JP5055723B2 - LIGHT EMITTING DEVICE, ITS MANUFACTURING METHOD, AND ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to a structure for emitting light from a light emitting layer and a technique for producing the structure.

  2. Description of the Related Art Conventionally, a light emitting device in which elements (hereinafter referred to as “unit elements”) in which a light emitting layer made of a light emitting material such as an organic EL (ElectroLuminescent) material is interposed between a first electrode and a second electrode is arranged on a substrate has been conventionally Proposed. In this type of light emitting device, there is a problem that it is difficult to ensure sufficient color reproducibility when employed as a display device, for example, because the peak width of the spectrum of emitted light by the light emitting layer is wide and the intensity thereof is low. .

In order to solve this problem, for example, Patent Document 1 discloses a configuration in which a resonator structure for resonating light emitted from a light emitting layer is formed in each unit element. In this configuration, a reflective layer (dielectric mirror) is disposed between the substrate and the light transmissive first electrode located on the substrate side with respect to the light emitting layer. The outgoing light from the light emitting layer reciprocates between the reflective layer and the second electrode facing each other across the light emitting layer. Then, light having a resonance wavelength corresponding to the optical distance between the reflective layer and the second electrode is selectively amplified and then emitted to the observation side. Therefore, light having a narrow spectrum peak width and high intensity can be used for display, and thereby, color reproducibility of the display device can be improved. Further, light having wavelengths corresponding to a plurality of colors (for example, red, green, and blue) can be extracted by adjusting the optical distance between the reflective layer and the second electrode for each unit element.
International Publication No. 01/039554 Pamphlet

  By the way, in the above structure, it is necessary to form a 1st electrode so that the reflective layer formed in the surface of a board | substrate may be coat | covered. Therefore, for example, there is a problem that the surface of the reflective layer is damaged (corroded) due to adhesion of an etching solution used for patterning the first electrode. As the material of the reflective layer, metals such as aluminum and silver are preferably employed. However, since this type of material has low corrosion resistance, damage and deterioration due to the etching solution are particularly remarkable. And when the reflection characteristic (for example, reflectance) of a reflective layer deteriorates by such damage, there exists a problem that the efficiency of resonance by a resonator structure falls. This invention is made | formed in view of such a situation, and it aims at the solution of the subject of preventing degradation of a reflection layer.

In order to solve this problem, a light-emitting device according to the present invention includes a first unit element that generates light having a wavelength corresponding to a first color on a substrate, and a second unit different from the first color. A second unit element that generates light having a wavelength corresponding to the color of the first unit element, wherein the first unit element and the second unit element are disposed on the substrate. One reflective layer, a light transmissive layer disposed on the first reflective layer, one or more light transmissive conductive films, an electrode disposed on the light transmissive layer, and the electrode A light emitting layer that generates light of a corresponding wavelength, and a second reflection that is disposed on the light emitting layer and forms a resonance region that resonates light from the light emitting layer with the first reflective layer. A layer, wherein the first unit element and the second unit element are arranged in the resonance region of the electrode. Wherein the number of layers of conductive film are different.
According to this configuration, the resonance wavelength is determined according to the number of conductive films in the resonance region of each unit element. Therefore, for example, when the number of conductive films of the electrode of the first unit element is maximized and the number of conductive films of the electrode of the second unit element is minimized, the resonance wavelength of the first unit element Is longer than the resonance wavelength of the second unit element, and the resonance wavelength of each unit element can be adjusted for each emission color.
A wiring disposed on the substrate and covered with the light-transmitting layer; and a contact hole disposed in the light-transmitting layer on the wiring, wherein the electrode of the first unit element includes a first electrode A first layer comprising a conductive film and including a portion disposed in the resonance region, a first layer including a portion in contact with the wiring through the contact hole, and a first layer disposed on the first layer of the first unit element; And a second layer including a portion disposed in the resonance region, wherein the electrode of the second unit element is formed of the first conductive film, and is formed through the contact hole. A first conductive portion including a portion in contact with the wiring and a second conductive film disposed on the first conductive portion, including a portion disposed in the resonance region and a portion in contact with the first conductive portion. A second layer, and in the second unit element, The vibration region may be configured in which the first conductive film is not provided.

  According to this configuration, since the light transmissive layer is formed so as to cover the first reflective layer, it is possible to prevent the first reflective layer from being deteriorated or damaged during the formation of the electrode of each unit element. Further, since the first conductive portion is formed so as to contact the wiring through the contact hole of the second unit element, the first conductive film is selectively removed and the second conductive film is selectively removed. The situation where the wiring of the unit element 2 is deteriorated or damaged is effectively prevented.

  In order to efficiently emit light from each unit element, at least one of the first reflective layer and the second reflective layer is a film body (semi-transmissive reflective layer) having both light transmittance and light reflectivity. It is desirable to be. If the first reflective layer is a semi-transmissive reflective layer, a bottom emission type light emitting device that emits light from the substrate side is realized. If the second reflective layer is a semi-transmissive reflective layer, light is emitted from the opposite side of the substrate. A top emission type light emitting device is realized. The second reflective layer may also be used as an electrode for applying an electric field to the light emitting element, or an electrode may be formed separately from the second reflective layer.

  In a preferred aspect of the present invention, the electrode of the first unit element is formed by selectively removing the second conductive film, and is interposed between the light emitting layer and the first reflective layer and is electrically connected to the first layer. Two layers (for example, the second layer 262 of the unit element Ur in FIG. 1) are included. According to this aspect, the optical distance between the first reflective layer and the second reflective layer (and hence the resonant wavelength in the resonator structure) can be easily and reliably made different between the first unit element and the second unit element. Can do.

  In a more desirable mode, a portion (for example, the second layer 262 in FIG. 1) of the electrode of each unit element is a portion formed from the first conductive film of the electrode of the unit element ( For example, the side end surfaces of the first layer 261 and the first conductive portion 271 in FIG. 1 are covered. According to this aspect, it is possible to prevent deterioration and damage of the portion formed from the first conductive film when selectively removing the second conductive film.

