.

JP-A-5-234519 (page 3, FIG. 3) JP-A-8-287833 (page 3, Table 1)

As the price of PDP decreases and demand increases, the size of the mother glass becomes larger and the throughput of the production apparatus for forming MgO, which is a protective film of the PDP, is becoming shorter.
Accordingly, it is necessary to increase the evaporation rate of MgO, which is a metal oxide. In order to reduce impurity contamination and improve panel characteristics, it is effective to increase the evaporation rate of MgO.

  In the case of vapor deposition using an electron gun, it is necessary to increase the power of the irradiated electron beam in order to increase the deposition rate. However, when a large amount of power is applied to the MgO single crystal or pellet, which is a metal oxide, a splash (a phenomenon in which the MgO single crystal or pellet breaks up finely) occurs, causing a reduction in product yield (FIG. 6). There is also a method of providing a plurality of evaporation sources in the substrate transport direction in order to suppress the splash and increase the deposition rate, but the MgO deposition rate does not increase significantly, so the effect of reducing impurity contamination There are few.

  In addition, the cost increases because a large number of electron guns and power supplies are required. In addition, the time for the substrate to pass over the evaporation source becomes longer, the substrate temperature rises, the temperature difference from the portion passing over the evaporation source increases, the probability of thermal cracking of the substrate increases, and at the same time, the process temperature Control is also difficult (Figure 9).

  In view of the circumstances as described above, an object of the present invention is to provide a metal oxide film deposition method and a plasma display panel manufacturing method capable of suppressing the splash and improving the deposition rate.

  A metal oxide film deposition method according to an embodiment of the present invention includes using an electron gun as a heating means for an evaporation material made of a metal oxide. The electron beam from the electron gun is narrowed, and the oscillation waveform of the electron beam is controlled according to the irradiation area of the electron beam onto the evaporation material based on the diameter.

  A method for manufacturing a plasma display panel according to another aspect of the present invention is a method for manufacturing a plasma display panel having a protective film made of a metal oxide, and uses an electron gun as a heating means for an evaporation material made of a metal oxide. Including that. The electron beam from the electron gun is narrowed, and the oscillation waveform of the electron beam is controlled according to the irradiation area of the electron beam onto the evaporation material based on the diameter.

It is a schematic diagram which shows the structure of the electron gun used by one embodiment of this invention. (A) is a figure which shows the total in-plane distribution of the electron beam irradiation time to the MgO surface by the conventional rocking | fluctuation waveform, (B) is an electron beam continuously irradiated to the MgO surface on the conventional rocking | fluctuation conditions. It is a figure which shows in-plane distribution of time to be performed. (A) is a calculation model used in the embodiment of the present invention, and (B) is a diagram showing an electron beam fluctuation waveform of one embodiment of the present invention. (A) is a figure which shows the total in-plane distribution of the electron beam irradiation time to the MgO surface by the electron beam fluctuation waveform of one Embodiment of this invention, (B) is the electron of one Embodiment of this invention. It is a figure which shows in-plane distribution of the time when an electron beam is continuously irradiated to the MgO surface on beam rocking conditions. It is a schematic diagram which shows the structure of typical PDP. It is a figure which shows the relationship between the film-forming speed | rate and the frequency | count of splash generation. It is a figure which shows an example which installed multiple evaporation points in the conveyance direction. It is a figure which shows the other example which installed multiple evaporation points in the conveyance direction. It is a graph of the temperature rise of the board | substrate which passes on an evaporation source. It is a figure which shows the example of installation of a CCD camera. It is the photograph of the evaporation source monitored with the CCD camera. It is a photograph which shows the change of the beam shape by a different electron beam current. It is a figure which shows an example of the irradiation method of hearth and an electron beam. It is a figure which shows the other example of the irradiation method of hearth and an electron beam. It is a figure which shows the other example of the irradiation method of hearth and an electron beam. It is a graph which shows the relationship between the jumping period and rate of an electron beam. It is a graph of an electron beam irradiation method and a film formation rate. It is a graph of the current density of the electron beam which does not generate | occur | produce a splash. It is a graph which shows the relationship between substrate heating temperature and <111> orientation intensity | strength. It is a graph which shows the relationship between a substrate heating temperature and a refractive index. It is a related figure of the incident angle of the evaporation particle with respect to an evaporation source and a substrate. It is a graph which shows the relationship figure of the incident angle of the evaporation particle | grains with respect to a board | substrate, and a refractive index. It is a graph which shows the incident angle and <111> orientation intensity | strength of the evaporation particle | grains with respect to a board | substrate.

