Double-current-gate regulation and control light-emitting device and display panel

Abstract

The invention, which relates to the photoelectric display field, discloses a double-current-gate regulation light-emitting device comprising a first surface gate, a first electron transport layer, a first surface electrode layer, a second electron transport layer, a light-emitting composite layer, a second hole transport layer, a second surface electrode layer, a first hole transport layer, and a second surface gate. A first bias power supply is applied to the first surface grid and the first surface electrode layer, and a second bias power supply is applied to the second surface grid and the second surface electrode layer; a driving signal is applied between the first surface electrode layer and the second surface electrode layer and is used for driving hole-electrons to be compounded on the light-emitting composite layer and emitting light; the first configuration power supply and the second configuration power supply can regulate and control the electron hole migration amount in the light-emitting composite layer. According to the invention, the current gate structures are additionally arranged on two sides of a traditional light-emitting device, so that the problem of imbalance of electron carrier mobility and hole carrier mobility in the light-emitting composite layer can be effectively solved, the electron-hole light-emitting composite energy efficiency is effectively improved, and meanwhile, the light-emitting brightness and the light-emitting efficiency can be optimized at the same effect.

Description

Technical Field

[0001] The invention relates to the field of optoelectronic display, and in particular to a double current gate controlled light emitting device. Background Art

[0002] As a cutting-edge luminescent material, quantum dots have shown great application potential and trend-setting potential in the field of new display technologies, especially in the development of quantum dot light-emitting diodes (QLEDs), due to their unique properties, such as extremely narrow half-width, high color purity, amazingly high quantum efficiency, and wide spectral range. QLED technology is expected to become a leader in the field of display devices in the future and lead a visual revolution.

[0003] However, despite the broad prospects of QLED technology, in practical applications, the recombination process of charge carriers has become a key factor restricting its luminous efficiency or brightness. In order to achieve the best device efficiency, researchers usually need to carefully design and optimize different functional layers, as well as select quantum dot materials with excellent performance. This process is not only technically complex, but also requires a lot of time, materials and human resources, increasing R&D costs and time cycles.

[0004] What is even more difficult is that due to the natural difference in mobility between electrons and holes, there is often an imbalance of charge carriers in the light-emitting layer of QLED devices. This imbalance makes it difficult for charge carriers in the free state to achieve ideal efficiency when they recombine, which in turn affects the luminescence performance of the entire device. This problem not only plagues the development of QLED technology, but is also common in organic light-emitting diode (OLED) devices, becoming a common problem that restricts the further improvement of the performance of these two types of display technologies.

[0005] Therefore, how to effectively improve the recombination process of charge carriers, balance the mobility of electrons and holes, and improve the luminous efficiency of QLED and OLED devices without increasing too much cost has become a key issue that needs to be urgently solved in the current display technology field. Summary of the invention

[0006] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a dual current gate controlled light-emitting device, aiming to solve the imbalance phenomenon of charge carriers in the light-emitting composite layer in the prior art, and to achieve an improvement in luminous efficiency or luminous brightness through current gate control.

[0007] To achieve the above object, the present invention provides a dual current gate controlled light emitting device, wherein the device structure is stacked in sequence and includes: a first surface gate, a first electron transport layer, a first surface electrode layer, a second electron transport layer, a light emitting composite layer, a second hole transport layer, a second surface electrode layer, a first hole transport layer, and a second surface gate;

[0008] A first bias power supply is applied to a first circuit formed by the first surface gate, the first electron transport layer, and the first surface electrode layer; a second bias power supply is applied to a second circuit formed by the second surface gate, the first hole transport layer, and the second surface electrode layer; a driving signal is applied between the first surface electrode layer and the second surface electrode layer to drive holes-electrons to recombine and emit light in the light-emitting composite layer; the first configuration power supply is used to regulate the electron migration amount of the electron-type carriers of the first surface electrode layer relative to the light-emitting composite layer, and the second configuration power supply is used to regulate the hole migration amount of the hole-type carriers of the second surface electrode layer relative to the light-emitting composite layer, so as to improve the light-emitting efficiency of hole-electron recombination;

[0009] Among them, the first configuration power supply and the second configuration power supply are configured to increase the carrier mobility of the electronic carriers or hole carriers with smaller intrinsic mobility, and reduce the carrier mobility of the hole carriers or electron carriers with larger intrinsic mobility; the intrinsic mobility is: the mobility corresponding to the electronic carriers and the hole carriers respectively when the first bias power supply and the second bias power supply are not applied.