  In a more specific aspect, a third unit element (for example, unit element Ub in FIG. 1) having a resonance wavelength different from that of the first unit element and the second unit element among the plurality of unit elements. The electrode is formed by selectively removing the first conductive film, and contacts the wiring through the contact hole (for example, the first conductive part 271 of the unit element Ub in FIG. 1) and the second conductive A second conductive part (for example, the second conductive part 272 of the unit element Ub in FIG. 1) formed by selective removal of the film and conducted to the first conductive part, and a second film formed after the second layer is formed. A third layer formed by selective removal of the three conductive films and interposed between the light emitting layer and the first reflective layer and conducting to the second conducting portion (for example, the third layer 263 of the unit element Ub in FIG. 1) Including. According to this aspect, it is possible to realize three types of light emission colors by easily and reliably differentiating the resonance wavelengths of the first to third unit elements.

  In this aspect, the electrode of at least one of the first unit element and the second unit element is formed by selectively removing the third conductive film, and is formed between the light emitting layer and the first reflective layer. 3 (for example, the third layer 263 of the unit element Ur and the third layer 263 of the unit element Ug in FIG. 1) interposed therebetween. According to this configuration, the optical distance between the first reflective layer and the second reflective layer (and hence the resonant wavelength in the resonator structure) can be easily made different between each of the first to third unit elements.

  More preferably, a portion of the electrode of each unit element formed from the third conductive film (for example, the third layer 263 in each unit element U of FIG. 1) is the first conductive film or the first of the unit element electrodes. A side end face of a portion formed of two conductive films (for example, the first layer 261 or the second layer 262, the first conductive portion 271 or the second conductive portion 272 in each unit element U in FIG. 1) is covered. According to this aspect, it is possible to prevent the portion formed from the first conductive film or the second conductive film from being deteriorated or damaged when the third conductive film is selectively removed.

  The light emitting device according to the present invention is used in various electronic devices. A typical example of this electronic device is a device that uses a light emitting device as a display device. Examples of this type of electronic device include a personal computer and a mobile phone. However, the use of the light emitting device according to the present invention is not limited to image display. For example, the light emitting device of the present invention can also be applied as an exposure device (exposure head) for forming a latent image on an image carrier such as a photosensitive drum by irradiation of light. For example, the light-emitting device of the present invention can be employed as a lighting device (backlight) installed on the back surface of the liquid crystal panel.

  The method for manufacturing a light emitting device according to the present invention includes a first reflective layer disposed on the surface of the substrate, a second reflective layer disposed on the opposite side of the substrate across the first reflective layer, and a first reflective layer A resonator that includes a plurality of unit elements each including a light emitting layer interposed between the first reflective layer and the second reflective layer, and resonates light emitted from the light emitting layer between the first reflective layer and the second reflective layer A method of manufacturing a light emitting device having a structure formed on each unit element, wherein a wiring forming step (for example, step A1 in FIG. 2) for forming a wiring on a surface of a substrate, and a first reflective layer of each unit element are formed. A reflective layer forming step (for example, step A3 in FIG. 2) formed on the surface of the substrate, and a translucent layer having a contact hole for each unit element in a portion overlapping with the wiring so as to cover the wiring and the first reflective layer A light-transmitting layer forming step (for example, step A4 in FIG. 2) formed of a light-transmitting insulating material; A first film forming step (for example, step A5 in FIG. 3) for forming a first conductive film (for example, the conductive film L1 in FIG. 3) covering the layers, and a light emitting layer of the first unit element among the plurality of unit elements; A first layer interposed between the first reflective layer and contacting the wiring through a contact hole corresponding to the first unit element; and a resonance wavelength in the resonator structure of the plurality of unit elements is the first A first removal step of forming collectively a first conductive portion that contacts a wiring through a contact hole corresponding to a second unit element different from the unit element by selective removal of the first conductive film ( For example, step A6) in FIG. 3 and a second film forming step (for example, step A7 in FIG. 3) for forming a second conductive film (for example, conductive film L2 in FIG. 3) covering the first layer and the first conductive portion. And between the light emitting layer and the reflective layer of the second unit element and the first conductor And a second removal step (for example, step A8 in FIG. 3) of forming a second layer conducting to the through portion by selectively removing the second conductive film.

  In this manufacturing method, since the translucent layer is formed so as to cover the first reflective layer, it is possible to prevent the first reflective layer from being deteriorated or damaged during the formation of the electrode of each unit element. Further, since the first conductive portion is formed so as to contact the wiring through the contact hole of the second unit element, the first conductive film is selectively removed and the second conductive film is selectively removed. The situation where the wiring of the unit element 2 is deteriorated or damaged is effectively prevented. In addition, the order in which each of a wiring formation process and a reflection layer formation process is implemented is arbitrary.

  More preferably, in the second removal step, a second layer interposed between the light emitting layer of the first unit element and the first reflective layer is formed by selectively removing the second conductive film. According to this aspect, the optical distance between the first reflective layer and the second reflective layer can be easily and reliably made different between the first unit element and the second unit element.

  Further, in the second removal step, the second element is formed such that the portion formed from the second conductive film in each unit element covers the side end surface of the portion formed from the first conductive film in the unit element. The conductive film may be selectively removed. According to this aspect, when removing the second conductive film, it is possible to prevent damage and breakage of each part formed from the first conductive film.

  In the first removal step, among the plurality of unit elements, wiring is performed through a contact hole corresponding to a third unit element whose resonance wavelength in the resonator structure is different from that of the first unit element and the second unit element. A first conductive portion that contacts is formed by selectively removing the first conductive film, and a third conductive film that covers the substrate (for example, the conductive film L3 in FIG. 3) is formed after the second removal step. A film process (for example, step A9 in FIG. 3) and a third layer interposed between the light emitting layer and the first reflective layer of the third unit element and conducting to the first conduction part of the third unit element. And a third removal step (for example, step A10 in FIG. 3) formed by selective removal of the third conductive film. According to this aspect, the resonance wavelengths of the first to third unit elements can be easily and surely made different while preventing the deterioration and damage of the wiring of each unit element.

