Structure and fabrication method of GaN HEMT device with anti-destructive breakdown function
By introducing a pN diode with a breakdown voltage lower than its own in GaN HEMT devices, the destructive breakdown problem when a large voltage is applied between the source and drain is solved, realizing the device's anti-destructive breakdown function and improving the device's performance and reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FUDAN UNIVERSITY
- Filing Date
- 2023-03-07
- Publication Date
- 2026-07-03
AI Technical Summary
Traditional GaN HEMT devices are prone to destructive breakdown when large voltages or continuous high-voltage stress are applied between the source and drain, which cannot meet the requirements of industrial fields such as electric vehicles.
A pN diode with a breakdown voltage lower than that of the GaN HEMT device is introduced between the second nucleation layer and the GaN buffer layer of the GaN HEMT device. When a large voltage is applied between the source and drain, the pN diode will first undergo avalanche breakdown, thereby protecting the GaN HEMT device from destructive breakdown.
This effectively protects GaN HEMT devices from destructive breakdown under high field conditions, improving device performance and reliability.
Smart Images
Figure CN116314318B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor devices, and more particularly to a GaN HEMT device structure and fabrication method with anti-destructive breakdown function. Background Technology
[0002] AlGaN / GaN HEMT, short for AlGaN / GaN high electron mobility transistor, is a semiconductor device based on an AlGaN / GaN heterostructure. Due to the polarization effect in AlGaN / GaN HEMT devices, a quantum potential well is formed at the heterojunction interface between AlGaN and GaN materials, generating a high-density, high-electron-mobility two-dimensional electron gas (2DEG). Therefore, compared to Si devices, AlGaN / GaN HEMT transistors have higher breakdown voltage, higher frequency response, and lower conduction losses.
[0003] However, unlike Si and SiC-based power devices, traditional GaN-HEMT devices exhibit near-zero avalanche breakdown characteristics, leading to destructive breakdowns and failing to meet the requirements of many industrial sectors, such as electric vehicles, for GaN HEMT devices. Therefore, developing an AlGaN / GaN HEMT device that can protect GaN HEMT devices from destructive breakdown under high voltage or continuous high-voltage stress applied between the source and drain has become a key technical challenge for those skilled in the art. Summary of the Invention
[0004] This invention provides a GaN HEMT device structure and fabrication method with anti-destructive breakdown function to solve the problem of how to protect GaN HEMT devices from destructive breakdown under the action of high source-drain electric fields.
[0005] According to a first aspect of the present invention, a GaN HEMT device structure with anti-destructive breakdown function is provided, comprising:
[0006] A substrate, wherein a first nucleation layer and a GaN buffer layer are sequentially formed on the substrate in a direction away from the substrate;
[0007] The pN diode includes a p+ doped region and an N+ doped region formed on a first region and a second region of the surface of the GaN buffer layer, respectively, and an anode and a cathode formed on the p+ doped region and the N+ doped region, respectively; wherein the first region and the second region are opposite sides of the surface of the GaN buffer layer.
[0008] GaN HEMT devices are formed on the GaN buffer layer;
[0009] The breakdown voltage of the pN diode is lower than that of the GaN HEMT device.
[0010] Optionally, the pN diode further includes: an anode metal interconnect layer and an anode field plate formed at the top of the anode; and a cathode metal interconnect layer formed at the top of the cathode;
[0011] The anode field plate is formed on top of the anode metal interconnect layer.
[0012] Optionally, the GaN HEMT device includes:
[0013] A second nucleation layer, a channel layer, and a barrier layer are sequentially formed on the GaN buffer layer in a direction away from the GaN buffer layer;
[0014] The source, gate, and drain are formed on the barrier layer;
[0015] A source metal interconnect layer, a gate metal interconnect layer, and a drain metal interconnect layer are respectively formed at the top of the source, the gate, and the drain; wherein, the gate includes a p-GaN layer and a gate metal layer formed at the top of the p-GaN layer;
[0016] A passivation layer formed on the barrier layer and filling the gaps between the source metal interconnect layer, the gate metal interconnect layer, and the drain metal interconnect layer; and
[0017] Gate field plate: The gate field plate is formed on the passivation layer at the top of the gate and is connected to the source metal interconnect layer.
