Semiconductor device and method for operating a semiconductor device - Patents.com

Abstract

According to one embodiment, a semiconductor device (100) comprises a semiconductor body (1), a first electrode (2), a gate electrode (3) and a variable resistance element (4). The variable resistance element is electrically connected to the gate electrode and the first electrode. The variable resistance element has at least a first and a second state. In the first state, the variable resistance element acts as an electrical insulator to prevent current from flowing from the first electrode to the gate electrode through the variable resistance element, or vice versa. In the second state, the variable resistance element acts as an electrical conductor to allow current to flow from the first electrode to the gate electrode through the variable resistance element, or vice versa. The variable resistance element is configured to transition from the first state to the second state when the temperature of the variable resistance element rises above a critical temperature Tc.

Description

[Technical field]

[0001] The present disclosure relates to semiconductor devices and methods for operating semiconductor devices. [Background technology]

[0002] Short circuit robustness is a key requirement for the majority of applications, e.g. in power electronics. During a short circuit, the device must withstand both high voltages and high currents for a certain period of time. If the short circuit condition is not detected or limited early enough, the device is eventually destroyed. Understanding short circuits is an item of great research interest, since failures can occur during different parts of the short circuit pulse (turn-on, plateau, turn-off, thermal runaway) and the underlying physical mechanisms can be of different nature. Even the failure of one weak chip under short circuit conditions can cause an explosion and severe damage to the whole system. The importance of preventing short circuit failures leads to design constraints and can cause severe limitations in device performance.

[0003] US 2016 / 163689 relates to a semiconductor device having a transistor cell and a thermal resistance element. EP 2 937 960 relates to a method for automatically shutting off high temperatures and high currents. US 2010 / 001785 relates to a semiconductor component and a method for determining the temperature. Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for improved semiconductor devices, e.g., semiconductor devices with automatic short circuit suppression and / or improved short circuit tolerance, and further, there is a need for methods for operating such semiconductor devices. [Means for solving the problem]

[0005] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to improved semiconductor devices, such as semiconductor devices with automatic short circuit detection and suppression and / or improved short circuit tolerance. Additionally, embodiments relate to methods for operating such semiconductor devices.

[0006] First, a semiconductor device is defined. According to one embodiment, a semiconductor device comprises a semiconductor body, a first electrode, a gate electrode, and a variable resistance element. The variable resistance element is electrically connected to the gate electrode and the first electrode. The variable resistance element has at least a first and a second state. In the first state, the variable resistance element acts as an electrical insulator to prevent current from flowing from the first electrode to the gate electrode through the variable resistance element, or vice versa. In the second state, the variable resistance element acts as an electrical conductor to allow current to flow from the first electrode to the gate electrode through the variable resistance element, or vice versa. The variable resistance element is configured to transition from the first state to the second state when the temperature of the variable resistance element rises above a critical temperature Tc.

[0007] A variable resistance element between the first electrode and the gate electrode realizes a smart gate signal fuse for detecting and reacting to short circuits. The variable resistance element has a very low electrical conductivity under normal operating conditions of the device, i.e. when the temperature is below Tc. Thus, the variable resistance element effectively acts as an electrical insulator. When the device, and with it the variable resistance element, heats up above the critical temperature Tc, for example due to a short circuit, it undergoes a heat-induced increase in electrical conductivity such that it effectively acts as a conductor.

[0008] For example, for a semiconductor device that is an insulated gate transistor, the threshold voltage V TH A gate voltage higher than V 1EWhen a gate voltage V (a voltage between the first and gate electrodes) is applied, a large current starts to flow through the device and the average temperature of the device increases. Under normal operating conditions, this temperature increase is not enough to reach the critical temperature Tc at the location where the variable resistance element is located. However, under short circuit conditions, for example when the device is in a cut-off state, the device reaches a higher temperature level and eventually exceeds the critical temperature Tc. When the variable resistance element starts to conduct, the gate voltage V 1E decreases, and finally V th , causing a reduction in the current through the device. The reduction in current allows for the device to stop self-heating and destruction even if external detection is delayed.

[0009] Thus, one advantage of the presented semiconductor device is that it allows for fast on-chip short circuit detection and reaction, providing all the attendant chip optimization advantages of a fast short circuit detection system that is not limited to more complex "fast" detection systems at the system level, i.e., off-chip. Thus, the on-chip protection method disclosed herein provides, among other things, an opportunity to reduce the cost / complexity of system-level short circuit protection design.

[0010] The semiconductor device may be a semiconductor chip. The semiconductor body may be, for example, silicon-based. The first electrode may be, for example, an emitter electrode, if the semiconductor device is an IGBT or RC-IGBT. Alternatively, the first electrode may be, for example, a source electrode, if the semiconductor device is a MOSFET. The first electrode may include or consist of a metal.

