A copolymer organic semiconductor power device with metal field plate

Abstract

The application discloses a copolymer organic semiconductor power device with a metal field plate, which comprises a device body and a metal field plate; the device body comprises, from bottom to top, a substrate, an organic semiconductor layer, a gate insulating layer and a gate metal electrode; the organic semiconductor layer is embedded with a source metal electrode and a drain metal electrode; the organic semiconductor layer between the gate metal electrode and the drain metal electrode is formed into a lateral drift region, and the length of the lateral drift region is not more than 40 um; the metal field plate is deposited on the surface of the gate insulating layer directly above the lateral drift region, and the thickness of the metal field plate is equal to the thickness of the gate metal electrode; the metal field plate is one of a triangular field plate, a strip-shaped field plate and a strip-shaped array field plate, and is specifically selected according to the length of the lateral drift region. The application can realize the electric field regulation of the drift region, so that the on-current of the device can be improved while the voltage resistance performance of the device is improved.

Description

Technical Field

[0001] This invention relates to the field of electronic technology, and in particular to a copolymer organic semiconductor power device having a metal field plate. Background Technology

[0002] In recent years, with the continuous development of the integrated circuit industry, the requirements for power integrated circuits (PICs) have also been increasing. Traditional integrated power devices based on inorganic semiconductor materials are costly and pollute the environment. Therefore, the development of low-cost, skin-friendly, and easy-to-process organic power devices will drive the development of power integrated modules.

[0003] Currently, there are reports of power devices based on organic materials. Organic power devices can withstand higher voltages and exhibit good breakdown voltage performance. However, due to the complex chemical properties of organic semiconductor materials, they are difficult to dopant like traditional inorganic semiconductor materials, resulting in very small on-state current. Furthermore, the electric field in the lateral drift region of the device cannot be controlled, leading to unstable breakdown voltage performance and a high risk of irreversible thermoelectric breakdown. A good trade-off between breakdown voltage performance, drift region electric field control, and on-state current is difficult to achieve in organic power devices, resulting in the contradiction that while current organic power devices have high theoretical breakdown voltage capabilities, they are not practically applicable. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a copolymer organic semiconductor power device with a metal field plate. This copolymer organic semiconductor power device with a metal field plate achieves electric field modulation of the drift region through the metal field plate, thereby improving the device's voltage withstand performance and conduction current.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A copolymer organic semiconductor power device with a metal field plate includes a device body and a metal field plate.

[0007] The device body includes a substrate, an organic semiconductor layer, a gate insulating layer, and a gate metal electrode arranged sequentially from bottom to top.

[0008] An active metal electrode and a drain metal electrode are embedded in the organic semiconductor layer; the organic semiconductor layer located between the gate metal electrode and the drain metal electrode is formed as a lateral drift region, the length of which does not exceed 40 μm.

[0009] A metal field plate is deposited on the surface of the gate insulating layer directly above the lateral drift region, and the thickness of the metal field plate is equal to the thickness of the gate metal electrode.

[0010] The metal field plate is one of the following: triangular field plate, strip field plate, and strip array field plate, and the specific choice depends on the length of the lateral drift region.

[0011] When the length of the lateral drift region is less than 5 μm, the metal field plate is a triangular field plate, which includes several equilateral triangular metal plates arranged at equal intervals along the width direction of the lateral drift region; the apex of each equilateral triangular metal plate points to the drain metal electrode.

[0012] When the length of the lateral drift region is 5 to 20 μm, the metal field plate is a strip-shaped field plate; the strip-shaped field plate includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region, and the length direction of each cuboid metal strip is along the length direction of the device body.

[0013] When the length of the lateral drift region is 20-40 μm, the metal field plate is an array field plate; the array field plate includes several rows of strip arrays arranged equidistantly along the length direction of the lateral drift region; each row of strip arrays includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region, and the length direction of each cuboid metal strip is along the width direction of the device body.

[0014] From the gate metal electrode to the drain metal electrode, the number of cuboid metal strips in each row of strip array gradually decreases.

[0015] The length of the metal field plate shall not exceed the length of the lateral drift zone.

[0016] The gate insulating layer is made of organic insulating materials such as PMMA, PS, PC, or NAS.

[0017] The organic semiconductor layer is made of organic compounds such as P3HT, DPPT-TT, N2200, or pentacene.