[0018] Optionally, the GaN HEMT device structure with anti-damage breakdown structure function further includes: a drain field plate; the drain field plate is formed on the passivation layer between the drain metal interconnect layer and the cathode metal interconnect layer and connects the drain metal interconnect layer and the cathode metal interconnect layer.
[0019] Optionally, the GaN HEMT device structure with anti-damage breakdown structure function also includes:
[0020] A passivation layer formed on the GaN buffer layer and filling the gaps between the source metal interconnect layer and the anode metal interconnect layer, as well as between the drain metal interconnect layer and the cathode metal interconnect layer.
[0021] Optionally, the materials of the first nucleation layer and the second nucleation layer are AlN, the material of the channel layer is GaN, and the material of the barrier layer is AlGaN.
[0022] According to a second aspect of the present invention, a method for fabricating a GaN HEMT device structure with a destructive breakdown protection function is provided, comprising:
[0023] Provide a substrate;
[0024] A first nucleation layer and a GaN buffer layer are sequentially formed on the substrate in a direction away from the substrate; and
[0025] A pN diode and a GaN HEMT device are formed; the pN diode is formed in the surface layer of the GaN buffer layer;
[0026] The pN diode includes: a p+ doped region and an N+ doped region formed on the surface of the GaN buffer layer in a first region and a second region, respectively, and an anode and a cathode formed on the p+ doped region and the N+ doped region, respectively.
[0027] The GaN HEMT device is formed on a portion of the GaN buffer layer;
[0028] The breakdown voltage of the pN diode is lower than the breakdown voltage of the GaN HEMT device.
[0029] Optionally, the specific steps for forming a pN diode and a GaN HEMT device include:
[0030] p+ ions and N+ ions are implanted in the first region and the second region respectively, and the p+ ions and N+ ions are activated to form the p+ doped region and the N+ doped region;
[0031] A second nucleation layer, a channel layer, a barrier layer, and a p-GaN layer are sequentially formed on the GaN buffer layer in a direction away from the GaN buffer layer and are then mesa-isolated; the p-GaN layer covers a portion of the surface of the barrier layer.
[0032] A source, drain, anode, and cathode are formed; the anode and the cathode are formed on the GaN buffer layer on both sides of the GaN HEMT device along the first direction; the source and the drain are formed on the barrier layer on both sides of the p-GaN layer along the first direction.
[0033] A gate is formed; the gate includes the p-GaN layer and a gate metal layer; the gate metal layer is formed on top of the p-GaN layer;
[0034] A passivation layer is deposited at the top of the gate;
[0035] A source metal interconnect layer, a drain metal interconnect layer, a gate metal interconnect layer, an anode metal interconnect layer, and a cathode metal interconnect layer are respectively formed at the top ends of the source, the drain, the gate, the anode, and the cathode; and
[0036] This forms the gate field plate, anode field plate, and drain field plate.
[0037] Optionally, forming a second nucleation layer, a channel layer, a barrier layer, and a p-GaN layer sequentially on the GaN buffer layer along a direction away from the GaN buffer layer and performing mesa isolation specifically includes:
[0038] The second nucleation layer, the channel layer, the barrier layer, and the p-GaN layer are sequentially epitaxially on the GaN buffer layer in a direction away from the GaN buffer layer;
[0039] The mesa isolation is achieved by etching the second nucleation layer, the channel layer, the barrier layer, and both ends of the p-GaN layer along the first direction, thereby exposing part of the GaN buffer layer.
[0040] Photoresist is coated on the exposed GaN buffer layer and the p-GaN layer, and the photoresist is exposed and developed to form a patterned photoresist.