  A metal oxide film deposition method according to an embodiment of the present invention includes using an electron gun as a heating means for an evaporation material made of a metal oxide. The electron beam from the electron gun is narrowed, and the oscillation waveform of the electron beam is controlled according to the irradiation area of the electron beam onto the evaporation material based on the diameter.

The main cause of the occurrence of splash, which is a problem when depositing a metal oxide film, is considered as follows.
(1) A high-density electron beam is irradiated continuously in a short time, and the temperature of MgO becomes too high, causing splash.
(2) Splash is likely to occur due to temperature changes caused by intermittent irradiation of the electron beam.

  Therefore, in the metal oxide film deposition method according to an embodiment of the present invention, the electron beam is appropriately narrowed down with respect to the size and shape of the evaporation material, and the oscillation waveform is changed to the diameter of the electron beam, the evaporation material and the material shape. Optimize it together. Thereby, it is possible to suppress the splash and improve the film forming speed.

The irradiation condition of the electron beam for suppressing the splash can be determined as follows.
(1) The density of the irradiated electron beam is optimized by the shape of MgO.
(2) The fluctuation waveform of the electron beam is determined so that the time for continuously irradiating the MgO with the electron beam is uniform with respect to the irradiated portion.
(3) At this time, the oscillation waveform of the electron beam is determined so that the total irradiation time for each irradiation point is uniform.

In summary, the solution is as follows, for example.
(1) Based on the diameter of the electron beam, the oscillation pattern is determined so that the residence time or irradiation energy of the electron beam irradiated on the MgO surface is uniform.
(2) At least on all MgO surfaces irradiated with the electron beam, the difference between the longest time and the shortest time of the electron beam residence time, or the difference between the maximum value and the minimum value of the irradiation energy is set within 30%.

  According to one embodiment of the present invention, the dynamic rate without splash was able to achieve 25000 Å · m / min or more. This is a film formation rate of 5 times or more that of the conventional 5000 Å · m / min.

  As a result, for example, in a metal oxide film forming apparatus, which conventionally used six electron guns, two are sufficient, and a significant cost reduction has been realized.

  Further, the present invention can be sufficiently applied to a metal oxide film forming apparatus corresponding to a future large substrate (3500 mm width).

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

  FIG. 1 is a schematic configuration diagram of an electron gun used in an embodiment of the present invention. In the present embodiment, a piercing electron gun will be described as an example, but the type of the electron gun is not limited to this.

  The electron gun 3 is installed in the vapor deposition chamber 2 of the electron beam vapor deposition apparatus. The electron gun 3 includes a filament 36, a cathode 37, Wehnelt 38, and an anode 39. The filament 36 is heated to, for example, about 2500K by energization. A voltage of 600 to 1500 V, for example, is applied between the filament 36 and the cathode 37, and the thermoelectrons generated from the filament 36 bombard the surface of the cathode 37. The cathode 37 is heated to, for example, about 2500 K by electron impact from the filament 36 to generate thermoelectrons from the surface. A voltage of, for example, about 20 kV is applied between the cathode 37 and the anode 39, and the thermoelectrons generated from the surface of the cathode 37 are accelerated in the direction of the anode 39 to form an electron beam F, and the evaporation material is evaporated. The point P is irradiated. Further, the Wehnelt 38 has a function of focusing the thermoelectrons generated from the surface of the cathode 37 in the direction of the anode 39 by a potential gradient formed between the Wehnelt 38 and the anode 39.

  Ions are generated when the thermoelectrons constituting the electron beam F collide with moisture, residual gas, evaporated particles, etc. in the deposition chamber. This ion flows backward toward the cathode 37. Therefore, an ion collector 42 for colliding ions that have passed through the cathode 37 is arranged behind the cathode 37. The ion collector 42 collects the ions that have passed through the cathode 37 and the ion collector components sputtered by the collision of the ions with the ion collector 42.

