WO2024060740A1 - 一种igbt器件 - Google Patents

一种igbt器件 Download PDF

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Publication number
WO2024060740A1
WO2024060740A1 PCT/CN2023/102567 CN2023102567W WO2024060740A1 WO 2024060740 A1 WO2024060740 A1 WO 2024060740A1 CN 2023102567 W CN2023102567 W CN 2023102567W WO 2024060740 A1 WO2024060740 A1 WO 2024060740A1
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Prior art keywords
electric field
layer
transition layer
igbt device
doping
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PCT/CN2023/102567
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English (en)
French (fr)
Inventor
祁金伟
刘倩
张耀辉
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Suzhou Watech Electronics Co Ltd
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Suzhou Watech Electronics Co Ltd
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Priority to EP23867035.0A priority Critical patent/EP4593085A4/en
Publication of WO2024060740A1 publication Critical patent/WO2024060740A1/zh
Anticipated expiration legal-status Critical
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D62/00—Semiconductor bodies, or regions thereof, of devices having potential barriers
    • H10D62/10—Shapes, relative sizes or dispositions of the regions of the semiconductor bodies; Shapes of the semiconductor bodies
    • H10D62/124—Shapes, relative sizes or dispositions of the regions of semiconductor bodies or of junctions between the regions
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
    • H10D12/01—Manufacture or treatment
    • H10D12/031—Manufacture or treatment of IGBTs
    • H10D12/032—Manufacture or treatment of IGBTs of vertical IGBTs
    • H10D12/038—Manufacture or treatment of IGBTs of vertical IGBTs having a recessed gate, e.g. trench-gate IGBTs
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
    • H10D12/411—Insulated-gate bipolar transistors [IGBT]
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
    • H10D12/411—Insulated-gate bipolar transistors [IGBT]
    • H10D12/418—Insulated-gate bipolar transistors [IGBT] having a drift region having a doping concentration that is higher at the emitter side relative to other parts of the drift region
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
    • H10D12/411—Insulated-gate bipolar transistors [IGBT]
    • H10D12/441—Vertical IGBTs
    • H10D12/461—Vertical IGBTs having non-planar surfaces, e.g. having trenches, recesses or pillars in the surfaces of the emitter, base or collector regions
    • H10D12/481—Vertical IGBTs having non-planar surfaces, e.g. having trenches, recesses or pillars in the surfaces of the emitter, base or collector regions having gate structures on slanted surfaces, on vertical surfaces, or in grooves, e.g. trench gate IGBTs
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D62/00—Semiconductor bodies, or regions thereof, of devices having potential barriers
    • H10D62/01—Manufacture or treatment
    • H10D62/051—Forming charge compensation regions, e.g. superjunctions
    • H10D62/058—Forming charge compensation regions, e.g. superjunctions by using trenches, e.g. implanting into sidewalls of trenches or refilling trenches
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
    • H10D62/00—Semiconductor bodies, or regions thereof, of devices having potential barriers
    • H10D62/10—Shapes, relative sizes or dispositions of the regions of the semiconductor bodies; Shapes of the semiconductor bodies
    • H10D62/102—Constructional design considerations for preventing surface leakage or controlling electric field concentration
    • H10D62/103—Constructional design considerations for preventing surface leakage or controlling electric field concentration for increasing or controlling the breakdown voltage of reverse-biased devices
    • H10D62/105—Constructional design considerations for preventing surface leakage or controlling electric field concentration for increasing or controlling the breakdown voltage of reverse-biased devices by having particular doping profiles, shapes or arrangements of PN junctions; by having supplementary regions, e.g. junction termination extension [JTE] 
    • H10D62/109—Reduced surface field [RESURF] PN junction structures
    • H10D62/111—Multiple RESURF structures, e.g. double RESURF or 3D-RESURF structures
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Definitions

  • the present application relates to the technical field of power devices, specifically, to an IGBT device.
  • IGBT Insulated Gate Bipolar Transistor
  • BJT bipolar junction transistor
  • MOS insulated gate field effect transistor
  • MOSFET metal-oxide-semiconductor field-effect transistor
  • GTR giant transistor
  • Super Junction technology provides new technical means to improve the performance of power devices. Utilizing the staggered arrangement of N-type and P-type regions, the super junction structure can flatten and regulate the electric field in the drift region, effectively reducing the thickness of the drift region of power devices to achieve the purpose of increasing the breakdown voltage of the device.
  • the traditional SJ-IGBT device is shown in Figure 1.
  • 1 is the P-collector region
  • 2 is the N-drift region
  • 3 is the P-type super junction region
  • 4 is the N-type second epitaxy
  • 5 is the gate oxide layer.
  • 6 is the gate
  • 7 is the Pwell
  • 8 is the N+ emitter
  • 9 is the dielectric layer
  • 10 is the emitter metal
  • 11 is the P+ collector
  • 12 is the collector metal.
  • the part of the N-drift region 2 located below the P-type super-junction region will store a large number of holes, causing tail current, and the tail current will cause large turn-off losses.
  • Figure 2 is a schematic diagram of the electric field changes caused by applying different voltages to the emitter and collector when the same traditional SJ-IGBT device shown in Figure 1 is turned off.
  • the vertical axis is the distance from Pwell7 to N-drift region 2 in Figure 1
  • the horizontal axis is the actual result formed by applying different voltages to the emitter and collector of the traditional SJ-IGBT device when it is turned off.
  • the strength of the international electric field When the traditional SJ-IGBT device is turned off, when a lower voltage such as 200V is applied to the emitter and collector, the electric field terminates in the N-drift region 2, and the dotted line position is the position where the electric field terminates.
  • SJ-IGBT devices as a new generation of high-speed IGBT devices, have better device merit.
  • Lower conduction voltage drop, lower switching loss, and higher switching speed make the device of great application value, and its excellent electrical performance has been experimentally verified.
  • Embodiments of the present application provide an IGBT device to solve the technical problems of traditional SJ-IGBT devices with large turn-off loss during the turn-off process and insufficient device stability caused by sudden changes in the electric field.
  • the embodiment of the present application provides an IGBT device, including:
  • the doping concentration of the electric field transition layer is less than the doping concentration of the electric field termination layer, and the drift region and the electric field transition layer can respectively accumulate minority carriers by conductivity modulation effect; when the IGBT device is turned off, the electric field transition layer is completely depleted, the electric field is reduced in the electric field transition layer and reduced to 0 in the electric field termination layer, and the electric field decreases smoothly from top to bottom at the junction of the electric field transition layer and the electric field termination layer.
  • the doping concentration of the electric field transition layer is less than the doping concentration of the electric field termination layer, and only two of the three layers, the drift region, the electric field transition layer, and the electric field termination layer, can produce conductance modulation effects and accumulate minority currents. carriers, but the electric field termination layer cannot produce conductance modulation effect and cannot accumulate minority carriers; that is, the doping concentration of the electric field transition layer is low, and the doping concentration is low enough to produce conductance modulation effect and accumulate minority carriers; the electric field termination layer
  • the doping concentration is high, and the doping concentration is so high that there is almost no conductance modulation effect and no accumulation of minority carriers.
