A humanoid robotic arm high load off power mos structure with enhanced p-gan cap layer

Abstract

This invention relates to the field of gallium nitride (GaN) semiconductor technology and discloses a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer. The structure includes a substrate, a gallium nitride (GaN) structure, and a MOS structure. The GaN structure includes a buffer layer, a GaN layer, an aluminum gallium nitride (AlGaN) layer, a drain, a GaN gate, and a P-GaN layer. The MOS structure includes an N-diffusion layer, a P-well layer, an N-well layer, a P+ layer, a source, and a MOS gate. The MOS structure is located on the surface of the AlGaN layer and to the left of the GaN gate, with the N-diffusion layer in direct contact with the AlGaN layer. This invention integrates a silicon-based MOS structure onto the surface of a GaN device and achieves direct contact between the MOS gate and the GaN gate, thus constructing an enhanced P-GaN cap layer power MOS structure. By combining the high electron mobility of GaN material with the low-power control capability of the MOS structure, this invention significantly improves the device's response speed and system reliability under high-load, frequent turn-off conditions.

Description

Technical Field

[0001] This invention relates to the field of gallium nitride semiconductor technology, and more particularly to a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer. Background Technology

[0002] In high-load industrial automation equipment such as robotic arms, power MOS devices need to withstand the high voltage and high current surges caused by frequent start-stop operations. Although existing enhanced gallium nitride power devices have the advantages of high frequency and low loss, their gate structure still faces problems such as electric field concentration, threshold drift caused by hot carrier injection, and reliability degradation under long-term high-load turn-off conditions. At the same time, traditional silicon-based MOS devices are difficult to balance voltage withstand and switching speed, making it difficult to meet the stringent requirements of high-performance robot drive systems for stability and dynamic response.

[0003] An existing patent discloses a partial P-GaN cap layer and a reverse gradient barrier enhanced radio frequency HEMT and its fabrication method (publication number CN118367020A). The technology disclosed in this existing patent suffers from current collapse and gate leakage current problems due to electroactive buffer traps near the AlGaN / GaN heterojunction. Summary of the Invention

[0004] This invention provides a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer to solve existing technical problems. It addresses the technical issues of slow turn-off response and reduced reliability caused by concentrated gate electric field in power MOS devices under high-load and frequent turn-off conditions.

[0005] To solve the above-mentioned technical problems, according to one aspect of the present invention, more specifically, a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer is provided, comprising a substrate, a gallium nitride structure, and a MOS structure; the gallium nitride structure comprises a buffer layer, a gallium nitride layer, an aluminum gallium nitride layer, a drain, a gallium nitride gate, and a P-gallium nitride layer; The MOS structure includes an N-diffusion layer, a P-well layer, an N-well layer, a P+ layer, a source, and a MOS gate. The MOS structure is located on the surface of the aluminum gallium nitride layer and to the left of the gallium nitride gate. The N-diffusion layer is in direct contact with the aluminum gallium nitride layer. The MOS gate is in direct contact with the gallium nitride gate. The source serves as the source of the high-load shutdown power MOS structure of the robotic arm. The N-diffusion layer serves as the source of the gallium nitride structure. The drain serves as the drain of the high-load shutdown power MOS structure of the robotic arm.

[0006] Furthermore, dielectric layers are deposited between the drain and the gallium nitride gate, between the gallium nitride gate and the N-diffusion layer, and below the MOS gate.

[0007] Furthermore, the P-gallium nitride layer is located between the gallium nitride gate and the aluminum gallium nitride layer.

[0008] Furthermore, the P-type gallium nitride layer also includes a P-type gallium nitride layer and a P+ type gallium nitride layer.

