KR20070018908A - Method for Gettering Oxygen and Water During Vacuum deposition of Sulfide Films - Google Patents

Abstract

The present invention is a method of gettering unwanted atomic species from a vapor atmosphere during vacuum deposition of multi-element thin film phosphor compositions, wherein the method comprises one or more prior to and / or during the deposition of phosphor film compositions in a deposition chamber. Vaporizing the getter species simultaneously. This method improves the brightness and luminescence spectrum of phosphor materials used for full ac ac electroluminescent displays employing thick film dielectric layers with high dielectric constants.

Phosphor composition, deposition, atomic species, gettering, deposition chamber, vaporization, getter species, electroluminescent display, luminance

Description

Method for Gettering Oxygen and Water During Vacuum deposition of Sulfide Films}

The present invention relates to a method for depositing a multi-element thin film composition in which the concentration of oxygen, water and other unwanted atomic species is minimized. More specifically, the present invention is a method of gettering oxygen water and / or other unwanted atomic species from a vapor atmosphere during vacuum deposition of multi-element thin film compositions. In particular, this method is useful for the deposition of phosphors for full color electroluminescent displays employing thick film dielectric layers with high dielectric constants.

Typically, thick film dielectric structures are fabricated on ceramic substrates and provide reduced resistance to dielectric breakdown as well as thin film electroluminescent (TFEL) displays fabricated on glass substrates. When deposited on ceramic substrates, the thick film dielectric structures withstand higher processing temperatures than TFEL devices on glass substrates. The increased tolerance for higher temperatures allows annealing of the phosphor films at higher temperatures, thereby improving the brightness. However, despite the improvement in luminance, it is desired to further increase the luminance efficiency of the device so as to improve the overall energy efficiency and reduce the power consumption.

Applicant has developed a variety of deposition methods for phosphors for use in thick film dielectric electroluminescent devices disclosed, for example, in US Pat. No. 5,432,015 (hereby incorporated herein by reference in its entirety). For example, international patent application PCT CA01 / 01823 (which reflects the entirety thereof) is an electron beam vaporization method for the deposition of tertiary, quaternary or similar phosphor compositions, wherein the components of the compositions are of different sources. Is located on. In particular, the components are thialuminates, thigallates or thioderites of groups IIA and IIB, and the sulfides forming such compounds are located on different sources. Applicant's International Patent Application No. PCT CA01 / 01234, which is hereby incorporated by reference in its entirety, discloses a dual source phospho deposition method using dual source electron beam deposition. The various compounds of the first and second sources have the ratios required to provide the necessary compositions of phosphor. The deposited phosphors are preferably blue emitting europium activated barium thialuminate (BaAl ₂ S ₄ : Eu). Applicant's International Patent Application PCT CA02 / 00688, which is hereby incorporated by reference in its entirety, discloses a single source sputtering method for depositing a multi-element phosphor film of controlled composition. This method uses a source material in the form of a single thick target having a composition different from the desired film composition of the phosphor. The concentration of lighter chemical elements relative to heavier chemical elements in the target composition of the process is higher than desired in the deposition film.

In the deposition of phosphor compositions, it is desired to remove unwanted species from the deposition atmosphere to minimize the risk of such unwanted compounds being incorporated into the deposited phosphor film. Getters are known materials that getter gas reactants in a variety of applications, as disclosed, for example, in US Pat. Nos. 4,062,319, 4,118,542, 5,508,586, 6,514,430, and 6,586,878.

U. S. Patent No. 5,976, 900 discloses a precoat layer provided on the inner surface of a process chamber that acts as a getter for transporting ions. This precoat layer is applied to the surface of the processing chamber prior to wafer processing.

US 6,299,746 discloses a getter system for purifying a gaseous atmosphere in a processing chamber. This getter system includes a flat getter disposed in the processing chamber.

U. S. Patent No. 6,299, 689 discloses the use of gettering materials in reflow chambers that incorporate a shielding film that prevents the flowing gettering material from reaching the material layer.

The above-mentioned patents disclose the use of gettering materials, but to further improve the brightness and luminous efficiency of the phosphor composition, it is possible to obtain unwanted atomic species during vacuum deposition of phosphor compositions for use in thick film dielectric electroluminescent displays. It is desired to provide an improved method for turing.

