Micro-led based on cavet regulation

Abstract

This invention provides a CAVET-controlled LED, comprising a CAVET structure and an InGaN layer single quantum well structure. The CAVET includes sequentially arranged n-type Al... 0.2 Ga 0.8 N, intrinsic GaN, current blocking layer, n-doped GaN, p-doped GaN; the Al 0.2 Ga 0.8 The N-layer thickness is 30 nm; the current blocking layer has a p-doping concentration of 1 × 10⁻⁶. ‑ 18 cm ‑3 The single quantum well is composed of In located between n-doped GaN and p-doped GaN. 0.2 Ga 0.8 The In layer consists of N layers; 0.2 Ga 0.8 The N-layer thickness is 3 nm. This invention enables quantum well light emission based on CAVET control, with a light power rise time of 2.4 ns and a fall time of 3.9 ns, which is a faster response speed compared to existing LED control circuits.

Description

Technical Field

[0001] This invention belongs to the field of micro light-emitting diode technology, specifically relating to a Micro-LED based on CAVET regulation. Background Technology

[0002] Micro-LEDs (or micro-LEDs) operate on the same principle as traditional LEDs, emitting light through recombination of holes and electrons in a quantum well under forward bias. Micro-LEDs are micrometers in size, representing a miniaturization and arraying of traditional LEDs. This results in advantages such as small size, energy efficiency, and high luminous efficiency. Besides their wide applications in visible light communication and biomedicine, Micro-LED display technology has also garnered significant attention across various sectors.

[0003] Currently, high-efficiency InGaN-based Micro-LED devices can be fabricated, but the response speed of Micro-LED control circuits still cannot meet the requirements of high-speed information transmission.

[0004] Therefore, this application utilizes the fast response characteristics of CAVET devices to propose an InGaN-based Micro-LED controlled by Current Aperture Vertical Electron Transistor (CAVET) to solve some existing problems. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art, solve the problem of low response rate of current LED control circuits, and provide a Micro-LED based on CAVET control, which reduces the light power rise time to 2.4ns and the fall time to 3.9ns, thereby improving the response rate of this type of Micro-LED to a certain extent.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention provides a CAVET-based Micro-LED, comprising a CAVET, an InGaN layer, and electrodes;

[0008] The InGaN layer is disposed below the n-type GaN layer and above the p-type GaN layer;

[0009] The CAVET comprises an n-type AlGaN layer, an intrinsic GaN layer, a current blocking layer, an n-type GaN layer, and a p-type GaN layer arranged sequentially.

[0010] The electrode includes a gate, a source, and a drain;

[0011] Furthermore, the InGaN layer has a thickness of 3 nm.

[0012] Furthermore, the In composition of the InGaN layer is 0.2.

[0013] Furthermore, the intrinsic GaN thickness is 150 nm.

[0014] Furthermore, the current blocking layer is heavily p-doped GaN with a doping concentration of 1×10⁻⁶. -18 cm -3 .

[0015] Furthermore, the current blocking layer has a width of 2500 nm and a thickness of 300 nm.

[0016] Furthermore, the thickness of the n-type GaN is 2 μm.

[0017] Furthermore, the n-type GaN doping concentration is 1×10⁻⁶. -18 cm-3.

[0018] Furthermore, the p-type GaN has a thickness of 1 μm.

[0019] Furthermore, the p-type GaN doping concentration is 1×10⁻⁶. -18 cm -3 .

[0020] The beneficial effects of this invention are as follows:

[0021] This invention leverages the high mobility of the CAVET structure. By embedding the LED structure within the CAVET device, when the CAVET device is off, the negative voltage at the gate interrupts the two-dimensional electron gas (2DEG) channel generated between the AlGaN / GaN heterojunction. When the CAVET device switches to the on state, the gate voltage rises, and the 2DEG channel opens. Without the ionized impurity scattering of traditional transistors, charge carriers move at high speed through the 2DEG under the influence of the drain bias, recombine, and emit light, thereby improving the response speed of the Micro-LED of this invention. Through this improvement, the optical power rise time of this invention is reduced to 2.4 ns, and the fall time is reduced to 3.9 ns. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the two-dimensional structure of the Micro-LED based on CAVET regulation according to the present invention;

[0023] Figure 2 This is a diagram showing the transfer characteristics of Micro-LED based on CAVET regulation according to the present invention;

[0024] Figure 3The output characteristic curve of the Micro-LED based on CAVET regulation in this invention is shown.