[0010] In this technical solution, by setting current gates on both sides of the device and driving the gate current, the imbalance of the mobility of electrons and holes in the light-emitting composite layer can be effectively solved. The double gates are used to regulate the charge dynamics inside the light-emitting composite layer, effectively improving the electron-hole light-emitting composite energy efficiency between the first gate and the second gate. At the same time, the light-emitting brightness and light-emitting efficiency can be optimized at the same time. At the same time, the shielding effect of the conductive electrode layer is also smaller.

[0011] In a specific implementation, the first bias power supply and the second bias power supply are voltage sources, and the first loop and the second loop are further connected in series with a first current limiting resistor and a second current limiting resistor, respectively.

[0012] This technical solution can limit the current between the surface grid and the surface electrode layer. The first current limiting resistor and the second current limiting resistor are used to control the current of the first loop and the second loop to avoid excessive inter-electrode current and burn out the device.

[0013] In a specific implementation, the first bias power supply and the second bias power supply include: a direct current power supply, an energy storage capacitor, and high and low potential nodes.

[0014] In a specific embodiment, when the intrinsic mobility of the electron-type carriers in the light-emitting composite layer is less than the intrinsic mobility of the hole-type carriers, the first bias power supply and the second bias power supply are configured as follows: the first surface gate applies a negative phase potential relative to the first surface electrode layer to increase the mobility of the electron-type carriers, and the second surface gate applies a negative phase potential relative to the second surface electrode layer to reduce the mobility of the hole-type carriers, so as to improve the luminescence efficiency of the hole-electron recombination.

[0015] In this technical solution, according to the difference in intrinsic mobility between electron carriers and hole carriers, more is withdrawn and less is supplemented. A negative phase potential is applied to the corresponding gate to increase the amount of electron injection, and a negative phase potential is applied to the corresponding gate to reduce the amount of hole injection, thereby improving the hole-electron composite luminescence efficiency when holes are the majority carriers.

[0016] In a specific embodiment, when the intrinsic mobility of the electron-type carriers in the light-emitting composite layer is greater than the intrinsic mobility of the hole-type carriers, the first bias power supply and the second bias power supply are configured as follows: the first surface gate applies a positive potential relative to the first surface electrode layer to reduce the migration amount of the electron-type carriers, and the second surface gate applies a positive potential relative to the second surface electrode layer to increase the migration amount of the hole-type carriers, so as to improve the luminescence efficiency of the hole-electron recombination.

[0017] In this technical solution, according to the difference in intrinsic mobility between electron carriers and hole carriers, more is retreated and less is supplemented. A positive potential is applied by the corresponding gate to reduce the amount of electron injection, and a positive potential is applied by the corresponding gate to increase the amount of hole injection, thereby improving the hole-electron composite luminescence efficiency when electrons are the majority carriers.

[0018] In a specific embodiment, the light-emitting functional structure is LED, OLED or QLED; wherein, when the light-emitting functional structure is the OLED, a first electron injection layer is also included between the first surface gate and the first electron transport layer, and a first hole injection layer is also included between the second surface gate and the first hole transport layer.

[0019] In this technical solution, the carrier transport performance of OLED is optimized by providing an injection layer.

[0020] In a specific embodiment, the first surface electrode layer and the second surface electrode layer are transparent conductive electrodes, at least one of the first surface gate and the second surface gate is a transparent conductive electrode, and the first surface gate or the second surface gate corresponding to the light-emitting side of the light-emitting device structure is a transparent conductive electrode.