  The electron gun 3 includes a flow register 43. The flow register 43 has a function of separating a beam generation portion of the electron gun from the atmosphere of the vapor deposition chamber and adjusting a pressure. A focusing coil 40 that focuses the electron beam F and a swing coil 41 that swings the electron beam F are disposed around the flow register 43. The electron gun 3 includes a deflecting device 20 that deflects the electron beam F that has passed through the flow register 43 to the ring hearth 4 side. The ring hearth 4 has a groove 4a for accommodating the evaporating material 11, and is configured to be rotatable. In the present embodiment, MgO is used as the evaporation material 11.

  The oscillation waveform of the electron beam F is controlled by the function generator 48. The output of the function generator 48 is connected to the oscillating coil 41 via the amplifier 47. The function generator 48 uniformly controls the beam irradiation surface of the evaporation material to irradiate the electron beam F by driving and controlling the oscillating coil 41 based on the oscillating waveform obtained in advance by simulation. Here, the beam diameter (diameter) after focusing (aperture) of the electron beam F was set to φ30 mm.

FIG. 2 shows the electron beam irradiation time on the MgO surface by a conventional oscillation waveform.
FIG. 2A confirms the total irradiation time on the MgO surface as an in-plane distribution for every 100 mm ² when the electron beam is irradiated for 0.02 seconds under the rocking conditions described later. FIG. 2B shows the result of confirming the time during which the electron beam is continuously irradiated under the conventional rocking conditions. The electron beam oscillation conditions at this time were as follows: the diameter of the electron beam was 30 mm, the X-Sweep was a simple triangular wave, the frequency was 500 Hz, and the sweep width was ± 60 mm. Y-Sweep is also a simple triangular wave with a frequency of 222 Hz and a sweep width of ± 90 mm.

  A phenomenon is known in which the edge of the surface of the irradiated evaporation material is dug. This is considered that the temperature rises and evaporates while the electron beam is continuously irradiated. The results in FIG. 2 are consistent with this phenomenon.

  In this embodiment, based on the diameter of the electron beam, the fluctuation waveform of the electron beam is controlled in accordance with the irradiation area of the electron beam onto the evaporation material. The oscillation waveform can be controlled in accordance with the shape of the evaporation material based on the diameter of the electron beam. Specifically, the fluctuation pattern of the electron beam can be determined so that the residence time of the electron beam irradiated onto the surface of the evaporation material is uniform. In this case, the uniformity of the stay time of the electron beam irradiated to the evaporation material can be such that the difference between the longest time and the shortest time is within 30% in all the evaporation material surfaces.

  Further, the fluctuation pattern of the electron beam can determine the fluctuation pattern of the electron beam based on the diameter of the electron beam so that the irradiation energy of the electron beam irradiated on the surface of the evaporation material becomes uniform. In this case, the uniformity of the irradiation energy of the electron beam applied to the surface of the evaporating material can be such that the difference between the maximum value and the minimum value is within 30% in all the evaporating material surfaces.

FIG. 3A is a calculation model of an embodiment of the present invention.
As shown in FIG. 3A, the fluctuation of the electron beam was schematically considered. The portion where the electron beam is hit is indicated by a solid circle. The irradiation area of the evaporation material is indicated by a solid square. As shown in FIG. 3A, since the portion where the electron beam hits at the end of the irradiation region is folded back, the time that the electron beam continues to hit at the end becomes long, and the temperature rises instantaneously there.

FIG. 3B is a diagram showing an oscillation waveform and an irradiation time according to the embodiment of the present invention.
The swinging condition of the electron beam at this time is that the electron beam diameter is φ30 mm, the X-Sweep is swept at a frequency of 984 Hz and a width of ± 60 mm, and the end 10 mm is moved 1.8 times faster. On the other hand, Y-Sweep swept at 444 Hz and a width of ± 90 mm, and the end 10 mm moved 1.8 times faster. That is, the electron beam oscillation condition of the present embodiment is such that the scanning speed of the electron beam folding region is set higher than the linear scanning speed in one direction of the electron beam.