  In the third removal step, a third layer interposed between the light emitting layer and the first reflective layer of at least one of the first unit element and the second unit element is formed as a third conductive film. It may be formed by selective removal. According to this aspect, the optical distance between the first reflective layer and the second reflective layer can be easily and reliably made different in each of the first to third unit elements.

  More preferably, in the third removal step, a portion formed from the third conductive film in each unit element covers a side end face of a portion formed from the first conductive film or the second conductive film in the unit element. Thus, the third conductive film is selectively removed. According to this aspect, it is possible to prevent the portion formed from the first conductive film or the second conductive film from being deteriorated or damaged when the third conductive film is selectively removed.

<A: Structure of light emitting device>
FIG. 1 is a cross-sectional view showing the structure of a light emitting device according to an embodiment of the present invention. As shown in the figure, the light emitting device D has a configuration in which a plurality of unit elements U (Ur, Ug, Ub) arranged in a matrix are sealed on the surface of the substrate 10 by a sealing material 37. ing. Each unit element U is an element that generates light having a wavelength corresponding to one of a plurality of colors (red, green, and blue). That is, the unit element Ur emits red light (R), the unit element Ug emits green light (G), and the unit element Ub emits blue light (B). The light emitting device D in the present embodiment is a top emission type in which light generated in each unit element U is emitted toward the side opposite to the substrate 10 (upward in FIG. 1). Therefore, an opaque plate material such as a ceramic or metal sheet as well as a light-transmitting plate material such as glass can be used as the substrate 10.

  A plurality of wirings 12 are formed on the surface of the substrate 10. These wirings 12 are wirings (for example, data lines and scanning lines) that transmit signals for driving the unit elements U, and are formed in stripes by a conductive material such as copper along the arrangement of the unit elements U. It is formed. The surface of the substrate 10 on which the wirings 12 are formed is covered with a base layer 14. The underlayer 14 is a film body formed of various insulating materials such as a resin material such as acrylic or epoxy, or an inorganic material such as silicon oxide (SiOx) or silicon nitride (SiNx).

  A light reflecting layer 21 is formed on the surface of the base layer 14 so as to correspond to each unit element U. The light reflecting layer 21 in the present embodiment is formed in a stripe shape so as to follow the arrangement of the unit elements U. Each light reflecting layer 21 is made of a material having light reflectivity. As such a material, there are various materials such as a single metal such as aluminum or silver, or an alloy mainly composed of aluminum or silver.

  The surface of the base layer 14 on which the light reflecting layer 21 is formed is covered with a light transmitting layer 23 that is continuously distributed over a plurality of unit elements U. The light transmitting layer 23 is a film body used for protecting the light reflecting layer 21 and is formed of a light transmitting insulating material such as silicon oxide (SiOx) or silicon nitride (SiNx). A contact hole H penetrating the light-transmitting layer 23 and the base layer 14 in each thickness direction is formed for each unit element U at a position overlapping the wiring 12 when viewed from the direction perpendicular to the surface of the substrate 10. The translucent layer 23 may be formed on the surface of the light reflecting layer 21 by, for example, anodizing the light reflecting layer 21.

  On the surface of the substrate 10 on which the light transmissive layer 23 is formed, the first electrodes 25 (25r, 25g, 25b) are formed so as to be separated from each other for each unit element U. Each first electrode 25 is formed of a light-transmitting conductive material such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). From the viewpoint of preventing the refraction and reflection at the boundary surface between the light transmission layer 23 and the first electrode 25 from being substantially equal, the first electrode 25 is formed of ITO and the light transmission is performed. A configuration in which the layer 23 is formed of silicon nitride is desirable.

  The film thickness of the region overlapping with the light reflecting layer 21 in each first electrode 25 (hereinafter referred to as “resonance region”) is different for each emission color of the unit element U. The film thickness of the resonance region in the present embodiment is determined for each emission color of the unit element U according to the number of laminated film bodies constituting each first electrode 25. The specific structure of each first electrode 25 is as follows.

  The first electrode 25r of the red unit element Ur is formed of a first layer 261, a second layer 262, and a third layer 263 that are formed so as to overlap each other (that is, distributed in the resonance region). Three layers are stacked in this order from the substrate 10 side. On the other hand, the first electrode 25g of the green unit element Ug is formed only in the vicinity of the contact hole H and formed so as to overlap the light reflecting layer 21 with the first conductive portion 271 that is not distributed in the resonance region. The second layer 262 and the third layer 263 are stacked in this order from the substrate 10 side. Further, the first electrode 25b of the blue unit element Ub is formed only in the vicinity of the contact hole H and is not distributed in the resonance region, and the light reflecting layer 21 and the first conductive portion 271 and the second conductive portion 272 are distributed. The third layer 263 formed so as to overlap is laminated in this order from the substrate 10 side. Therefore, the film thickness in the resonance region is the unit in which the first electrode 25r of the unit element Ur in which the three layers from the first layer 261 to the third layer 263 are stacked is maximized, and only the first layer 261 is distributed in the resonance region. The first electrode 25b of the element Ub is minimized.

  The first electrode 25r of the unit element Ur is electrically connected to the wiring 12 when the first layer 261 enters the contact hole H and contacts the wiring 12. Further, the first conductive portion 271 is formed in the contact hole H in the first electrode 25g (second layer 262 and third layer 263) of the unit element Ug and the first electrode 25g (third layer 263) of the unit element Ub. By entering and contacting the wiring 12, the wiring 12 is electrically connected. Each first conductive portion 271 enters the contact hole H from the surface of the light transmitting portion 23 and covers a portion of the wiring 12 exposed from the contact hole H.