  • the conductance modulation effect occurs in the drift region and the electric field transition layer, reducing the resistance of the drift region and the electric field transition layer, making the IGBT When the device is turned on, it has a low on-state voltage. That is, the resistance of the drift region and the electric field transition layer is reduced through the conductance modulation effect. Due to the existence of the conductance modulation effect, when the IGBT device is turned on, the collector injects a large number of minority carriers into the drift region and the electric field transition layer for accumulation.
  • the electric field transition layer When the IGBT device is turned off, the electric field rapidly broadens downward, and the minority carriers stored in the drift region and the electric field transition layer are quickly depleted, that is, the electric field transition layer is completely depleted; while the electric field termination layer has a relatively high doping concentration. High, almost no minority carriers are stored, so the tail current becomes very small.
  • the thickness of the electric field transition layer In order to completely deplete the minority carriers accumulated in the electric field transition layer as soon as possible, the thickness of the electric field transition layer needs to be set smaller. Because the thickness of the electric field transition layer is small, the number of minority carriers accumulated in the electric field transition layer will be smaller and can be depleted in the electric field transition layer in a shorter period of time.
  • the electric field decreases smoothly from top to bottom at the interface between the electric field transition layer and the electric field termination layer, preventing sudden changes in the electric field at the interface between the electric field transition layer and the electric field termination layer, making the IGBT device more stable.
  • Figure 1 is a schematic structural diagram of a traditional SJ-IGBT device in the background technology
  • Figure 2 is a schematic diagram of the electric field changes formed by different voltages at the emitter and collector when the same traditional SJ-IGBT device shown in Figure 1 is turned off;
  • FIG. 3 is a schematic structural diagram of an IGBT device according to an embodiment of the present application.
  • Figure 4 is a schematic diagram of the electric field changes formed by different voltages at the emitter and collector when the IGBT device shown in Figure 3 has an electric field that smoothly decreases from top to bottom at the interface between the electric field transition layer and the electric field termination layer.
  • P-collector region 1 N-drift region 2, P-type super junction region 3, second epitaxy 4, gate oxide layer 5, gate 6, Pwell 7, N+ emitter 8, dielectric layer 9, emitter metal 10 , P+ collector 11, collector metal 12;
  • Electric field transition layer 1 drift region 2, pillar region 3, second doping type epitaxial layer 4, gate oxide layer 5, gate electrode 6, well region 7, emitter 8, dielectric layer 9, emitter metal 10, electric field Termination layer 11, collector 12, collector metal 13.
  • the IGBT device includes:
  • a well region 7 of a first doping type is formed above the drift region
  • the doping concentration of the electric field transition layer ⁇ the doping concentration of the electric field termination layer, the drift region and the electric field transition layer can respectively produce conductance modulation effects and accumulate minority carriers; when the IGBT device is turned off, the electric field transition layer is completely depleted , the electric field decreases at the electric field transition layer and decreases to 0 at the electric field termination layer, and the electric field decreases smoothly from top to bottom at the interface between the electric field transition layer and the electric field termination layer.
  • the doping concentration of the electric field transition layer is less than the doping concentration of the electric field termination layer, and only two of the three layers of the drift region, electric field transition layer, and electric field termination layer, the drift region and the electric field transition layer can respectively
  • the conductance modulation effect occurs and minority carriers are accumulated, but the conductance modulation effect cannot occur in the electric field termination layer and minority carriers cannot accumulate; that is, the doping concentration of the electric field transition layer is low, and the doping concentration is low enough to allow the conductance modulation effect to accumulate minority carriers.
  • Carriers the doping concentration of the electric field termination layer is high, and the doping concentration is so high that almost no conductance modulation effect will occur and minority carriers will not accumulate.
  • the conductance modulation effect occurs in the drift region and the electric field transition layer, reducing the resistance of the drift region and the electric field transition layer, making the IGBT When the device is turned on, it has a low on-state voltage. That is, the resistance of the drift region and the electric field transition layer is reduced through the conductance modulation effect. Due to the existence of the conductance modulation effect, when the IGBT device is turned on, the collector injects a large number of minority carriers into the drift region and the electric field transition layer for accumulation.
  • the electric field transition layer When the IGBT device is turned off, the electric field rapidly broadens downward, and the minority carriers stored in the drift region and the electric field transition layer are quickly depleted, that is, the electric field transition layer is completely depleted; while the electric field termination layer has a relatively high doping concentration. High, almost no minority carriers are stored, so the tail current becomes very small.
  • the thickness of the electric field transition layer In order to completely deplete the minority carriers accumulated in the electric field transition layer as soon as possible, the thickness of the electric field transition layer needs to be set smaller. Because the thickness of the electric field transition layer is smaller, the number of minority carriers accumulated in the electric field transition layer will be smaller and can be depleted in the electric field transition layer in a shorter period of time.
  • the electric field decreases smoothly from top to bottom at the interface between the electric field transition layer and the electric field termination layer, preventing sudden changes in the electric field at the interface between the electric field transition layer and the electric field termination layer, making the IGBT device more stable.
  • the rate of electric field decrease corresponds to the rate of change of current when the IGBT device is turned off. The faster the electric field decreases, the greater the rate of change of current, that is, the greater the rate of change of current di/dt, resulting in a larger overshoot voltage of the device, which may cause damage to the device. .
  • the electric field decreases smoothly from top to bottom at the interface between the electric field transition layer and the electric field termination layer.
  • the smooth decrease is quantified and expressed as follows:
  • the slope of the electric field on the lower surface of the electric field transition layer T , the lower surface of the transition layer , and the slope of the electric field on the upper surface of the electric field termination layer, T on the upper surface of the termination layer satisfy the following relationship: (T stop layer upper surface - T transition layer lower surface )/T stop layer upper surface ⁇ 10%.
  • the electric field decreases slowly in the electric field transition layer and decreases rapidly in the electric field termination layer. Therefore, the interface between the electric field transition layer and the electric field termination layer is the location where a large change in the electric field occurs. Therefore, by controlling the change of the electric field at the interface between the electric field transition layer and the electric field termination layer, the electric field at the interface between the electric field transition layer and the electric field termination layer does not suddenly change, but decreases smoothly.
  • the doping concentration at the interface between the electric field transition layer and the electric field termination layer is controlled.
  • the doping concentration R of the lower surface of the electric field transition layer , the lower surface of the transition layer , and the doping concentration R of the upper surface of the electric field termination layer , the lower surface of the termination layer satisfy the following relationship: ( Upper surface of R termination layer - Lower surface of R transition layer )/ Upper surface of R termination layer ⁇ 10%.
  • the difference in doping concentration between the lower surface of the electric field transition layer and the lower surface of the electric field termination layer is smaller.
  • the doping concentration of the electric field transition layer gradually increases from the upper surface to the lower surface of the electric field transition layer.
  • the doping concentration of the electric field transition layer gradually increases from the upper surface to the lower surface of the electric field transition layer, and the doping of the electric field transition layer is a linear change doping.
  • the doping concentration of the electric field transition layer gradually increases from the upper surface to the lower surface of the electric field transition layer, and the doping of the electric field transition layer has a half-normal distribution.
  • the normal distribution curve is bell-shaped, low at both ends, high in the middle, and symmetrical.
  • the curve of a half-normal distribution is half of the normal distribution.
  • the doping concentration of the electric field transition layer has an increasing slope from the upper surface of the electric field transition layer to the lower surface, and reaches a maximum slope at the lower surface of the electric field transition layer.