4 applies the oscillating waveform according to the present invention, when irradiated with 0.02 seconds electron beam is obtained by calculating the sum of the irradiation time in the MgO surface as a relatively plane distribution per 100 mm ² . The center of the electron beam at 0 seconds was the origin. FIG. 4B shows the time during which the electron beam is continuously irradiated when the fluctuation waveform according to the present invention is applied.

  As shown in FIG. 4A, by applying the oscillation waveform according to the embodiment of the present invention, the total time for which the electron beam is irradiated onto the MgO surface is substantially uniform. In addition, as shown in FIG. 4B, the variation in time during which the electron beam is continuously irradiated is greatly improved.

  FIG. 10 is a schematic side cross-sectional view of the main part of the electron beam evaporation apparatus in the present embodiment. A viewing window 101 is installed on the ceiling of the vapor deposition chamber 2 facing the ring hearth 4. The viewing window 101 is provided with a CCD camera 102 for monitoring the surface temperature of the evaporation material. The output image of the CCD camera 102 is input to the image processing unit 103, and the image processing unit 103 calculates the surface temperature of the evaporation material based on the image of the evaporation material (MgO) on the ring hearth 4 acquired by the CCD camera. A shutter 104 that opens and closes the observation window 101 is installed inside the vapor deposition chamber 2.

  Referring to FIG. 10, the vapor deposition chamber 102 is provided with a transport space 106 for transporting the substrate (carrier) 10. The substrate 10 is transported in the transport space 106 and is formed in the process of passing through the vapor deposition chamber 2. Reference numeral 105 is a control plate for limiting the incident angle of the vapor deposition material with respect to the substrate 10 to a predetermined angle range.

  Actually, the surface temperature of MgO when the electron beam was irradiated under the swing condition according to the present embodiment was monitored by the CCD camera 102. An image photograph at this time is shown in FIG. Due to the difference in the number of rotations of the hearth, the surface temperature of MgO is slightly different from the simulation, so that the monitor result of the CCD camera is reflected directly on the pre-programmed oscillation waveform pattern menu and the oscillation waveform. In this case, the monitor result of the CCD camera may be fed back to the power of the electron gun.

  Further, the incident angle of the electron beam on the MgO surface was set to 40 ° or more. The beam shapes at each electron beam current at this time are shown in FIG. This figure shows the relationship between the output of the electron gun and the irradiation area, and it can be seen that the larger the output, the wider the irradiation area.

  The number of installed electron guns 3 and ring hearths 4 and examples of installation are not particularly limited, and various methods can be employed. For example, FIG. 7 shows an example in which four ring hearts 4 and four electron guns 3 are installed in the vapor deposition chamber 2. Each ring hearth 4 has two evaporation points P1 and P2, and one electron gun 3 irradiates these two evaporation points with an electron beam. FIG. 8 shows an example in which six ring hearts 4 and six electron guns 3 are installed. In this case, the electron gun 3 can be disposed on both sides of the substrate transport direction.

  FIGS. 13 to 15 show examples in which the electron gun 3 and the ring hearth 4 are arranged in a single row perpendicular to the substrate transport direction. FIG. 13 shows an example in which each electron gun 3 irradiates a single evaporation point with an electron beam, and FIGS. 14 and 15 show examples in which each electron gun 3 irradiates two evaporation points with an electron beam. ing. 13 to 15, reference numerals 26 a and 26 b are permanent magnets for deflecting the electron beam.

  FIG. 16 shows the relationship between the electron beam jumping period and the deposition rate (dynamic rate) in the examples of FIGS. The jumping period of the electron beam is preferably 50 to 200 msec as shown in FIG.

  FIG. 17 is a diagram showing the relationship between the electron beam irradiation method and the film formation rate. As a result of using the fluctuation pattern of the electron beam according to the present embodiment, the evaporation rate without splash for MgO is about three times that of the conventional method (550 Å / sec) at the output of the electron gun of 10 kV (20 kW × 0.5 A). ) And 20 kW (20 kV × 1.0 A), about three times as much as the conventional method (1000 kg / sec) was achieved. At this time, the current density of the electron beam without splash is shown in FIG. In the film forming apparatus used in the present embodiment, a dynamic rate of 8000 kg · m / min was obtained at a static rate of 280 kg / sec.