[0009] Furthermore, the P-type gallium nitride layer and the P+ type gallium nitride layer are arranged alternately, and there are at least two of each type. A p-type gallium nitride layer refers to a p-type gallium nitride region with a relatively low doping concentration. Its key feature is that by controlling the doping amount of trivalent elements (such as boron), the hole concentration is kept low, resulting in a relatively gentle electric field distribution below the gate. The function of this layer is to optimize the electric field management of the gate region, reduce gate leakage current, and improve the device's voltage withstand capability and switching stability. It is particularly suitable for high-load, frequent-turn-off operating environments. P+ type gallium nitride layer refers to a P-type gallium nitride region with a relatively high doping concentration. It has a high hole concentration, which can effectively reduce contact resistance and enhance the gate's control over the channel. Its function is to improve the gate's injection efficiency and switching response speed. At the same time, by alternating with the P- type layer, it forms a local electric field modulation structure, further enhancing the device's breakdown voltage and reliability.

[0010] Furthermore, a lightly doped gallium nitride layer is deposited inside the aluminum gallium nitride layer and below the gallium nitride gate; A lightly doped gallium nitride (GaN) layer refers to a lightly doped P-type region formed by ion implantation within or at the interface of an aluminum gallium nitride (GaN) layer. Its main function is to act as an electric field buffer layer, mitigating the electric field concentration effect at the gate edge and suppressing hot carrier injection and device degradation. This layer can also improve the carrier distribution under the gate, enhance the stability of the threshold voltage, and thus strengthen the turn-off capability and long-term reliability of the entire power MOS structure under high load conditions.

[0011] Furthermore, the low-doped gallium nitride layer is in direct contact with the P-type gallium nitride layer and the P+ type gallium nitride layer, and the width of the cross-sectional profile of the low-doped gallium nitride layer exceeds the width of the cross-sectional profile of the gallium nitride gate.

[0012] Furthermore, a lightly doped gallium nitride layer is formed between the gallium nitride layer and the aluminum gallium nitride layer through ion implantation.

[0013] Furthermore, heavily doped gallium nitride particles are formed inside the lightly doped gallium nitride layer and in the region below the gallium nitride gate by ion implantation.

[0014] This invention provides a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer. Compared with existing technologies, the advantages achieved by this method are: 1. This invention integrates a silicon-based MOS structure onto the surface of a gallium nitride device and achieves direct contact between the MOS gate and the gallium nitride gate, thus constructing an enhanced P-GaN cap layer power MOS structure. By combining the high electron mobility of gallium nitride material with the low power consumption control capability of the MOS structure, the response speed and system reliability of the device under high load and frequent shutdown conditions are significantly improved.

[0015] 2. This invention introduces a structure of alternating P-type and P+ type gallium nitride layers in the P-type gallium nitride layer to form a local electric field modulation effect. This optimizes the electric field distribution under the gate, reduces leakage current, and enhances the gate injection efficiency and switching speed, thereby effectively improving the device's withstand voltage and breakdown voltage. It is suitable for industrial applications with high loads and frequent start-stop cycles.

[0016] 3. The present invention deposits a lightly doped gallium nitride layer with a width exceeding the gate cross-section inside the aluminum gallium nitride layer and below the gallium nitride gate, as an electric field buffer layer, which effectively alleviates the electric field concentration effect at the gate edge, suppresses hot carrier injection and device degradation, and improves the stability of the threshold voltage, thereby enhancing the device's turn-off capability and long-term reliability under high load conditions.

[0017] 4. This invention forms a lightly doped gallium nitride layer between the gallium nitride layer and the aluminum gallium nitride layer, and injects heavily doped gallium nitride particles into the region below the gate inside the layer. This achieves fine doping control of the key area, which not only ensures the overall withstand voltage performance, but also optimizes the local switching characteristics, and significantly improves the dynamic response capability and energy efficiency of the device. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention; Figure 4 This is a schematic diagram of the structure of Embodiment 4 of the present invention.