  • the doping concentration within the electric field transition layer increases smoothly, and the doping concentration at the interface between the lower surface of the electric field transition layer and the upper surface of the electric field termination layer also increases smoothly.
  • the total charge Q of the electric field transition layer is always less than or equal to k% ⁇ Ec/ ⁇ s;
  • k% is the percentage of the electric field strength under the minimum preset operating voltage condition of the IGBT device to the critical breakdown electric field strength
  • Ec is the critical breakdown field strength of the Si substrate of the IGBT device
  • ⁇ s is the dielectric constant of the Si substrate of the IGBT device.
  • the total charge Q of the electric field transition layer needs to meet the preset condition that Q is always less than k% ⁇ Ec/ ⁇ s, and can pass through a short period of time in the electric field transition layer. Time runs out. Therefore, no tail current will be generated, resulting in smaller turn-off energy loss of the IGBT device.
  • the value range of k% is greater than or equal to 10% and less than or equal to 80%.
  • the first doping type is N-type doping
  • the second doping type is P-type doping.
  • the minority carriers are electrons.
  • the first doping type is P-type doping; the second doping type is N-type doping.
  • the minority carriers are holes.
  • the IGBT device of the embodiment of the present application is particularly suitable for the case where the first doping type is P-type doping and the second doping type is N-type doping.
  • the electric field transition layer 1 is N-type lightly doped
  • the electric field termination layer 11 is N-type heavily doped
  • the drift region 2 is N-type lightly doped
  • epitaxial layer 4 is N-type lightly doped
  • emitter 8 is N-type heavily doped
  • collector 12 is P-type heavily doped.
  • q is the charge of a single electron
  • G is the slope of linearly changing doping
  • ⁇ s is the dielectric constant of Si
  • d(x) is the distance between the upper surface and the lower surface of the electric field transition layer along the direction of the electric field intensity.
  • Formula 1 is a universal formula for the electric field intensity and total charge of the electric field transition layer.
  • the present application aims to realize that when the IGBT device is turned off under different voltage conditions, the current tail is very small or even does not exist.
  • the minimum preset operating voltage of the IGBT device is k% ⁇ BV
  • BV is the breakdown voltage of the IGBT device
  • the maximum field strength Em corresponding to the minimum preset operating voltage of the IGBT device is approximately k% ⁇ Ec
  • k% is the percentage of the electric field strength under the minimum preset operating voltage of the IGBT device to the critical breakdown electric field strength, that is, the electric field strength on the upper surface of the transition layer is k% ⁇ Ec
  • Ec is the critical breakdown field strength of Si
  • ⁇ s is the dielectric constant of Si.
  • the critical condition is that the electric field strength on the lower surface of the electric field transition layer is equal to 0, and correspondingly, the total charge Q of the electric field transition layer under the critical condition is critical .
  • the critical condition is that the electric field strength on the lower surface of the electric field transition layer is equal to 0
  • the total charge Q of the electric field transition layer should be less than the Q critical , that is, Q total ⁇ k% ⁇ Ec/ ⁇ s.
  • Qtotal ⁇ k% The applicable relational expression for the total amount, in this particular case, is not only applicable when the doping of the electric field transition layer is uniformly doped, but also when the doping of the electric field transition layer is non-uniformly doped. . So far, in the specific case where the minimum preset operating voltage of the IGBT device is k% ⁇ BV and the critical condition is that the electric field intensity on the lower surface of the electric field transition layer is equal to 0, the requirements for the total charge Qtotal of the electric field transition layer have been determined.
  • the lower end of the pillar area 3 is flush with the lower end of the drift area 2 , and the lower end of the pillar area 3 and the lower end of the drift area 2 are respectively connected to the upper surface of the electric field transition layer 1 .
  • the IGBT device also includes:
  • a second doping type epitaxial layer 4 is formed above the drift region 2 and located below the well region 7;
  • the upper end of the pillar area 3 is flush with the upper end of the drift area 2 , and the upper end of the pillar area 3 and the upper end of the drift area 2 are respectively connected to the lower surface of the epitaxial layer 4 .
  • the upper end, lower end, left end and right end of the column area 3 are all second doping type areas, that is, the column area 3 is floating.
  • the column area is floating, more minority carriers injected by the collector into the column area will be stored, so that the on-state voltage drop in the on state is lower.
  • the IGBT device also includes:
  • Collector metal 13 is formed under the collector 12
  • the gate trench extends downward from the upper surface of the well region 7 into the epitaxial layer 4;
  • a gate oxide layer 5 is formed in the gate trench
  • the gate electrode 6 is formed on the gate oxide layer 5 , and the upper surfaces of the gate electrode and the well region 7 flush; flush;
  • An emitter electrode 8 of the second doping type extends downward from the upper surface of the well region 7, and the depth of the emitter electrode 8 is shallower than that of the well region 7;
  • Dielectric layer 9 covering the gate electrode and gate oxide layer and partially covering the emitter electrode 8;
  • the emitter metal 10 is formed on the emitter 8 and the dielectric layer 9 ; wherein the dielectric layer 9 is used to insulate the gate and the emitter metal 10 .
  • the IGBT device is a super junction IGBT device with a trench gate.
  • Figure 4 is a schematic diagram of the electric field changes formed by the different voltages of the emitter and collector when the IGBT device is turned off when the electric field decreases smoothly from top to bottom at the interface between the electric field transition layer and the electric field termination layer shown in Figure 3.
  • the vertical axis is In Figure 3, the distance from well region 7 to drift region 2, the horizontal axis is the actual electric field distribution of the emitter and collector as the voltage increases when the IGBT device shown in Figure 3 is turned off.
  • the electric field transition layer is thin. From the electric field distribution, it can be seen that the electric field of the same device under different voltage conditions eventually terminates at the electric field termination layer, as shown in Figure 4. Therefore, no matter under which voltage condition the IGBT device is turned off, the current tail will be very small or even non-existent.
  • the electric field is cut off at different positions in the drift region under different voltage conditions, as shown in Figure 2.
  • the voltage is small, the undepleted drift region is wider, so the undepleted drift region will cause current tailing when turned off.
  • the higher the voltage the smaller the current tail. Therefore, compared with the traditional super junction structure, the IGBT device of the embodiment of the present application can be used at both high voltage and low voltage, and even under low voltage conditions, there is no tail current and the turn-off loss is small.
  • the doping concentration of the electric field termination layer is 10 17 /cm 3 to 5 ⁇ 10 17 /cm 3 , that is, the doping concentration of the electric field termination layer is high enough, and the electric field termination layer will not have a conductivity modulation effect, that is, there will be no
  • the electric field termination layer only plays the role of accumulating minority carriers and linearly reducing the electric field to zero in the electric field termination layer to achieve the termination of the electric field. That is, the electric field termination layer only plays the role of quickly terminating the electric field.
  • the doping concentration of the electric field transition layer is on the order of 10 13 /cm 3 to 10 15 /cm 3 . Therefore, the electric field transition layer will have a conductance modulation effect and can also withstand part of the breakdown voltage.
  • the electric field terminates in the electric field termination layer, and there is a preset distance between the position where the electric field terminates in the electric field termination layer and the lower surface of the electric field termination layer to prevent breakdown.