  The first layer 261 of the unit element Ur and the first conductive portions 271 of the unit element Ug and the unit element Ub are collectively formed by patterning a single conductive film (conductive film L1 in FIG. 3). The second layer 262 of each of the unit element Ur and the unit element Ug and the second conductive portion 272 of the unit element Ub are collectively formed by patterning a single conductive film (conductive film L2 in FIG. 3). . Further, the third layer 263 of all the unit elements (Ur, Ug, Ub) is collectively formed by patterning a single conductive film (conductive film L3 in FIG. 3).

  Each layer (the first layer 261 and the second layer 262, the first conduction part 271 and the second conduction part 272) constituting the first electrode 25 of each unit element U has both a surface and a side end face over the entire circumference. It is covered by each part located in the upper layer. For example, the second layer 262 of the red unit element Ur is formed to have a larger area than the first layer 261 positioned below the red unit element Ur, and covers both the surface (upper surface) and side end surfaces of the first layer 261. That is, the side end face of the first layer 261 (the edge portion in the direction perpendicular to the substrate 10) is covered with the second layer 262 over the entire circumference. Similarly, the second layer 262 in the unit element Ur is covered with the third layer 263 on both the surface and the side end face. Further, in the first electrode 25g of the green unit element Ug, a second layer 262 is formed so as to cover both the surface and the side end face of the first conducting portion 271, and further the surface and the side end face of the second layer 262. Is coated on the third layer 263. Further, in the first electrode 25b of the blue unit element Ub, a second conductive portion 272 is formed so as to cover the surface and side end surfaces of the first conductive portion 271. Further, the surface and side end surfaces of the second conductive portion 272 are formed. A third layer 263 is formed to cover the surface.

  A bank layer 31 is formed on the surface of the substrate 10 on which the first electrode 25 is formed. The bank layer 31 is a partition wall formed in a lattice shape so as to partition the space on the surface of the substrate 10 for each unit element U. The bank layer 31 is formed of various insulating materials such as an acrylic or epoxy resin material or an inorganic material such as silicon oxide or silicon nitride.

  A light emitter 33 is formed for each unit element U in a space (concave portion) surrounded by the inner wall of the bank layer 31 and having the first electrode 25 as a bottom surface. The light-emitting body 33 has a structure in which a plurality of functional layers including a light-emitting layer made of an organic EL material are stacked. The light emitter 33 of each unit element U includes a light emitting layer that emits light of a wavelength corresponding to the unit element U. The first electrode 25 of each unit element U functions as an anode for applying electric energy to the light emitter 33. On the other hand, a second electrode 35 that functions as the cathode of the light emitter 33 is formed on the surface of each light emitter 33. However, the first electrode 25 may function as a cathode and the second electrode 35 may function as an anode.

  The light-emitting body 33 in the present embodiment has a structure in which three types of functional layers, a hole transport layer, a light-emitting layer, and an electron transport layer, are stacked in this order from the substrate 10 side to the second electrode 35 side. However, the structure of the light emitter 33 is not limited to this example. For example, a configuration in which a hole injection layer is interposed between the hole transport layer and the first electrode 25 or a configuration in which an electron injection layer is interposed between the electron transport layer and the second electrode 35 may be employed. In other words, a configuration in which a light emitting layer is interposed between the first electrode 25 and the second electrode 35 is sufficient.

  The second electrode 35 functions as a transflective layer having a property of transmitting a part of the light reaching the surface and reflecting the rest (that is, transflective). The second electrode 35 in the present embodiment is formed of a light transmissive material such as ITO. Thus, even if the second electrode 35 is made of a light-transmitting material, if the sealing material 37 is formed of a material having a refractive index lower than that of the second electrode 35, the second electrode 35 and the sealing material Since part of the light is transmitted and the other part is reflected at the interface with 37, the second electrode 35 can function as a transflective layer. Even when the light-reflective material such as aluminum or silver (or an alloy containing these metals as a main component) is formed thin to form the second electrode 35, the second electrode 35 is used as a semi-transmissive reflective layer. Can function.

  Each unit element U is an element including a light reflecting layer 21, a light transmitting layer 23, a first electrode 25, a light emitter 33, and a second electrode 35. In each unit element U, a resonator structure for resonating light emitted from the light emitting layer is formed between the light reflecting layer 21 and the second electrode 35. In other words, the light emitted from the light emitting layer of the light emitter 33 reciprocates between the light reflecting layer 21 and the second electrode 35, and only the component of the resonance wavelength in the resonator structure is selectively amplified, and then the second electrode 35. Is transmitted to the observation side. Therefore, according to the present embodiment, light having a narrow spectrum peak width and high intensity can be used for display.

The resonance wavelength λ in the resonator structure is determined according to the optical distance L between the light reflection layer 21 and the second electrode 35 as expressed by the following formula (1). However, “Φ (rad)” in the equation (1) is a phase shift that occurs at both ends of the resonator structure, and more specifically, a phase shift Φ1 that occurs when the light is reflected on the surface of the light reflecting layer 21. (Rad) and the sum (Φ = Φ1 + Φ2) of phase shifts Φ2 and (rad) generated when the light is reflected from the surface of the second electrode 35. “M” is an integer that makes the optical distance L positive.
(2L) / λ + Φ / (2π) = m (1)
By substituting the desired resonance wavelength λ to be emitted from each unit element U into the equation (1), the optical distance L for realizing optical resonance by this resonance wavelength λ is determined.

