JP4155215B2 - Manufacturing method of electron source - Google Patents

Description

  The present invention relates to a method of manufacturing an electron source that emits an electron beam by field emission.

  Conventionally, as this type of electron source, for example, electron sources 10 ′ and 10 ″ configured as shown in FIGS. 4 and 5 are known.

  In the electron source 10 ′ configured as shown in FIG. 4, a strong electric field drift layer 6 ′ made of oxidized porous polycrystalline silicon is formed on the main surface (one surface) side of an n-type silicon substrate 1 as a conductive substrate. A surface electrode 7 made of a metal thin film (for example, a gold thin film) is formed on the strong electric field drift layer 6 ′. An ohmic electrode 2 is formed on the back surface of the n-type silicon substrate 1, and the n-type silicon substrate 1 and the ohmic electrode 2 constitute a lower electrode 12. In addition, the thickness dimension of the surface electrode 7 is set to about 10 nm, for example. Further, in the electron source 10 ′ having the configuration shown in FIG. 4, the non-doped polycrystalline silicon layer 3 is interposed between the lower electrode 12 and the strong electric field drift layer 6 ′, and the polycrystalline silicon layer 3 and the strong electric field drift are The layer 6 ′ constitutes an electron passage layer that is interposed between the lower electrode 12 and the surface electrode 7 and allows electrons to pass therethrough, but only the strong electric field drift layer 6 ′ without the polycrystalline silicon layer 3 being interposed. A structure in which an electron passage layer is formed is proposed.

  On the other hand, the electron source 10 ″ shown in FIG. 5 has the configuration shown in FIG. 4 in that the lower electrode 12 is formed of a metal film formed on one surface of an insulating substrate 11 made of an insulating glass substrate. Are the same, the same components as those of the electron source 10 ′ shown in FIG.

In order to emit electrons from the above-described electron sources 10 ′ and 10 ″, for example, a collector electrode 21 disposed opposite to the surface electrode 7 is provided, and a vacuum is applied between the surface electrode 7 and the collector electrode 21. A DC voltage Vps is applied between the surface electrode 7 and the lower electrode 12 so that the surface electrode 7 is on the high potential side with respect to the lower electrode 12, and the collector electrode 21 is on the high potential side with respect to the surface electrode 7. A DC voltage Vc is applied between the collector electrode 21 and the surface electrode 7. If the DC voltage Vps is appropriately set here, electrons injected from the lower electrode 12 cause the strong electric field drift layer 6 'to pass through. (The dashed line in FIGS. 4 and 5 indicates the flow of electrons e ⁻ emitted through the surface electrode 7.) Electrons reaching the surface of the strong electric field drift layer 6 ′ Is hot electro Believed to be, the surface electrodes 7 easily tunnel to be emitted into the vacuum.

  In each of the above-described electron sources 10 ′ and 10 ″, the current flowing between the surface electrode 7 and the lower electrode 12 is called a diode current Ips, and the current flowing between the collector electrode 21 and the surface electrode 7 is an emission current (emission). The electron current (Ie) is referred to as Ie (see FIGS. 4 and 5). As the ratio of the emission current Ie to the diode current Ips (= Ie / Ips) increases, the electron emission efficiency (= (Ie / Ips) × 100 [ Note that the above-described electron sources 10 ′ and 10 ″ emit electrons even when the DC voltage Vps applied between the surface electrode 7 and the lower electrode 12 is set to a low voltage of about 10 to 20V. The emission current Ie increases as the DC voltage Vps increases.

  By the way, as an electron source that emits an electron beam by field emission, various sources other than those described above have been proposed. For example, an MIM (Metal-Insulator) having an electron passage portion as an insulator layer is proposed. -Metal) electron sources, and MIS (Metal-Insulator-Semiconductor) structure electron sources with an electron passage portion as an insulator layer and a semiconductor layer interposed between the electron passage portion and the lower electrode have been proposed. Yes.

