JP2018010829A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device having a light-receiving element, and a method for manufacturing the same.SOLUTION: There is provided a display device comprising a substrate, a pixel located on the substrate and including a sub-pixel and a sensing element, and a passivation film on the pixel. The sub-pixel comprises a first light-emitting element configured so as to emit light through the passivation film. The sensing element comprises a second light-emitting element configured so as to emit light through the substrate, and a light-receiving element configured so as to receive the light made incident through the substrate. Each of the first light-emitting element and the second light-emitting element comprises a pixel electrode, a light-emitting layer on the pixel electrode, and a counter electrode on the light-emitting layer. The counter electrode may be shared by the first light-emitting element and the second light-emitting element.SELECTED DRAWING: Figure 7

Description

  One embodiment of the present invention relates to a display device having a light receiving element.

  In recent years, display devices equipped with a touch panel have been widely used. By installing a touch panel, it is possible to input information directly through the screen of the display device to an electronic device such as a mobile phone or a personal computer without requiring the assistance of mechanical input devices such as a keyboard and input buttons. . The touch panel is classified into a resistance film method, a capacitance method, an optical method, and the like depending on a difference in operation principle. In the case of the optical system, since sensing can be performed using light of various wavelengths, not only can sensing be performed without directly touching the screen, but also static biological information such as fingerprints, palm prints, veins, etc. Dynamic biological information such as pulse waves (changes in blood vessel volume) can also be sensed and measured. Patent Documents 1 and 2 disclose a display device on which an optical touch panel is mounted. In these display devices, a photodiode as a light receiving element is incorporated in a pixel responsible for display together with a light emitting element and a liquid crystal element.

Japanese Patent Laid-Open No. 2007-300087 JP 2009-0669493

  One of the problems of the embodiments of the present invention is to provide a display device having a light receiving element and a manufacturing method thereof. Or it is providing the display apparatus which has a function which acquires biometric information, and the method of producing it at low cost.

  One embodiment of the present invention is a display device including a substrate, a pixel located on the substrate, having a sub-pixel and a sensing element, and a passivation film on the pixel. The sub-pixel has a first light emitting element configured to emit light through the passivation film. The sensing element has a second light emitting element configured to provide light emission through the substrate and a light receiving element configured to receive light incident through the substrate.

  One embodiment of the present invention is a display device including a substrate, a pixel located on the substrate, having a sub-pixel and a sensing element, and a passivation film on the pixel. The subpixel has a first light emitting element configured to emit light through the substrate. The sensing element has a second light emitting element configured to provide light emission through the passivation film and a light receiving element configured to receive light incident through the passivation film.

  One embodiment of the present invention is a display device including a substrate, a pixel located on the substrate, having a sub-pixel and a sensing element, and a passivation film on the pixel. The sub-pixel has a first light emitting element configured to emit light through the passivation film. The sensing element has a second light emitting element configured to provide light emission through the passivation film and a light receiving element configured to receive light incident through the passivation film.

1 is a schematic perspective view of one display device according to an embodiment of the present invention. 1 is a schematic top view of one display device according to an embodiment of the present invention. 4 is an equivalent circuit of a sub-pixel of a display device according to one embodiment of the present invention. 4 is an equivalent circuit of a sub-pixel of a display device according to one embodiment of the present invention. 4 is an equivalent circuit of a sub-pixel of a display device according to one embodiment of the present invention. 4A and 4B illustrate a method for driving a sub-pixel of a display device according to one embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of one display device according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention can be implemented in various modes without departing from the gist thereof, and is not construed as being limited to the description of the embodiments exemplified below.

  In order to make the explanation clearer, the drawings may be schematically represented with respect to the width, thickness, shape, and the like of each part as compared to the actual embodiment, but are merely examples and limit the interpretation of the present invention. Not what you want. In this specification and each drawing, elements having the same functions as those described with reference to the previous drawings may be denoted by the same reference numerals, and redundant description may be omitted.

  In the present invention, when a plurality of films are formed by processing a certain film, the plurality of films may have different functions and roles. However, the plurality of films are derived from films formed as the same layer in the same process, and have the same layer structure and the same material. Therefore, these plural films are defined as existing in the same layer.

  In the present specification and claims, in expressing a mode of disposing another structure on a certain structure, when simply describing “on top”, unless otherwise specified, It includes both the case where another structure is disposed immediately above and a case where another structure is disposed via another structure above a certain structure.

(First embodiment)
In this embodiment, a structure of a display device 100 which is one embodiment of the present invention will be described with reference to FIGS.

[1. overall structure]
FIG. 1 is a schematic perspective view of the display device 100. As shown in FIG. 1, the display device 100 includes a substrate 102, on which a plurality of pixels 106 and a driving circuit 110 are provided. The pixel 106 and the driver circuit 110 are sealed between the substrate 102 and the counter substrate 104 provided thereon. Although details will be described later, each pixel 106 includes a light-emitting element as a display element, and driving of the light-emitting element is controlled by the drive circuit 110. A wiring (not shown) extends from the pixel 106 to an end portion of the substrate 102, and the wiring is exposed at the end portion to form a terminal 112. A connector (not shown) such as a flexible printed circuit (FPC) board is connected to the terminal 112. Various signals are supplied to the pixel 106 from an external circuit (not shown) via the connector and the drive circuit 110, and thereby an image is reproduced by the pixel 106.

  In FIG. 1, the display device 100 includes two drive circuits 110 so as to sandwich the plurality of pixels 106, but the drive device 110 may be one or may not be provided over the substrate 102. For example, an IC chip manufactured using a semiconductor substrate may be used as a drive circuit, which is installed on the substrate 102 or a connector, and various signals may be supplied from an external circuit to the pixel 106 via the IC chip.

[2. Pixel]
FIG. 2 schematically shows an enlarged top view of the display device 100. As shown in FIG. 2, a plurality of pixels 106 are provided in a matrix on the substrate 102. The display device 100 includes at least two types of pixels (a first pixel 106_1 and a second pixel 106_2).

  A plurality of first pixels 106_1 are provided over the substrate 102, and each of the first pixels 106_1 is provided with a plurality of subpixels 108 that give different colors. The color given by the sub-pixel 108 can be selected so that white display can be realized by one first pixel 106_1. For example, as shown in FIG. 2, the first pixel 106_1 can include three sub-pixels 108R, 108B, and 108G that provide three primary colors of red, blue, and green. The first pixel 106_1 includes four sub-pixels 108, and white display may be realized by these. In this case, one of the four subpixels 108 may be configured to give white. By providing a plurality of first pixels 106_1 having such a structure, full color display can be performed.

  Each subpixel 108 includes a light emitting element (first light emitting element). The color given by each sub-pixel 108 is a color having a different optical characteristic on the sub-pixel 108 by selecting the light-emitting color of the first light-emitting element or providing the first light-emitting element that emits white light on all the sub-pixels 108. It can be controlled by arranging a filter. The former is called a separate coloring method, and the latter is called a white-color filter method. Although any method may be employed for the display device 100, in the following description, an example in which a separate coloring method is employed, and each of the first pixels 106_1 is provided with three subpixels 108R, 108B, and 108G. The explanation will be given.

  At least one second pixel 106_2 is provided over the substrate 102. In the case where a plurality of second pixels 106_2 are provided, the display device 100 may be configured so that the number of the first pixels 106_1 is larger than that of the second pixels 106_2. The second pixel 106_2 is different from the first pixel 106_1 in that it further includes a sensing element 114. The sensing element 114 includes a light emitting element (second light emitting element) and a photodiode as a light receiving element. Due to the presence of the sensing element 114, the subpixel 108 adjacent to the sensing element 114 (subpixel 108G in FIG. 2) is lighter than the other subpixel 108 (subpixels 108R and 108B in FIG. 2). The area of the light emitting region) may be small. The area of the light emitting region will be described later. In the following description, it is assumed that the sub-pixel 108G is adjacent to the sensing element 114.