[0019] In the figure: 1. Substrate; 2. Gallium nitride structure; 3. MOS structure; 4. Dielectric layer; 201. Buffer layer; 202. Gallium nitride layer; 203. Aluminum gallium nitride layer; 204. Drain; 205. Gallium nitride gate; 206. P-type gallium nitride layer; 207. P-type gallium nitride layer; 208. P+ type gallium nitride layer; 209. Lightly doped gallium nitride layer; 210. Lightly doped gallium nitride layer; 211. Heavily doped gallium nitride particle; 301. N-diffusion layer; 302. P-well layer; 303. N-well layer; 304. P+ layer; 305. Source; 306. MOS gate. Detailed Implementation

[0020] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Example 1 like Figure 1 As shown, according to one aspect of the present invention, a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer is provided, including a substrate 1, a gallium nitride structure 2, and a MOS structure 3; the gallium nitride structure 2 includes a buffer layer 201, a gallium nitride layer 202, an aluminum gallium nitride layer 203, a drain 204, a gallium nitride gate 205, and a P-gallium nitride layer 206; the MOS structure 3 includes an N-diffusion layer 301, a P-well layer 302, an N-well layer 303, a P+ layer 304, a source 305, and a MOS gate 306, the MOS structure 3 being located on the surface of the aluminum gallium nitride layer 203 and to the left of the gallium nitride gate 205, and the N-diffusion layer 301 being in direct contact with the aluminum gallium nitride layer 203; The MOS gate 306 is in direct contact with the gallium nitride gate 205. The source 305 serves as the source of the high-load turn-off power MOS structure of the robotic arm, the N-diffusion layer 301 serves as the source of the gallium nitride structure 2, and the drain 204 serves as the drain of the high-load turn-off power MOS structure of the robotic arm.

[0022] In this embodiment, dielectric layers 4 are deposited between the drain 204 and the gallium nitride gate 205, between the gallium nitride gate 205 and the N-diffusion layer 301, and below the MOS gate 306. The P-gallium nitride layer 206 is located between the gallium nitride gate 205 and the aluminum gallium nitride layer 203.

[0023] This embodiment integrates the MOS structure 3 onto the surface of the gallium nitride (GaN) structure 2 and achieves direct contact between the MOS gate 306 and the GaN gate 205, constructing a novel enhanced P-GaN cap-layer power MOS structure. The N-diffusion layer 301 serves as the source of the GaN structure 2, directly contacting the aluminum gallium nitride (AGaN) layer 203. Simultaneously, the source 305 serves as the source of the overall structure, and the drain 204 serves as the drain, achieving functional integration of the GaN device and the silicon-based MOS device. The deposition of the dielectric layer 4 in critical areas effectively isolates interference between electrodes, improving the stability and reliability of the device.

[0024] The advantage of this design lies in its enhanced gate control capability through direct gate contact, enabling the device to respond quickly and turn off stably under high load conditions. This makes it particularly suitable for industrial applications such as robotic arms that require frequent start-stop cycles. Simultaneously, the high electron mobility and breakdown voltage of gallium nitride material, combined with the low-power control capability of the MOS structure, significantly improves the overall efficiency and reliability of the power system.

[0025] Example 2 like Figure 2 As shown, according to one aspect of the present invention, a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer is provided, including a substrate 1, a gallium nitride structure 2, and a MOS structure 3; the gallium nitride structure 2 includes a buffer layer 201, a gallium nitride layer 202, an aluminum gallium nitride layer 203, a drain 204, a gallium nitride gate 205, and a P gallium nitride layer 206; the MOS structure 3 includes an N diffusion layer 301, a P well layer 302, an N well layer 303, a P+ layer 304, a source 305, and a MOS gate 306.

[0026] In this embodiment, the P-type gallium nitride layer 206 further includes a P-type gallium nitride layer 207 and a P+ type gallium nitride layer 208. In this embodiment, the P-type gallium nitride layer 207 and the P+ type gallium nitride layer 208 are arranged alternately, and there are at least two of each type. The p-type gallium nitride layer 207 refers to a p-type gallium nitride region with a relatively low doping concentration. Its key feature is the control of the doping amount of trivalent elements such as boron, resulting in a low hole concentration and thus a relatively gentle electric field distribution below the gate. This layer optimizes the electric field management of the gate region, reduces gate leakage current, and improves the device's withstand voltage and switching stability, making it particularly suitable for high-load, frequent-turn-off operating environments. The P+ type gallium nitride layer 208 refers to a relatively highly doped P-type gallium nitride region with a high hole concentration, which effectively reduces contact resistance and enhances the gate's control over the channel. Its function is to improve gate injection efficiency and switching response speed. Simultaneously, by alternating with the P-type layer, it forms a local electric field modulation structure, further enhancing the device's breakdown voltage and reliability.