  In addition, as a display electron source, a large number of structures corresponding to an electron source element including the lower electrode 12, the electron passage layer, and the surface electrode 7 in the electron source 10 ″ having the configuration shown in FIG. An electron source having a formed configuration has also been proposed (see, for example, Patent Documents 1, 2, and 3).

  An electron source 10 shown in FIG. 6 is an example of an electron source for a display, and includes an insulating substrate 11 made of a glass substrate having an insulating property, and metals arranged on one surface of the insulating substrate 11. A plurality of strip-like lower wirings 12a made of a material, and a drift portion 6a made of a plurality of oxidized porous polycrystalline silicon layers formed so as to overlap the lower wiring 12a, and a non-doped structure that fills between the drift portions 6a A strong electric field drift layer 6 having a separation part 6b made of a polycrystalline silicon layer, a plurality of surface electrodes 7 stacked on each drift part 6a, and a strong electric field drift layer 6 formed on each surface electrode 7 respectively. The insulating layer 8 is provided with a corresponding portion opened, and a plurality of bus electrodes 25 are arranged on the insulating layer 8 in a direction intersecting (orthogonal to) the lower wiring 12a.

  Here, the bus electrode 25 is for commonly connecting a plurality of surface electrodes 7 arranged in a direction intersecting the lower wiring 12a for each column, and is located on the side of the surface electrode 7, From the side edge of each surface electrode 7, it extends to the surface of the bus electrode 25 along the surface of the insulating layer 8 and one side surface of the bus electrode 25 on the surface electrode 7 side, and the surface electrode 7 and the bus electrode 25 are electrically connected to each other. Connection wiring 16 to be connected is formed continuously and integrally. In other words, the connection wiring 16 extends from the side edge of the surface electrode 7 to the bus electrode 25 and electrically connects the surface electrode 7 and the bus electrode 25, and is simultaneously made of the same material as the surface electrode 7. It is integrally formed. The lower wiring 12a has pads 27 formed on both ends in the longitudinal direction. The bus electrodes 25 are connected to the pads 28 at both ends in the longitudinal direction. Since the bus electrode 25 does not need to tunnel electrons, the bus electrode 25 can be made thicker than the surface electrode 7 and the resistance can be reduced.

In the electron source 10 having the configuration shown in FIG. 6, a plurality of lower wirings 12 a arranged on one surface of the insulating substrate 11 and a plurality of surface electrodes 7 formed on the strong electric field drift layer 6. Since the drift portion 6a of the strong electric field drift layer 6 is sandwiched between them, the selected bus electrode is selected by appropriately selecting a set of the bus electrode 25 and the lower wiring 12a and applying a voltage between the selected sets. In FIG. 25, a strong electric field acts only on the drift portion 6a below the surface electrode 7 close to the portion corresponding to the intersection with the lower wiring 12a, and electrons are emitted. That is, the electron source 10 having the configuration shown in FIG. 6 includes the surface electrode 7, the drift portion 6a below the surface electrode 7, and the portion of the lower wiring 12a that overlaps the drift portion 6a and the surface electrode 7 (this portion is the lower portion in FIG. The number of the surface source electrodes 7 is the same as that of the surface electrode 7, and a desired electron source element is selected by selecting a set of the bus electrode 25 and the lower wiring 12a to which a voltage is applied. It becomes possible to emit electrons from. In the electron source 10 shown in FIG. 6, the strong electric field drift layer 6 constitutes an electron passage layer, and electrons pass through the drift portion 6 a in the electron passage layer from the lower wiring 12 a toward the surface electrode 7. A structure in which all of the electron passage layer is configured by the drift portion 6a has also been proposed.
JP 2000-188057 A JP 2002-343230 A Japanese Patent Laid-Open No. 2003-197088

  By the way, as a pattern formation method of the bus electrode 25 in the electron source 10 shown in FIG. 6, a formation method using lift-off or dry etching can be considered. When a shape abnormality occurs stochastically and such a shape abnormality of the bus electrode 25 occurs, the connection wiring 16 is disconnected as a result, and a conduction failure between the bus electrode 5 and the surface electrode 7 occurs. There was a problem that the reliability and operational stability of the electron source 10 were lowered, and a problem that the manufacturing yield was reduced and the manufacturing cost was increased.