  • the thickness of the electric field transition layer ⁇ the thickness of the electric field termination layer.
  • the thickness of the electric field transition layer is required to be thin.
  • the thickness of the electric field termination layer needs to prevent breakdown, so the required thickness is relatively large. Therefore, the thickness of the electric field transition layer is less than the thickness of the electric field termination layer.
  • the doping concentration of the electric field transition layer is at least 1-1.5 orders of magnitude lower than the doping concentration of the electric field termination layer.
  • the doping concentration of the epitaxial layer ⁇ the doping concentration of the drift region, and the doping concentration of the epitaxial layer is slightly lower than that of the drift region.
  • the doping concentration of the drift region is on the order of 10 14 /cm 3 to 10 15 /cm 3
  • the doping concentration of the column region and the doping concentration of the drift region are on the same order of magnitude
  • the charges in the drift region and the column region are The amounts should be equal.
  • the charge balance must be achieved in the drift region and column region.
  • Step S11 grow the first epitaxy on the silicon substrate
  • Step S12 Dig the deep groove corresponding to the column area and fill the deep groove corresponding to the column area;
  • Step S13 grow the second epitaxy
  • Step S14 Dig a trench corresponding to the gate, grow a gate oxide layer in the trench corresponding to the gate, and Place polysilicon on top of the chemical layer and smooth it, and the gate is now completed;
  • Step S15 Perform ion implantation or thermal diffusion on the upper surface of the second epitaxy to form a well region 7.
  • the depth of the well region 7 is shallower than the trench corresponding to the gate electrode;
  • Step S16 Perform ion implantation or thermal diffusion on the upper surface of the second epitaxy to form the emitter 8.
  • the depth of the emitter 8 is shallower than the well region 7;
  • Step S17 Form dielectric layer 9;
  • Step S18 forming the emitter metal 10.
  • the device is turned over and ions are implanted on the back side to form the collector electrode 12 and the collector metal 13 .
  • the IGBT device of the second embodiment also has the following characteristics.
  • the preset operating voltage of the IGBT device is greater than or equal to 10% ⁇ BV and less than or equal to 80% ⁇ BV, and BV is the breakdown voltage of the IGBT device.
  • the preset operating voltage of the IGBT device is greater than or equal to 10% ⁇ BV and less than or equal to 80% ⁇ BV, that is, the preset operating voltage of the IGBT device has a wide range.
  • the reason why the preset operating voltage range of the IGBT device in the embodiment of the present application is very wide is that when the actual operating voltage of the IGBT device is within the preset operating voltage range, whether it is high voltage or low voltage, when it is turned off, the electric field is It can quickly broaden downward, and the minority carriers stored in the drift region and the electric field transition layer are quickly depleted, that is, the electric field transition layer can be completely depleted; while the electric field termination layer has almost no storage due to its high doping concentration.
  • the IGBT device of the embodiment of the present application realizes that the tail current is no longer related to the actual operating voltage.
  • the size of the tail current is related to the actual operating voltage of the super junction device. The smaller the actual operating voltage, the greater the tail current. Therefore, compared with the traditional super junction structure, the IGBT device of the embodiment of the present application can be used at high voltage within the preset operating voltage range, and can be used at low voltage within the preset operating voltage range, and even under low voltage conditions, also There is no tail current and the turn-off loss is small.