According to this embodiment, when a film thickness of 8000 mm is formed, the amount of heat input to the glass substrate is reduced. As a result, the substrate temperature rise during the film formation (during the process) is reduced, and the film quality control is greatly improved. . The temperature rise when the film was formed at a conventional film formation rate of about 100 Å / sec was about 80 ° C, but the temperature rise was reduced to about 30 ° C when the film was formed at 420 Å / sec.
Converting this to the crystal orientation strength, there was a variation of about 800 cps from 2300 cps to 1500 cps in the past, but the controllability improved to a variation of about 300 cps from 2300 cps to 2000 cps (FIG. 19). That is, the controllability is improved by 2.7 times. FIG. 19 is a graph showing the relationship between the substrate heating temperature and the <111> orientation strength.

  Further, the refractive index has been a fluctuation of about 0.016 from 1.670 to 1.654 in the past, but according to the present embodiment, the fluctuation is about 0.006 from 1.670 to 1.664. Controllability was improved (FIG. 20). FIG. 20 is a graph showing the relationship between the substrate heating temperature and the refractive index.

Moreover, according to this Embodiment, the change of the incident angle decreased and the MgO film became homogeneous.
When trying to obtain a dynamic rate of about 8000 kg · m / min without slush, conventionally, as shown in FIG. 21, a plurality of evaporation points (electron beam irradiation points) are arranged in the transport direction of the glass substrate. Therefore, MgO to the substrate is deposited at incident angles of 30 ° and 60 ° at the start of deposition. At the end of vapor deposition, vapor deposition is performed at incident angles of 60 ° and 30 °. The refractive index (density) and incident angle of the MgO film have a relationship as shown in FIG. 22, and it has been confirmed that the film density (refractive index) varies depending on the incident angle.

  The film density affects the emitted gas characteristics and the etching characteristics, and it is desirable that the incident angle of the evaporated particles be controlled in the MgO film forming process. In addition to the above, the incident angle affects the crystal orientation (FIG. 23). FIG. 23 is a graph showing the relationship between the incident angle and the <111> orientation strength. Therefore, it is desirable that the incident angle during MgO film formation is controlled within a certain range. According to the present invention, even when the dynamic rate is about 8000 kg · m / min or more, the evaporation point in the conveyance direction of the glass substrate may be one point, and the controllability (change) of the incident angle is greatly improved.

Further, according to the present embodiment, impurities in the film can be reduced and the film quality is improved.
In the process chamber during film formation, hydrogen, helium, water, nitrogen, carbon monoxide, carbon dioxide, argon, and the like exist in addition to oxygen as a process gas. In particular, carbon monoxide and carbon dioxide deteriorate the discharge characteristics of the panel. By forming the film at a high rate, the amount of impurities incorporated into the film can be reduced.

  Specifically, the process condition of 8000 Å · m / min (static rate of 280 Å / sec) is twice that of the conventional (4000 Å · m / min, static rate of 140 Å / sec). Therefore, the metal oxide film deposition method of the present embodiment is applied to the formation of the protective film of the front substrate for the plasma display panel shown in FIG. 5, thereby affecting the impurities incorporated into the MgO film, particularly the discharge characteristics. The amount of carbon that gives the effect becomes 1/2 or less, and the panel characteristics are improved. A comparison at one writing speed of the panel characteristics is as follows.

When the carbon content of the impurities in the MgO film becomes 1 / 1.5, the CL (cathode luminescence) intensity becomes about 1.8 times, and the writing speed can be improved. There is a tendency for the CL intensity to decrease as the amount of carbon incorporated into the film increases. Further, there is a tendency that a panel with good response is obtained with an MgO film having a high CL strength.
The incidence frequency of impurities on the glass substrate is determined as follows.

Γ = 2.65 × 10 ²⁴ × P / (M × T) ^1/2
Γ: incidence frequency (pieces / (s · m ² ))
P: Pressure (Pa)
T: Temperature (K)
As a result, the film formation rate was increased, and the amount of impurities was relatively reduced.