[0021] In a specific embodiment, after the first bias power supply and the second bias power supply are regulated, the majority carrier migration amount is reduced, the minority carrier mobility is increased, and the free electrons and holes in the light-emitting composite layer tend to be balanced, so that the light-emitting efficiency is optimized.

[0022] In a specific embodiment, the first bias power supply and the second bias power supply are current sources and the current of the first bias power supply is the same as that of the second bias power supply, the electron mobility of the first electron transport layer and the hole mobility of the first hole transport layer tend to be equal; after being regulated by the first bias power supply and the second bias power supply, the free electrons and holes in the light-emitting composite layer tend to be balanced, so that the light-emitting efficiency is optimized.

[0023] In a second aspect of the present invention, a display panel based on current gate light emission regulation is provided, the panel comprising:

[0024] A panel array composed of a double current gate controlled light emitting device as a unit is provided by the first aspect of the present invention.

[0025] The beneficial effects of the present invention are as follows: 1) The present invention can effectively solve the imbalance problem of the mobility of electrons and holes in the light-emitting composite layer by setting current gates on both sides of the device and driving the gate current. The double gate is used to regulate the charge dynamics inside the light-emitting composite layer, effectively improving the electron-hole light-emitting composite energy efficiency between the first gate and the second gate. At the same time, the luminous brightness and the luminous efficiency can be optimized at the same time. At the same time, the shielding effect of the conductive electrode layer is also smaller. 2) Compared with the voltage-controlled gate, the current gate of the present invention has a fast response speed, a small shielding effect of the conductive electrode layer, and carriers can better penetrate into the light-emitting composite layer. 3) The present invention can balance the migration of electrons and holes through double current gate regulation, and can balance the optimal luminous efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of a double current gate controlled light emitting device in a specific embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of a double current gate controlled light emitting device in which the majority carriers are holes in a specific embodiment of the present invention;

[0028] Figure 3 It is a schematic diagram of a double current gate controlled light emitting device in a specific embodiment of the present invention in which the majority carriers are electrons. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0030] In the description of this patent, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.

[0031] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0032] The embodiment of the present invention provides a dual current gate controlled light emitting device, such as Figure 1 As shown, the device structure is stacked in sequence and includes: a first surface gate 101, a first electron transport layer 102, a first surface electrode layer 103, a second electron transport layer 104, a light-emitting composite layer 105, a second hole transport layer 106, a second surface electrode layer 107, a first hole transport layer 108, and a second surface gate 109;

[0033] A first bias power supply 110 is applied to a first circuit composed of the first surface gate 101, the first electron transport layer 102, and the first surface electrode layer 103; a second bias power supply 111 is applied to a second circuit composed of the second surface gate 109, the first hole transport layer 108, and the second surface electrode layer 107; a driving signal 112 is applied between the first surface electrode layer 103 and the second surface electrode layer 107 to drive holes-electrons to recombine and emit light in the light-emitting composite layer 105; the first configuration power supply is used to regulate the electron migration amount of the electron-type carriers of the first surface electrode layer 103 relative to the light-emitting composite layer 105, and the second configuration power supply is used to regulate the hole migration amount of the hole-type carriers of the second surface electrode layer 107 relative to the light-emitting composite layer 105, so as to improve the luminescence efficiency of hole-electron recombination;

[0034] Among them, the first configuration power supply and the second configuration power supply are configured to increase the carrier mobility of the electronic carriers or hole carriers with smaller intrinsic mobility, and reduce the carrier mobility of the hole carriers or electron carriers with larger intrinsic mobility; the intrinsic mobility is: the mobility corresponding to the electronic carriers and the hole carriers respectively when the first bias power supply 110 and the second bias power supply 111 are not applied.

[0035] The present invention can effectively solve the imbalance problem of the mobility of electrons and holes in the light-emitting composite layer 105 by setting current gates on both sides of the device and driving the gate current. The double gates are used to regulate the electron migration amount and the hole migration amount in the light-emitting composite layer 105 to achieve the effect of improving the luminous efficiency.

[0036] Typically, in this embodiment, the first bias power supply 110 and the second bias power supply 111 are voltage sources, and the first loop and the second loop are further connected in series with a first current limiting resistor and a second current limiting resistor, respectively.