  The second pixel 106_2 can be configured such that any one of the plurality of sub-pixels 108 and the second light-emitting element of the sensing element 114 emit light in the same color. For example, the light emission colors of the first light-emitting element included in the sub-pixel 108G and the second light-emitting element in the sensing element 114 may be the same. At this time, these light emitting elements may have the same layer structure. These light emitting elements may be configured to emit green light.

  As described later, at least one transistor connected to the first light-emitting element is provided in each of the sub-pixels 108R, 108B, and 108G of the first pixel 106_1 and the second pixel 106_2. Then, based on a switching function of the transistor and a signal sent from the driving circuit 110, gradation of the first light emitting element and timing of light emission are controlled. Thereby, the color and brightness of the entire pixel 106 are adjusted, and an image is reproduced on the display device 100. Accordingly, the sub-pixels 108R, 108B, and 108G included in the first pixel 106_1 and the second pixel 106_2 are video sub-pixels that contribute to video reproduction.

  On the other hand, the photodiode in the sensing element 114 senses light incident from the substrate 102 or the counter substrate 104, and the second light emitting element supplies light necessary for sensing the photodiode. For example, the photodiode is configured to sense light that is emitted from the second light-emitting element and returned after being reflected outside the display device 100. Therefore, the sensing element 114 senses an object existing outside the display device 100 and gives the display device 100 a function as a touch panel.

  Although details will be described later, the emission direction of the first light emitting element provided in the video subpixel (subpixels 108R, 108G, and 108B) is different from the emission direction of the second light emitting element provided in the sensing element 114. It may be the same. For example, the light-emitting element can be configured such that light from the first light-emitting element is extracted from the counter substrate 104 and light from the second light-emitting element is extracted from the substrate 102. Conversely, each light-emitting element may be configured such that light from the first light-emitting element is extracted from the substrate 102 and light from the second light-emitting element is extracted from the counter substrate 104.

  Further, the driving of the first light emitting element may be independent of the driving of the second light emitting element, or may be synchronized with each other. Here, “synchronized” means that the same potential is applied to the light emitting element at the same timing.

  As described above, the first light emitting element can be driven by a transistor. In this case, the display device 100 functions as an active matrix display device. On the other hand, the second light emitting element provided in the sensing element 114 may be driven by a transistor or may be driven without using a transistor. In the latter case, the second light-emitting element can be operated by a driving method similar to that of the passive matrix display device.

[3. Equivalent circuit]
An equivalent circuit of the sub-pixels 108R, 108G, and 108B and the sensing element 114 will be described with reference to FIGS.

  FIG. 3A illustrates an example of an equivalent circuit of the subpixels 108R and 108B. The subpixels 108R and 108B are provided with a scanning line 120, a video signal line 122, a current supply line 124, a transistor 126, a transistor 128, a capacitor 130, a first light emitting element 132, a power supply line 134, and the like. Although not shown, the sub-pixels 108R and 108B may further include transistors, capacitors, wirings, and the like other than those described above.

  The scan line 120 is electrically connected to the gate of the transistor 126 and supplies a signal for controlling on / off of the transistor 126. One terminal of the transistor 126 is electrically connected to the video signal line 122, and the other terminal is electrically connected to the gate of the transistor 128 and one electrode of the capacitor 130. A video signal is supplied to the video signal line 122, and the video signal is supplied from the video signal line 122 to the gate of the transistor 128 through the transistor 126, and the potential is held by the capacitor 130 for a certain period. The current supply line 124 is connected to the other electrode of the capacitor 130 and one terminal of the transistor 128, and the other terminal of the transistor 128 is electrically connected to one electrode (pixel electrode) of the first light-emitting element 132. The The other electrode (counter electrode) of the first light emitting element 132 is electrically connected to the power supply line 134. When a video signal is supplied to the gate of the transistor 128 and the transistor 128 is turned on, current is supplied from the current supply line 124 to the first light-emitting element 132 through the transistor 128, so that the first light-emitting element 132 emits light.

  FIG. 3B illustrates an example of an equivalent circuit of the sub-pixel 108G and the sensing element 114. Since the equivalent circuit of the sub-pixel 108G is the same as that of the sub-pixels 108R and 108B, description thereof is omitted.

  The sensing element 114 includes a current supply line 140, a reference signal line 142, an output signal line 144, a reset signal line 146, a gate signal line 148, a second light emitting element 154, a photodiode 156, transistors 150 and 152, and the like. It is done. The sensing element 114 may be further provided with a transistor, a capacitor, a wiring, and the like.

  The current supply line 140 is connected to one electrode (pixel electrode) of the second light emitting element 154, and the power supply line 134 is connected to the other electrode (counter electrode). Therefore, the second light emitting element 154 can share the power line 134 with the first light emitting element 132. Based on the potential difference applied between the current supply line 140 and the power supply line 134, the second light emitting element 154 emits light. In other words, the second light-emitting element 154 is a so-called passive light-emitting element that is driven without a transistor between the current supply line 140 and the power supply line 134. Note that the other electrode of the second light-emitting element 154 may be connected to a power supply line different from the power supply line 134 of the sub-pixels 108R, 108G, and 108B.

  One electrode of the photodiode 156 is electrically connected to the reset signal line 146, and the other electrode is electrically connected to the gate of the transistor 150. One terminal of the transistor 150 is electrically connected to the reference signal line 142, and the other terminal is electrically connected to one terminal of the transistor 152. The gate of the transistor 152 is electrically connected to the gate signal line 148 and the other terminal is electrically connected to the output signal line 144.

  The sensing element 114 can have an equivalent circuit different from the equivalent circuit illustrated in FIG. An example is shown in FIG. In FIG. 4, the equivalent circuit of the sub-pixel 108G is the same as that of FIG. 3B, and the photodiode 156, the transistors 150 and 152, the reference signal line 142 connected to them, the output signal line 144, and the reset signal. Since the connection relationship of the line 146, the gate signal line 148, and the like is also the same, the description is omitted. Similar to the equivalent circuit in FIG. 3B, the sub-pixel 108G can include transistors, capacitors, and wirings other than the transistor 126 and the capacitor 130 illustrated.

  The equivalent circuit illustrated in FIG. 4 is different from that illustrated in FIG. 3B in that the second light-emitting element 154 is driven through a transistor. Therefore, the second light-emitting element 154 is a so-called active light-emitting element.

  Specifically, the sensing element 114 includes a scanning line 160, a signal line 162, transistors 164 and 166, a capacitor element 168, and a second light emitting element 154. The scan line 160 is electrically connected to the gate of the transistor 164 and supplies a signal for controlling on / off of the transistor 164. One terminal of the transistor 164 is electrically connected to the signal line 162, and the other terminal is electrically connected to the gate of the transistor 166 and one electrode of the capacitor 168. A signal for controlling the second light-emitting element 154 is supplied to the signal line 162, and this signal is supplied to the gate of the transistor 166 through the transistor 164, and the potential is held by the capacitor 168 for a certain period. . The current supply line 124 is connected to the other electrode of the capacitor 168 and one terminal of the transistor 166, and the other terminal of the transistor 166 is electrically connected to one electrode (pixel electrode) of the second light-emitting element 154. The The other electrode (counter electrode) of the second light-emitting element 154 is electrically connected to the power supply line 134. Therefore, the current supply line 124 and the power supply line 134 are shared by the sub-pixel 108G and the sensing element 114. However, the sub-pixel 108G and the sensing element 114 may each independently have a current supply line. When a signal is supplied to the gate of the transistor 166 and the transistor 166 is turned on, current is supplied from the current supply line 124 to the second light-emitting element 154 through the transistor 166, so that the second light-emitting element 154 emits light.