[0041] Using the patterned photoresist as a mask, the p-GaN layer is etched on both sides of the p-GaN layer along the first direction to expose a portion of the barrier layer;
[0042] Remove the patterned photoresist to form the p-GaN layer covering a portion of the barrier layer.
[0043] Optionally, forming the gate specifically includes:
[0044] A passivation layer is deposited; the passivation layer is formed on the barrier layer and the GaN buffer layer and fills the voids between the source, the drain, the cathode and the anode;
[0045] The passivation layer at the top of the p-GaN layer is etched to form a gate cavity;
[0046] The gate metal layer is deposited in the gate cavity to form the gate.
[0047] According to a third aspect of the present invention, an electronic device is provided, comprising a GaN HEMT device structure having a tamper-proof breakdown structure as described in any of the first aspects of the present invention.
[0048] According to a fourth aspect of the present invention, a method for manufacturing an electronic device is provided, comprising the method for manufacturing a GaN HEMT device structure having a destructive breakdown protection function as described in any of the second aspects of the present invention.
[0049] This invention provides a GaN HEMT device structure with anti-destructive breakdown function. A pN diode is introduced between the second nucleation layer and the GaN buffer layer at the bottom of the GaN HEMT device. Since the breakdown voltage of the introduced pN diode is lower than that of the GaN HEMT device, when a large voltage or continuous high-voltage stress is applied between the source and drain of the GaN HEMT device, the pN diode undergoes avalanche breakdown, thus protecting the GaN HEMT device from destructive breakdown. Therefore, the technical solution provided by this invention solves the problem of destructive breakdown in GaN HEMT devices when a large voltage or continuous high-voltage stress is applied between the source and drain, thereby improving the performance of GaN HEMT devices. Attached Figure Description
[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0051] Figure 1 This is a schematic flowchart of a method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function according to an embodiment of the present invention;
[0052] Figure 2 This is a schematic diagram of different process stages of a GaN HEMT device structure fabricated according to a method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function, as provided in an embodiment of the present invention. Figure 1 ;
[0053] Figure 3 This is a schematic diagram of different process stages of a GaN HEMT device structure fabricated according to a method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function, as provided in an embodiment of the present invention. Figure 2 ;
[0054] Figure 4 This is a schematic diagram of different process stages of a GaN HEMT device structure fabricated according to a method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function, as provided in an embodiment of the present invention. Figure 3 ;
[0055] Figure 5 This is a schematic diagram of different process stages of a GaN HEMT device structure fabricated according to a method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function, as provided in an embodiment of the present invention. Figure 4 ;
[0056] Explanation of reference numerals in the attached figures:
[0057] 101-Substrate;
[0058] 102 - First nucleation layer;
[0059] 103-GaN buffer layer;
[0060] 104-N + Doped regions;
[0061] 105-p + Doped regions;
[0062] 106 - Anode;
[0063] 107 - Cathode;
[0064] 108 - Second nucleation layer;
[0065] 109-channel layer;
[0066] 110 - Barrier layer;
[0067] 111-Source;
[0068] 112-Drain;
[0069] 113-p-GaN layer;
[0070] 114 - Gate metal layer;
[0071] 115 - Passivation layer;
[0072] 116 - Anode metal interconnect layer;
[0073] 117 - Cathode metal interconnect layer;
[0074] 118 - Source metal interconnect layer;
[0075] 119 - Drain metal interconnect layer;
[0076] 120 - Anode field plate;
[0077] 121 - Drain field plate;
[0078] 122 - Gate field plate. Detailed Implementation
[0079] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0080] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0081] AlGaN / GaN HEMT, short for AlGaN / GaN high electron mobility transistor, is a semiconductor device based on an AlGaN / GaN heterostructure. Due to the polarization effect in AlGaN / GaN HEMT devices, a quantum potential well is formed at the heterojunction interface between AlGaN and GaN materials, generating a high-density, high-electron-mobility two-dimensional electron gas (2DEG). Therefore, compared to Si devices, AlGaN / GaN HEMT transistors have higher breakdown voltage, higher frequency response, and lower conduction losses.