[0025] Figure 4 The timing characteristic curve of the Micro-LED based on CAVET regulation in this invention is shown.

[0026] 1. CAVET (1), 2. InGaN layer, 3. Electrode (3), 11. n-type AlGaN layer, 12. Intrinsic GaN layer, 13. Current blocking layer, 14. n-type GaN layer, 15. p-type GaN layer, 31. Gate, 32. Source, 33. Drain. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0028] Example 1

[0029] This embodiment provides a Micro-LED based on CAVET regulation, reference... Figure 1 The device includes a CAVET1, an InGaN layer 2, and an electrode 3. The CAVET includes an n-type AlGaN layer 11, an intrinsic GaN layer 12, a current blocking layer 13, an n-type GaN layer 14, and a p-type GaN layer 15, wherein the current blocking layer 13 is symmetrically disposed on the outer side of the device; the electrode includes a gate 31, a source 32, and a drain 33, wherein the gate and source are disposed above the n-type AlGaN layer, the drain is disposed below the p-type GaN layer, the gate 31 is disposed at the center of the device, and the source 32 is symmetrically disposed on the outer side.

[0030] In applications, after a forward bias is applied to the drain, electrons move laterally in the 2DEG under the influence of an electric field. Due to the presence of current blocking layers, electrons flow into the quantum well composed of n-type GaN, InGaN, and p-type GaN layers through the current apertures between the blocking layers, and recombine with holes moving from the drain to emit light.

[0031] This invention combines the CAVET structure with the Micro-LED structure, taking advantage of the CAVET structure's lack of ionized impurity scattering and fast carrier mobility, thus successfully improving the response speed of Micro-LEDs.

[0032] Example 2

[0033] Based on Example 1, the AlGaN layer 11 of the CAVET-controlled Micro-LED provided in this example has an Al composition of 0.2 and a thickness of 15 nm; the intrinsic GaN layer 12 has a thickness of 150 nm; and the current blocking layer 13 has a thickness of 300 nm and a doping concentration of 1 × 10⁻⁶. -18 cm -3 The n-type GaN14 has a thickness of 2 μm and a doping concentration of 1 × 10⁻⁶. -18 cm -3 The p-type GaN15 has a thickness of 1 μm and a doping concentration of 1 × 10⁻⁶. -18 cm -3 The InGaN layer 2 has a thickness of 3 nm and an In composition of 0.2%.

[0034] The gate 31 has a width of 5.5 μm; the source 32 has a width of 1 μm; and the drain 33 has a width equal to the structure width of 10 μm.

[0035] In applications, it is essential to ensure that the gate-to-material contact is a Schottky contact, and the source and drain-to-material contact is an ohmic contact.

[0036] In this example application, when the structure of the CAVET-controlled Micro-LED grows upward from p-type GaN15 to n-type AlGaN11, the Al composition of the n-type AlGaN layer must be set to 0.2 along the 0001 direction of GaN spontaneous polarization. This is related to the formation principle of the 2DEG in the AlGaN / GaN structure. At the heterojunction interface of the AlGaN / GaN structure, it is simultaneously affected by both piezoelectric polarization and spontaneous polarization. Piezoelectric polarization is caused by the lattice mismatch between the AlGaN / GaN heterojunction, while spontaneous polarization is caused by the hexagonal lattice structure of GaN itself. These two polarization effects simultaneously cause a large number of positive charges to be fixed on the GaN side of the heterojunction interface, thereby attracting a large number of electrons on the GaN side of the AlGaN / GaN heterojunction interface to form a 2DEG. If the direction of GaN spontaneous polarization is set incorrectly, it will not be able to attract electrons. If the Al composition is set too small, it will not be able to form a lattice mismatch to attract electrons, and if it is too large, it will affect the stability of the structure. Therefore, the structure in this example must be along the 0001 direction of GaN spontaneous polarization, and the Al composition of the n-type AlGaN layer should be set to 0.2.