[0011] The gate electrode may be electrically insulated from the semiconductor body and / or the first electrode in normal operation of the semiconductor device. In other words, the semiconductor device may be an insulated gate device. For example, an insulating material such as SiO2 is disposed between the gate electrode and the semiconductor body. Thus, when the variable resistance element is in the first state, the gate electrode is electrically insulated from the semiconductor body and / or the first electrode. The gate electrode may include or consist of one or more of a metal and highly doped polysilicon.

[0012] The variable resistance element can extend through the insulating material, for example the insulating material surrounds the resistance element laterally, where lateral is understood to be the direction parallel to the plane of main extent of the semiconductor body.

[0013] The variable resistance element is electrically connected to the gate electrode and the first electrode. This means that the variable resistance element is directly or indirectly electrically connected to the gate electrode and / or the first electrode. "Directly electrically connected" in this specification means that the variable resistance element is in direct contact with the respective electrode, i.e., there is a direct mechanical contact. "Indirectly electrically connected" in this specification means that there is no direct mechanical contact, but a further conductive material, such as a part of a semiconductor body, is disposed between the variable resistance element and the respective electrode. For example, the variable resistance element is directly electrically connected to the gate electrode and indirectly electrically connected to the first electrode. For example, the variable resistance element is disposed between the gate electrode and the semiconductor body.

[0014] In the first state, the variable resistance element acts substantially as an insulator. For example, in the first state, the variable resistance element has a resistance of up to 10 S / m or up to 1·10 -2 S / m or max 1·10 -5 It has a conductivity of S / m.

[0015] In the second state, the variable resistance element acts substantially as a conductor. For example, in the second state, the variable resistance element has a resistance of at least 10 2 S / m or at least 10 5 S / m or at least 10 8 It has a conductivity of S / m.

[0016] For example, the conductivity in the first state is at least 2 orders of magnitude, or at least 5 orders of magnitude, or at least 10 orders of magnitude less than the conductivity in the second state.

[0017] For example, the variable resistance element has a voltage difference V between the gate electrode and the first electrode in the first state of the variable resistance element. 1E appears, and therefore when the variable resistance element switches to the second state, a current flows between the electrodes through the variable resistance element, causing a voltage difference V 1E is automatically decreased. Therefore, V 1E For example, the threshold voltage V of the semiconductor device in the first state is reduced by at least 20%, or at least 50%, or at least 90%. th Voltage difference exceeding V 1E is V in the second state th The voltage difference decreases to below

[0018] The variable resistance element may be configured to transition from the first state to the second state automatically. This means that the variable resistance element is not externally switched from the first state to the second state. Rather, a change in temperature above Tc automatically results in a change in the resistance of the variable resistance element, since the physical and / or chemical properties of the variable resistance element that affect its resistance are temperature dependent. Alternatively, the variable resistance element may be configured to transition from the first state to the second state upon a trigger, such as an external trigger.

[0019] The variable resistance element is configured to transition from a first state to a second state when the temperature rises above the critical temperature Tc. This may mean that the variable resistance element remains in the first state when the temperature rises from T < Tc to the temperature Tc. When the temperature further rises by ΔT from Tc, the conductivity changes such that the variable resistance element assumes the second state at the temperature Tc + ΔT. This means that the second state is reached precisely at the temperature T = Tc + ΔT, rather than just before and after the temperature T = Tc + ΔT. That is, the transition occurs in the range Tc < T < T + ΔT.

[0020] According to a further embodiment, the variable resistance element is located in a region below the gate pad terminal of the gate electrode among the semiconductor devices. The gate pad terminal is a region of the gate electrode configured to be in electrical contact with the outside during the operation of the semiconductor device. For example, the gate pad terminal is disposed at the edge and / or corner of the semiconductor device. The gate pad terminal may be a region of the gate electrode having the largest diameter / width of the gate electrode. In a top view, the gate pad terminal may have a rectangular shape.

[0021] According to a further embodiment, the semiconductor device includes several variable resistance elements. All the features disclosed so far in relation to one resistance element, and all the features disclosed below, are also disclosed for the other resistance elements. Different resistance elements may be arranged at different positions of the semiconductor device. For example, different variable resistance elements are spaced apart from each other. The variable resistance elements may be connected in parallel with each other between the gate electrode and the first electrode.

[0022] According to a further embodiment, the variable resistance element is disposed below the gate runner of the gate electrode. The gate runner is a portion of the gate electrode that extends laterally around the first electrode and / or along the edge of the semiconductor device. For example, the gate runner extends from the gate pad terminal along the edge of the semiconductor device and reaches the gate pad terminal again. The gate runner may be in a frame shape.