[0082] GaN-based high electron mobility transistors and their power integrated circuits are candidates for next-generation ultra-high density power converters. They are already being used in AC adapters for high-density power supplies in consumer and data center applications, and also have significant advantages in motor drives.
[0083] However, unlike Si and SiC-based power devices, traditional GaN-HEMTs have almost zero avalanche breakdown characteristics. That is, when a large voltage or continuous high voltage stress is applied between the source and drain of a GaN HEMT device, the device is prone to punch-through, which leads to destructive breakdown and thus cannot meet the requirements of GaN HEMT devices in more industrial fields such as electric vehicles.
[0084] Therefore, the problem in the existing technology is how to protect GaN HEMT devices from destructive breakdown under the influence of high field in the source and drain.
[0085] In view of this, the inventors discovered through repeated experiments that, since the breakdown voltage of GaN-based pN junctions is slightly lower than that of GaN HEMT devices, by fabricating GaN HEMT devices based on GaN-based pN junction diodes and combining the GaN HEMT devices with GaN-based pN junction diodes, it can be ensured that the GaN-based pN junctions undergo avalanche breakdown first before the GaN HEMT devices break down, thereby achieving the effect of protecting the GaN HEMT devices from destructive breakdown.
[0086] Therefore, this invention proposes a novel structure that combines a GaN HEMT device with a GaN-based pN junction diode, solving the problem of how to protect the GaN HEMT device from destructive breakdown under high source-drain field conditions.
[0087] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.
[0088] Please refer to Figure 5 According to an embodiment of the present invention, a GaNHEMT device structure with anti-destructive breakdown function is provided, comprising:
[0089] A substrate 101, wherein a first nucleation layer 102 and a GaN buffer layer 103 are sequentially formed on the substrate 101 along a direction away from the substrate 101;
[0090] The pN diode includes a p+ doped region 105 and an N+ doped region 104 formed on a first region and a second region of the surface of the GaN buffer layer 103, respectively, and an anode 106 and a cathode 107 formed on the p+ doped region 105 and the N+ doped region 104, respectively; wherein the first region and the second region are opposite sides of the surface of the GaN buffer layer 103.
[0091] A GaN HEMT device is formed on the GaN buffer layer 103;
[0092] The breakdown voltage of the pN diode is lower than that of the GaN HEMT device.
[0093] The two opposite regions on the surface of the GaN buffer layer 103 are opposite sides in the horizontal direction within the plane of the paper, that is: the first region and the second region are two sides in the horizontal direction along the paper surface of the GaN buffer layer 103; wherein, the p+ doped region 105 is formed in the first region and the N+ doped region 104 is formed in the second region.
[0094] This invention provides a GaN HEMT device structure with anti-destructive breakdown function. By introducing a pN diode between the second nucleation layer 108 of a conventional GaN HEMT device and the GaN buffer layer at the bottom of the GaN HEMT device, since the breakdown voltage of the introduced pN diode is lower than that of the GaN HEMT device, when a large voltage or continuous high voltage stress is applied between the source 111 and drain 112 of the GaN HEMT device, the pN diode undergoes avalanche breakdown, thereby protecting the GaN HEMT device from destructive breakdown.
[0095] As can be seen, the technical solution provided by the present invention solves the problem of destructive breakdown of GaN HEMT devices when a large voltage or continuous high voltage stress is applied between the source 111 and drain 112 of a GaN HEMT device by introducing a pN diode with a breakdown voltage lower than that of a conventional GaN HEMT device; thereby achieving the effect of improving the performance of GaN HEMT devices.
[0096] In one embodiment, the pN diode further includes: an anode metal interconnect layer 116 and an anode field plate 120 formed at the top of the anode 106; and a cathode metal interconnect layer 117 formed at the top of the cathode 107;
[0097] The anode field plate 120 is formed at the top of the anode metal interconnect layer 116.