Summary of the Invention

The present invention is a method of minimizing and reducing the amount of oxygen, water and / or other unwanted atomic species from a vapor atmosphere in a deposition chamber in which a phosphor composition is deposited on a substrate. As such, this method is useful for minimizing and reducing the deposition of oxygen, water and / or other unwanted atomic species on and / or in phosphor compositions.

The method volatilizes or vaporizes using evaporation or sputtering techniques to form a getter film on the inner wall of the deposition chamber to getter unwanted atomic species that may be vaporized during vacuum deposition of the phosphor film compositions on the substrate. Providing getter species that can. Getter species are volatilized immediately before or simultaneously with the deposition of the phosphor film composition. Undesired atomic species in the process of the present invention are not co-volatile or at least co-volatile and therefore are not incorporated or minimally incorporated into the deposition phosphor compositions.

According to one aspect of the present invention, there is provided a method of minimizing generation of unwanted atomic species in a deposition chamber that performs deposition of phosphor film compositions on a substrate,

Simultaneously vaporizing one or more getter species immediately prior to and / or during deposition of the phosphor film compositions in the deposition chamber, wherein vaporization is performed in the chamber during vacuum deposition of the phosphor film compositions. A method is provided for continuously providing getter species that getter unwanted atomic species.

According to one aspect of the invention, in a method for minimizing the generation and deposition of oxygen, water and / or other unwanted atomic species in a deposition chamber that performs deposition of phosphor film compositions on a substrate,

Simultaneously vaporizing one or more getter species immediately prior to and / or during deposition of the phosphor film compositions in the deposition chamber, wherein the vaporization is oxygen, water and / or other desired in the deposition chamber. A method is provided for continuously gettering atomic species.

According to another aspect of the present invention, in a method for supplying a high surface area getter film by itself into a vacuum deposition chamber for deposition of phosphor film compositions, the getter species constituting the getter film are at a rate proportional to the generation of unwanted species to be adsorbed. Provided methods are provided.

According to another aspect of the present invention, a deposition method for deposition of thin film pre-determined phosphor compositions on a substrate in a deposition chamber, wherein the compositions are at least one element of groups IIA and IIB of the periodic table In a method comprising a tertiary, quaternary or higher sulfide compound selected from the group consisting of gallates and thioderites,

Volatilizing one or more getter species adjacent to at least one source comprising a sulfide to form the predetermined compositions, wherein the getter species are continuously deposited on interior surfaces of the deposition chamber. .

According to another aspect of the present invention, in a deposition method for the deposition of europium activated barium, thialuminate or free activated calcium thialuminate phosphor compositions on a substrate in a deposition chamber,

(a) volatilizing one or more sources collectively comprising phosphor compositions; And

(b) Immediately before (a) or concurrently with (a), a substantial internal surface area of a substantial portion of the deposition chamber to minimize their incorporation in the phosphor compositions and to remove and minimize unwanted atomic species from the deposition chamber. A method is provided that includes volatilizing one or more compact low surface area getter species to provide a high surface area getter film within.

Other features and advantages of the invention will be apparent from the following detailed description. However, while the embodiments of the present invention are shown, the detailed description and the specific embodiments are merely exemplary, and those skilled in the art will understand that various modifications and changes are possible within the spirit and scope of the present invention.

The invention will be fully understood from the following detailed description with reference to the accompanying drawings. The descriptions given herein are for illustrative purposes only and are not intended to limit the scope of the present invention.

1A and 1B are schematic diagrams showing a top view 1a and a side view 1b of a phosphor deposition chamber according to the present invention;

2 shows an excellent chemical compound formed from barium, oxygen and hydrogen at certain oxygen and water vapor partial pressures and temperatures;

3 shows the superiority of chemical compounds formed from titanium, oxygen and hydrogen at certain oxygen and water vapor partial pressures and temperatures;

4 is a graph showing the concentration of vapor species immediately before and during phospho deposition without the use of the getter material of the present invention; And

FIG. 5 is a graph showing the concentration of the deposition chamber immediately before and during phosphor deposition in accordance with the use of the method and getter material of the present invention. FIG.