  Hereinafter, an example of a method for manufacturing the electron source 10 will be described with reference to FIG. 7B to 7D show a case where the shape abnormality of the bus electrode 25 occurs.

First, a metal film for the lower wiring 12a is formed on one surface of the insulating substrate 11 by sputtering, vapor deposition, or the like, and then the metal film is patterned by using a photolithography technique and an etching technique. After forming a plurality of lower wirings 12a, a non-doped polycrystalline silicon layer covering the surface of each lower wiring 12a and a portion between adjacent lower wirings 12a is formed on the one surface side of the insulating substrate 11 by the CVD method. After the formation, the drift portion 6a is formed by subjecting the polycrystalline silicon layer to the portion where the drift portion 6a is to be formed by anodizing treatment and electrochemical oxidation treatment in sequence, and the strong electric field drift layer 6 is formed. An insulating layer 8 made of a SiO ₂ film is formed on the one surface side of the insulating substrate 11 by a CVD method or the like. By removing the portion corresponding to the site where the electrode 7 is to be formed using the photolithography technique and the etching technique, the structure shown in FIG. 7A is obtained.

  Next, the resist layer 9 having an opening pattern for forming the bus electrode 25 is formed on the one surface side of the insulating substrate 11, and then the material of the bus electrode 25 (for example, on the one surface side of the insulating substrate 11, for example, By forming the conductive layers 25a and 25b made of (aluminum) by vapor deposition, the structure shown in FIG. 7B is obtained. The opening portion of the resist layer 9 is formed in a reverse taper shape.

  Thereafter, the resist layer 9 and the conductive layer 25b on the resist layer 9 are removed by lift-off to form the bus electrode 25 composed of the remaining conductive layer 25a, whereby the structure shown in FIG. 7C is obtained.

  Next, a gold thin film is formed on the one surface side of the insulating substrate 11 by vapor deposition or the like, and the gold thin film is patterned by a photolithography technique and an ion milling technique to form the surface electrode 7 and the connection wiring 16. As a result, the structure shown in FIG.

  In FIG. 7 described above, when the conductive layers 25a and 25b are formed after the resist layer 9 having the opening pattern is formed, the shape of the conductive layer 25a is the same as that of the bus electrode 25 shown in FIG. Since the unnecessary protrusion (unnecessary protrusion) 26 protrudes abnormally compared to the normal shape (designed shape), the connection wiring 16 is disconnected as a result as shown in FIG. Yes.

  The bus electrode 25 connected to the surface electrode 7 through the connection wiring 16 as described above is not limited to the electron source 10 for display, and may be provided when used for other purposes.

  The present invention has been made in view of the above-mentioned reasons, and its object is to increase the manufacturing yield of an electron source including a bus electrode, and to improve the reliability and operational stability of the electron source. Is to provide.

  The invention according to claim 1 is formed on the surface of the lower electrode formed on one surface side of the substrate, the electron passage layer formed so as to cover the lower electrode on the one surface side of the substrate, and the surface of the electron passage layer. A surface electrode overlapping the lower electrode, a bus electrode located on the side of the surface electrode on the surface side of the electron passage layer and connected to the surface electrode, and from the side edge of the surface electrode along one side of the surface electrode side of the bus electrode A method of manufacturing an electron source including a connection wiring that is extended to the surface of the bus electrode and electrically connects the surface electrode and the bus electrode. In forming the bus electrode, the surface electrode, and the connection wiring, A resist layer having an opening pattern for bus electrode formation is formed on the one surface side, and then a conductive layer made of a bus electrode material is formed on the one surface side of the substrate, and then a resist layer is formed by lift-off. And cash register After forming the bus electrode composed of the remaining conductive layer by removing the conductive layer on the conductive layer, a smoothing process is performed to remove unnecessary protrusions protruding continuously from the bus electrode, and then the surface electrode and A connection wiring is formed.