[0098] In one embodiment, the GaN HEMT device includes:
[0099] A second nucleation layer 108, a channel layer 109, and a barrier layer 110 are sequentially formed on the GaN buffer layer 103 in a direction away from the GaN buffer layer 103. In one specific embodiment, the first nucleation layer 102 and the second nucleation layer 108 are made of AlN, the channel layer 109 is made of GaN, and the barrier layer 110 is made of AlGaN. Of course, the aforementioned structural layers can also be made of other materials, and the present invention is not limited thereto. Any implementation of the material of the corresponding structural layer is within the protection scope of the present invention.
[0100] A source 111, a gate, and a drain 112 are formed on the barrier layer 110; wherein, the gate includes a p-GaN layer 113 and a gate metal layer 114 formed on the top of the p-GaN layer 113;
[0101] A source metal interconnect layer 118, a gate metal interconnect layer, and a drain metal interconnect layer 119 are respectively formed at the top of the source 111, the gate, and the drain 112; a passivation layer 115 is formed on the barrier layer 110 and fills the gaps between the source metal interconnect layer 118, the gate metal interconnect layer, and the drain metal interconnect layer 119; and
[0102] Gate field plate 122: The gate field plate 122 is formed on the passivation layer 115 at the top of the gate and is connected to the source metal interconnect layer 118.
[0103] In one embodiment, the GaN HEMT device structure with anti-damage breakdown structure function further includes: a drain field plate 121; the drain field plate 121 is formed on the passivation layer 115 between the drain metal interconnect layer 119 and the cathode metal interconnect layer 117 and connects the drain metal interconnect layer 119 and the cathode metal interconnect layer 117.
[0104] In one embodiment, the GaN HEMT device structure with anti-destructive breakdown structure function further includes:
[0105] A passivation layer 115 is formed on the GaN buffer layer 103 and fills the gaps between the source metal interconnect layer 118 and the anode metal interconnect layer 116, and between the drain metal interconnect layer 119 and the cathode metal interconnect layer 117. The passivation layer 115 described here is actually integrated with the passivation layer 115 described in GaN HEMT devices, which is formed on the barrier layer 110 and fills the gaps between the source metal interconnect layer 118, the gate metal interconnect layer, and the drain metal interconnect layer 119. This application distinguishes them for descriptive purposes.
[0106] Secondly, please refer to Figures 1-5 According to other embodiments of the present invention, a method for fabricating a GaN HEMT device structure with a destructive breakdown protection structure is also provided. A schematic flowchart of the method for fabricating a GaN HEMT device structure with a destructive breakdown protection structure is shown below. Figure 1 As shown, the method includes steps S11-S13, as detailed below:
[0107] S11: Provide a substrate 101;
[0108] S12: A first nucleation layer 102 and a GaN buffer layer 103 are sequentially formed on the substrate 101 in a direction away from the substrate 101; and
[0109] S13: Forming a pN diode and a GaN HEMT device; the pN diode is formed in a portion of the surface layer of the GaN buffer layer 103; wherein, the pN diode includes: a p+ doped region 105 and an N+ doped region 104 respectively formed in a first region and a second region of the surface layer of the GaN buffer layer 103, and an anode 106 and a cathode 107 respectively formed on the p+ doped region 105 and the N+ doped region 104; the GaN HEMT device is formed on the GaN buffer layer 103;
[0110] The breakdown voltage of the pN diode is lower than that of the GaN HEMT device. In one embodiment, the formation of the pN diode and GaN HEMT device in step S13 specifically includes steps S131-S136, as follows:
[0111] S131: P+ ions and N+ ions are implanted in the first region and the second region respectively, and the p+ ions and N+ ions are activated to form the p+ doped region 105 and the N+ doped region 104; specifically, p+ ions are implanted in the first region to form the p+ doped region 105; N+ ions are implanted in the second region to form the N+ doped region 104, and the p+ ions are activated to form N+ ions; the device after forming the p+ doped region 105 and the N+ doped region 104 is as follows: Figure 2 As shown;
[0112] S132: A second nucleation layer 108, a channel layer 109, a barrier layer 110, and a p-GaN layer 113 are sequentially formed on the GaN buffer layer 103 in a direction away from the GaN buffer layer 103 and mesa isolation is performed; the p-GaN layer 113 covers part of the surface of the barrier layer 110.