The present invention is a method of controlling and minimizing the amount of oxygen, water and / or other unwanted vapor species in a deposition atmosphere to minimize incorporation into the phosphor compositions during vacuum deposition of the phosphor compositions. The method includes one or more getter species that are evaporated to provide a getter film on the inner walls of the deposition chamber immediately before and / or during deposition of the phosphor compositions. The getter film may be provided immediately prior to deposition of the phosphor compositions and / or may be provided continuously during the period in which the phosphor compositions are deposited on the substrate. Those skilled in the art will appreciate that a continuous installation of getter membranes is such as to provide such membranes progressively, continuously, leisurely and without substantial interruption.

This method feeds a high surface area getter film into the vacuum deposition chamber for deposition of phosphor film compositions at a rate proportional to the generation of unwanted vapor species to be adsorbed on their own. The present invention can overcome the limited capacity of getters of fixed capacity to adsorb vapor species at a reduced velocity as the deposition process proceeds and to adsorb unwanted vapor species. The present invention can also saturate the getters by overcoming the problem of getter inactivity when the deposition chamber is opened, thereby allowing the entry of oxygen and water vapor from the ambient atmosphere. The present invention can also overcome the problem of replenishing the fixed getter material and the problem of being deactivated by the species of phosphor compositions when the phosphor is deposited.

The deposition method of the present invention is in particular wherein the phosphor compositions are selected from the group consisting of thialuminates, thigallates, and thioidates of at least one element of groups IIA and IIB of the periodic table having a controlled surfer content. In this case, it is useful for the deposition of phosphor compositions on a substrate. Source materials for depositing the desired phosphor compositions include those selected from metals, alloys, intermediate metal compounds, sulfides, and surfer containing vapors that collectively contain elements comprising the deposited phosphor film compositions. According to an embodiment of the present invention, the deposited thin film compositions include glass activated barium, thialuminate phosphor compositions or europium activated calcium thialuminate phosphor compositions. Using the method of the present invention, phosphors having high luminance and useful luminescent colors are obtained.

In this method, one or more source materials that make up the compositions of the deposited phosphor are deposited on a suitable substrate using low pressure physical deposition methods such as, for example, electron beam evaporation, thermal evaporation or sputtering. Such physical deposition methods are known to those skilled in the art. Applicant's International Patent Application PCT CA01 / 01823 (herein reflects its entirety) by detecting and controlling the instantaneous change in the deposition of components on a substrate from the sources or sources used to form the deposited phosphor compositions Simultaneous deposition may be performed from sources or sources as taught within). A getter species or getter material is provided adjacent to the sources, thereby eliminating, preventing or minimizing the evaporation of excess surfer species, oxygen, water or other unwanted atomic species and, ultimately, into the deposited phosphor compositions. Can be eliminated, prevented or minimized. The getter species form a high surface area getter film on a substantial portion of the interior surface of the deposition chamber that vaporizes (volatiles) substantially adjacent to the sources and also provides a straight line of view to unwanted atomic species introduced into the deposition chamber. Deposition (i.e., condensation thereon) thereby increasing the likelihood that unwanted atomic species molecules are trapped (i.e. gettered) and immobilized when they contact the deposition chamber surface. Unwanted vapor atoms are to be understood to include, without limitation, oxygen, water, excess surfers, carbon dioxide, carbon monoxide, surfper monoxide, surfer dioxide, nitrogen molecules and other hydrogen-containing molecules. The method of the present invention is suitable for use with any standard of deposition chamber, as will be appreciated by those skilled in the art.

One skilled in the art will appreciate that one or more getter species may be provided in the deposition chamber in the method of the present invention. It is desirable to provide one or more getter species substantially adjacent to one or more sources that make up the compositions of the phosphor compositions to be deposited. Suitable getter species for use in the present invention include barium, metal; Metal as protected with barium, aluminum alloys, thin oxides, sulfates or sulfide surface layers; Titanium metals; Titanium sponge; Titanium-containing alloys, other getter materials generally known in the gettering art, and combinations thereof, but are not limited to these. The getter species are provided as pellets or targets that can be vaporized or sputtered in the deposition chamber. It will be appreciated that the getter species provided as pellets may also be provided as "unfixed pieces" of getter species for their evaporation. Thus, the present invention encompasses the use of pellets, chips and targets of getter species for vaporization / volatilization.