  According to the present invention, even when an unnecessary protrusion protrudes from the portion that becomes the bus electrode when the conductive layer is formed after forming the resist layer having the opening pattern for forming the bus electrode, the surface electrode and the connection wiring Since unnecessary protrusions are removed by the smoothing process before formation, it is possible to suppress disconnection of the connection wiring due to the influence of the unnecessary protrusions and poor conduction between the bus electrode and the surface electrode. The manufacturing yield of the electron source can be increased, and the reliability and operational stability can be improved.

  The invention of claim 2 is formed on the surface of the lower electrode formed on one surface side of the substrate, the electron passage layer formed on the one surface side of the substrate so as to cover the lower electrode, and the surface of the electron passage layer. A surface electrode overlapping the lower electrode, a bus electrode located on the side of the surface electrode on the surface side of the electron passage layer and connected to the surface electrode, and from the side edge of the surface electrode along one side of the surface electrode side of the bus electrode A method of manufacturing an electron source including a connection wiring that is extended to the surface of the bus electrode and electrically connects the surface electrode and the bus electrode. In forming the bus electrode, the surface electrode, and the connection wiring, A conductive layer made of a bus electrode material is formed on the one surface side, and then a resist mask layer for forming a bus electrode is formed on the one surface side of the substrate, and then the resist mask layer is used as a mask to conduct electricity. Dry layer After forming a bus electrode composed of a conductive layer patterned by performing a smoothing process for removing unnecessary protrusions protruding from the bus electrode, a surface electrode and connection wiring are then formed. .

  According to the present invention, when the bus electrode is formed by dry etching the conductive layer using the resist mask layer as a mask, the bus electrode does not require a compound of the bus electrode material and the carbon-based material contained in the resist mask layer. Even if it protrudes as a protrusion, the unnecessary protrusion is removed by the smoothing process before the surface electrode and connection wiring are formed, so the connection wiring is disconnected due to the influence of the unnecessary protrusion, and there is a gap between the bus electrode and the surface electrode. It is possible to suppress the occurrence of poor conduction, increase the manufacturing yield of an electron source including a bus electrode, and improve reliability and operational stability.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, in the smoothing process, the unnecessary protrusion is removed by etching.

  According to the present invention, the unnecessary protrusion can be removed with good controllability.

  According to the first and second aspects of the invention, it is possible to increase the manufacturing yield of the electron source including the bus electrode, and to improve the reliability and operational stability.

(Embodiment 1)
Since the manufacturing method of the electron source in the present embodiment relates to the manufacturing method of the electron source 10 shown in FIG. 6, illustration and description of the configuration of the electron source 10 are omitted, and only the manufacturing method is described with reference to FIG. explain.

First, a metal film for the lower wiring 12a is formed on one surface of an insulating substrate 11 made of an insulating glass substrate by a sputtering method, a vapor deposition method, or the like, and then a photolithography technique and an etching technique are used. A plurality of lower wirings 12a are formed by patterning the metal film, and then a non-doped polycrystalline silicon layer is formed on the one surface side of the insulating substrate 11 by the CVD method. Among them, the drift region 6 a is formed by sequentially performing a nanocrystallization process and an oxidation process, which will be described later, on the site where the drift portion 6 a is to be formed, and the strong electric field drift layer 6 is formed. An insulating layer 8 made of a SiO ₂ film is formed on the side by a CVD method or the like, and corresponds to a portion where the surface electrode 7 is to be formed in the insulating layer 8 The structure shown in FIG. 1A is obtained by removing the portion using photolithography technology and etching technology. As shown in FIG. 2, the drift portion 6 a includes at least columnar polycrystalline silicon grains (semiconductor crystals) 51 arranged on the surface side of the lower wiring 12 a and a thin portion formed on the surface of the grains 51. A silicon oxide film 52, a number of nanometer-order silicon microcrystals (semiconductor microcrystals) 63 interposed between the grains 51, and a film formed on the surface of the silicon microcrystal 63 and smaller than the crystal grain size of the silicon microcrystal 63 It is considered that the silicon oxide film 64 is a thick insulating film. Each grain 51 extends in the thickness direction of the lower wiring 12a (that is, extends in the thickness direction of the insulating substrate 11). The arrows in FIG. 2 indicate the flow of electrons injected from the lower wiring 12a when a voltage is applied between the surface electrode 7 and the lower wiring 12a with the surface electrode 7 at the high potential side when the electron source 10 is driven. The electrons injected from the lower wiring 12 a are accelerated by a strong electric field applied to the silicon oxide film 64, drift in the region between the grains 51 in the drift portion 6 a toward the surface electrode 7, and pass through the surface electrode 7. Released.