[0037] Furthermore, the CAVET-controlled Micro-LED provided in this example has a cylindrical structure; the actual structure can be found by referring to [reference needed]. Figure 1 Obtained by central symmetry rotation.

[0038] Example 3

[0039] Based on Example 1 or 2, this example utilizes simulation software to perform simulation. By applying a fixed positive voltage to the source and drain, and changing the gate voltage drop, the transfer characteristic curve of this example is obtained as shown below. Figure 2 As shown; by applying a fixed voltage drop to the gate and changing the source-drain voltage, the output characteristic curve of this example was obtained as shown. Figure 3 As shown. Reference Figure 2 As can be seen, the threshold voltage in this example is approximately -2V. When the gate voltage is less than -2V, no drain current flows. The drain current increases rapidly when the gate voltage is between -2V and 3V, and gradually saturates after the gate voltage reaches 3V. (Reference) Figure 3 It can be seen that when different gate voltages are applied to the gate, the turn-on voltage of the device is around 3V. That is, the device has no leakage current when the source-drain voltage is less than 3V, and starts to conduct when it reaches 3V. The leakage current increases rapidly as the source-drain voltage continues to increase, and the growth trend shows no signs of slowing down within the LED operating voltage range.

[0040] In this application, simulation software is used to perform timing simulations to obtain the rise and fall times. The rise time is defined as the time it takes for the optical power to rise from 10% to 90% of its stable value, and the fall time is defined as the time it takes for the optical power to fall from 90% to 10% of its stable value. (Reference) Figure 4 A fixed voltage is applied between the source and drain. The gate is set to -5V and kept off for 0-30ns, during which the optical power of the device remains at 0. At 30ns, the gate voltage is linearly increased to 0V within 0.1ns and held. The optical power of the device rises rapidly with the increase of the gate voltage and remains at 0.6mW, with a rise time of 2.4ns. At 60ns, the gate voltage is linearly decreased back to -5V within 0.1ns. The optical power of the device rises briefly with the decrease of the gate voltage and then falls rapidly to 0mW, with a fall time of 3.9ns.

[0041] The above embodiments demonstrate that the CAVET-based Micro-LED provided in this example has excellent optical power response capability.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the specific embodiments described above. The specific embodiments and descriptions in the specification are merely for further illustrating the principles of the invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the claims and their equivalents.

[0043] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Additionally, in the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the accompanying drawings of this invention, the fill patterns are only for distinguishing layers and do not constitute any other limitation.

Claims

1. A Micro-LED based on CAVET regulation, characterized in that, Includes CAVET (1), InGaN layer (2), and electrode (3); The CAVET includes an n-type AlGaN layer (11), an intrinsic GaN layer (12), a current blocking layer (13), an n-type GaN layer (14), and a p-type GaN layer (15). The InGaN layer (2) is disposed below the n-type GaN (14) and above the p-type GaN (15); The electrode includes a gate (31), a source (32), and a drain (33).

2. The Micro-LED based on CAVET regulation according to claim 1, wherein, The thickness of the n-type AlGaN layer (11) is 30 nm.

3. The Micro-LED based on CAVET regulation according to claim 1, wherein, The Al composition in the n-type AlGaN layer (11) is 0.

2.

4. The Micro-LED based on CAVET regulation according to claim 1, wherein, The n-doping concentration in the n-type AlGaN layer (11) is 1.5e17.

5. The Micro-LED based on CAVET regulation according to claim 1, wherein, The current blocking layer (13) has a thickness of 300 nm.

6. The Micro-LED based on CAVET regulation according to claim 1, wherein, The p-type doping concentration of the current blocking layer (13) is 1×10⁻⁶. -18 cm -3 .

7. The Micro-LED based on CAVET regulation according to claim 1, wherein, The n-type GaN (14) has a doping concentration of 1 x 1018 -18 cm -3 .

8. The Micro-LED based on CAVET regulation according to claim 1, wherein, The p-type GaN (15) has a doping concentration of 1 x 1018cm-3 -18 cm -3 .

9. The Micro-LED based on CAVET regulation according to claim 1, wherein, The In composition of the InGaN layer (2) is 0.

2.

10. A Micro-LED based on CAVET control according to claim 1, characterized in that, The InGaN layer (2) has a thickness of 3 nm.

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