  • the preset operating voltage of the IGBT device is greater than or equal to 10% ⁇ BV and less than or equal to 80% ⁇ BV, that is, the minimum preset operating voltage of the IGBT device is 10% ⁇ BV, and the maximum preset operating voltage of the IGBT device is 80%. ⁇ BV.
  • the preferred value range of the preset operating voltage of the IGBT device is greater than or equal to 60% ⁇ BV and less than or equal to 70% ⁇ BV.
  • the actual working voltage of the IGBT device is greater than or equal to 60% ⁇ BV and less than or equal to 70% ⁇ BV.
  • the working state of the IGBT device is relatively stable.
  • first and second are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as “first” and “second” may explicitly or implicitly include one or more of these features.
  • “plurality” means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.
  • connection should be understood in a broad sense; taking connection as an example, it can be directly connected, or it can be indirectly connected through an intermediary, or it can be two The connection within an element or the interaction between two elements.
  • connection should be understood in a broad sense; taking connection as an example, it can be directly connected, or it can be indirectly connected through an intermediary, or it can be two The connection within an element or the interaction between two elements.

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  • Electrodes Of Semiconductors (AREA)
  • Insulated Gate Type Field-Effect Transistor (AREA)
  • Bipolar Transistors (AREA)
  • Thyristors (AREA)

Abstract

本申请实施例提供一种IGBT器件，包括集电极；形成在集电极之上的电场终止层；形成在电场终止层之上的电场过渡层；形成在电场过渡层之上的漂移区，以及形成在漂移区内的多个的柱区；形成在漂移区上方的阱区；其中，电场过渡层的掺杂浓度<电场终止层的掺杂浓度，漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子；IGBT器件关断，所述电场过渡层被完全耗尽，电场在所述电场过渡层降低且在所述电场终止层减小至0，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低。本申请实施例解决了传统的SJ-IGBT器件在关断过程中关断损耗较大以及电场突变导致器件稳定性不足的技术问题。

Description

一种IGBT器件 技术领域
本申请涉及功率器件技术领域，具体地，涉及一种IGBT器件。
背景技术
绝缘栅双极型晶体管(Insulated Gate Bipolar Transistor，IGBT)作为全控型电压驱动式功率半导体器件，广泛应用于大功率电力变换领域。IGBT器件由双极型三极管(Bipolar Junction Transistor，BJT))和绝缘栅型场效应管(Metal Oxide Semiconductor，MOS)复合构成，兼有金属-氧化物-半导体场效晶体管(Metal-Oxide-Semiconductor Field-Effect Transistor，MOSFET)的高输入阻抗和电力晶体管(Giant Transistor，GTR)的低导通压降两方面的优点，适合应用于直流电压为600V及以上的变流系统如交流电机、变频器、开关电源、照明电路、牵引传动等领域。
超级结(Super Junction)技术为功率器件性能提升提供新的技术手段。利用交错排布的N型区和P型区，超级结结构能够将漂移区电场进行平坦化调控，有效降低功率器件漂移区厚度，以达到提升器件的击穿电压的目的。
传统的SJ-IGBT器件，如图1所示，1是P-集电区，2是N-漂移区，3是P型超级结区域，4是N型第二次外延，5是栅氧化层，6是栅极，7是Pwell，8是N+发射极，9是介质层，10是发射极金属，11是P+集电极，12是集电极金属。传统的超级结IGBT器件，N-漂移区2中位于P型超级结区域以下的部分会存储大量的空穴导致拖尾电流，拖尾电流导致关断损耗较大。
图2为图1所示的同一个传统的SJ-IGBT器件关断时发射极和集电极施加不同的电压形成的电场变化示意图，竖轴为图1中从Pwell7到N-漂移区2的距离，横轴为传统的SJ-IGBT器件在关断时发射极和集电极施加不同的电压形成的实 际电场的强度。传统的SJ-IGBT器件关断时，在发射极和集电极施加较低电压如200V时，电场终止在N-漂移区2内，虚线位置为电场终止的位置，这样，N-漂移区2虚线以上的部分空穴都被耗尽，但是N-漂移区2虚线以下的部分仍然存在空穴，因此产生拖尾电流，图2中，圆圈为空穴。由此可以看出，传统的SJ-IGBT器件关断时，在发射极和集电极施加的电压越小，拖尾电流越大，关断损耗越大。
相较于传统高压IGBT，SJ-IGBT器件作为新一代高速IGBT器件，具有更佳的器件优值。更低的导通压降、更低的开关损耗、更高的开关速度使得器件具备极大的应用价值，其优异的电学性能已经获得实验验证。
尽管SJ-IGBT器件性能已有很大提升，但受制于双极性器件电导调制效应，器件在关断过程依然存在拖尾电流问题，导致器件具有较大的关断能量损耗。
因此，传统的SJ-IGBT器件在关断过程中电场突变导致器件稳定性不足，是本领域技术人员急需要解决的技术问题。
在背景技术中公开的上述信息仅用于加强对本申请的背景的理解，因此其可能包含没有形成为本领域普通技术人员所知晓的现有技术的信息。
发明内容
本申请实施例提供了一种IGBT器件，以解决传统的SJ-IGBT器件在关断过程中关断损耗较大以及电场突变导致器件稳定性不足的技术问题。
本申请实施例的提供了一种IGBT器件，包括：
第一掺杂类型的集电极；
形成在所述集电极之上的第二掺杂类型的电场终止层；
形成在所述电场终止层之上的第二掺杂类型的电场过渡层；
形成在所述电场过渡层之上的第二掺杂类型的漂移区，以及形成在漂移区内且沿垂直耐压方向间隔排列的多个第一掺杂类型的柱区；
形成在所述漂移区上方的第一掺杂类型的阱区；
其中，电场过渡层的掺杂浓度<电场终止层的掺杂浓度，漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子；IGBT器件关断，所述电场过渡层被完全耗尽，电场在所述电场过渡层降低且在所述电场终止层减小至0，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低。
本申请实施例由于采用以上技术方案，具有以下技术效果：