  Now, among the elements existing in the gap between the light reflecting layer 21 and the second electrode 35, the refractive index and the film thickness of the light emitting body 33 and the light transmitting layer 23 are substantially the same regardless of the emission color of each unit element U. Assuming that, the resonance wavelength is determined according to the film thickness in the resonance region of the first electrode 25 of each unit element U. Therefore, as shown in FIG. 1, when the film thickness (the number of stacked layers) of the first electrode 25r of the unit element Ur is maximized and the film thickness of the first electrode 25b of the unit element Ub is minimized, the unit element Ur It is possible to adjust the resonance wavelength of each unit element U for each emission color such that the resonance wavelength is longer than the resonance wavelength of the unit element Ug and the resonance wavelength of the unit element Ug is longer than the resonance wavelength of the unit element Ub. it can.

<B: Manufacturing method>
Next, a method for manufacturing the light emitting device D of the present embodiment will be described with reference to FIGS. Each layer shown below is formed by various known film forming techniques such as sputtering, CVD (Chemical Vapor Deposition), and vapor deposition. For patterning each layer, for example, a photolithography technique and an etching technique are used.

  First, a plurality of wirings 12 are formed on the surface of the substrate 10 (step A1 in FIG. 2). Subsequently, the base layer 14 is formed on the surface of the substrate 10 (step A2). Next, the light reflecting layer 21 is formed by patterning the light reflecting film formed over the entire surface of the substrate 10 (step A3). Next, the light-transmitting layer 23 is formed by patterning the insulating layer formed to a thickness of about 50 nm so as to cover the entire surface of the substrate 10 (step A4).

  Next, a conductive film L1 is formed to a thickness of about 40 nm over the entire surface of the substrate 10 (step A5 in FIG. 3). The conductive film L 1 enters the contact hole H of the light transmitting layer 23 and contacts the wiring 12. As the material of the conductive film L1, a conductive material having optical transparency such as ITO or IZO is preferably employed. Subsequently, the first layer 261 of the unit element Ur, the unit element Ug, and the first conductive portion 271 of the unit element Ub are collectively formed by patterning the conductive film L1 (step A6). The first layer 261 is distributed so as to enter the contact hole H and overlap the light reflecting layer 21. On the other hand, the first conductive portion 271 is distributed only in the vicinity of the contact hole H and does not overlap the light reflecting layer 21.

  Next, an ITO or IZO conductive film L2 is formed to a thickness of about 30 nm over the entire surface of the substrate 10 (step A7). Then, the second layer 262 of each of the unit element Ur and the unit element Ug and the second conductive portion 272 of the unit element Ub are collectively formed by patterning the conductive film L2 (step A8). Each part (the second layer 262 and the second conductive part 272) formed from the conductive film L2 has a side end face of each part (the first layer 261 and the first conductive part 271) formed from the conductive film L1 in each lower layer. Cover the entire circumference.

  Further, a conductive film L3 of ITO or IZO is formed to a thickness of about 30 nm over the entire surface of the substrate 10 (step A9). Then, the third layer 263 of each unit element U (Ur · Ug · Ub) is collectively formed by patterning the conductive film L3 (step A10). The third layer 263 formed from the conductive film L3 includes portions (first layer 261 and second layer 262, first conductive portion 271 and second conductive portion) formed from the conductive film L1 and the conductive film L2 in the respective lower layers. 272) is covered over the entire circumference.

  Subsequently, the bank layer 31 is formed by forming a resin film and patterning the resin film (step A11 in FIG. 4). Further, in the space for each unit element U partitioned by the bank layer 31, the light emitter 33 including the light emitting layer of the emission color corresponding to the unit element U is sequentially formed (step A12). Next, a translucent second electrode 35 is formed so as to face the first electrode 25 with each light emitter 33 interposed therebetween (step A13), and then a sealing material 37 is formed so as to cover the entire surface of the substrate 10. Is installed (see FIG. 1).

  As described above, in the present embodiment, since the light reflecting layer 21 is covered with the light transmitting layer 23 prior to the formation of the first electrode 25, the conductive films L1 to L3 are patterned (step A6 and step A8). The etching solution used in step A10) does not adhere to the light reflecting layer 21. Therefore, according to the present embodiment, the light reflecting layer 21 is prevented from being deteriorated or damaged, and a good resonator structure in which the light emitted from the light emitter 33 is used with high efficiency can be realized.

  By the way, from the viewpoint of making each of the first electrodes 25 different in thickness for each light emitting color of each unit element U and conducting each with the wiring 12, only the first conducting portion 271 and the second conducting portion 272 are provided. A non-forming method (hereinafter referred to as “proportional”) may also be employed. FIG. 5 is a process diagram of the manufacturing method of the light emitting device D according to the comparison. Steps B5 to B10 in FIG. 5 are performed in place of steps A5 to A10 in FIG.

  First, the first layer 261 of the unit element Ur is formed by forming the conductive film L1 (step B5 in FIG. 5) and patterning the same (step B6). As shown in FIG. 5, in the proportional method, the portion corresponding to the unit element Ug and the unit element Ub of the conductive film L1 is completely removed (that is, the first conduction part 271 is not formed). The wiring 12 is exposed through the contact hole H corresponding to the unit element Ug and the unit element Ub. Therefore, in the process B6, the etching solution used for patterning the conductive film L1 may adhere to the unit elements Ug and the wirings 12 corresponding to the unit elements Ub, and these wirings 12 may be damaged or deteriorated.

  Subsequent to the step B6, the second layer 262 of each of the unit element Ur and the unit element Ug is formed by the formation of the conductive film L2 (step B7) and the patterning (step B8). In the comparative method, since the second conductive portion 272 corresponding to the unit element Ub is not formed, the wiring 12 is exposed through the contact hole H corresponding to the unit element Ub in step B8. Therefore, there is a possibility that the wiring 12 of the unit element Ub is deteriorated or damaged by the adhesion of the etching used in the step B8. Next, the third layer 263 of each unit element U (Ur · Ug · Ub) is formed by forming the conductive film L3 (step B9) and patterning the same (step B10).