  As described above, the driving of the second light emitting element may be synchronized with the driving of the first light emitting element. An equivalent circuit in this case is shown in FIG. The equivalent circuit shown in FIG. 5 is different from the equivalent circuit of FIG. 3B in that the first light-emitting element 132 and the second light-emitting element 154 are connected in parallel between the transistor 128 and the power supply line 134. Different. Specifically, one electrode of the second light-emitting element 154 is connected to the other electrode of the transistor 128. With this configuration, the pixel electrode of the first light-emitting element 132 and the pixel electrode of the second light-emitting element 154 are electrically connected, and these elements can emit light at the same timing.

[4. Photodiode Operation]
The operation of the photodiode 156 of the sensing element 114 having the equivalent circuit shown in FIG. 3B will be described with reference to FIG.

  First, in the state where the potential of the output signal line 144 is set to H (High) and precharge is completed in advance, the potential of the reset signal line 146 is set to H (High) at time A, and a forward bias is applied to the photodiode 156. Apply. As a result, the photodiode 156 becomes conductive, and the gate potential of the transistor 150 becomes H.

  Next, at time B, the potential of the reset signal line 146 is changed to L (Low), and the accumulation period is started. In the accumulation period, the gate potential of the transistor 150 starts to decrease due to the off-state current of the photodiode 156. Since the photodiode 156 receives light to increase off-state current, the gate potential drop of the transistor 150 becomes faster as the amount of received light increases.

  Next, at time C, the potential of the gate signal line 148 is changed to H. This starts the selection period. By this change, the transistor 152 is turned on, and the reference signal line 142 and the output signal line 144 become conductive through the transistors 150 and 152, and accordingly, the potential of the output signal line 144 starts to decrease. The speed of this potential drop is determined by the current between the terminals of the transistor 150 (source-drain current), which is determined by the gate voltage of the transistor 150. That is, the speed of the potential drop is determined by the amount of light received by the photodiode 156.

  At time D, the potential of the gate signal line 148 is changed to L. Accordingly, the gate of the transistor 152 is in a floating state, and the potential of the output signal line 144 is constant. At this time, the potential of the output signal line 144 is determined by the amount of light received by the photodiode 156. Therefore, by measuring the potential of the output signal line 144, the amount of light received by the photodiode 156 can be estimated.

[5. Cross-sectional structure]
FIG. 7 schematically shows a cross-sectional structure of the display device 100. FIG. 7 shows a part of the sub-pixels 108G and 108B and the sensing element 114.

  The display device 100 includes a transistor 128 and a photodiode 156 over a substrate 102. As an optional structure, an undercoat 180 may be provided between the substrate 102, the transistor 128, and the photodiode 156. The undercoat 180 has a function of preventing impurities such as metal ions from diffusing from the substrate 102 and preventing the transistor 128 and the photodiode 156 from being contaminated.

  The transistor 128 includes a semiconductor film 182, a gate insulating film 184, a gate 186, and terminals 192 and 194. Although the transistor 128 illustrated in FIG. 7 is a top-gate transistor, the structure of the transistor 128 is not limited. For example, the transistor 128 may be a bottom gate type, and the vertical relationship between the terminals 192 and 194 and the semiconductor film 182 is not limited.

  The display device 100 can include an interlayer film 188 as an arbitrary configuration. The interlayer film 188 functions as a protective film for the transistors 126, 128, 150, 152 and the photodiode 156. As shown in FIG. 7, a first planarization film 190 is provided so as to cover the transistor 128 and the photodiode 156, so that unevenness caused by the transistor 128 and the photodiode 156 is absorbed and a flat top surface is obtained. Can be given. The terminals 192 and 194 are provided over the first planarization film 190 and are electrically connected to the semiconductor film 182 in openings provided in the first planarization film 190, the interlayer film 188, and the gate insulating film 184.

  The photodiode 156 includes a semiconductor film 200 and a pair of electrodes 202 and 204. The semiconductor film 200 includes a p-type semiconductor film 200p, an n-type semiconductor film 200n, and an i-type semiconductor film 200i sandwiched therebetween. The p-type semiconductor film 200p contains impurities that can impart p-type conductivity, such as boron ions. The n-type semiconductor film 200n contains impurities that can impart n-type conductivity, such as phosphorus or arsenic ions. The i-type semiconductor film 200i does not contain the impurities described above, or the concentration thereof is lower than that of the p-type semiconductor film 200p and the n-type semiconductor film 200n. The i-type semiconductor film 200i may contain an impurity capable of imparting p-type conductivity at a lower concentration than the p-type semiconductor film 200p. The photodiode 156 receives light at the i-type semiconductor film 200i, and the amount of received light is estimated according to the driving method described above.

  In FIG. 7, the i-type semiconductor film 200i is provided on the p-type semiconductor film 200p and the n-type semiconductor film 200n so as to cover a part of them, but the i-type semiconductor film 200i and the p-type semiconductor film 200p are provided. The n-type semiconductor film 200n may exist in the same layer. In this case, the upper surfaces of the i-type semiconductor film 200i, the p-type semiconductor film 200p, and the n-type semiconductor film 200n are on the same plane. Alternatively, the i-type semiconductor film 200i, the p-type semiconductor film 200p, and the n-type semiconductor film 200n may be stacked on each other. A structure in which these semiconductor films are stacked will be described in a ninth embodiment.

  The first planarization film 190 covers the semiconductor film 200. The electrodes 202 and 204 are provided on the first planarization film 190, and the p-type semiconductor film 200p and the n-type semiconductor film are provided in openings provided in the first planarization film 190, the interlayer film 188, and the gate insulating film 184, respectively. 200n is electrically connected. As an arbitrary structure, the light-shielding film 206 can be provided over the photodiode 156 in the display device 100 so as to overlap the i-type semiconductor film 200i. Accordingly, light incident from the counter substrate 104 side can be blocked. The light shielding film 206 may be electrically floating.

  As shown in FIG. 7, the current supply line 140 can be provided on the first planarization film 190. In this case, the current supply line 140 and the light shielding film 206 can exist in the same layer. The current supply line 140 may be provided between the interlayer film 188 and the first planarization film 190 or on a second planarization film 196 described later.

  The display device 100 may include a second planarization film 196 over the terminals 192 and 194, the current supply line 140, the electrodes 202 and 204, and the light shielding film 206. The second planarization film 196 has a function of absorbing unevenness caused by various elements provided below and providing a flat upper surface.

  The pixel electrodes 210 and 230 of the first light emitting element 132 and the second light emitting element 154 are provided on the second planarization film 196. These are electrically connected to the terminal 194 and the current supply line 140 in the opening provided in the second planarization film 196, respectively. Accordingly, the pixel electrode 210 is electrically connected to the transistor 128.

  Here, the pixel electrode 210 of the sub-pixel 108G can be configured to function as a reflective electrode that reflects visible light. Accordingly, light obtained from the light-emitting layer 216 in the first light-emitting element 132 is reflected by the pixel electrode 210 and can be extracted through the counter electrode 220 and the counter substrate 104 as indicated by an arrow 234 in the drawing. On the other hand, the pixel electrode 230 of the second light-emitting element 154 can be configured to function as a light-transmitting electrode that transmits visible light. Thus, light obtained from the light-emitting layer 216 in the second light-emitting element 154 passes through the pixel electrode 230 and can be extracted through the substrate 102 as indicated by an arrow 236 in the drawing. That is, in the sub-pixel 108G and the sensing element 114, the light emission directions can be reversed.