  The steps after FIG. 1A will be described after describing the nanocrystallization process and the oxidation process described above.

In the above-described nanocrystallization process, for example, an electrolytic solution made of a mixed solution in which a 55 wt% aqueous hydrogen fluoride solution and ethanol are mixed at approximately 1: 1 is used, and the lower wiring 12a is used as an anode, and A constant current (a constant current (between the power source and the anode) is applied to the main surface of the polycrystalline silicon layer by irradiating the main surface of the polycrystalline silicon layer with a light source consisting of a 500 W tungsten lamp, with a cathode made of a platinum electrode facing the crystalline silicon layer. For example, by flowing a current having a current density of 12 mA / cm ² for a predetermined time (for example, 10 seconds), the first composite nanocrystal layer including the polycrystalline silicon grains 51 and the silicon microcrystals 63 is removed from the drift portion 6a. Formed in a region to be formed. In the above-described oxidation process, an electrolytic solution made of a solution obtained by dissolving 0.04 mol / l potassium nitrate in an organic solvent made of ethylene glycol is used, and the lower wiring 12a is used as an anode, and the first in the electrolytic solution. A cathode composed of a platinum electrode is placed opposite to the composite nanocrystal layer, the lower wiring 12a is used as an anode, and a constant current is supplied between the anode and the cathode from the power source (for example, a current density of 0.1 mA / cm ² ). And the first composite nanocrystal layer is electrochemically oxidized until the voltage between the anode and the cathode is increased by 20 V, whereby the grain 51, the silicon microcrystal 63, and the silicon oxide films 52 and 64 described above are oxidized. The drift part 6a which consists of a 2nd composite nanocrystal layer containing is formed. Here, the portion of the non-doped polycrystalline silicon layer 3 that fills the space between the adjacent drift portions 6a is the above-described separation portion 6b. In the present embodiment, in the first composite nanocrystal layer formed by performing the above-described nanocrystallization process, the regions other than the grains 51 and the silicon microcrystals 63 are amorphous regions made of amorphous silicon. In the drift portion 6a, regions other than the grains 51, the silicon microcrystals 63, and the silicon oxide films 52 and 64 are amorphous regions 65 made of amorphous silicon or partially oxidized amorphous silicon. Depending on the case, the amorphous region 65 becomes a hole, and the second composite nanocrystal layer in such a case can be regarded as having the same structure as the oxidized porous polycrystalline silicon layer similar to the conventional example. In the electron source 10 of the present embodiment, the insulating substrate 11 constitutes the substrate, the strong electric field drift layer 6 constitutes the electron passage layer, and the portion overlapping the drift portion 6a and the surface electrode 7 in the lower wiring 12a is the lower portion. It constitutes an electrode.

  Next, a process subsequent to FIG. 1A will be described. FIGS. 1B and 1C illustrate a case where a shape abnormality of the bus electrode 25 occurs.

  A resist layer 9 having an opening pattern for forming the bus electrode 25 is formed on the one surface side of the insulating substrate 11, and then the material of the bus electrode 25 (here, aluminum) is formed on the one surface side of the insulating substrate 11. By forming the conductive layers 25a and 25b made by vapor deposition, the structure shown in FIG. 1B is obtained. The opening portion of the resist layer 9 is formed in a reverse taper shape.