[0027] This embodiment introduces an alternating structure of P-type gallium nitride layers 207 and P+ type gallium nitride layers 208 within the P-type gallium nitride layer 206. This utilizes the different doping concentrations of the P-type regions to create a localized electric field modulation effect. The P-type layers, with their lower doping concentration, create a smooth electric field distribution, reducing gate leakage current; while the P+ type layers, with their higher doping concentration, enhance gate injection efficiency and improve switching speed. This alternating arrangement effectively balances the conflict between electric field concentration and conduction losses, optimizing electric field management beneath the gate.

[0028] Its advantages lie in the fact that this "concentration gradient" design not only improves the device's withstand voltage and breakdown voltage, but also enhances the gate's control precision over the channel, reducing switching losses. Under high-load, frequent turn-off conditions, this structure can effectively suppress hot carrier injection and device degradation, extend service life, and improve the overall reliability and stability of the system.

[0029] Example 3 like Figure 3 As shown, according to one aspect of the present invention, a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer is provided, including a substrate 1, a gallium nitride structure 2, and a MOS structure 3; the gallium nitride structure 2 includes a buffer layer 201, a gallium nitride layer 202, an aluminum gallium nitride layer 203, a drain 204, a gallium nitride gate 205, and a P gallium nitride layer 206; the MOS structure 3 includes an N diffusion layer 301, a P well layer 302, an N well layer 303, a P+ layer 304, a source 305, and a MOS gate 306.

[0030] In this embodiment, a lightly doped gallium nitride (GaN) layer 209 is deposited inside the aluminum gallium nitride (AGaN) layer 203 and below the GaN gate 205. The lightly doped GaN layer 209 refers to a lightly doped P-type region formed by ion implantation inside or at the interface of the AGaN layer. Its main function is to act as an electric field buffer layer, alleviating the electric field concentration effect at the gate edge and suppressing hot carrier injection and device degradation. This layer can also improve the carrier distribution below the gate, enhance the stability of the threshold voltage, and thus enhance the turn-off capability and long-term reliability of the entire power MOS structure under high load conditions.

[0031] In this embodiment, the low-doped gallium nitride layer 209 is in direct contact with the P-type gallium nitride layer 207 and the P+ type gallium nitride layer 208, and the width of the cross-sectional profile of the low-doped gallium nitride layer 209 exceeds the width of the cross-sectional profile of the gallium nitride gate 205.

[0032] In this embodiment, a lightly doped gallium nitride (GaN) layer 209 is deposited inside the aluminum gallium nitride (GaN) layer 203 and below the GaN gate 205. This lightly doped layer is in direct contact with the P-type GaN layer 207 and the P+ type GaN layer 208, and its width exceeds the gate width. This lightly doped layer acts as an electric field buffer layer, effectively mitigating the electric field concentration effect at the gate edge and preventing excessively high local electric fields from causing device breakdown or degradation. Simultaneously, its wider layout than the gate ensures uniform electric field distribution, further improving the device's breakdown voltage capability.

[0033] The advantage of this design lies in the significant improvement of the electric field distribution and carrier behavior beneath the gate through the introduction of a low-doped layer, which suppresses the hot carrier effect and enhances the stability of the threshold voltage. This not only strengthens the device's turn-off capability under high load conditions but also improves its long-term operational reliability, making it more suitable for industrial robot control systems with extremely high requirements for stability and safety.

[0034] Example 4 like Figure 4As shown, according to one aspect of the present invention, a high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer is provided, including a substrate 1, a gallium nitride structure 2, and a MOS structure 3; the gallium nitride structure 2 includes a buffer layer 201, a gallium nitride layer 202, an aluminum gallium nitride layer 203, a drain 204, a gallium nitride gate 205, and a P gallium nitride layer 206; the MOS structure 3 includes an N diffusion layer 301, a P well layer 302, an N well layer 303, a P+ layer 304, a source 305, and a MOS gate 306.