According to an embodiment of the invention, the getter species are supplied by thermal evaporation of barium metal or barium, aluminum alloy from barium or barium, aluminum alloy pellets. In order to facilitate the handling of barium, aluminum pellets, the intermediate metal compound BaAl ₄ in which the barium is sequestered within the crystal structure of the compound may be included in order to make it sufficiently inert in air so that it can be easily handled without oxidation. As the pellet is heated, steam is released and condensed on the walls of the deposition chamber to form a high surface area getter film, thereby maximizing the efficiency of the getter in removing unwanted vapor species from the deposition chamber. Barium evaporates at a rate proportional to the generation of oxygen, water vapor or other unwanted atomic species in such a way that such unwanted atomic species are adsorbed or reacted with the getter species. Oxygen and / or water vapor may be generated from sources used for phosphor film deposition as contaminants when injecting hydrogen sulfide into the deposition chamber to maintain an appropriate surfer pressure to form the desired sulfide phosphor films.

The method of the present invention produces a high surface area getter film in the deposition chamber from low surface area sources of getter material that can be easily handled in the atmosphere, resulting in reactions with oxygen, water and / or other vapor species that may be contained in the atmosphere. It can be manufactured and placed in a deposition chamber without chemical decay. Once the deposition chamber is evacuated just prior to deposition, low surface area getter species can be transformed into a high surface area getter film by a process of volatilization / vaporization and recondensation on the surface of the deposition chamber using physical deposition techniques. This can be done during and / or prior to vacuum deposition of the phosphor film compositions.

The getter film must cover a substantial portion of the interior surface of the deposition chamber to be effective in removing unwanted vapor plates from the deposition chamber. To limit the requirement, at or above the atmospheric temperature of the deposition chamber, the average heat rate V of the vapor molecules is given by the following equation. V = (3 kT / M) ^1/2 (where k is Boltzmann's constant, T is absolute temperature and M is vapor molecular mass). For steam molecules at normal ambient temperature, the speed is between about 100 meters per second for heavy molecules and about 2000 meters per second for hydrogen molecules. When the vacuum pressures typically used in deposition chamber processes are low, the average free path of vapor molecules is typically greater than 1 meter, so the impact that affects the vapor molecules is primarily deposition chambers for deposition chamber dimensions of about 1 meter. Occurs in those with surfaces. Correspondingly, the collision frequency between a single vapor molecule and the deposition chamber surface is in the range of 100 Hz to 1000 Hz. Therefore, in the case of a conventional 10 minute deposition, there will be a 60,000-600,000 collision between the vapor molecules heated and the deposition chamber surfaces during deposition if not gettered by the method of the present invention. The probability of vapor molecules gettered by the surface is the probability of being captured by a single collision and is proportional to the portion of the surface covered by the effective getter time. Assuming a 100% probability of being captured by the getter in a single collision, the portion of the deposition chamber surfaces covered by the getter is at least 1 / 60,000, or about, to getter most vapor species at a time compared to the deposition time. It should be 2 x 10 ^`-5 steradians. This translates to a need for a getter area of at least about 2 cm 2 in a substantially spheroidal deposition chamber of radius of 1 meter. If the probability of vapor molecules getting gettered in a single collision is 50% and you want to reduce the vapor concentration by a factor of 1000 at the time compared to the deposition time, at least 10 collisions per molecule are required, and the required getter area is at least 20 cm 2. Similarly, if the probability of vapor molecules getting gettered in a single collision is 30% and one wants to reduce the vapor concentration by a factor of 10,000, the required getter area is about 150 cm 2. One skilled in the art can further calculate as needed.

Typically the deposition chamber has internal surfaces therein that may include a removable shielding film to facilitate cleaning and other removable shielding films to control the direction of vapors emitted from the deposition sources or to manage deposition chamber temperature distribution. . As provided by the method of the invention, getter films covering these surfaces are very effective in gettering unwanted vapor atomic species. Because they show the highest collision probability for the vapor molecules. Therefore, it is desirable to control the getter deposition process to maximize the proportion of getter material deposited as getter films on these surfaces. In general, these inner surfaces are at a higher temperature than the walls of the external deposition chamber. Typically, getter species will not condense on surfaces whose saturated vapor pressure is at a temperature above the actual vapor pressure of the vaporized getter. Therefore, the temperature of the surface where getter condensation is required should be moderately low. If the temperature of the surface is below the temperature of the outer wall of the deposition chamber and there is a linear field of view between the surface and the sources of the volatilized getter film, most of the getter will condense there.