[0113] S133: Forming a source 111, a drain 112, an anode 106, and a cathode 107; the anode 106 and the cathode 107 are formed on the GaN buffer layer 103 on both sides of the GaN HEMT device along the first direction; the source 111 and the drain 112 are formed on the barrier layer 110 on both sides of the p-GaN layer 113 along the first direction; the first direction is the horizontal direction of the plane of the paper.
[0114] Specifically, step S133, forming the source 111, drain 112, anode 106, and cathode 107, involves depositing metal materials on the barrier layer 110 and the GaN buffer layer 103, respectively, and annealing them to form the source 111, drain 112, anode 106, and cathode 107. The device after forming the source 111, drain 112, anode 106, and cathode 107 is as follows: Figure 3 As shown;
[0115] S134: Forming a gate; the gate includes the p-GaN layer 113 and a gate metal layer 114; the gate metal layer 114 is formed on top of the p-GaN layer 113; the device after forming the gate is as follows: Figure 4 As shown;
[0116] S135: Deposit a passivation layer 115 at the top of the gate;
[0117] In this application, the pN diode further includes an anode metal interconnect layer 116 and an anode field plate 120 and a cathode metal interconnect layer 117 at its top; the anode metal interconnect layer 116 and the cathode metal interconnect layer 117 are respectively formed at the top of the anode 106 and the cathode 107;
[0118] The GaN HEMT device structure with anti-damage breakdown structure function also includes: a drain field plate 121; the drain field plate 121 is formed on the passivation layer 115 between the drain 112 and the cathode 107 and connects the drain metal interconnect layer 119 and the cathode metal interconnect layer 117.
[0119] Therefore, the fabrication methods for GaN HEMT device structures with anti-destructive breakdown structure functions also include:
[0120] S136: A source metal interconnect layer 118, a drain metal interconnect layer 119, a gate metal interconnect layer, an anode metal interconnect layer 116, and a cathode metal interconnect layer 117 are formed at the top ends of the source 111, the drain 112, the gate, the anode 106, and the cathode 107, respectively; and
[0121] A gate field plate 122, an anode field plate 120, and a drain field plate 121 are formed. A source metal interconnect layer 118, a drain metal interconnect layer 119, a gate metal interconnect layer, an anode metal interconnect layer 116, and a cathode metal interconnect layer 117 are formed.
[0122] Among them, the device formed after the gate field plate 122, the anode field plate 120 and the drain field plate 121 are as follows: Figure 5 As shown.
[0123] Specifically, step S132, which involves sequentially forming a second nucleation layer 108, a channel layer 109, a barrier layer 110, and a p-GaN layer 113 on the GaN buffer layer 103 along a direction away from the GaN buffer layer 103 and performing mesa isolation, includes steps S1321-S1325, as follows:
[0124] S1321: A second nucleation layer 108, a channel layer 109, a barrier layer 110, and a p-GaN layer 113 are sequentially epitaxially on the GaN buffer layer 103 in a direction away from the GaN buffer layer 103.
[0125] S1322: Etch the two ends of the second nucleation layer 108, the channel layer 109, the barrier layer 110, and the p-GaN layer 113 along the first direction to achieve the mesa isolation.
[0126] S1323: Photoresist is coated on the GaN buffer layer 103 and the p-GaN layer 113, and the photoresist is exposed and developed to form a patterned photoresist.