[0018] The gate metal electrode, source metal electrode, drain metal electrode, and metal field plate are all made of gold, copper, aluminum, nickel, or titanium.

[0019] Both the gate insulating layer and the organic semiconductor layer are prepared by spin coating or inkjet printing.

[0020] The present invention has the following beneficial effects:

[0021] 1. The metal field plate in this invention can significantly improve the conduction current of the device and effectively avoid the problem of low conduction current in traditional organic semiconductor devices.

[0022] 2. The metal field plate in this invention can significantly regulate the electric field in the lateral drift region when the device body is turned off, effectively adjust and control the electric field distribution on the surface or interface of the device body in the lateral drift region, thereby greatly improving the breakdown voltage of the device.

[0023] 3. The metal field plate in this invention is prepared together with the gate metal electrode by thermal evaporation deposition or magnetron sputtering. Only the required field plate pattern needs to be added to the mask used to prepare the gate metal electrode, without the need for additional processes. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the copolymer organic semiconductor power device of the present invention when the metal field plate is a triangular field plate.

[0025] Figure 2 This is a schematic diagram of the structure of the copolymer organic semiconductor power device of the present invention when the metal field plate is a strip-shaped field plate.

[0026] Figure 3 This is a schematic diagram of the structure of the copolymer organic semiconductor power device of the present invention when the metal field plate is an array field plate.

[0027] Figure 4 A three-dimensional structural diagram of an organic power device in the prior art is shown.

[0028] It includes: 1. Gate metal electrode; 2. Metal field plate; 3. Gate insulating layer; 4. Organic semiconductor layer; 5. Substrate; 6. Source metal electrode; 7. Drain metal electrode; 8. Lateral drift region. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0030] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this 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. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this invention. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.

[0031] like Figures 1 to 3 As shown, a copolymer organic semiconductor power device with a metal field plate includes a device body and a metal field plate 2.

[0032] The device body includes a substrate 5, an organic semiconductor layer 4, a gate insulating layer 3, and a gate metal electrode 1 arranged sequentially from bottom to top.

[0033] The material of the organic semiconductor layer is preferably an organic compound such as P3HT, DPPT-TT, N2200, or pentacene. An active metal electrode 6 and a drain metal electrode 7 are embedded in the organic semiconductor layer; the organic semiconductor layer located between the gate metal electrode and the drain metal electrode is formed as a lateral drift region 8, the length of which does not exceed 40 μm.

[0034] The preferred material for the gate insulating layer is an organic insulating material such as PMMA, PS, PC, or NAS.

[0035] The materials of the aforementioned gate metal electrode, source metal electrode, drain metal electrode, and metal field plate are all gold, copper, aluminum, nickel, or titanium, etc.

[0036] Furthermore, both the gate insulating layer and the organic semiconductor layer are preferably formed by spin coating or inkjet printing.

[0037] Metal field plate 2 is deposited on the surface of the gate insulating layer directly above the lateral drift region, and the thickness of the metal field plate is equal to the thickness of the gate metal electrode. The metal field plate can be fabricated together with the gate metal electrode using thermal evaporation deposition or magnetron sputtering. Only the required field plate pattern needs to be added to the mask used to fabricate the gate metal electrode, without the need for additional processes.

[0038] The length of the aforementioned metal field plate is preferably no more than the length of the lateral drift zone.

[0039] The metal field plate is one of the following: triangular field plate, strip field plate, and strip array field plate, and the specific choice depends on the length of the lateral drift region.

[0040] A. The metal plate is a triangular plate.

[0041] like Figure 1 As shown, when the length of the lateral drift region is less than 5 μm, the drift region is short. Considering the process and usability, neither strip nor array can meet the requirements. Therefore, the metal field plate is selected as a triangular field plate. The triangular field plate includes several equilateral triangular metal plates arranged at equal intervals along the width direction of the lateral drift region. The apex of each equilateral triangular metal plate points to the drain metal electrode.

[0042] The principle of the aforementioned triangular field plate is to disperse the peak electric field, thereby reducing the average electric field and improving the withstand voltage.

[0043] B. The metal field plate is a strip-shaped field plate.

[0044] like Figure 2As shown, when the length of the lateral drift region is 5 to 20 μm, the size of the array field plate is too large to meet the requirements, while the triangular field plate is too small. Therefore, the metal field plate is selected as a strip field plate. The strip field plate includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region. The length direction of each cuboid metal strip is along the length direction of the device body.