[0037] The first current limiting resistor and the second current limiting resistor are used to control the current of the first loop and the second loop to prevent the inter-electrode current from being too large and burning out the device.

[0038] It is worth mentioning that the first bias power supply 110 and the second bias power supply 111 include: a DC power supply, an energy storage capacitor, and high and low potential nodes.

[0039] In this embodiment, the first bias power supply 110 and the second bias power supply 111 can be current-type power supplies or voltage-type power supplies. For current-type power supplies, providing bias current is more stable than controlling a voltage source, and can more stably regulate the amount of carrier migration.

[0040] It is worth mentioning that in this embodiment, the light-emitting functional structure can be but is not limited to LED, OLED or QLED; wherein, when the light-emitting functional structure is the OLED, a first electron injection layer is also included between the first surface gate 101 and the first electron transport layer 102, and a first hole injection layer is also included between the second surface gate 109 and the first hole transport layer 108.

[0041] Furthermore, the relevant film layers of this embodiment may be transparent for the convenience of display. Typically, the first surface electrode layer 103 and the second surface electrode layer 107 are transparent conductive electrodes, at least one of the first surface gate 101 and the second surface gate 109 is a transparent conductive electrode, and the first surface gate 101 or the second surface gate 109 corresponding to the light-emitting side of the light-emitting device structure is a transparent conductive electrode.

[0042] It is worth mentioning that, for this embodiment, according to the magnitude relationship between the intrinsic mobility of the electron type carriers and the intrinsic mobility of the hole type carriers in the light emitting composite layer 105 (from the perspective of semiconductors, the two are difficult to balance, so the situation where the two are equal is not considered), it can be divided into the following two situations:

[0043] like Figure 2 As shown, when the intrinsic mobility of the electron type carriers in the light emitting composite layer 105 is less than the intrinsic mobility of the hole type carriers, the first bias power supply 110 and the second bias power supply 111 are configured as follows: the first surface gate 101 applies a negative phase potential relative to the first surface electrode layer 103 to increase the migration amount of the electron type carriers, and the second surface gate 109 applies a negative phase potential relative to the second surface electrode layer 107 to reduce the migration amount of the hole type carriers, so as to improve the luminous efficiency of the hole-electron recombination;

[0044] like Figure 3 As shown, when the intrinsic mobility of the electron type carriers in the light-emitting composite layer 105 is greater than the intrinsic mobility of the hole type carriers, the first bias power supply 110 and the second bias power supply 111 are configured as follows: the first surface gate 101 applies a positive potential relative to the first surface electrode layer 103 to reduce the migration amount of the electron type carriers, and the second surface gate 109 applies a positive potential relative to the second surface electrode layer 107 to increase the migration amount of the hole type carriers, so as to improve the luminescence efficiency of the hole-electron recombination.

[0045] Preferably, after being regulated by the first bias power supply 110 and the second bias power supply 111, the majority carrier migration amount is reduced, the minority carrier mobility is increased, and the free electrons and holes in the light-emitting composite layer 105 tend to be balanced, so that the light-emitting efficiency is optimized.

[0046] Preferably, a current source can be used for gate regulation; the first bias power supply 110 and the second bias power supply 111 are current sources and the currents of the first bias power supply 110 and the second bias power supply 111 are the same, the electron mobility of the first electron transport layer 102 and the hole mobility of the first hole transport layer 108 tend to be equal; after regulation by the first bias power supply 110 and the second bias power supply 111, the free electrons and holes in the light-emitting composite layer 105 tend to be balanced, so that the light-emitting efficiency is optimized.

[0047] In a second embodiment of the present invention, a display panel based on current gate light emission regulation is provided, the panel comprising:

[0048] A panel array is formed by using a double current gate controlled light emitting device as a unit provided by the first embodiment.