[0035] In this embodiment, a lightly doped gallium nitride layer 210 is formed between the gallium nitride layer 202 and the aluminum gallium nitride layer 203 by ion implantation. Heavily doped gallium nitride particles 211 are formed inside the lightly doped gallium nitride layer 210 and in the region below the gallium nitride gate 205 by ion implantation.

[0036] In this embodiment, a lightly doped gallium nitride layer 210 is formed between the gallium nitride layer 202 and the aluminum gallium nitride layer 203 by ion implantation. Then, heavily doped gallium nitride particles 211 are further implanted within this layer, in the region below the gallium nitride gate 205. This "dual-layer implantation" structure enables precise doping control of the region below the gate. The lightly doped layer provides an electric field buffer, while the heavily doped particles locally enhance gate control capability, forming a localized highly conductive channel and improving switching response speed.

[0037] Its advantage lies in the precise control achieved through ion implantation technology, enabling "customized" doping of key areas of the device. This ensures both overall withstand voltage performance and optimizes local switching characteristics. This structure improves switching speed and reduces on-resistance while maintaining high breakdown voltage and degradation resistance, making it particularly suitable for high-frequency, high-load robotic arm drive applications, significantly enhancing the system's dynamic response and energy efficiency.

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer, comprising a substrate (1), a gallium nitride structure (2), and a MOS structure (3); wherein the gallium nitride structure (2) comprises a buffer layer (201), a gallium nitride layer (202), an aluminum gallium nitride layer (203), a drain (204), a gallium nitride gate (205), and a P-gallium nitride layer (206); The MOS structure (3) includes an N-diffusion layer (301), a P-well layer (302), an N-well layer (303), a P+ layer (304), a source (305), and a MOS gate (306), characterized in that: The MOS structure (3) is located on the surface of the aluminum gallium nitride layer (203) and to the left of the gallium nitride gate (205), and the N diffusion layer (301) is in direct contact with the aluminum gallium nitride layer (203); The MOS gate (306) is in direct contact with the gallium nitride gate (205), the source (305) serves as the source of the high-load shutdown power MOS structure of the robotic arm, the N-diffusion layer (301) serves as the source of the gallium nitride structure (2), and the drain (204) serves as the drain of the high-load shutdown power MOS structure of the robotic arm.

2. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 1, characterized in that: A dielectric layer (4) is deposited between the drain (204) and the gallium nitride gate (205), between the gallium nitride gate (205) and the N diffusion layer (301), and below the MOS gate (306).

3. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 1, characterized in that: The P-gallium nitride layer (206) is located between the gallium nitride gate (205) and the aluminum gallium nitride layer (203).

4. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 1, characterized in that: The P-type gallium nitride layer (206) further includes a P-type gallium nitride layer (207) and a P+ type gallium nitride layer (208).

5. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 4, characterized in that: The P-type gallium nitride layer (207) and the P+ type gallium nitride layer (208) are arranged alternately, and there are at least two of each type.

6. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 4, characterized in that: A lightly doped gallium nitride layer (209) is deposited inside the aluminum gallium nitride layer (203) and below the gallium nitride gate (205).

7. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 6, characterized in that: The low-doped gallium nitride layer (209) is in direct contact with the P-type gallium nitride layer (207) and the P+ type gallium nitride layer (208), and the width of the cross-sectional profile of the low-doped gallium nitride layer (209) exceeds the width of the cross-sectional profile of the gallium nitride gate (205).

8. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 1, characterized in that: A lightly doped gallium nitride layer (210) is formed between the gallium nitride layer (202) and the aluminum gallium nitride layer (203) by ion implantation.

9. The high-load turn-off power MOS structure for a humanoid robotic arm with an enhanced P-GaN cap layer according to claim 8, characterized in that: The region inside the lightly doped gallium nitride layer (210) and below the gallium nitride gate (205) is formed with heavily doped gallium nitride particles (211) by ion implantation.

Images