  As described above, in the comparative method in which the first conductive portion 271 and the second conductive portion 272 are not formed, there is a problem that the wiring 12 is deteriorated by the adhesion of the etching solution through the contact hole H. Since the wiring 12 of the unit element Ub in which the first electrode 25 is composed only of the third layer 263 is eroded by the etching solution twice in the process B6 and the process B8, the damage and deterioration thereof are particularly remarkable. On the other hand, in the present embodiment, the contact hole H corresponding to the unit element Ug and the unit element Ub is blocked by the first conduction part 271 and the second conduction part 272 (that is, the wiring 12 is the first conduction part 271 and the second conduction part 271). The etching solution used for patterning the conductive film L1 or L2 does not adhere to the wirings 12 of these unit elements U from the second conductive portion 272). Therefore, the deterioration and breakage of the wiring 12 of any unit element U can be prevented. Further, in the present embodiment, the first conductive portion 271 of the unit element Ug and the unit element Ub is formed from the conductive film L1 that is first formed and patterned among the conductive films L1 and L2. Compared with the configuration in which only the portion 272 is formed, there is an advantage that deterioration and damage of the wiring 12 corresponding to the unit element Ub can be surely prevented.

  5, the second layer 262 covers only the surface of the first layer 261 and the third layer 263 covers only the surface of the second layer 262 (that is, the first layer 261 and the first layer 261). A configuration in which the side end surface of the two layers 262 is exposed is illustrated. In such a configuration, when the conductive film L2 is etched in the step B8, the etching solution adheres to the side end face (the portion denoted by E1 in FIG. 5) of the first layer 261 of the unit element Ur, and the first layer 261. May deteriorate or be damaged. Similarly, the side surfaces of the first layer 261 and the second layer 262 (portion E2 in FIG. 5) of the unit element Ur and the second layer 262 of the unit element Ug are etched during the etching of the conductive film L3 in the process B10. There is a possibility that the etching solution adheres to the side end face (the part denoted by E2 in FIG. 5), and these parts are deteriorated or damaged.

  On the other hand, in this embodiment, each part (the second layer 262 and the second conduction part 272) formed from the conductive film L2 is replaced with each part (the first layer 261 and the first conduction part) formed from the conductive film L1. 271) is completely covered up to the side end face, so that the etching solution used in step A8 does not adhere to the first layer 261 or the first conductive portion 271. Similarly, since each part (third layer 263) formed from the conductive film L3 completely covers the side end surfaces of the respective parts formed from the conductive film L1 and the conductive film L2, the etching solution used in step A10 is used. Does not adhere to the first layer 261, the second layer 262, the first conduction part 271 and the second conduction part 272. Therefore, according to the present embodiment, it is possible to effectively prevent deterioration and damage of the first layer 261 and the second layer 262, the first conduction unit 271 and the second conduction unit 272.

  Further, in the configuration in which the side end surfaces of the respective layers of the first electrode 25 are exposed as shown in FIG. 5 (particularly, step B10), the side end surfaces of the respective layers of the first electrode 25 are on the same plane (perpendicular to the substrate 10). In a flat plane). Therefore, the step D corresponding to the film thickness of each first electrode 25 is steep with respect to the surface of the light transmitting layer 23. Thus, the location where the shape of the surface changes rapidly becomes a singular point of the electric field (location where the electric field concentrates). Current leakage is likely to occur. On the other hand, in the present embodiment, each layer of the first electrode 25 is formed so as to cover up to the side end surface of the lower layer, so that the peripheral edge of the first electrode 25 is shown, for example, as step A10 in FIG. This portion is a step D that is gently inclined with respect to the surface of the light transmitting layer 23. Therefore, according to the present embodiment, the concentration of the electric field in the vicinity of the periphery of the first electrode 25 is reduced as compared with the proportional configuration, thereby suppressing the deterioration of the first electrode 25 and the light emitter 33 and the leakage of current. There is an advantage that you can.

<C: Modification>
Various modifications can be made to the above embodiment. An example of a specific modification is as follows. In addition, you may combine each following aspect suitably.

(1) Modification 1
The elements constituting the unit element U may be formed continuously over the plurality of unit elements U, or may be formed separately from each other for each unit element U. For example, at least one functional layer of the light emitter 33 and the second electrode 35 may be continuously distributed over the plurality of unit elements U. Even if the light emitting layer is configured to be continuous over all the unit elements U, the light emission color of each unit element U can be made different by appropriately selecting the resonance wavelength of each unit element U. Further, the light reflecting layer 21 and the light transmitting layer 23 may be continuously distributed over the plurality of unit elements U.

(2) Modification 2
In the above embodiment, the configuration in which the second electrode 35 is also used as the transflective layer of the resonator structure is illustrated, but the transflective layer may be formed separately from the second electrode 35. The transflective layer in this configuration may be disposed on the light emitter 33 side with respect to the second electrode 35, or may be disposed on the opposite side (observation side). In the above embodiment, the top emission type light emitting device D has been exemplified. However, the present invention is also applied to a bottom emission type light emitting device. In the bottom emission type light-emitting device, the second electrode 35 shown in FIG. 1 is formed of a light-reflective conductive material so that it can also be used as a light-reflecting layer, and instead of the light-reflecting layer 21 shown in FIG. A semi-transmissive reflective layer may be formed.

(3) Modification 3
In the above embodiment, the configuration in which the wiring 12 is formed for each arrangement of the unit elements U is illustrated. However, in the configuration in which the potential of the second electrode 35 is controlled for each unit element U, all the unit elements The U first electrode 25 may be commonly connected to the single wiring 12. Moreover, it is good also as a structure by which the separate wiring 12 was formed for every unit element U. FIG. That is, the correspondence between the first electrode 25 of each unit element U and the wiring 12 can be arbitrarily changed.

(4) Modification 4
In the above embodiment, the configuration in which the first electrode 25b of the unit element Ub includes the first conduction part 271, the second conduction part 272, and the third layer 263 is illustrated, but the second conduction part 272 is appropriately omitted. The This is because if the first conductive portion 271 is formed (even if the second conductive portion 272 is not provided), the effect of preventing damage and deterioration of the wiring 12 is certainly achieved. That is, in the first electrode 25b, the third layer 263 may be formed so as to be in direct contact with the first conduction part 271.