According to the embodiment of the present invention, since the getter material containing the thermal barium is positioned in such a manner that the thin film deposition substrate blocks the linear field from the getter material, there is almost no deposition of the barium on the vapor deposition substrate. However, in accordance with aspects of the present invention, upon depositing barium containing films, barium is deposited from the thermal getter material on the deposition substrate to incorporate barium into the deposition chamber's walls to act as a getter and into the chemical composition of the deposited film. It is desired to let.

According to another embodiment of the present invention, the barium-containing getter species may be a barium metal coated with a thin oxide, sulfate or sulfide surface layer to facilitate loading of the pellets in the deposition chamber to facilitate handling of the getter pellets in the atmosphere. .

According to another embodiment of the invention, the getter species may be titanium metal sputtered from a target comprising titanium or a titanium containing alloy. If titanium is unnecessary in the deposited film, the titanium sources should be placed in a non-linear field of view between the sources and the deposition substrate.

Getter species for evaporation or sputtering should be in a position in a straight line between the surfaces on which the getter is deposited during getter species evaporation or sputtering and phosphodeposition. If getter species are unnecessary as part of the phosphor compositions to be deposited, the getter species for evaporation or sputtering should be in a position other than the linear field of view between the getter species and the deposition substrate. The substrate may also be maintained at a temperature higher than the temperature of the surface at which the getter species are deposited so that condensation of the getter species on the deposited substrate is minimized.

For embodiments using a barium-containing getter material, the barium may getter oxygen and / or water and hydrogen depending on the temperature of the barium-containing film being deposited. Fig. 2 shows the main compound formed in the chemical equilibrium amount from barium oxygen and hydrogen as a function of oxygen and water vapor partial pressure and as a function of temperature. The partial pressure of water pH ₂ O is given as log ₁₀ (pH ₂ O) in barometric pressure, and the temperature is given in degrees Celsius. As can be seen in the figures, barium hydroxide and barium hydroxide are the main compounds of the steam partial pressure in the vacuum deposition atmosphere and at temperatures near normal ambient temperature. Within this condition, both water and oxygen must be effectively gettered by the barium metal to form these compounds and the like. At lower partial pressures and within the same temperature range, the main compound is BaO ₂ , which indicates that oxygen may be effectively gettered, but if it is gettered, water reacts with barium to form BaO ₂ , releasing hydrogen. Likewise, at higher temperatures BaO may be formed by the reaction of water and barium to release hydrogen.

For embodiments of the present invention using titanium getter species, oxygen may be gettered to form titanium oxide, but one or more streams have not been reported to readily form simultaneous gettering of oxygen and hydrogen or water. This is shown in the lead table shown in FIG.

The present invention provides for the deposition of thin film phosphors comprising rare earth activated thialuminates that achieve high energy efficiency and high brightness. This method maintains a ratio of 3 or 4, or more, elements that are tightly controlled to achieve optimal phosphor performance and are controlled to reduce the likelihood that the phosphor material may form into one or more crystalline phases. Can be used to deposit the phosphors in the form of tertiary or quaternary compounds. This method is also such as to ensure that the concentration of impurities such as oxygen is kept to a minimum.

The method of the present invention is a thin film phosphor having a range of phosphor compositions listed above that are incorporated into, for example, a thick film dielectric electroluminescent display as taught in US Pat. No. 5,432,015, which is hereby incorporated by reference in its entirety. Applicable to Phosphoric compositions may be activated with various impurities such as, for example, glass and ceramics.

The stoichiometry of the deposited phosphor compositions may be controlled, as disclosed in Applicant's PCT CA01 / 01823, which is hereby incorporated by reference in its entirety. Control of stoichiometry during deposition is carried out using two or more deposition sources having different chemical compositions, with deposition for at least two sources measuring the deposition rate for these sources regardless of the deposition rate of the remaining source material. This is done using a rate measurement system and a feedback system that controls the relative deposition rate in proportion to the measured rate.

The foregoing generally discloses the present invention. For a more complete understanding, reference may be made to the following specific examples. These examples are for illustrative purposes only and are not intended to limit the scope of the invention. Substitution of equivalents and changes in form may be arbitrarily contemplated, depending on the circumstances proposed or made. Although specific terms are used here, such terms are for illustrative purposes and not limitations.