  In FIG. 7, each of the pixel electrodes 210 and 230 is drawn to have a single layer structure, but these may be formed of a plurality of layers. For example, as illustrated in FIG. 8A, the pixel electrode 210 includes a first layer 210_1 that can reflect visible light and a second layer 210_2 that can transmit visible light over the first layer 210_1. You may do it. The first layer 210_1 can contain, for example, a metal such as titanium, aluminum, silver, or magnesium, or an alloy containing these metals. The first layer 210_1 not only imparts high light reflectivity to the pixel electrode 210 but also the terminal 194 and the pixel electrode. It is possible to prevent deterioration of electrical contact with 210. The first layer 210_1 may have a stacked structure of the above metals, and may include a stacked structure of titanium and aluminum, for example. On the other hand, the second layer 210_2 can include a conductive oxide capable of transmitting visible light, such as indium-tin oxide (ITO) or indium-zinc oxide (IZO). By using a conductive oxide, a carrier injection barrier to the EL layer 212 provided over the pixel electrode 210 can be reduced.

  On the other hand, in the second light-emitting element 154, the pixel electrode 230 can be formed using a conductive oxide. Alternatively, a film containing a metal such as silver, magnesium, aluminum, platinum, palladium, gold, nickel iridium, chromium, or an alloy thereof is formed with a thickness that allows visible light to be transmitted (2 nm to 30 nm, or 3 nm to 20 nm). The pixel electrode 230 may be configured. Alternatively, as shown in FIG. 8B, a first layer 230_1 containing a metal is provided so as to cover the opening of the second planarization film 196, and the second layer is electrically connected to the first layer 230_1. A second layer 230_2 containing a conductive oxide may be provided so as to be in contact with the planarization film 196. The first layer 230_1 may have a structure similar to that of the first layer 210_1 of the pixel electrode 210. Thereby, it is possible to prevent the electrical contact between the current supply line 140 and the pixel electrode 230 from deteriorating and reduce the carrier injection barrier to the EL layer 212.

  A partition wall 198 is provided on the pixel electrodes 210 and 230 and the second planarization film 196 (FIG. 7). The partition wall 198 covers the end portions of the pixel electrodes 210 and 230, thereby absorbing irregularities caused by these. The partition wall 198 is an insulating film, and the pixel electrodes 210 and 230 are exposed in the opening.

  An EL layer 212 is provided so as to cover the pixel electrodes 210 and 230 and the partition wall 198, and a counter electrode 220 is further provided on the EL 212. The EL layer 212 can be composed of a plurality of layers. For example, a carrier injection layer, a carrier transport layer, a light emitting layer, a carrier blocking layer, an exciton blocking layer, and the like can be appropriately selected and combined. FIG. 7 shows a structure in which a carrier injection / transport layer 214, a light-emitting layer 216, and a carrier injection / transport layer 218 are sequentially stacked as representative layers in the first light-emitting element 132 and the second light-emitting element 154. ing.

  Carriers are injected from the pixel electrodes 210 and 230 and the counter electrode 220 into the EL layer 212, and recombination of carriers occurs in the light emitting layer 216, resulting in light emission. Therefore, light emission occurs in a region where the EL layer 212 is in contact with both the pixel electrodes 210 and 230 and the counter electrode 220. That is, the light emitting region of the first light emitting element 132 is a region where the pixel electrode 210 is exposed from the partition 198. Similarly, the light emitting region of the second light emitting element 154 is a region where the pixel electrode 230 is exposed from the partition 198. As described above, the light-emitting area of the sub-pixel adjacent to the sensing element 114 (sub-pixel 108G in FIG. 7) can be larger than the light-emitting area of the sensing element 114.

  As shown in FIG. 7, subpixels 108 (subpixels 108 </ b> G and 108 </ b> B in FIG. 7) adjacent to each other can have different light emitting layers 216 and 217. As a result, different emission colors can be obtained between adjacent sub-pixels 108. On the other hand, the first light emitting element 132 of the sub-pixel 108G and the second light emitting element 154 of the sensing element 114 may have the same structure. Even when the structures of the first light emitting element 132 and the second light emitting element 154 are different from each other, for example, one light emitting layer 216 can be shared as shown in FIG. In this case, the light emitting layer 216 is formed over the sensing element 114 from the sub-pixel 108G via the partition 198. In the case where the first light-emitting element 132 and the second light-emitting element 154 have the same light-emitting layer 216, the same light emission color can be obtained.

  The counter electrode 220 can be formed so as to be shared by the first light emitting element 132 and the second light emitting element 154. The counter electrode 220 can be a film containing a conductive oxide or a film containing a metal that can be used for the pixel electrodes 210 and 230 and having a thickness that allows visible light to pass therethrough. In order to selectively extract light emitted from the second light-emitting element 154 through the substrate 102, the reflective electrode 232 may be provided between the EL layer 212 and the counter electrode 220 or on the counter electrode 220. The reflective electrode 232 can include a metal such as aluminum or silver.

  The display device 100 can include a passivation film 240 on the counter electrode 220 as an arbitrary configuration. The passivation film 240 has a function of preventing impurities such as water and oxygen from entering the first light-emitting element 132 and the second light-emitting element 154 from the outside. As shown in FIG. 7, the passivation film 240 can be formed as a multilayer film including, for example, a first layer 242, a second layer 244, and a third layer 246. The first layer 242 and the third layer 246 can contain an inorganic compound containing silicon. On the other hand, the second layer 244 can include an organic compound such as an epoxy resin or an acrylic resin.

  In the display device 100, the counter substrate 104 is further provided over the first light emitting element 132 and the second light emitting element 154 with an adhesive layer 250 interposed therebetween. The counter substrate 104 can include a material similar to that of the substrate 102.

  As described above, light emitted from the sub-pixels 108G and 108B is extracted through the counter substrate 104, whereas light emitted from the sensing element 114 is extracted through the substrate 102. The former light emission contributes to the provision of images. The latter light is incident on the i-type semiconductor film 200 i of the photodiode 156 when returning to the display device 100 after being reflected by the object 238 outside the display device 100. As described above, the photodiode 156 of the display device 100 can estimate the amount of received light. For this reason, the display device 100 can reproduce an image on one surface and can sense the presence and movement of an external object 238 on the other surface, and can function as a display device equipped with a touch panel. it can.

  Since the detection of the object by the photodiode 156 is performed by light, the object 238 can be detected regardless of the presence or absence of physical contact between the display device 100 and the object 238. For this reason, for example, biological information can be taken in by bringing the substrate 102 of the display device 100 close to or in contact with the skin or the like. For example, since information related to fingerprints, palm prints, veins, and the like possessed by individual living bodies can be acquired, the display device 100 can be used as a biometric authentication device. In particular, when the display device 100 is manufactured using a flexible substrate as the substrate 102 or the counter substrate 104, the display device 100 can be used as a wearable device, and various dynamic information (for example, pulses) included in a living body can be used. Waves etc.) can be monitored at any time. For example, if the display device 100 is worn on a wrist or the like as a wearable device, a device for causing one surface of the display device 100 to function as a wristwatch that displays an image and simultaneously acquiring biological information such as a pulse wave on the other surface. Can function as. In this case, the light emitted from the second light emitting element 154 is absorbed by the blood vessel in the living body, and the change in the amount of absorption accompanying the change in the volume of the blood vessel is measured by the photodiode 156.