电场过渡层的掺杂浓度<电场终止层的掺杂浓度，且漂移区、电场过渡层、电场终止层三层中仅有两层漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子，但是电场终止层不能发生电导调制效应不能积累少数载流子；即电场过渡层的掺杂浓度较低，且掺杂浓度低到能够发生电导调制效应积累少数载流子；电场终止层的掺杂浓度较高，且掺杂浓度高到几乎不会发生电导调制效应不会积累少数载流子。当IGBT器件的沟道形成后，从集电极注入到漂移区和电场过渡层的少数载流子，漂移区和电场过渡层发生电导调制效应，减小漂移区和电场过渡层的电阻，使IGBT器件在导通时，具有低的通态电压。即通过电导调制效应降低漂移区和电场过渡层的电阻。由于电导调制效应的存在，使得IGBT器件在导通时，集电极将少数载流子大量注入到漂移区和电场过渡层内进行积累。IGBT器件在关断时，电场迅速向下展宽，漂移区和电场过渡层中存储的少数载流子很快被耗尽，即电场过渡层被完全耗尽；而电场终止层由于掺杂浓度较高，几乎不存储少数载流子，因此拖尾电流变得很小。为了尽快实现将电场过渡层积累的少数载流子完全耗尽，需要将电场过渡层的厚度设置的小一些。因为电场过渡层的厚度较小，那么电场过渡层积累的少数载流子的数量就会较少，能够在电场过渡层内经较短的时间内耗尽。因此不会产生拖尾电流，从而使得IGBT器件的关断能量损耗较小。同时，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低，防止了电场在电场过渡层和电场终止层的交界位置的突变，使得IGBT器件的稳定性较高。
附图说明
此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部 分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：
图1为背景技术中传统的SJ-IGBT器件的结构示意图；
图2为图1所示的同一个传统的SJ-IGBT器件在关断时发射极和集电极的不同的电压形成的电场变化示意图；
图3为本申请实施例的IGBT器件的结构示意图；
图4为图3所示的电场在电场过渡层和电场终止层的交界位置自上而下平滑降低的IGBT器件在关断时发射极和集电极的不同电压形成的电场变化示意图。
附图标记：
背景技术中：
P-集电区1，N-漂移区2，P型超级结区域3，第二次外延4，栅氧化层5，栅极6，Pwell7，N+发射极8，介质层9，发射极金属10，P+集电极11，集电极金属12；
本申请具体实施方式中：
电场过渡层1，漂移区2，柱区3，第二掺杂类型的外延层4，栅氧化层5，栅极6，阱区7，发射极8，介质层9，发射极金属10，电场终止层11，集电极12，集电极金属13。
具体实施方式
为了使本申请实施例中的技术方案及优点更加清楚明白，以下结合附图对本申请的示例性实施例进行进一步详细的说明，显然，所描述的实施例仅是本申请的一部分实施例，而不是所有实施例的穷举。需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。
实施例一
如图3所示，本申请实施例的IGBT器件，包括：
第一掺杂类型的集电极12；
形成在所述集电极之上的第二掺杂类型的电场终止层11；
形成在所述电场终止层之上的第二掺杂类型的电场过渡层1；
形成在所述电场过渡层之上的第二掺杂类型的漂移区2，以及形成在漂移区内且沿垂直耐压方向间隔排列的多个第一掺杂类型的柱区3；
形成在所述漂移区上方的第一掺杂类型的阱区7；
其中，电场过渡层的掺杂浓度<电场终止层的掺杂浓度，漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子；IGBT器件关断，所述电场过渡层被完全耗尽，电场在所述电场过渡层降低且在所述电场终止层减小至0，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低。
本申请实施例的IGBT器件，电场过渡层的掺杂浓度<电场终止层的掺杂浓度，且漂移区、电场过渡层、电场终止层三层中仅有两层漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子，但是电场终止层不能发生电导调制效应不能积累少数载流子；即电场过渡层的掺杂浓度较低，且掺杂浓度低到能够发生电导调制效应积累少数载流子；电场终止层的掺杂浓度较高，且掺杂浓度高到几乎不会发生电导调制效应不会积累少数载流子。当IGBT器件的沟道形成后，从集电极注入到漂移区和电场过渡层的少数载流子，漂移区和电场过渡层发生电导调制效应，减小漂移区和电场过渡层的电阻，使IGBT器件在导通时，具有低的通态电压。即通过电导调制效应降低漂移区和电场过渡层的电阻。由于电导调制效应的存在，使得IGBT器件在导通时，集电极将少数载流子大量注入到漂移区和电场过渡层内进行积累。IGBT器件在关断时，电场迅速向下展宽，漂移区和电场过渡层中存储的少数载流子很快被耗尽，即电场过渡层被完全耗尽；而电场终止层由于掺杂浓度较高，几乎不存储少数载流子，因此拖尾电流变得很小。为了尽快实现将电场过渡层积累的少数载流子完全耗尽，需要将电场过渡层的厚度设置的小一些。因为电场过渡层的厚度较小，那么电场过渡层积累的少数载流子的数量就会较少，能够在电场过渡层内经较短的时间内耗尽。因此不会产生拖尾电流，从而使得IGBT器件的关断能量损 耗较小。同时，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低，防止了电场在电场过渡层和电场终止层的交界位置的突变，使得IGBT器件的稳定性较高。电场下降的速率对应IGBT器件关断时电流的变化速率，电场下降越快，电流变化速率越大，即电流的变化速率di/dt越大，导致器件的过冲电压较大，可能导致器件损坏。
电场在电场过渡层和电场终止层的交界位置自上而下平滑降低，平滑降低进行量化表达如下：
电场在电场过渡层的下表面的斜率T过渡层下表面与电场在电场终止层的上表面的斜率T终止层上表面满足如下关系式：
(T终止层上表面—T过渡层下表面)/T终止层上表面≤10％。
电场在电场过渡层缓慢降低，在电场终止层快速降低，因此，在电场过渡层和电场终止层的交界位置是电场发生较大变化的位置。因此，通过控制电场在电场过渡层和电场终止层的交界位置的电场变化，使得电场在电场过渡层和电场终止层的交界位置不会发生突变，而是平滑降低。
为了实现电场在电场过渡层和电场终止层的交界位置自上而下平滑降低，实现的方式为对电场过渡层和电场终止层的交界位置的掺杂浓度进行控制。电场过渡层下表面的掺杂浓度R过渡层下表面与电场终止层上表面的掺杂浓度R终止层下表 面的满足如下关系式：
(R终止层上表面—R过渡层下表面)/R终止层上表面≤10％。
这样，电场过渡层下表面和电场终止层下表面的掺杂浓度的差值较小。
实施中，电场过渡层的掺杂浓度自电场过渡层的上表面到下表面逐渐增大。
这样，电场过渡层的掺杂浓度越接近电场过渡层的下表面越大，与电场终止层的上表面的掺杂浓度的差值越小。
作为一种可实施的方式，电场过渡层的掺杂浓度自电场过渡层的上表面到下表面逐渐增大，且电场过渡层的掺杂为线性变化掺杂。
作为另一种可实施的方式，电场过渡层的掺杂浓度自电场过渡层的上表面到下表面逐渐增大，且电场过渡层的掺杂为半正态分布。正态分布的曲线呈钟型，两头低，中间高，左右对称。半正态分布的曲线是正态分布的一半。这样，电场过渡层的掺杂浓度从电场过渡层的上表面向下表面，斜率越来越大，在电场过渡层的下表面斜率达到最大。电场过渡层本层内的掺杂浓度是平滑增大，电场过渡层的下表面和电场终止层的上表面的交界位置掺杂浓度也是平滑增大。
实施中，电场过渡层的电荷总量Q总小于等于k％×Ec/εs；
其中，k％为IGBT器件的最小预设工作电压条件下电场强度占临界击穿电场强度的百分比，Ec为IGBT器件Si衬底的临界击穿场强，εs为IGBT器件Si衬底的介电常数。
为了尽快实现将电场过渡层积累的少数载流子完全耗尽，电场过渡层的电荷总量Q总需要满足预设条件Q总小于k％×Ec/εs，能够在电场过渡层内经较短的时间内耗尽。因此不会产生拖尾电流，从而使得IGBT器件的关断能量损耗较小。
实施中，k％的取值范围为大于等于10％小于等于80％。
作为一种可选的方式，所述第一掺杂类型为N型掺杂，所述第二掺杂类型为P型掺杂。在此情况下，少数载流子为电子。
作为另一种可选的方式，所述第一掺杂类型为P型掺杂；所述第二掺杂类型为N型掺杂。在此情况下，少数载流子为空穴。本申请实施例的IGBT器件尤其适用于第一掺杂类型为P型掺杂、所述第二掺杂类型为N型掺杂的情况。具体的，电场过渡层1为N型轻掺杂，电场终止层11为N型重掺杂，漂移区 2为N型轻掺杂，外延层4为N型轻掺杂，发射极8为N型重掺杂，集电极12为P型重掺杂。
实施中，电场过渡层的掺杂为线性变化掺杂时，电场过渡层的电荷总量Q总和电场过渡层厚度Wp满足以下关系：
Q总＝q×G×Wp2/2；
其中，q为单个电子的电荷量，G为线性变化掺杂的斜率。
这样，在Q总<k％×Ec/εs的条件下，可以先确定一个Q总的具体数值，之后就能够根据Q总＝q×G×Wp2/2找出线性变化掺杂的斜率G和电场过渡层厚度Wp满足的关系。最后通过选择多个电场过渡层厚度值进行仿真的方法，选择出效果最佳IGBT器件。
下面从物理原理上对电场过渡层的电荷总量Q总满足的预设条件进行说明：
电场过渡层电场强度E(x)和电荷总量Q(x)满足以下关系式：
-dE/dx＝-Q(x)/εs