[0049] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A double current gate controlled light emitting device, characterized in that: The device structure is stacked in sequence and includes: a first surface gate, a first electron transport layer, a first surface electrode layer, a second electron transport layer, a light-emitting composite layer, a second hole transport layer, a second surface electrode layer, a first hole transport layer, and a second surface gate; A first bias power supply is applied to a first circuit formed by the first surface gate, the first electron transport layer, and the first surface electrode layer; a second bias power supply is applied to a second circuit formed by the second surface gate, the first hole transport layer, and the second surface electrode layer; a driving signal is applied between the first surface electrode layer and the second surface electrode layer to drive holes-electrons to recombine and emit light in the light-emitting composite layer; the first configuration power supply is used to regulate the electron migration amount of the electron-type carriers of the first surface electrode layer relative to the light-emitting composite layer, and the second configuration power supply is used to regulate the hole migration amount of the hole-type carriers of the second surface electrode layer relative to the light-emitting composite layer, so as to improve the light-emitting efficiency of hole-electron recombination; Among them, the first configuration power supply and the second configuration power supply are configured to increase the carrier mobility of the electronic carriers or hole carriers with smaller intrinsic mobility, and reduce the carrier mobility of the hole carriers or electron carriers with larger intrinsic mobility; the intrinsic mobility is: the mobility corresponding to the electronic carriers and the hole carriers respectively when the first bias power supply and the second bias power supply are not applied.

2. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: The first bias power supply and the second bias power supply are voltage sources, and the first loop and the second loop are respectively connected in series with a first current limiting resistor and a second current limiting resistor.

3. A dual current gate controlled light emitting device as claimed in claim 1, characterized in that: The first bias power supply and the second bias power supply include: a direct current power supply, an energy storage capacitor, and high and low potential nodes.

4. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: When the intrinsic mobility of the electron-type carriers in the light-emitting composite layer is less than the intrinsic mobility of the hole-type carriers, the first bias power supply and the second bias power supply are configured as follows: the first surface gate applies a negative phase potential relative to the first surface electrode layer to increase the mobility of the electron-type carriers, and the second surface gate applies a negative phase potential relative to the second surface electrode layer to reduce the mobility of the hole-type carriers, so as to improve the luminescence efficiency of the hole-electron recombination.

5. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: When the intrinsic mobility of the electron-type carriers in the light-emitting composite layer is greater than the intrinsic mobility of the hole-type carriers, the first bias power supply and the second bias power supply are configured as follows: the first surface gate applies a positive potential relative to the first surface electrode layer to reduce the migration amount of the electron-type carriers, and the second surface gate applies a positive potential relative to the second surface electrode layer to increase the migration amount of the hole-type carriers, so as to improve the luminescence efficiency of the hole-electron recombination.

6. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: The light-emitting functional structure is LED, OLED or QLED; wherein, when the light-emitting functional structure is the OLED, a first electron injection layer is further included between the first surface gate and the first electron transport layer, and a first hole injection layer is further included between the second surface gate and the first hole transport layer.

7. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: The first surface electrode layer and the second surface electrode layer are transparent conductive electrodes, at least one of the first surface gate and the second surface gate is a transparent conductive electrode, and the first surface gate or the second surface gate corresponding to the light output side of the light emitting device structure is a transparent conductive electrode.

8. A double current gate controlled light emitting device as claimed in claim 4 or 5, characterized in that: After being regulated by the first bias power supply and the second bias power supply, the migration amount of majority carriers is reduced, the mobility of minority carriers is increased, and the free electrons and holes in the light-emitting composite layer tend to be balanced, so that the light-emitting efficiency is optimized.

9. A double current gate controlled light emitting device as claimed in claim 1, characterized in that: The first bias power supply and the second bias power supply are current sources and the current of the first bias power supply is the same as that of the second bias power supply, the electron mobility of the first electron transport layer and the hole mobility of the first hole transport layer tend to be equal; after being regulated by the first bias power supply and the second bias power supply, the free electrons and holes in the light-emitting composite layer tend to be balanced, so that the light-emitting efficiency is optimized.

10. A display panel based on current gate light emission regulation, characterized in that: The panel comprises: A panel array composed of a double current gate controlled light emitting device as provided in any one of claims 1 to 9 as a unit.

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