In addition, the number of electron guns, electron gun power supplies and hearths can be reduced, and costs can be reduced.
Since the rate without splash has tripled, the required number of electron guns, electron gun power supplies, hearths, etc. has been reduced to 1/2 to 1/3.

  As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to these, A various deformation | transformation is possible based on the technical idea of this invention.

  For example, the present invention can be applied not only to an inline type electron beam vapor deposition apparatus but also to other types of electron beam vapor deposition apparatuses using a piercing electron gun.

  Further, in the electron beam vapor deposition apparatus according to the embodiment of the present invention, the container for storing the evaporation material is a ring hearth, but a crucible may be used.

In the electron beam evaporation apparatus according to the embodiment of the present invention, MgO is used as the evaporation material, but other oxides or metal oxides can be used. For _{example, SiO 2, Al 2 O 3} , SrO, SiO, CaO, ZnO, ZnS, ITO, SnO 2, WO 3, Cr, C, Ca, Sr, Mg can be used.

  DESCRIPTION OF SYMBOLS 2 ... Deposition chamber, 3 ... Pierce type electron gun, 4 ... Ring hearth, 4a ... Groove part, 10 ... Substrate (front substrate), 11 ... MgO (evaporation material), 20 ... Deflection device, 26a ... Permanent magnet, 26b ... Permanent magnet, 36 ... Filament, 37 ... Cathode, 38 ... Wehnelt, 39 ... Anode, 40 ... Focusing coil , 41 ... Oscillating coil, 42 ... Ion collector, 43 ... Flow register, 47 ... Amplifier, 48 ... Function generator, 81 ... Plasma display panel (PDP), 82 ... Front substrate 83 ... Scan electrode 84 ... Sustain electrode 85 ... Dielectric layer 86 ... Protective film (MgO) 87 ... Dielectric layer 88 ... Barrier rib 89... Address electrode, 90. - a rear substrate, 91R, 91G, 91B ··· phosphor, P, P1, P2 ··· evaporation points (electron beam irradiation points)

Claims (5)

Using an electron gun as a heating means for the evaporation material made of metal oxide,
The electron beam from the electron gun is squeezed,
Based on the diameter of the electron beam, the oscillation waveform of the electron beam is controlled according to the irradiation area of the electron beam to the evaporation material,
The control of the oscillation waveform determines the oscillation pattern of the electron beam based on the diameter of the electron beam so that the irradiation energy of the electron beam applied to the surface of the evaporation material is uniform.
The uniformity of the irradiation energy of the electron beam irradiated on the surface of the evaporating material is such that the difference between the maximum value and the minimum value is within 30%, with the maximum value being 100% on all the evaporating material surfaces. Oxide film deposition method. The metal oxide film deposition method according to claim 1,
The control of the oscillation waveform is as follows:
Monitoring the surface temperature of the evaporating material with a CCD camera;
A metal oxide film deposition method for controlling a fluctuation waveform of the electron beam according to a monitoring result. The metal oxide film deposition method according to claim 1,
The control of the oscillation waveform is as follows:
Monitoring the surface temperature of the evaporating material with a CCD camera;
A metal oxide film deposition method for controlling the power of the electron gun according to the monitoring result. The metal oxide film deposition method according to claim 1,
The metal _{oxide, MgO, SiO 2, Al 2} O 3, SrO, SiO, CaO, ZnO, ZnS, ITO, a method of depositing a metal oxide film is any one of _SnO 2, WO _3. A method of manufacturing a plasma display panel having a protective film made of a metal oxide,
Using an electron gun as a heating means for the evaporation material made of metal oxide,
Squeezes electrons from the electron gun,
Based on the diameter of the electron beam, the oscillation waveform of the electron beam is controlled according to the irradiation area of the electron beam to the evaporation material,
The control of the oscillation waveform determines the oscillation pattern of the electron beam based on the diameter of the electron beam so that the irradiation energy of the electron beam applied to the surface of the evaporation material is uniform.
The uniformity of the irradiation energy of the electron beam applied to the surface of the evaporation material is such that the difference between the maximum value and the minimum value is within 30%, with the maximum value being 100% on the surfaces of all the evaporation materials. Display panel manufacturing method.