  Furthermore, in the display device 100 shown in this embodiment, as described later, the subpixels 108R, 108B, and 108G and the sensing element 114 can be manufactured in a series of steps. For example, in the display device 100 illustrated in FIG. 7, the transistor 128 that controls the first light-emitting element 132 and the photodiode 156 provided in the sensing element 114 can be manufactured through a series of steps. In addition, the first light-emitting element 132 and the second light-emitting element 154 can be formed at the same time. Therefore, the number of components can be greatly reduced, and a display device having a function of reproducing video and a function of acquiring biological information can be manufactured at low cost.

(Second Embodiment)
In this embodiment, a method for manufacturing the display device 100 will be described with reference to FIGS. In the present embodiment, the display device 100 is described as a flexible display device. 9 to 18 are schematic cross-sectional views of the display device 100 corresponding to FIG. A description of the same configuration as in the first embodiment may be omitted.

[1. Transistor, Photodiode]
As shown in FIG. 9A, a base film 172 is formed over the support substrate 170. The support substrate 170 supports elements such as the transistors 126 and 128, the photodiode 156, the first light-emitting element 132, and the second light-emitting element 154. Therefore, it is only necessary to have heat resistance to the process temperature for forming these elements and chemical stability to the chemicals used in the process. Specifically, the support substrate 170 can include glass, quartz, ceramic, or metal. The support substrate 170 does not necessarily have flexibility, and may have a hardness that does not substantially curve. In the case where the display device 100 is not flexible, the support substrate 170 functions as the substrate 102 and thus preferably contains glass or quartz that can transmit visible light.

  The base film 172 functions as a flexible substrate, for example, using polyimide, polyamide, polycarbonate, etc., and applying a wet film formation method such as an inkjet method, a spin coating method, a dip coating method, or a laminating method. Can be produced.

  Next, as shown in FIG. 9A, an undercoat 180 is formed on the base film 172. The undercoat 180 is a film having a function of preventing impurities such as alkali metals from diffusing from the support substrate 170 and the base film 172 to the transistors 126, 128, 150, 152, the photodiode 156, and the like. Inorganic insulators such as silicon nitride oxide and silicon oxynitride can be included. The undercoat 180 can be formed to have a single layer or a laminated structure by applying a chemical vapor deposition method (CVD method), a sputtering method, or the like. When the impurity concentration in the base film 172 is low, the undercoat 180 may not be provided or may be formed so as to cover only a part of the base film 172.

  Next, semiconductor films 182 and 200 are formed (FIG. 9B). The former constitutes the active layer of the transistor 128, and the latter is included in the photodiode 156. At this stage, the semiconductor film 200 that provides the p-type semiconductor film 200p and the n-type semiconductor film 200n among the semiconductor films 200 included in the photodiode 156 is formed. The semiconductor films 182 and 200 can include a group 14 element such as silicon. Although the semiconductor films 182 and 200 may include an oxide semiconductor, the semiconductor film 200 preferably includes a group 14 element in consideration of absorbability with respect to visible light. As the oxide semiconductor, a Group 13 element such as indium or gallium can be included. For example, a mixed oxide (IGO) of indium and gallium can be given. The oxide semiconductor may further include a Group 12 element. An example thereof is a mixed oxide (IGZO) containing indium, gallium, and zinc. The crystallinity of the semiconductor films 182 and 200 is not limited, and may be single crystal, polycrystal, microcrystal, or amorphous. These morphologies may be mixed in the semiconductor films 182 and 200.

  In the case where the semiconductor films 182 and 200 include silicon, the semiconductor films 182 and 200 may be formed by a CVD method using silane gas or the like as a raw material. The resulting amorphous silicon may be crystallized by heat treatment or irradiation with light such as a laser. In the case where the semiconductor films 182 and 200 include an oxide semiconductor, the semiconductor films 182 and 200 can be formed by a sputtering method or the like.

  Next, a resist mask 174 is formed so as to cover one of the semiconductor film 182 and the semiconductor film 200. After that, an impurity imparting p-type conductivity such as boron ions is added to the semiconductor film 200 by an ion implantation method or a doping method, so that the p-type semiconductor film 200p is formed (FIG. 9C).

  Subsequently, the resist mask 174 is removed, and a resist mask 176 that covers the semiconductor film 182 and the p-type semiconductor film 200p is formed (FIG. 10A). An impurity imparting n-type conductivity, such as phosphorus or arsenic ions, is added to the exposed semiconductor film 200 to form an n-type semiconductor film 200n (FIG. 10B).

  After removing the resist mask 176, an i-type semiconductor film 200i is formed so as to cover part of the p-type semiconductor film 200p and the n-type semiconductor film 200n by using a CVD method, a sputtering method, or the like (FIG. 10B). . Subsequently, a gate insulating film 184 that covers the semiconductor films 182 and 200 is formed. The gate insulating film 184 may have either a single layer structure or a stacked structure, and can be formed by a method similar to that for the undercoat 180.

  Next, as illustrated in FIG. 10C, a gate 186 is formed over the gate insulating film 184 by a sputtering method or a CVD method. The gate 186 can be formed to have a single layer or a stacked structure using a metal such as titanium, aluminum, copper, molybdenum, tungsten, or tantalum or an alloy thereof. For example, a structure in which a metal having a relatively high melting point such as titanium, tungsten, or molybdenum and a metal having high conductivity such as aluminum or copper is sandwiched can be employed. When the sub-pixel 108 has the equivalent circuit shown in FIGS. 3A and 3B, the gate 186 can be formed simultaneously with the video signal line 122 and the current supply line 124. Therefore, the gate 186 can be in the same layer as the video signal line 122 and the current supply line 124. Although not illustrated, the source region and the drain region may be formed by doping the semiconductor film 182 using the gate 186 as a mask.

  Next, an interlayer film 188 and a first planarization film 190 are formed over the gate 186 (FIG. 11A). The interlayer film 188 may have a single-layer structure or a stacked structure, and can be formed by a method similar to that for the undercoat 180. The first planarization film 190 can be formed of an organic insulator. Examples of the organic insulator include polymer materials such as an epoxy resin, an acrylic resin, polyimide, polyamide, polyester, polycarbonate, and polysiloxane, which can be formed by the wet film forming method described above.

  Next, the interlayer film 188, the first planarization film 190, and the gate insulating film 184 are etched to form openings that expose the semiconductor films 182 and 200 (FIG. 11B). The opening can be formed, for example, by performing plasma etching in a gas containing fluorine-containing hydrocarbon. After that, a metal film is formed so as to cover the opening using a sputtering method or a CVD method, and then the metal film is processed by etching, so that the terminal 192 of the transistor 128 is formed over the first planarization film 190. 194, electrodes 202 and 204 of the photodiode 156 are formed. The metal film can have a structure similar to that of the gate 186. At this time, the light shielding film 206 and the current supply line 140 may be formed at the same time (FIG. 12A).

  Through the above process, the transistor 128 and the photodiode 156 are formed. As described above, the transistor 128 and the photodiode 156 can be formed through a series of steps.

[2. Light emitting element]
Subsequently, a second planarization film 196 is formed over the terminals 192 and 194 and the electrodes 202 and 204 (FIG. 12A). The second planarization film 196 can be formed by a method similar to that for the first planarization film 190.

  After that, the second planarization film 196 is etched to expose the terminals 194 and the current supply line 140 (FIG. 12B). Etching may be performed by a method similar to that for etching the first planarization film 190.