(5) Modification 5
As shown in FIG. 6, color filters 41 (41 r, 41 g, 41 b) of colors (red, green, and blue) corresponding to the emission colors of the unit elements U may be installed. In the same figure, the case where the color filter 41 of each color is formed in the surface of the board | plate material 40 which has a light transmittance is illustrated. The color filter corresponding to each unit element U is means for selectively transmitting light having a wavelength corresponding to the resonance wavelength of the unit element U. For example, a color filter that transmits light corresponding to red is installed on the observation side of the red unit element Ur. According to this configuration, only the component that has passed through the color filter out of the light emitted from each unit element U is emitted to the observation side, so that the color reproducibility can be improved as compared with the configuration in which the color filter is not installed. Moreover, since external light is absorbed by each color filter, there is an advantage that reflection of external light is reduced.

(6) Modification 6
In the above embodiment, the film thickness of the first electrode 25 (and thus the optical distance between the first electrode 25 and the second electrode 35 in the resonance base structure) is determined according to the number of stacked conductive films. Although different configurations are illustrated for each, it is not always necessary that the resonance region of the first electrode 25 is a plurality of layers. For example, the first electrode 25 of the unit element Ur is formed only from the first layer 261, the first electrode 25 of the unit element Ug is formed only from the first conduction part 271 and the second layer 262, and the first of the unit element Ub is formed. Even when the electrode 25 is formed only from the first conductive portion 271 and the second conductive portion 272 and the third layer 263, the film thicknesses of the first layer 261, the second layer 262, and the third layer 263 ( That is, if the film thickness of each of the conductive films L1 to L3) is adjusted individually, the film thickness of each first electrode 25 can be made different for each emission color of the unit element U.

(7) Modification 7
The material of each part which comprises the light-emitting device D, and the method of manufacturing each are changed arbitrarily. For example, in each embodiment, a light emitting layer made of an organic EL material has been exemplified. However, the present invention is similarly applied to a light emitting device including a light emitting layer made of an inorganic EL material or a light emitting device using a light emitting diode as a light emitter. Can be applied.

<D: Application example>
Next, an electronic apparatus using the light emitting device according to the present invention will be described. FIG. 7 is a perspective view showing the configuration of a mobile personal computer that employs the light emitting device D according to any one of the embodiments described above as a display device. The personal computer 2000 includes a light emitting device D as a display device and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002.

  FIG. 8 shows a configuration of a mobile phone to which the light emitting device D according to the embodiment is applied. A cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and a light emitting device D as a display device. By operating the scroll button 3002, the screen displayed on the light emitting device D is scrolled.

  FIG. 9 shows a configuration of a personal digital assistant (PDA) to which the light emitting device D according to the embodiment is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and a light emitting device D as a display device. When the power switch 4002 is operated, various kinds of information such as an address book and a schedule book are displayed on the light emitting device D.

  Electronic devices to which the light emitting device according to the present invention is applied include those shown in FIGS. 7 to 9, digital still cameras, televisions, video cameras, car navigation devices, pagers, electronic notebooks, electronic papers, and calculators. , Word processors, workstations, videophones, POS terminals, printers, scanners, copiers, video players, devices equipped with touch panels, and the like. Further, the use of the light emitting device according to the present invention is not limited to the display of images. For example, the light emitting device of the present invention can be used as a backlight of a liquid crystal panel.

It is sectional drawing which shows the structure of the light-emitting device which concerns on embodiment of this invention. It is process drawing for demonstrating the manufacturing method of a light-emitting device. It is process drawing for demonstrating the manufacturing method of a light-emitting device. It is process drawing for demonstrating the manufacturing method of a light-emitting device. It is process drawing for demonstrating the manufacturing method of the light-emitting device which concerns on contrast. It is sectional drawing which shows the structure of the light-emitting device which concerns on a modification. It is a perspective view which shows the specific form of the electronic device which concerns on this invention. It is a perspective view which shows the specific form of the electronic device which concerns on this invention. It is a perspective view which shows the specific form of the electronic device which concerns on this invention.

Explanation of symbols

D: Light emitting device, U (Ur, Ug, Ub): Unit element, 10: Substrate, 12: Wiring, 14: Underlayer, H: Contact hole, 21: Light reflection layer, 23 ... ... Translucent layer, 25 (25r, 25g, 25b) ... 1st electrode, 261 ... 1st layer, 262 ... 2nd layer, 263 ... 3rd layer, 271 ... 1st conduction | electrical_connection part, 272 ... ... 2nd conduction | electrical_connection part, 31 ... Bank layer, 33 ... Light-emitting body, 35 ... 2nd electrode, 37 ... Sealing material.

Claims (8)