[0127] S1324: Etch the p-GaN layer 113 on both sides along the first direction using the patterned photoresist as a mask;
[0128] S1325: Remove the patterned photoresist to form the p-GaN layer 113 covering a portion of the barrier layer 110;
[0129] Second nucleation layer 108 channel layer 109 barrier layer 110p-GaN layer 113
[0130] In one embodiment, forming the gate in step S134 includes steps S1341-S1343, as follows:
[0131] S1341: Deposit passivation layer 115; the passivation layer 115 is formed on the barrier layer 110 and the GaN buffer layer 103 and fills the gap between the source 111, the drain 112, the cathode 107 and the anode 106;
[0132] S1342: Etch the passivation layer 115 at the top of the p-GaN layer 113 to form a gate cavity;
[0133] S1343: Deposit the gate metal layer 114 in the gate cavity to form the gate.
[0134] In step S136, a source metal interconnect layer 118, a drain metal interconnect layer 119, a gate metal interconnect layer, an anode metal interconnect layer 116, and a cathode metal interconnect layer 117 are formed at the top of the source 111, the drain 112, the gate, the anode 106, and the cathode 107, respectively; and a gate field plate 122, an anode field plate 120, and a drain field plate 121 are formed, specifically including:
[0135] S1361: Etch the passivation layer 115 at the top of the source 111, the drain 112, the gate, the anode 106 and the cathode 107 to form a source cavity, a drain cavity, a gate cavity, an anode cavity and a cathode cavity.
[0136] S1362: Deposit metal materials in the source cavity, drain cavity, gate cavity, anode cavity, and cathode cavity to form a source metal interconnect layer 118, a drain metal interconnect layer 119, a gate metal interconnect layer, anode metal interconnect layer 116, and a cathode metal interconnect layer 117, respectively; and deposit metal materials on the passivation layer 115 at the top of the gate, on the surface of the passivation layer 115 between the drain metal interconnect layer 119 and the cathode metal interconnect layer 117, and at the top of the source metal interconnect layer 118 to form a gate field plate 122, a drain field plate 121, and an anode field plate 120, respectively.
[0137] Furthermore, according to another embodiment of the present invention, an electronic device is also provided, comprising a GaN HEMT device structure having a destructive breakdown structure function as described in any of the first aspects of the present invention.
[0138] According to other embodiments of the present invention, a method for manufacturing an electronic device is also provided, including a method for manufacturing a GaN HEMT device structure with anti-destructive breakdown structure function as described in any of the second aspects of the present invention.
[0139] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A GaN HEMT device structure with anti-destructive breakdown function, characterized in that, include: A substrate, wherein a first nucleation layer and a GaN buffer layer are sequentially formed on the substrate in a direction away from the substrate; a pN diode comprising a p + doped region and an N + doped region, and an anode and a cathode formed on the p + doped region and an N + doped region, respectively; wherein the first region and the second region are regions on opposite sides along the surface of the GaN buffer layer; GaN HEMT devices are formed on the GaN buffer layer; The breakdown voltage of the pN diode is lower than that of the GaN HEMT device. An anode metal interconnect layer and an anode field plate are formed at the top of the anode; and a cathode metal interconnect layer is formed at the top of the cathode; wherein the anode field plate is formed at the top of the anode metal interconnect layer; A second nucleation layer, a channel layer, and a barrier layer are sequentially formed on the GaN buffer layer in a direction away from the GaN buffer layer; The source, gate, and drain are formed on the barrier layer; Source metal interconnect layer, gate metal interconnect layer and drain metal interconnect layer are respectively formed at the top of the source, the gate and the drain; A passivation layer formed on the GaN buffer layer and filling the gaps between the source metal interconnect layer and the anode metal interconnect layer, and between the drain metal interconnect layer and the cathode metal interconnect layer; A passivation layer formed on the barrier layer and filling the gaps between the source metal interconnect layer, the gate metal interconnect layer, and the drain metal interconnect layer; Drain field plate; the drain field plate is formed on the passivation layer between the drain metal interconnect layer and the cathode metal interconnect layer and connects the drain metal interconnect layer and the cathode metal interconnect layer; Gate field plate: The gate field plate is formed on the passivation layer at the top of the gate and is connected to the source metal interconnect layer.
2. The GaN HEMT device structure with anti-destructive breakdown function according to claim 1, characterized in that, The GaN HEMT device includes: The gate includes a p-GaN layer and a gate metal layer formed on top of the p-GaN layer.