  Subsequently, the pixel electrodes 210 and 230 of the first light-emitting element 132 and the second light-emitting element 154 are formed to be connected to the terminal 194 and the current supply line 140, respectively (FIG. 13A). In the case where the pixel electrodes 210 and 230 have a two-layer structure as illustrated in FIGS. 8A and 8B, the first layers 210_1 and 230_1 are formed using silver, aluminum, magnesium, titanium, or an alloy thereof. The second layers 210_2 and 230_2 may be formed by CVD, sputtering, vapor deposition, or the like, and then sputtering ITO or IZO.

  Next, a partition 198 is formed so as to cover the end portions of the pixel electrodes 210 and 230 (FIG. 13A). The partition wall 198 can electrically insulate the pixel electrodes 210 of the adjacent first light emitting elements 132 or the pixel electrodes 210 and the pixel electrodes 230 of the second light emitting elements 154 from each other. The partition wall 198 can be formed by a wet film formation method using an epoxy resin, an acrylic resin, or the like.

  Next, the first light-emitting element 132, the EL layer 212 of the second light-emitting element 154, and the counter electrode 220 are formed. Here, the carrier injection / transport layer 214 is shared by the first light-emitting element 132 of the sub-pixels 108G and 108B and the second light-emitting element 154 of the sensing element 114, so that (FIG. 13B). As the carrier injection / transport layer 214, a material having a high hole injection property and a high transport property can be used. The carrier injection / transport layer 214 may have a single layer structure or a stacked structure. The carrier injection / transport layer 214 may be formed by a wet method, a vapor deposition method, or the like.

  After that, the light emitting layer 216 is formed so as to overlap the pixel electrode 210 of the subpixel 108G, the pixel electrode 230 of the second light emitting element 154, and the partition wall 198 existing in the region between the subpixel 108G and the second light emitting element 154. It is formed on the carrier injection / transport layer 214 (FIG. 14A). Accordingly, the first light-emitting element 132 and the second light-emitting element 154 of the sub-pixel 108G share the same light-emitting layer 216 and can emit light with the same color. The emission color is, for example, green.

  On the other hand, in the sub-pixel 108B, a light-emitting layer 217 containing a material different from that of the light-emitting layer 216 can be formed over the carrier injection / transport layer 214 (FIG. 14A). Thereby, the sub-pixels 108G and 108B can give different colors to each other. The color of light provided by the sub-pixel 108B is, for example, blue. Thus, in order to give different colors to the adjacent subpixels 108B and 108B, the light emitting layers 216 and 217 may be formed by vapor deposition while shielding one of the subpixels 108 using a metal mask. . Alternatively, a solution or a suspension of a material included in the light-emitting layers 216 and 217 may be discharged to the target subpixel 108 using an inkjet method.

  After that, a carrier injection / transport layer 218 is formed over the light emitting layers 216 and 217 by a wet method or a vapor deposition method (FIG. 14B). The carrier injection / transport layer 218 can include a material having a high electron injection property and a high transport property, and can have a single-layer structure or a stacked structure. As shown in FIG. 14B, the carrier injection / transport layer 218 may also be shared by the first light-emitting element 132 and the second light-emitting element 154 of the subpixels 108B and 108G.

  Subsequently, the counter electrode 220 is formed (FIG. 14B). The counter electrode 220 is transmissive to visible light and may include a conductive oxide having transparency such as ITO or IZO. In this case, the counter electrode 220 can be formed by a sputtering method. Alternatively, the counter electrode 220 may be formed by vapor-depositing a metal such as aluminum, silver, magnesium, platinum, palladium, gold, nickel, iridium, or chromium so as to transmit visible light. Accordingly, light emitted from the first light emitting element 132 can be extracted through the counter electrode 220.

  On the other hand, since the second light-emitting element 154 is configured to extract light emitted through the pixel electrode 230, the reflective electrode 232 is formed over the counter electrode 220 (FIG. 15A). For the reflective electrode 232, a metal having high reflectivity with respect to visible light can be used. Examples of the metal include aluminum and silver. As shown in FIG. 15A, the reflective electrode 232 and the counter electrode 220 can be in physical and electrical contact with each other; however, another conductive film or the like is provided between the reflective electrode 232 and the counter electrode 220. May be provided. Although not shown, the reflective electrode 232 may be formed before the counter electrode 220 so that the reflective electrode 232 is covered with the counter electrode 220.

  Through the above steps, the first light-emitting element 132 and the second light-emitting element 154 are formed by the same process.

[3. Passivation film]
Thereafter, a passivation film 240 may be formed. For example, as shown in FIG. 15B, first, the first layer 242 is formed over the counter electrode 220 and the reflective electrode 232. The first layer 242 can include an inorganic material such as silicon nitride, silicon oxide, silicon nitride oxide, or silicon oxynitride, and can be formed by a method similar to that for the undercoat 180.

  Subsequently, the second layer 244 is formed. The second layer 244 can include an organic resin including an acrylic resin, an epoxy resin, polysiloxane, polyimide, polyester, or the like. Further, as shown in FIG. 15B, the second layer 244 may be formed with a thickness so as to absorb unevenness caused by the partition wall 198 and to provide a flat surface. The second layer can also be formed by a wet film formation method, but the oligomer that is the raw material of the polymer material is made into a mist or gas under reduced pressure, and this is sprayed onto the first layer 242 and then the oligomer. You may form by superposing | polymerizing.

  After that, a third layer 246 is formed (FIG. 15B). The third layer 246 has a structure similar to that of the first layer 242 and can be formed by a similar method. By forming the passivation film 240, impurities can be prevented from entering the display device 100, and the reliability of the first light-emitting element 132 and the second light-emitting element 154 can be improved.

  Through the above steps, the passivation film 240 is formed.

[4. Peeling process]
Next, a peeling process is performed, and the supporting substrate 170 is peeled from the base film 172 to impart flexibility to the display device 100. Specifically, as shown in FIG. 16, the counter substrate 104 is bonded onto the passivation film 240 via an adhesive layer 250. At this time, a flexible substrate containing a polymer material such as polyimide, polyester, or polysiloxane is used as the counter substrate 104. In the case where flexibility is not given to the display device 100, the display device 100 can be obtained by providing a glass substrate or a quartz substrate as the counter substrate 104. The counter substrate 104 may have a touch panel function. Further, a structure in which the counter substrate 104 is not provided may be employed. In the case where the counter substrate 104 is not provided, a protective film formed of a circularly polarizing plate or a resin may be provided on the passivation film 240.

  After providing the counter substrate 104, the support substrate 170 is peeled from the base film 172. Specifically, for example, light such as a laser is irradiated from the support substrate 170 side to reduce the adhesion between the support substrate 170 and the base film 172 (FIG. 16). If necessary, light irradiation may be performed while the photodiode 156 is shielded from light. Thereafter, using a physical force, the support substrate 170 is peeled from the base film 172 at the interface between the support substrate 170 and the base film 172 where the adhesive force is reduced (FIG. 17). Due to the flexibility of the base film 172 and the counter substrate 104, the obtained display device 100 can also have flexibility, and the flexible display device 100 is obtained. Note that, if necessary, the display device 100 may be reinforced by separately bonding a second substrate 252 under the base film 172 (FIG. 18). The second substrate 252 is a flexible resin substrate, and is formed of, for example, polyimide, polyamide, or polycarbonate. The counter substrate 104 may have a touch panel function.

  Through the above process, the flexible display device 100 can be manufactured. Due to the flexibility of the display device 100, the display device 100 can be used as a wearable device.