[0045] The addition of the aforementioned strip-shaped field plate can make the charge distribution in the drift region linear, thereby modulating the electric field.

[0046] C. The metal field plate is an array field plate.

[0047] like Figure 3 As shown, when the length of the lateral drift region is 20-40 μm, the metal field plate is an array field plate; the array field plate includes several rows of strip arrays arranged equidistantly along the length direction of the lateral drift region; each row of strip arrays includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region, and the length direction of each cuboid metal strip is along the width direction of the device body.

[0048] From the gate metal electrode to the drain metal electrode, the number of cuboid metal strips in each row of strip array gradually decreases.

[0049] The aforementioned array-shaped field plates can disperse the peak electric field, thereby modulating the electric field in the drift region.

[0050] This invention introduces a metal field plate above the lateral drift region of the device, increasing the electric field modulation capability of the lateral drift region, improving the electric field distribution in the lateral drift region, enhancing the device's breakdown voltage stability, and increasing the device's conduction current, thereby significantly improving the device's turn-on and turn-off performance. Compared with a structure without a field plate, the structure with the field plate increases the breakdown voltage by 40%, and the breakdown voltage performance is significantly improved.

[0051] In addition, during the device fabrication process, only the source / drain electrodes and the gate electrode require thermal evaporation deposition. Both the semiconductor layer and the gate dielectric layer can be prepared by spin coating, which has the advantages of simple process and low cost.

[0052] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the protection scope of the present invention.

Claims

1. A copolymer organic semiconductor power device with a metal field plate, characterized in that: It includes a device body and a metal field plate; the device body includes a substrate, an organic semiconductor layer, a gate insulating layer and a gate metal electrode arranged sequentially from bottom to top; An active metal electrode and a drain metal electrode are embedded in an organic semiconductor layer; the organic semiconductor layer located between the gate metal electrode and the drain metal electrode is formed as a lateral drift region, the length of which does not exceed 40 μm; A metal field plate is deposited on the surface of the gate insulating layer directly above the lateral drift region, and the thickness of the metal field plate is equal to the thickness of the gate metal electrode. The metal field plate is one of the following: triangular field plate, strip field plate, and strip array field plate, and the specific selection is based on the length of the lateral drift region; When the length of the lateral drift region is less than 5 μm, the metal field plate is a triangular field plate; the triangular field plate can disperse the electric field peak, thereby reducing the average electric field and improving the withstand voltage. The triangular field plate includes several equilateral triangular metal plates arranged at equal intervals along the width of the lateral drift region; the vertex of each equilateral triangular metal plate points to the drain metal electrode. When the length of the lateral drift region is 5 to 20 μm, the metal field plate is a strip field plate; the strip field plate can make the charge in the drift region linearly distributed, thereby controlling the electric field; the strip field plate includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region, and the length direction of each cuboid metal strip is along the length direction of the device body. When the length of the lateral drift region is 20–40 μm, the metal field plate is an array field plate; the array field plate can disperse the peak electric field, thereby modulating the electric field in the drift region; The array field plate includes several rows of strip arrays arranged equidistantly along the length direction of the lateral drift region; each row of strip arrays includes several cuboid metal strips arranged equidistantly along the width direction of the lateral drift region, and the length direction of each cuboid metal strip is along the width direction of the device body. By introducing a metal field plate above the lateral drift region of the device, the device's conduction current can be increased, the electric field modulation capability of the lateral drift region can be enhanced, the electric field distribution of the lateral drift region can be improved, the device's withstand voltage stability can be improved, and the device's conduction current can be increased, thereby improving the device's turn-on and turn-off performance and increasing the breakdown voltage by 40%.

2. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: From the gate metal electrode to the drain metal electrode, the number of cuboid metal strips in each row of strip array gradually decreases.

3. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: The length of the metal field plate shall not exceed the length of the lateral drift zone.

4. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: The gate insulating layer is made of organic insulating materials such as PMMA, PS, PC, or NAS.

5. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: The organic semiconductor layer is made of organic compounds such as P3HT, DPPT-TT, N2200, or pentacene.

6. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: The gate metal electrode, source metal electrode, drain metal electrode, and metal field plate are all made of gold, copper, aluminum, nickel, or titanium.

7. The copolymer organic semiconductor power device with a metal field plate according to claim 1, characterized in that: Both the gate insulating layer and the organic semiconductor layer are prepared by spin coating or inkjet printing.

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