3. The GaN HEMT device structure with anti-destructive breakdown function according to claim 1, characterized in that, The first nucleation layer and the second nucleation layer are made of AlN, the channel layer is made of GaN, and the barrier layer is made of AlGaN.
4. A method for fabricating a GaN HEMT device structure with a destructive breakdown protection function, used to form the GaN HEMT device structure as described in any one of claims 1-3, characterized in that, include: Provide a substrate; A first nucleation layer and a GaN buffer layer are sequentially formed on the substrate in a direction away from the substrate; as well as Forming pN diodes and GaN HEMT devices; The pN diode is formed in the surface layer of the GaN buffer layer; The pN diode includes: pN diodes formed in a first region and a second region on the surface of the GaN buffer layer, respectively. + Doped regions and N + Doped regions, and respectively formed in the p + The doped region and the N + Anode and cathode on the doped region; The GaN HEMT device is formed on a portion of the GaN buffer layer; The breakdown voltage of the pN diode is lower than the breakdown voltage of the GaN HEMT device.
5. The method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function according to claim 4, characterized in that, The specific steps for forming pN diodes and GaN HEMT devices include: inject p into the first region and the second region respectively. + Ions and N + Ions and activate the p + Ions and the N + Ions to form the p + The doped region and the N + Doped regions; A second nucleation layer, a channel layer, a barrier layer, and a p-GaN layer are sequentially formed on the GaN buffer layer in a direction away from the GaN buffer layer and are then mesa-isolated; the p-GaN layer covers a portion of the surface of the barrier layer. A source, a drain, an anode, and a cathode are formed; the anode and the cathode are formed on the GaN buffer layer on both sides of the GaN HEMT device along a first direction; the source and the drain are formed on the barrier layer on both sides of the p-GaN layer along the first direction. A gate is formed; the gate includes the p-GaN layer and a gate metal layer; the gate metal layer is formed on top of the p-GaN layer; A passivation layer is deposited at the top of the gate; A source metal interconnect layer, a drain metal interconnect layer, a gate metal interconnect layer, an anode metal interconnect layer, and a cathode metal interconnect layer are formed at the top of the source, the drain, the gate, the anode, and the cathode, respectively; and a gate field plate, an anode field plate, and a drain field plate are formed.
6. The method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function according to claim 5, characterized in that, The formation of a second nucleation layer, a channel layer, a barrier layer, and a p-GaN layer sequentially on the GaN buffer layer along a direction away from the GaN buffer layer, and the implementation of mesa isolation, specifically includes: The second nucleation layer, the channel layer, the barrier layer, and the p-GaN layer are sequentially epitaxially on the GaN buffer layer in a direction away from the GaN buffer layer; The mesa isolation is achieved by etching the second nucleation layer, the channel layer, the barrier layer, and both ends of the p-GaN layer along the first direction, thereby exposing part of the GaN buffer layer; Photoresist is coated on the exposed GaN buffer layer and the p-GaN layer, and the photoresist is exposed and developed to form a patterned photoresist. Using the patterned photoresist as a mask, the p-GaN layer is etched on both sides of the p-GaN layer along the first direction to expose a portion of the barrier layer; Remove the patterned photoresist to form the p-GaN layer covering a portion of the barrier layer.
7. The method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure function according to claim 6, characterized in that, Forming the gate specifically includes: A passivation layer is deposited; the passivation layer is formed on the barrier layer and the GaN buffer layer and fills the voids between the source, the drain, the cathode and the anode; The passivation layer at the top of the p-GaN layer is etched to form a gate cavity; The gate metal layer is deposited in the gate cavity to form the gate.
8. An electronic device, characterized in that, The GaN HEMT device structure with anti-destructive breakdown structure function as described in any one of claims 1-3 is included.
9. A method for manufacturing an electronic device, characterized in that, The method for fabricating a GaN HEMT device structure with anti-destructive breakdown structure as described in any one of claims 4 to 7.