Example

Referring to the cross-sectional view of FIG. 1, the modified Davis and Wilder 10SC-2836 vacuum deposition system was used for electron beam sources and aluminum sulfides for barium sulfide doped with 6 atomic% europium measured for atomic barium concentration (1). Electron beam sources for 2) were applied. Heat sources were provided for evaporation of barium aluminum (BaAl ₄ ) (3). On the sources there was provided a heated deposition substrate 4. A shielding film 5 having a ventilation window is provided to prevent a straight line view between the heat sources and the deposition substrate, but allows deposition of barium aluminum on a portion of the deposition chamber wall to act as a getter film during evaporation of materials from the electron beam sources. A thin film phosphor was formed on the plate. Residual gas analyzer 6 was connected to the vacuum chamber to search for vapor species in the deposition chamber. A pumping port 7 is provided to vacuum the deposition chamber using a diffusion pump, and an injection line 8 having a control valve 9 is provided to the surface of the doped barium sulfide source material 1 and aluminum sulfide. Both surfaces of the source material 2 are controlled in proportion to the desired operating pressure during vacuum deposition of the thin film in accordance with the method disclosed in Applicant's U.S. Provisional Patent Application No. 60 / 484,290, which is incorporated herein in its entirety. Hydrogen sulfide was injected into the deposition chamber at a rate.

An ion gauge 10 was installed to measure the pressure in the deposition chamber. A shutter 11 was placed in front of the europium doped barium sulfide electron beam sources 1 to prevent the doped barium sulfide from being deposited on the deposition substrate during heating, and the second shutter 12 was also made of an aluminum sulfide electron beam source. It was installed in front of the field 2 so that aluminum sulfide was not deposited on the deposition substrate while being heated. The quartz crystal monitor 13 was installed to detect the deposition rate of the doped barium sulfide, and the second quartz crystal monitor 14 was installed to detect the deposition rate of the aluminum sulfide, and the third quartz crystal monitor 15 was also installed. Was installed to detect the deposition rate of the getter material prior to the deposition of the phosphor film.

Doped barium sulfide and aluminum sulfide source materials were mounted in the deposition chamber. Then, the deposition chamber was pumped to a basic pressure of 0.1 mPa, and the deposition substrate was then heated to 325 ° C. After installing the shutters 7 in their closed positions, the Al ₂ S ₃ sources are approximately 160 mA (at 4.7 kV) and up to 85 mA (at 6.0 kV) on europium doped barium sulfide sources. Power was applied to the two electron beam sources (2) and (3) with a slowly increasing emission current over 25 minutes, as a result of which the temperature of the source materials was increased uniformly. As soon as full power was reached the shutters were opened to initiate deposition of the phosphor material on the heated substrate. For this deposition, no heat sources 3 were used nor heated.

4 shows the relative concentrations of vapor species measured while the source material is heated and during phospho deposition. As can be seen from the data, the concentrations of nitrogen, water and hydrogen were increased when the source material was heated. Before heating the source material, the partial pressure of water vapor was about 5 x 10 ^-4 Pa as measured by the residual gas analyzer. Was raised to the source material is heated to complete approximately 8 x10 ^-4 Pa immediately fell back to 5 x 10 ^-4 Pa. The rise during heating contributed to the degassing of the source materials as they melted. When deposition started, the water vapor pressure rose to 12 x 10 ^-3 Pa and then slightly dropped to 9 x 10 ^-4 Pa as the deposition proceeded. When the shutters were closed following deposition, the water vapor pressure dropped to about 6 x 10 ^-4 Pa. The power to the sources turned off and fell further when the sources cooled.

Example 2

Similar vacuum deposition as in Example 1 was carried out using heat sources 3 containing the intermediate metal compound BaAl ₄ . BaAl ₄ placed in the alumina source crucible was in the form of small pieces of about 2-3 millimeters in size. The heating of the heat sources 3 started about 10 to 15 minutes after the start of the initial pumpdown of the vacuum chamber. The evaporation rate of BaAl ₄ was measured using a quartz crystal monitor (15). The power to the heat sources was increased until the deposition rate was in the range of 1-3 angstroms per second. Then, power is applied to the electron beam sources (2) and (3), and the vapor pressure is raised to only 3 x 10 ^-4 Pa using a residual gas analyzer, then when deposition has started following the opening of the shutters. , The steam pressure was raised only to a value within the range of 3 × 10 ⁻⁴ Pa to 4 × 10 ⁻⁴ Pa. The factor of about 3 was lower than that of Example 1, which shows the efficiency of the getter in reducing the steam pressure.