即E(x)＝∫Q(x)/εs×d(x)；公式一
其中，εs为Si的介电常数，d(x)为电场过渡层的上表面和下表面沿电场强度方向的距离。公式一是电场过渡层电场强度和电荷总量的普适性公式。
本申请想要实现在IGBT器件在不同电压条件下关断，电流拖尾都很小甚至不存在电流拖尾。假定IGBT器件的最小预设工作电压为k％×BV，BV为IGBT器件的击穿电压，对应的IGBT器件最小预设工作电压对应的最大场强Em近似为k％×Ec，k％为IGBT器件的最小预设工作电压条件下电场强度占临界击穿电场强度的百分比，即过渡层上表面的电场强度为k％×Ec，Ec为Si的临界击穿场强，εs为Si的介电常数。临界条件为电场过渡层的下表面电场强度等于0，对应的，临界条件下电场过渡层的电荷总量Q临界。对于临界条件为电场过渡层的下表面电场强度等于0这种特定的情况，公式一可以简化为：
k％×Ec＝Q临界/εs，公式二；
即能推出：Q临界＝k％×Ec/εs；其中，εs为Si的介电常数。
因此，电场过渡层的电荷总量Q总应小于Q临界，即Q总<k％×Ec/εs。Q总<k％×Ec/εs是IGBT器件的最小预设工作电压为k％×BV且临界条件为电场过渡层的下表面电场强度等于0这种特定情况下，电场过渡层电场强度和电荷总量的适用的关系式，在这种特定情况下，不仅适用于电场过渡层的掺杂为均匀掺杂的情况下，而且也适用于电场过渡层的掺杂为不均匀掺杂的情况下。至此，在IGBT器件的最小预设工作电压为k％×BV且临界条件为电场过渡层的下表面电场强度等于0这种特定情况下，电场过渡层的电荷总量Q总的要求已经确定。
实施中，如图3所示，所述柱区3的下端和漂移区2的下端平齐，所述柱区3的下端和漂移区2的下端分别与电场过渡层1的上表面连接。
实施中，如图3所示，IGBT器件还包括：
第二掺杂类型的外延层4，形成在所述漂移区2之上且位于阱区7之下；
其中，所述柱区3的上端和漂移区2的上端平齐，且所述柱区3的上端和漂移区2的上端分别与所述外延层4的下表面连接。
通过设置外延层4，实现了柱区3的上端、下端、左端和右端，都是第二掺杂类型区，即实现了柱区3的浮空设置。柱区浮空，集电极注入柱区的少数载流子会存储的更多，使得导通状态下的通态压降更低。
实施中，如图3所示，IGBT器件还包括：
集电极金属13，形成在集电极12之下；
栅极沟槽，自所述阱区7的上表面向下伸入到所述外延层4内；
栅氧化层5，形成在所述栅极沟槽内；
栅极6，形成在所述栅氧化层5之上，且所述栅极与所述阱区7的上表面 平齐；
第二掺杂类型的发射极8，自所述阱区7的上表面向下，且发射极8的深度比阱区7浅；
介质层9，覆盖在所述栅极和栅氧化层之上且部分覆盖发射极8；
发射极金属10，形成在所述发射极8和介质层9之上；其中，所述介质层9用于将所述栅极和所述发射极金属10绝缘。
即IGBT器件为沟槽栅极的超级结IGBT器件。
图4为图3所示的电场在电场过渡层和电场终止层的交界位置自上而下平滑降低的IGBT器件在关断时发射极和集电极的不同电压形成的电场变化示意图，竖轴为图3中从阱区7到漂移区2的距离，横轴为图3所示的IGBT器件在关断时发射极和集电极随着电压增加时实际电场的分布情况。
如图3和图4所示，在IGBT器件关断时，电场迅速向下展宽，漂移区与过渡层中存储的少数载流子很快被消耗，而电场终止层由于掺杂浓度较高，几乎不存储少数载流子，因此拖尾电流变得很小。
本申请中，电场过渡层较薄，从电场分布可以看出同一器件在不同电压条件下电场最终都在电场终止层终止，如图4。因此不论在哪个电压条件下将IGBT器件关断，电流拖尾都很小甚至不存在电流拖尾。
而传统超级结器件在不同电压条件下电场截止在漂移区的不同位置如图2，当电压较小时未耗尽的漂移区较宽，因此关断时未耗尽的漂移区会导致电流拖尾，电压越高电流拖尾越小。因此与传统超级结结构相比，本申请实施例的IGBT器件，既能在高压使用，又能在低压使用，且即使在低压条件下，也没有拖尾电流，关断损耗较小。
本申请中，电场终止层的掺杂浓度为1017/cm3到5×1017/cm3，即电场终止层的掺杂浓度足够高，电场终止层不会发电导调制效应，即电场终止层内不会 积累少数载流子，电场终止层所起的作用仅仅是电场在电场终止层线性降低至零，实现电场的终止。即电场终止层仅起到快速将电场终止的作用。
本申请中，电场过渡层的掺杂浓度的量级1013/cm3到1015/cm3，因此电场过渡层会发生电导调制效应，同时也能起到承受部分击穿电压的作用。
具体的，电场终止在电场终止层内，且电场终止在电场终止层内的位置和电场终止层的下表面之间具有预设距离，以防止击穿。
电场经电场过渡层降低后，在电场终止层内线性快速降低实现电场的终止。
具体的，电场过渡层的厚度<电场终止层的厚度。
这样，IGBT器件关断，所述电场过渡层被完全耗尽，因此要求电场过渡层的厚度较薄。而电场终止层的厚度需要防止击穿，需要的厚度较大。因此，电场过渡层的厚度<电场终止层的厚度。
具体的，电场过渡层的掺杂浓度至少低于电场终止层的掺杂浓度的1-1.5个数量级。
具体的，外延层的掺杂浓度<漂移区的掺杂浓度，外延层的掺杂浓度略低于漂移区。
具体的，漂移区的掺杂浓度的量级为1014/cm3到1015/cm3，柱区的掺杂浓度和漂移区的掺杂浓度位于同一数量级上，漂移区与柱区的电荷量要相等。
即漂移区和柱区要达到电荷平衡。
IGBT器件的制备工艺如下：
步骤S11：在硅基片上长第一次外延；
步骤S12：挖柱区对应的深槽，填充柱区对应的深槽；
步骤S13：长第二次外延；
步骤S14：挖栅极对应的沟槽，在栅极对应的沟槽内长栅氧化层，在栅氧 化层之上垫多晶硅并磨平，至此栅极做完；
步骤S15：在第二次外延的上表面进行离子注入或者热扩散形成阱区7，阱区7的深度比栅极对应的沟槽浅；
步骤S16：在第二次外延的上表面进行离子注入或者热扩散形成发射极8，发射极8的深度比阱区7浅；
步骤S17：形成介质层9；
步骤S18：形成发射极金属10。
至此，完成IGBT器件的正面工艺。
之后，把器件翻过来，在背面进行离子注入，形成集电极12和集电极金属13。
实施例二
实施例二的IGBT器件，在实施例一的基础之上，还具有如下特点。
实施中，IGBT器件的预设工作电压为大于等于10％×BV小于等于80％×BV，BV为IGBT器件的击穿电压。
IGBT器件的预设工作电压为大于等于10％×BV小于等于80％×BV，即IGBT器件的预设工作电压的范围很宽。本申请实施例的IGBT器件的预设工作电压的范围很宽能够实现的原因在于，IGBT器件的实际工作电压在预设工作电压范围内时，不论是高压还是低压，在关断时，电场都能迅速向下展宽，漂移区和电场过渡层中存储的少数载流子很快被耗尽，即电场过渡层都能被完全耗尽；而电场终止层由于掺杂浓度较高，几乎不存储少数载流子，因此拖尾电流变得很小或接近零。这样，本申请实施例的IGBT器件，实现了将拖尾电流不再与实际工作电压有关。传统的超级结器件，拖尾电流的大小与超级结器件的实际工作电压有关，实际工作电压越小，拖尾电流越大。因此与传统超级结结构相比，本申请实施例的IGBT器件，既能在预设工作电压范围内的高压使用，又能在预设工作电压范围内的低压使用，且即使在低压条件下，也 没有拖尾电流，关断损耗较小。
具体的，IGBT器件的预设工作电压为大于等于10％×BV小于等于80％×BV，即IGBT器件的最小预设工作电压为10％×BV，IGBT器件的最大预设工作电压为80％×BV。
具体的，IGBT器件的预设工作电压的优选取值范围为大于等于60％×BV小于等于70％×BV。
IGBT器件的实际工作电压取值在大于等于60％×BV小于等于70％×BV，IGBT器件的工作状态较为稳定。
在本申请的描述中，需要理解的是，术语“前”、“后”、“首”、“尾”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本申请和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请的限制。
此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个该特征。在本申请的描述中，“多个”的含义是至少两个，例如两个，三个等，除非另有明确具体的限定。
在本申请中，除非另有明确的规定和限定，术语“安装”、“连接”等术语应做广义理解；以连接为例，可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通或两个元件的相互作用关系。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请中的具体含义。
尽管已描述了本申请一些可选的实施例，但本领域内的技术人员一旦得知了基本创造性概念，则可对这些实施例作出另外的变更和修改。所以，所附权利要求意欲解释为包括一些可选的实施例以及落入本申请范围的所有变更和修改。
显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申 请的精神和范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (10)

  1. 一种IGBT器件，其特征在于，包括：
    第一掺杂类型的集电极(12)；