  Thereafter, the resist layer 9 and the conductive layer 25b on the resist layer 9 are removed by lift-off to form the bus electrode 25 composed of the remaining conductive layer 25a, whereby the structure shown in FIG. 1C is obtained. In the example shown in FIG. 1C, the shape of the conductive layer 25a formed through the opening of the resist layer 9 is the normal shape (design) of the bus electrode 25 shown in FIG. Compared to the upper shape), an unnecessary protrusion (unnecessary protrusion) 26 protrudes abnormally.

  Subsequently, the shape of the bus electrode 25 is normalized by performing a smoothing process for removing the unnecessary protrusions 26 that protrude continuously and integrally from the bus electrode 25 (the unnecessary protrusions 26 that cause disconnection of the connection wiring 16 are smoothed). As a result, the structure shown in FIG. Here, in the smoothing process, the unnecessary protrusions 26 made of aluminum are removed by wet etching, and the unnecessary protrusions 26 can be etched with good controllability. As the etchant, a positive photoresist developer mainly composed of a tetramethylammonium hydroxide aqueous solution (TMAH aqueous solution) is used.

  After performing the above-described smoothing treatment, a metal thin film (here, a gold thin film) is formed on the one surface side of the insulating substrate 11 by, for example, an electron beam evaporation method, and the metal thin film is formed by photolithography and Ar gas. By forming the surface electrode 7 and the connection wiring 16 by patterning using the ion milling technique used, the structure shown in FIG. In the present embodiment, as a method for forming the gold thin film, an electron beam evaporation method is adopted from the viewpoint of the film quality, film thickness controllability, and film forming cost of the gold thin film. The resist used as a mask material during ion milling is removed with an organic solvent or the like.

  According to the manufacturing method described above, when the conductive layers 25a and 25b are formed after the resist layer 9 having the opening pattern for forming the bus electrode is formed, the conductive layer 25a which is a portion that becomes the bus electrode 25 later. Even if the unnecessary protrusion 26 protrudes from the surface, the unnecessary protrusion 26 is removed by the smoothing process before the surface electrode 7 and the connection wiring 16 are formed. Therefore, it is possible to suppress the disconnection of the connection wiring 16 due to the influence of the unnecessary protrusions 26 formed during the manufacture or the poor conduction between the bus electrode 25 and the surface electrode 7. The manufacturing yield of the electron source 10 can be increased and the manufacturing cost can be reduced. Further, the electron source 10 manufactured by the above-described manufacturing method can improve reliability and operation stability as compared with the conventional case.

(Embodiment 2)
Since the method of manufacturing the electron source according to the present embodiment relates to the method of manufacturing the electron source 10 shown in FIG. 6, illustration and description of the configuration of the electron source 10 are omitted, and only the manufacturing method is described with reference to FIG. explain. Note that description of manufacturing steps similar to those of the first embodiment will be omitted as appropriate.

  First, a metal film for the lower wiring 12a is formed on one surface of the insulating substrate 11 by sputtering, vapor deposition, or the like, and then the metal film is patterned by using a photolithography technique and an etching technique. After forming the lower wiring 12a and then forming a non-doped polycrystalline silicon layer on the one surface side of the insulating substrate 11 by the CVD method, the drift portion 6a of the polycrystalline silicon layer is to be formed on the planned portion The drift portion 6 a and the strong electric field drift layer 6 are formed by sequentially performing the nanocrystallization process and the oxidation process described in the first embodiment, and the insulating layer 8 is formed on the one surface side of the insulating substrate 11. A portion of the insulating layer 8 corresponding to the formation site of the surface electrode 7 is formed by a CVD method or the like. By removing by utilizing techniques to obtain a structure shown in FIG. 3 (a).