(Third embodiment)
In the present embodiment, a display device 300 having a structure different from those in the first and second embodiments will be described with reference to FIG. The description of the same configuration as the first and second embodiments may be omitted.

  In the display device 300 illustrated in FIG. 19, the counter electrode 220 is not shared by the first light emitting element 132 and the second light emitting element 154, and the reflective electrode 232 is in direct contact with the EL layer 212 in the sensing element 114. Is different from the display device 100 in that Accordingly, the counter electrode 220 does not overlap the pixel electrode 230 in the light emitting region of the second light emitting element 154. Further, the first layer 242 of the passivation film 240 may be in contact with the EL layer 212 between the counter electrode 220 and the reflective electrode 232. Although not shown, the counter electrode 220 and the reflective electrode 232 may be electrically connected so that the same potential is applied.

  In the display device 100, a light-transmitting pixel electrode 230 is included between the EL layer 212 and the reflective electrode 232. Therefore, in the second light emitting element 154, the optical path length of the light emitted from the light emitting layer 216 and reflected and extracted by the reflective electrode 232 is emitted from the light emitting layer 216 of the first light emitting element 132 and is output from the pixel electrode 230. It becomes larger than the optical path length of the light extracted by reflection. This difference is particularly noticeable when the reflective surface of the first light emitting element 132 is the interface between the EL layer 212 and the pixel electrode 210. Therefore, there is a difference in the light interference effect between the first light-emitting element 132 and the second light-emitting element 154, which may cause a large difference in emission color.

  On the other hand, in the display device 300, the optical path length of the second light emitting element 154 can be adjusted to be substantially the same as the optical path length of the first light emitting element 132. Thus, the first light-emitting element 132 and the second light-emitting element 154 can emit light.

(Fourth embodiment)
In this embodiment, a display device 310 having a structure different from those in the first to third embodiments will be described with reference to FIG. The description of the same configuration as in the first to third embodiments may be omitted.

  The display device 310 is different from the display devices 100 and 300 in that the reflective electrode 232 is not provided in the second light emitting element 154 and the light emitted from the second light emitting element 154 is reflected to the substrate 102 side. The reflective film 260 is provided on the second light emitting element 154 so as to be separated from the second light emitting element 154. As a result, as indicated by an arrow 236, the light emitted from the light emitting layer 216 of the second light emitting element 154 passes through the counter electrode 220, is reflected by the reflective film 260, and then passes through the second light emitting element 154. Then, it is taken out through the substrate 102. As shown in FIG. 20, the reflective film 260 may be provided in contact with the counter substrate 104, or may be provided in contact with the third layer 246 of the passivation film 240. Therefore, the reflective film 260 may be electrically independent from the counter electrode 220. In the case where the reflective film 260 is provided so as to be in contact with the counter substrate 104, the reflective film 260 can also be formed by screen printing.

  Since the display device 310 does not require precise alignment of the metal mask when the reflective electrode 232 is formed by vapor deposition, the display device can be manufactured more easily and at low cost.

(Fifth embodiment)
In this embodiment, a display device 320 having a structure different from those of the first to fourth embodiments will be described with reference to FIG. The description of the same configuration as in the first to fourth embodiments may be omitted.

  The display device 320 is different from the display device 100 in that the second light emitting element 154 is driven by the transistor 166. Therefore, the display device 320 can reproduce a high-definition image even when the second light-emitting element 154 is used.

(Sixth embodiment)
In the present embodiment, a display device 330 having a structure different from those in the first to fifth embodiments will be described with reference to FIG. The description of the same configuration as in the first to fifth embodiments may be omitted.

  The display device 330 shown in FIG. 22 has the structure in which the passivation film 240 is not provided in the structure in which the counter substrate 104 is not provided in that light emitted from the second light emitting element 154 is extracted not only from the substrate 102 but also from the counter substrate 104. It differs from the display device 320 in that it is also taken out from the side. Therefore, it is not necessary to install the reflective electrode 232 and the light shielding film 206 of the display device 320. Therefore, as indicated by an arrow 235, the light emitted from the second light emitting element 154 through the counter substrate 104 and reflected by the external object 238 can be detected by the photodiode 156. Therefore, a function as a touch panel can be provided not only on the substrate 102 side but also on the counter substrate 104 side, and the use as a wearable device can be expanded. Note that a structure in which both the light indicated by the arrow 235 and the light indicated by the arrow 236 are extracted from the second light-emitting element 154 may be employed, or a structure in which only the light indicated by the arrow 235 is extracted from the second light-emitting element 154 may be employed.

(Seventh embodiment)
In this embodiment, a display device 340 having a structure different from those of the first to sixth embodiments will be described with reference to FIG. The description of the same configuration as in the first to sixth embodiments may be omitted.

  The display device 340 is different from the display devices 100, 300, 310, 320, and 330 in that the first light emitting element 132 and the second light emitting element 154 emit light in synchronization. Specifically, the pixel electrode 230 of the second light-emitting element 154 is electrically connected to the terminal 194 of the transistor 128, and the same voltage is applied at the same timing as the pixel electrode 210. Therefore, the display on the substrate 102 side can be easily confirmed on the counter substrate 104 side.

(Eighth embodiment)
In this embodiment, a display device 350 having a structure different from those of the first to seventh embodiments will be described with reference to FIG. The description of the same configuration as in the first to seventh embodiments may be omitted.

  The display device 350 is a display device 100, 300, 310, 320 in that light emitted from the first light emitting element 132 is extracted through the substrate 102 and light emitted from the second light emitting element 154 is extracted through the counter substrate 104. , 330 and 340. Accordingly, the pixel electrode 210 is configured to transmit visible light, while the pixel electrode 230 is configured to reflect visible light. On the other hand, a reflective electrode 232 capable of reflecting visible light is provided on the EL layer 212 of the first light-emitting element 132 via a counter electrode 220 capable of transmitting visible light. The counter electrode 220 is disposed over the EL layer 212 of the second light-emitting element 154, but the reflective electrode 232 is not provided. Although not illustrated, in the subpixels 108B and 108G, the reflective electrode 232 may be in contact with the EL layer 212, and the counter electrode 220 may be provided thereover.

  The light shielding film 206 may not be provided on the photodiode 156. On the other hand, a light shielding film 206 may be provided under the photodiode 156. The light shielding film 206 may be provided so as to be in contact with the substrate 102 as shown in FIG. 24, or the undercoat 180 may be formed of a plurality of layers, and may be provided between these layers. In the display device 350, the light shielding film 206 is formed in a process different from the terminals 192 and 194 of the transistor 128 and the current supply line 140. Therefore, the light shielding film 206 can be formed of a material different from those of the terminals 192 and 194 and the current supply line 140. For example, the light-shielding film 206 may be formed using a metal having a relatively low reflectance such as chromium or molybdenum, or a resin material containing black or a colorant equivalent thereto.

  The display device 350 having such a configuration is advantageous when providing flexibility. This is because the photodiode 156 is protected by the light shielding film 206 in the light irradiation for reducing the adhesive force between the support substrate 170 and the base film 172, and the deterioration of the photodiode 156 due to the light irradiation is prevented. Is possible.

(Ninth embodiment)
In this embodiment, a display device 360 having a structure different from those in the first to eighth embodiments will be described with reference to FIG. The description of the same configuration as in the first to eighth embodiments may be omitted.