    形成在所述集电极之上的第二掺杂类型的电场终止层(11)；
    形成在所述电场终止层之上的第二掺杂类型的电场过渡层(1)；
    形成在所述电场过渡层之上的第二掺杂类型的漂移区(2)，以及形成在漂移区内且沿垂直耐压方向间隔排列的多个第一掺杂类型的柱区(3)；
    形成在所述漂移区上方的第一掺杂类型的阱区(7)；
    其中，电场过渡层的掺杂浓度<电场终止层的掺杂浓度，漂移区和电场过渡层分别能够发生电导调制效应积累少数载流子；IGBT器件关断，所述电场过渡层被完全耗尽，电场在所述电场过渡层降低且在所述电场终止层减小至0，电场在电场过渡层和电场终止层的交界位置自上而下平滑降低。
  2. 根据权利要求1所述的IGBT器件，其特征在于，电场在电场过渡层的下表面的斜率T过渡层下表面与电场在电场终止层的上表面的斜率T终止层上表面满足如下关系式：
    (T终止层上表面—T过渡层下表面)/T终止层上表面≤10％。
  3. 根据权利要求1所述的IGBT器件，其特征在于，电场过渡层下表面的掺杂浓度R过渡层下表面与电场终止层上表面的掺杂浓度R终止层下表面的满足如下关系式：
    (R终止层上表面—R过渡层下表面)/R终止层上表面≤10％。
  4. 根据权利要求3所述的IGBT器件，其特征在于，电场过渡层的掺杂浓度自电场过渡层的上表面到下表面逐渐增大。
  5. 根据权利要求4所述的IGBT器件，其特征在于，电场过渡层的掺杂为线性变化掺杂或者电场过渡层的掺杂为半正态分布。
  6. 根据权利要求1至5任一所述的IGBT器件，其特征在于，电场过渡层的电荷总量Q总小于等于k％×Ec/εs；
    其中，k％为IGBT器件的最小预设工作电压条件下电场强度占临界击穿电场强度的百分比，Ec为IGBT器件Si衬底的临界击穿场强，εs为IGBT器件Si衬底的介电常数。
  7. 根据权利要求6所述的IGBT器件，其特征在于，电场过渡层的掺杂为线性变化掺杂时，电场过渡层的电荷总量Q总和电场过渡层厚度Wp满足以下关系：
    Q总＝q×G×Wp2/2；
    其中，q为单个电子的电荷量，G为线性变化掺杂的斜率。
  8. 根据权利要求6所述的IGBT器件，其特征在于，所述柱区(3)的下端和漂移区(2)的下端平齐，且所述柱区(3)的下端和漂移区(2)的下端分别与电场过渡层(1)的上表面连接。
  9. 根据权利要求8所述的IGBT器件，其特征在于，还包括：
    第二掺杂类型的外延层(4)，形成在所述漂移区(2)之上且位于阱区(7)之下；
    其中，所述柱区(3)的上端和漂移区(2)的上端平齐，且所述柱区(3)的上端和漂移区(2)的上端分别与所述外延层的下表面连接。
  10. 根据权利要求9所述的IGBT器件，其特征在于，还包括：
    集电极金属(13)，形成在集电极(12)之下；
    栅极沟槽，自所述阱区(7)的上表面向下伸入到所述外延层(4)内；
    栅氧化层(5)，形成在所述栅极沟槽内；
    栅极(6)，形成在所述栅氧化层(5)之上，且所述栅极与所述阱区(7)的上表面平齐；
    第二掺杂类型的发射极(8)，自所述阱区(7)的上表面向下，且发射极(8)的深度比阱区(7)浅；
    介质层(9)，覆盖在所述栅极和栅氧化层之上且部分覆盖发射极(8)；
    发射极金属(10)，形成在所述发射极(8)和介质层(9)之上；其中， 所述介质层(9)用于将所述栅极和所述发射极金属绝缘。
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104637994A (zh) * 2013-11-13 2015-05-20 上海华虹宏力半导体制造有限公司 半导体器件及制造方法
CN106298898A (zh) * 2015-06-12 2017-01-04 中芯国际集成电路制造(上海)有限公司 垂直导电功率器件及其制作方法
CN113471273A (zh) * 2020-03-31 2021-10-01 比亚迪半导体股份有限公司 绝缘栅双极型晶体管及制备方法、电子设备
CN113644123A (zh) * 2021-06-28 2021-11-12 华为技术有限公司 半导体器件及相关芯片和制备方法
CN114300528A (zh) * 2021-12-28 2022-04-08 深圳市千屹芯科技有限公司 低关断损耗的超级结绝缘栅双极型晶体管及其制作方法
US20220254877A1 (en) * 2021-02-07 2022-08-11 Huawei Technologies Co., Ltd. Semiconductor device, and related module, circuit, and preparation method

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001210823A (ja) * 2000-01-21 2001-08-03 Denso Corp 半導体装置
US20070181927A1 (en) * 2006-02-03 2007-08-09 Yedinak Joseph A Charge balance insulated gate bipolar transistor
CN103594504A (zh) * 2013-11-19 2014-02-19 西安永电电气有限责任公司 具有半超结结构的igbt
US9761702B2 (en) * 2014-02-04 2017-09-12 MaxPower Semiconductor Power MOSFET having planar channel, vertical current path, and top drain electrode
US9559171B2 (en) * 2014-10-15 2017-01-31 Fuji Electric Co., Ltd. Semiconductor device
JP6746978B2 (ja) * 2016-03-15 2020-08-26 富士電機株式会社 半導体装置
US10580884B2 (en) * 2017-03-08 2020-03-03 D3 Semiconductor LLC Super junction MOS bipolar transistor having drain gaps
CN113838918B (zh) * 2021-09-23 2023-10-24 电子科技大学 具有载流子浓度增强的超结igbt器件结构及制作方法
CN116469910B (zh) * 2022-09-09 2024-02-02 苏州华太电子技术股份有限公司 一种igbt器件
CN116469911B (zh) * 2022-09-09 2024-10-18 苏州华太电子技术股份有限公司 一种igbt器件
CN116469909B (zh) * 2022-09-09 2024-08-13 苏州华太电子技术股份有限公司 一种半导体集成器件
CN116525644A (zh) * 2022-09-09 2023-08-01 苏州华太电子技术股份有限公司 一种二极管器件
CN116525646B (zh) * 2022-09-23 2024-05-14 深圳市千屹芯科技有限公司 一种igbt器件及开关电路
CN116525645A (zh) * 2022-09-23 2023-08-01 深圳市千屹芯科技有限公司 一种半导体器件
CN219759593U (zh) * 2022-09-23 2023-09-26 深圳市千屹芯科技有限公司 一种半导体器件

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104637994A (zh) * 2013-11-13 2015-05-20 上海华虹宏力半导体制造有限公司 半导体器件及制造方法
CN106298898A (zh) * 2015-06-12 2017-01-04 中芯国际集成电路制造(上海)有限公司 垂直导电功率器件及其制作方法
CN113471273A (zh) * 2020-03-31 2021-10-01 比亚迪半导体股份有限公司 绝缘栅双极型晶体管及制备方法、电子设备
US20220254877A1 (en) * 2021-02-07 2022-08-11 Huawei Technologies Co., Ltd. Semiconductor device, and related module, circuit, and preparation method
CN113644123A (zh) * 2021-06-28 2021-11-12 华为技术有限公司 半导体器件及相关芯片和制备方法
CN114300528A (zh) * 2021-12-28 2022-04-08 深圳市千屹芯科技有限公司 低关断损耗的超级结绝缘栅双极型晶体管及其制作方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4593085A4 *

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