  Next, a conductive layer made of the material of the bus electrode 25 (here, aluminum) is formed on the one surface side of the insulating substrate 11 by sputtering using Ar gas, and then the insulating substrate 11 is subjected to the above-described process. A resist mask layer 19 for forming a bus electrode is formed on one surface side, and then the bus electrode 25 made of the conductive layer patterned by dry etching the conductive layer using the resist mask layer 19 as a mask. By forming, the structure shown in FIG. Here, as an etching gas for performing dry etching of the conductive layer, for example, a mixed gas containing a chlorine component may be employed. Moreover, what is necessary is just to set the film thickness of the said electroconductive layer to about 300 nm-1200 nm, for example. Note that unnecessary protrusions (unnecessary protrusions 26) made of a compound of the bus electrode 25 material and the carbon-based material included in the resist mask layer 19 are formed on the sidewalls of the resist mask layer 19 from the bus electrode 25 immediately after the dry etching described above. Projecting along.

  Thereafter, the resist mask layer 19 is removed by a resist removal process using an oxygen plasma apparatus, whereby the structure shown in FIG. In the example shown in FIG. 3C, the shape of the bus electrode 25 protrudes from the unnecessary protrusion 26 as compared with the normal shape (designed shape) of the bus electrode 25 shown in FIG. Abnormal shape.

  Subsequently, by performing a smoothing process for removing the unnecessary protrusions 26 protruding from the bus electrode 25, the shape of the bus electrode 25 is normalized (smoothing the unnecessary protrusions 26 that cause the disconnection of the connection wiring 16). The structure shown in FIG. Here, in the smoothing process, the unnecessary protrusions 26 made of aluminum are removed by wet etching, and the unnecessary protrusions 26 can be etched with good controllability. As the etchant, a positive photoresist developer mainly composed of a TMAH aqueous solution is used.

  After performing the above-described smoothing treatment, a metal thin film (here, a gold thin film) is formed on the one surface side of the insulating substrate 11 by, for example, an electron beam evaporation method, and the metal thin film is formed by photolithography and Ar gas. The surface electrode 7 and the connection wiring 16 are formed by patterning using the used ion milling technique, whereby the structure shown in FIG.

  According to the manufacturing method described above, when the bus electrode 25 is formed by dry-etching the conductive layer serving as the base of the bus electrode 25 using the resist mask layer 19 of the conductive layer as a mask, Even when a compound of the bus electrode 25 material and the carbon-based material included in the resist mask layer 19 protrudes as an unnecessary protrusion 26, the unnecessary protrusion 26 is smoothed before the surface electrode 7 and the connection wiring 16 are formed. Is removed. Therefore, it is possible to suppress the disconnection of the connection wiring 16 due to the influence of the unnecessary protrusions 26 formed during the manufacture or the poor conduction between the bus electrode 25 and the surface electrode 7. The manufacturing yield of the electron source 10 can be increased and the manufacturing cost can be reduced. Further, the electron source 10 manufactured by the above-described manufacturing method can improve reliability and operation stability as compared with the conventional case.

  By the way, in the manufacturing method described in each of the above embodiments, the example in which aluminum is employed as the material of the bus electrode 25 has been described. However, the material of the bus electrode 25 is not limited to aluminum, and for example, tungsten, chromium, molybdenum, copper Other metals such as gold may be used.

  Moreover, although the example which employ | adopted the developing solution which has TMAH aqueous solution as a main component was demonstrated as an etching liquid used in a smoothing process, generally used acidic solution, alkaline solution, etc. can also be used as etching liquid. Therefore, it may be selected appropriately according to the material of the bus electrode 25. However, when the material of the bus electrode 25 is aluminum, it is preferable to employ the above-mentioned developer from the viewpoint of relatively slowing the etching rate.

  In addition, the smoothing process when aluminum is used as the material of the bus electrode 25 is not limited to wet etching, and for example, heat treatment in an inert gas atmosphere such as nitrogen may be performed. As the heat treatment conditions, the heat treatment temperature may be 500 ° C. or higher, and the heat treatment time may be about 10 to 60 minutes. Of course, when a metal material other than aluminum is adopted as the material of the bus electrode 25, the heat treatment temperature and the heat treatment time may be appropriately set according to the material characteristics of the metal material.