  The display device 360 is different from the display device 350 in that the photodiode 156 has a vertical configuration. Specifically, as shown in FIG. 25, the photodiode 156 includes an electrode 202, a p-type semiconductor film 200p, an i-type semiconductor film 200i, an n-type semiconductor film 200n, and an electrode 204 stacked thereon. ing. In FIG. 25, the i-type semiconductor film 200i is stacked on the p-type semiconductor film 200p, and the n-type semiconductor film 200n is stacked thereon. However, the stacking order is not limited to this, and the i-type semiconductor film 200n is formed on the n-type semiconductor film 200n. The p-type semiconductor film 200p may be provided through the type semiconductor film 200i.

  The electrode 202 of the photodiode 156 is connected to the gate of the transistor 150 through the wiring 280. Part of the wiring 280 can function as the gate of the transistor 150.

  As illustrated in FIG. 25, the photodiode 156 can be provided over the first planarization film 190 so as to overlap with the transistor 150 that drives the photodiode 156. For this reason, the size of the sensing element 114 can be reduced, and the display device 100 can be downsized.

(10th Embodiment)
In this embodiment, a display device 370 having a structure different from those of the first to ninth embodiments will be described with reference to FIGS. The description of the same configuration as in the first to ninth embodiments may be omitted.

  The display device 370 is different from the display device 100 in that the emission directions of the first light emitting element 132 and the second light emitting element 154 are the same. Specifically, as indicated by arrows 234 and 235 in FIG. 26, each of the first light-emitting element 132 and the second light-emitting element 154 can be configured such that light is extracted from the counter substrate 104. In this case, the pixel electrodes 210 and 230 of the first light emitting element 132 and the second light emitting element 154 may be configured to reflect visible light. Although not illustrated, the display device 370 may be configured such that light emission is extracted from the first light-emitting element 132 and the second light-emitting element 154 through the substrate 102.

  As an arbitrary configuration, the display device 370 can include a light-shielding film 206 under the photodiode 156 as shown in FIG. Accordingly, the photodiode 156 can selectively sense only light incident from the counter substrate 104. The substrate 102 may be a substrate that does not transmit light. A film or a metal film that does not transmit light may be disposed on the surface of the substrate 102 opposite to the photodiode 156.

  In the display device 370, both image reproduction and light sensing are performed on the counter substrate 104 side. For this reason, information can be input through the screen of the display device 370, and the user's biological information can be acquired by directly touching the screen.

  The embodiments described above as the embodiments of the present invention can be implemented in appropriate combination as long as they do not contradict each other. In addition, what the person skilled in the art appropriately added, deleted, or changed the design of the configuration of each embodiment, or the addition of the process, the omission, or the change of the condition also includes the gist of the present invention. As long as it is provided, it is included in the scope of the present invention.

  In this specification, the case of a display device mainly having a light-emitting element is exemplified as a disclosed example. However, as another application example, other self-luminous display devices, liquid crystal display devices, or electronic devices having an electrophoretic element, etc. Any flat panel display device such as a paper display device can be used. Further, the present invention can be applied without particular limitation from small to medium size.

  Of course, other operational effects different from the operational effects brought about by the aspects of the above-described embodiments are obvious from the description of the present specification or can be easily predicted by those skilled in the art. It is understood that this is brought about by the present invention.

  100: display device, 102: substrate, 104: counter substrate, 106: pixel, 106_1: first pixel, 106_2: second pixel, 108: subpixel, 108B: subpixel, 108G: subpixel, 108R: subpixel Pixel: 110: Drive circuit, 112: Terminal, 114: Sensing element, 120: Scan line, 122: Video signal line, 124: Current supply line, 126: Transistor, 128: Transistor, 130: Capacitor element, 132: First , 134: power supply line, 142: reference signal line, 144: output signal line, 146: reset signal line, 148: gate signal line, 150: transistor, 152: transistor, 154: first 2 light emitting elements, 156: photodiode, 160: scanning line, 162: signal line, 164: transistor, 166: transistor, 68: capacitive element, 170: support substrate, 172: base film, 174: resist mask, 176: resist mask, 180: undercoat, 182: semiconductor film, 184: gate insulating film, 186: gate, 188: interlayer film, 190: first planarization film, 192: terminal, 194: terminal, 196: second planarization film, 198: partition, 200: semiconductor film, 200i: i-type semiconductor film, 200n: n-type semiconductor film, 200p : P-type semiconductor film, 202: electrode, 204: electrode, 206: light shielding film, 210: pixel electrode, 210_1: first layer, 210_2: second layer, 212: EL layer, 214: carrier injection / transport layer 216: Light emitting layer, 217: Light emitting layer, 218: Carrier injection / transport layer, 220: Counter electrode, 230: Elementary electrode, 230_1: First layer, 230_2: 2 layer, 232: reflective electrode, 234: arrow, 235: arrow, 236: arrow, 238: object, 240: passivation layer, 242: first layer, 244: second layer, 246: third layer , 250: adhesive layer, 252: second substrate, 260: reflective film, 280: wiring, 300: display device, 310: display device, 320: display device, 330: display device, 340: display device, 350: display Device, 360: display device, 370: display device

Claims (13)

A substrate,
A pixel located on the substrate and having a sub-pixel and a sensing element;
A first light emitting element provided in the subpixel;
A second light emitting element and a light receiving element provided in the sensing element;
A passivation film covering the first light emitting element and the second light emitting element;
The first light emitting element emits light through the passivation film,
The second light emitting element emits light through the substrate;
The light receiving element is a display device that receives light incident through the substrate. A substrate,
A pixel located on the substrate and having a sub-pixel and a sensing element;
A first light emitting element provided in the subpixel;
A second light emitting element and a light receiving element provided in the sensing element;
A passivation film covering the first light emitting element and the second light emitting element;
The first light emitting element emits light through the substrate;
The second light emitting element emits light through the passivation film,
The display device, wherein the light receiving element receives light incident through the passivation film. A substrate,
A pixel located on the substrate and having a sub-pixel and a sensing element;
A first light emitting element provided in the subpixel;
A second light emitting element and a light receiving element provided in the sensing element;
A passivation film covering the first light emitting element and the second light emitting element;
The first light emitting element emits light through the passivation film,
The second light emitting element emits light through the passivation film,
The display device, wherein the light receiving element receives light incident through the passivation film. Each of the first light emitting element and the second light emitting element is
A pixel electrode;
A light emitting layer on the pixel electrode;
Having a counter electrode on the light emitting layer;
The display device according to claim 1, wherein the counter electrode is shared by the first light emitting element and the second light emitting element.   4. The display device according to claim 1, wherein an emission color of the first light emitting element is the same as an emission color of the second light emitting element. 5.   The display device according to claim 4, further comprising an insulating film that covers an end portion of the pixel electrode of the first light emitting element and an end portion of the pixel electrode of the second light emitting element. The first light emitting element has a light emitting layer,
The display device according to claim 6, wherein the light emitting layer extends from the first light emitting element to the second light emitting element via the insulating film.   The display device according to claim 1, wherein the sensing element has a light shielding film on the light receiving element.   The display device according to claim 2, wherein the sensing element has a light shielding film under the light receiving element. A first scanning line electrically connected to the pixel electrode of the first light emitting element through a transistor;
5. The display device according to claim 4, further comprising a second scanning line electrically connected to the pixel electrode of the second light emitting element without passing through a transistor. A first scanning line electrically connected to the pixel electrode of the first light emitting element through a first transistor;
5. The display device according to claim 4, further comprising a second scanning line electrically connected to the pixel electrode of the second light emitting element via a second transistor.   The display device according to claim 4, wherein the pixel electrode of the first light emitting element and the pixel electrode of the second light emitting element are electrically connected.   The display device according to claim 1, wherein a counter substrate facing the substrate is disposed on a side of the first light emitting element opposite to the substrate.

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