While the preferred embodiments have been described so far, those skilled in the art will understand that various modifications and changes can be made without departing from the spirit of the invention or the appended claims.

Claims (23)

A method of minimizing the generation of unwanted atomic species in a deposition chamber that performs deposition of a phosphor film composition on a substrate, Simultaneously vaporizing one or more getter species in the deposition chamber immediately prior to and / or during deposition of the phosphor film compositions, And wherein said vaporizing step continuously provides getter species that getter unwanted atomic species in said deposition chamber during vacuum deposition of said phosphor film compositions. The method of claim 1, The getter species are vaporized and condensed onto an inner surface of the deposition chamber. The method of claim 2, And the getter species vaporize and condense on the interior surface of the deposition chamber showing a linear field of view for the unwanted atomic species. The method of claim 1, The getter species are vaporized and condensed onto removable shielding films provided in the deposition chamber. The method of claim 1, And said getter species are provided as pellets, targets or pieces. The method of claim 5, And said getter species are pellets. The method of claim 5, The getter species are targets sputtered in the deposition chamber. The method according to any one of claims 1 to 7, The getter species are barium metal; Barium aluminum alloy; Barium metal coated with a thin oxide, sulfate or sulfide surface layer; Titanium metal; Titanium sponge; Titanium-containing alloys and combinations thereof. The method of claim 8, Wherein said unwanted atomic species are selected from the group consisting of oxygen, water, excess surfers, carbon dioxide carbon monoxide, surfper monoxide, surfer dioxide, nitrogen molecules and other hydrogen containing molecules. The method of claim 2, The inner surface of the deposition chamber is maintained at a lower temperature than the outer walls of the deposition chamber. The method of claim 2, The getter species are further deposited on the substrate. The method of claim 11, And said getter species contain barium. The method of claim 11, Wherein said getter species are titanium metal. The method of claim 12, Wherein said phosphor film compositions comprise barium. The method according to any one of claims 1 to 14, And the substrate is provided at a higher temperature than the inner surface of the deposition chamber. The method according to any one of claims 1 to 15, Wherein said phosphor film compositions are selected from the group consisting of thialuminates, thiogallates and thioderites, which are at least one element of groups IIA and IIB of the periodic table. The method of claim 16, Wherein said phosphor film compositions comprise free activated barium thialuminate. The method of claim 16, Wherein said phosphor film compositions comprise free activated calcium thialuminate phosphor compositions. The method according to any one of claims 1 to 18, And the getter species are vaporized substantially adjacent to vaporized sources that make up the compositions of the phosphor film. The method according to any one of claims 1 to 19, Wherein said vaporizing of said getter species runs at a rate proportional to the production of unwanted species to be adsorbed. A method of minimizing the generation of water, oxygen and / or other unwanted atomic species in a deposition chamber that performs deposition of phosphor film compositions on a substrate, Simultaneously vaporizing one or more getter species in the deposition chamber immediately prior to and / or during deposition of the phosphor film compositions, And wherein said vaporizing step continuously getters said water, oxygen, and / or other unwanted atomic species in said deposition chamber. A deposition method for the deposition of thin film pre-determined phosphor compositions on a substrate in a deposition chamber, wherein the compositions are at least one element of groups IIA and IIB of the periodic table, such as thialuminates, thiogallates and thioderites. In a method comprising a tertiary, quaternary or higher sulfide compound selected from the group consisting of: Volatilizing one or more getter species adjacent to at least one source comprising sulfide to form the predetermined compositions, wherein the getter species are successively deposited on the inner surfaces of the deposition chamber. Way. A deposition method for the deposition of europium activated barium thialuminate or free activated calcium thialuminate phosphor compositions on a substrate in a deposition chamber, (a) volatilizing one or more sources collectively comprising phosphor compositions; And (b) immediately before (a) or concurrently with (a), the interior of a substantial portion of the deposition chamber to minimize their incorporation into the phosphor compositions and to remove and minimize unwanted atomic species from the deposition chamber. Volatilizing one or more compact low surface area getter species to provide a high surface area getter film within the surface area.

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