A light-emitting device including a first unit element that generates light having a wavelength corresponding to a first color on a substrate,
The first unit element is
A first reflective layer disposed on the substrate;
A light transmissive layer disposed on the first reflective layer and formed of a light transmissive insulating material ;
An electrode composed of a plurality of light-transmitting conductive films and disposed on the light-transmitting layer;
A light emitting layer disposed on the electrode and generating light of a corresponding wavelength;
A second reflective layer that is disposed on the light emitting layer and forms a resonance region in which light from the light emitting layer resonates with the first reflective layer;
The plurality of conductive films include a first layer and a second layer that is formed in a larger area than the first layer and covers a surface of the first layer on the light emitting layer side and a side end surface of the first layer. A light emitting device characterized by that. A second unit element disposed on the substrate for generating light of a wavelength corresponding to a second color different from the first color;
A wiring disposed on the substrate and covered with the light-transmitting layer ;
The second unit element is
A first reflective layer disposed on the substrate;
A light transmissive layer disposed on the first reflective layer and formed of a light transmissive insulating material ;
An electrode composed of a plurality of light-transmitting conductive films and disposed on the light-transmitting layer;
A light emitting layer disposed on the electrode and generating light of a corresponding wavelength;
A second reflective layer that is disposed on the light emitting layer and forms a resonance region in which light from the light emitting layer resonates with the first reflective layer;
The plurality of conductive films include a first layer and a second layer that has a larger area than the first layer and covers a surface of the first layer on the light emitting layer side and a side end surface of the first layer. ,
A first contact hole is formed in the translucent layer on the wiring of the first unit element ;
A second contact hole is formed in the translucent layer on the wiring of the second unit element ;
Wherein the first layer of the electrode of the first unit element is made of a first conductive film, viewing including the portion in contact with the wiring through the a portion disposed in said resonance region first contact hole ,
Wherein the second layer of the first unit element is made of a second conductive film disposed on the first layer, seen including a portion disposed in said resonance region,
The first layer of the electrode of the second unit element includes a first conductive portion that includes a portion that is made of a first conductive film and that is in contact with the wiring through the second contact hole;
The second layer of the second unit element is made of a second conductive film disposed on the first conductive portion, and includes a portion disposed in the resonance region and a portion in contact with the first conductive portion. See
2. The light emitting device according to claim 1, wherein, in the second unit element, the first conductive film is not provided in the resonance region. A third unit element that generates light having a wavelength corresponding to a third color different from the first color and the second color;
The third unit element is
A first reflective layer disposed on the substrate,
A light transmissive layer disposed on the first reflective layer and formed of a light transmissive insulating material ;
An electrode made of a light-transmitting conductive film and disposed on the light-transmitting layer;
A light emitting layer disposed on the electrode and generating light of a corresponding wavelength;
A second reflective layer that is disposed on the light emitting layer and forms a resonance region in which light from the light emitting layer resonates with the first reflective layer;
A third contact hole is formed in the translucent layer,
The electrode of the third unit element is
A first conductive portion comprising the first conductive film and including a portion in contact with the wiring through the contact hole;
A second conductive portion comprising the second conductive film and including a portion in contact with the first conductive portion;
A third layer comprising a third conductive film disposed on the second conductive portion, including a portion disposed in the resonance region and a portion in contact with the second conductive portion;
The second layer of the third unit element is formed in a larger area than the first layer of the third unit element, and the light emitting layer side surface of the first layer of the third unit element And covering the immediate end surface of the first layer of the third unit element,
The electrode of the first unit element is
A third layer comprising the third conductive film disposed on the second layer of the first unit element and including a portion disposed in the resonance region;
The electrode of the second unit element is
A third layer comprising the third conductive film disposed on the second layer of the second unit element and including a portion disposed in the resonance region;
In the third unit element, a light-emitting device according to claim 1 or 2, wherein the resonance region, characterized in that said first conductive film and the second conductive film is not provided. 4. The light emitting device according to claim 1, wherein a cross section of an end portion of the electrode of each of the first to third unit elements is stepped. 5. The electronic device which comprises the light-emitting device in any one of Claims 1-4 . A first unit element that generates light of a wavelength corresponding to a first color on a substrate, and a second unit element that generates light of a wavelength corresponding to a second color different from the first color A method of manufacturing a light emitting device comprising:
A first reflective layer forming step of forming a first reflective layer on the substrate;
Forming a light-transmitting layer formed of a light-transmitting insulating material on the first reflective layer; and
An electrode forming step comprising a light-transmitting conductive film and forming an electrode on the light-transmitting layer;
A light emitting layer forming step of forming a light emitting layer for generating light of a corresponding wavelength on the electrode;
A second reflective layer forming step of forming a second reflective layer on the light emitting layer to form a resonance region for resonating light from the light emitting layer with the first reflective layer;
The electrode forming step includes
A first film forming step of forming a first conductive film on the light transmitting layer;
A first layer including a portion disposed in the resonance region in the first unit element; and a first conduction portion including a portion in which the portion disposed in the resonance region in the second unit element is selectively removed. And a first removal step of selectively removing the first conductive film;
A second film forming step of forming a second conductive film on the first layer and the first conductive portion;
A second layer including a portion disposed in the resonance region in the first unit element; a second layer including a portion disposed in the resonance region in the second unit element; and a portion in contact with the first conduction portion. And a second removal step of selectively removing the second conductive film so as to cover a side end surface of a portion of the electrode formed from the first conductive film. A method for manufacturing a light emitting device. A wiring forming step of forming wiring on the substrate before the light transmitting layer forming step;
The method for manufacturing a light emitting device according to claim 6 , wherein the translucent layer forming step includes a step of forming a contact hole in a portion overlapping with the wiring. The first removal step includes
Forming a portion in contact with the wiring through the contact hole in the first layer of the first unit element;
Forming a portion in contact with the wiring through the contact hole in the first conduction portion of the second unit element;
A portion of the third unit element that generates light having a wavelength corresponding to a third color different from the first color and the second color, wherein a portion disposed in the resonance region is selectively removed; Forming a first conductive portion including a portion that contacts the wiring via the contact hole,
The second removal step includes
Forming a second conductive portion including a portion in which the portion arranged in the resonance region in the third unit element is selectively removed and a portion in contact with the first conductive portion;
further,
A third film forming a third conductive film on the second layer of the first unit element, the second layer of the second unit element, and the second conduction portion of the third unit element. Process,
A third layer including a portion disposed in the resonance region in the first unit element; a third layer including a portion disposed in the resonance region in the second unit element; and the third unit element. And a portion of the unit element formed from the third conductive film includes the third layer including the portion disposed in the resonance region, and the portion of the unit element includes the first conductive film or the second conductive film. emission of claim 6 or claim 7, characterized in that it comprises a third removal step of forming by selective removal of the serial third conductive film so as to cover the side end surface of the portion formed from the film Device manufacturing method.

Images