  In addition, as the smoothing treatment, dry etching such as chemical etching using plasma in a reactive gas or physical etching using plasma in an inert gas may be employed, or etching using plasma is employed. In this case, by applying a negative voltage to the bus electrode 25, the unnecessary protrusions 26 can be effectively removed in a shorter time.

  In each of the above embodiments, the method for manufacturing the electron source 10 shown in FIG. 6 has been exemplified. However, the structure of the electron source 10 is not particularly limited, and a portion corresponding to each of the electron source elements is, for example, an MIM type. It is also possible to employ a configuration in which a MIS type electron source is provided.

FIG. 5 is a main process cross-sectional view for explaining the electron source manufacturing method according to the first embodiment. It is principal part explanatory drawing of the electron source in the same as the above. FIG. 6 is a main process cross-sectional view for explaining an electron source manufacturing method according to Embodiment 2. It is operation | movement explanatory drawing of the field emission type electron source which shows a prior art example. It is operation | movement explanatory drawing of the field emission type electron source which shows another prior art example. The electron source for the display which applied the same is shown, (a) is a schematic perspective view, (b) is a principal part cross section. It is principal process sectional drawing for demonstrating the manufacturing method of an electron source same as the above.

Explanation of symbols

6 Strong electric field drift layer 6a Drift part 7 Surface electrode 8 Insulating layer 9 Resist layer 10 Electron source 11 Insulating substrate 12a Lower wiring 16 Connection wiring 25 Bus electrode 25a Conductive layer 25b Conductive layer 26 Unnecessary protrusion

Claims (3)

  A lower electrode formed on one surface side of the substrate, an electron passage layer formed to cover the lower electrode on the one surface side of the substrate, and a surface electrode formed on the surface of the electron passage layer and overlapping the lower electrode; A bus electrode located on the side of the surface electrode on the surface side of the electron passage layer and connected to the surface electrode; and extending from the side edge of the surface electrode to the surface of the bus electrode along one side surface of the bus electrode on the surface electrode side A method of manufacturing an electron source comprising a connection wiring for electrically connecting a surface electrode and a bus electrode, wherein the bus electrode, the surface electrode and the connection wiring are formed on the one surface side of the substrate by the bus electrode. A resist layer having an opening pattern for formation is formed, and then a conductive layer made of a bus electrode material is formed on the one surface side of the substrate, and then the resist layer and the conductivity on the resist layer are formed by lift-off. layer After forming the bus electrode made of the remaining conductive layer by removing, a smoothing process is performed to remove unnecessary protrusions protruding continuously and integrally from the bus electrode, and then the surface electrode and the connection wiring are formed. A method for manufacturing an electron source.   A lower electrode formed on one surface side of the substrate, an electron passage layer formed to cover the lower electrode on the one surface side of the substrate, and a surface electrode formed on the surface of the electron passage layer and overlapping the lower electrode; A bus electrode located on the side of the surface electrode on the surface side of the electron passage layer and connected to the surface electrode; and extending from the side edge of the surface electrode to the surface of the bus electrode along one side surface of the bus electrode on the surface electrode side A method of manufacturing an electron source comprising a connection wiring for electrically connecting a surface electrode and a bus electrode, wherein the bus electrode, the surface electrode and the connection wiring are formed on the one surface side of the substrate by the bus electrode. A conductive layer made of the above material is formed, then a resist mask layer for forming a bus electrode is formed on the one surface side of the substrate, and then the conductive layer is dry-etched using the resist mask layer as a mask. By After forming a bus electrode made of a patterned conductive layer, a smoothing process is performed to remove unnecessary protrusions protruding from the bus electrode, and then a surface electrode and a connection wiring are formed. Method.   3. The method of manufacturing an electron source according to claim 1, wherein, in the smoothing process, the unnecessary protrusion is removed by etching.

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