[0023] For example, a plurality of variable resistance elements are disposed beneath the gate runner, for example, the variable resistance elements being uniformly, i.e. at regular intervals, along the extension of the gate runner.

[0024] The variable resistance element may be disposed between the gate electrode and the semiconductor body and / or may extend at least partially into the semiconductor body, e.g., the variable resistance element may be at least partially laterally surrounded by the semiconductor body.

[0025] The variable resistance element being arranged below the electrode may mean that in a top view, the electrode overlaps the variable resistance element, for example on a major surface of the semiconductor body.

[0026] In top view, the variable resistance element may have an oval or circular or rectangular shape, for example with a maximum lateral extent of at least 1 μm or at least 10 μm and / or up to 1000 μm or up to 100 μm.

[0027] According to a further embodiment, the variable resistance element is placed in an area of ​​the semiconductor device that is expected to have the highest temperature in the event of a short circuit, which area can be determined with the aid of a computer simulation.

[0028] The location of the variable resistive element may be selected depending on the requirements of short circuit protection. For example, to make the resistive element respond quickly, the resistive element is placed close to the area where the heat source or short circuit appears. For example, to make the resistive element respond slowly, the resistive element is placed far from the area where the heat source or short circuit appears.

[0029] According to a further embodiment, the variable resistance element comprises or is made of at least one phase change material (PCM for short), which is a material that is able to change its phase, for example from amorphous to crystalline, when the temperature is increased above a critical temperature Tc, thus resulting in a large change in electrical conductivity.

[0030] According to a further embodiment, the conductivity of the variable resistance element in the second state is at least 10 times, or at least 100 times, or at least 10 times, the conductivity of the variable resistance element in the first state. 3 times or at least 10 4 times or at least 10 5 times or at least 10 6 It is double.

[0031] According to a further embodiment, the variable resistance element is configured to abruptly transition from the first state to the second state when the temperature of the variable resistance element rises above a critical temperature Tc. The term "abrupt" in this specification relates to the temperature range ΔT in which the transition occurs. For example, the temperature range ΔT in which the transition from the first state to the second state occurs is up to 30°C or up to 10°C or up to 5°C. This type of variable resistance element may also be referred to as a digital variable resistance element in this specification.

[0032] Alternatively, the variable resistance element may be configured to transition smoothly or gradually from the first state to the second state when the temperature of the variable resistance element rises above a critical temperature Tc. "Smooth" or "gradual" also refers to a temperature range ΔT. For example, the temperature range ΔT in which the transition from the first state to the second state occurs is at least 50°C or at least 75°C or at least 100°C, and / or up to 200°C. In particular, when switching from the first state to the second state, the second state is not reached until a temperature T=Tc+ΔT. This type of variable resistance element may also be referred to herein as an analog variable resistance element. Such a variable resistance element can realize a self-adjusting gate current.

[0033] For example, the critical temperature Tc and / or the temperature range ΔT can be adjusted by adjusting the doping concentration in the material of the resistive element.

[0034] According to further embodiments, the critical temperature Tc is at least 50° C., or at least 75° C., or at least 100° C. higher than the normal operating temperature of the semiconductor device. The normal operating temperature of the semiconductor device, i.e. the operating mode in which no short circuits are present, may be at least 100° C. and / or up to 200° C.

[0035] According to a further embodiment, the variable resistance element is made of the following materials: GeTe, and Al-doped Ge2Sb2Te5, i.e. Al x (Ge2Sb2Te5) 1-x (e.g., 0≦x≦0.3). The higher the value of x, the higher the critical temperature Tc, but the smoother the transition from the first state to the second state. The above-mentioned materials are examples of phase change materials.

[0036] According to a further embodiment, the transition of the variable resistance element from the first state to the second state is reversible. This means that after switching from the first state to the second state due to an increase in temperature, the variable resistance element switches back to the first state, for example automatically, when starting from the second state the temperature drops below a critical temperature Tc. This can be advantageous since the semiconductor device can be operated normally after a short circuit. For example, the resistance element may include or be made of one or more vanadium oxide-based materials to achieve reversibility.

[0037] According to a further embodiment, the transition of the variable resistance element from the first state to the second state is irreversible. This means that after switching from the first state to the second state due to an increase in temperature, the variable resistance element does not automatically switch back to the first state when starting from the second state the temperature drops below a critical temperature. For example, it remains in the second state or switches to a third state different from the first state. The third state may be a state in which the variable resistance element still behaves like a conductor. For example, the resistance element may include or be made of one or more titanium oxide-based materials to achieve irreversibility.

[0038] According to a further embodiment, the semiconductor device is a power semiconductor device. For example, the operating voltage of the semiconductor device is at least 500V, or at least 1000V, or at least 3000V, or at least 6000V. The operating voltage may be the voltage between the first electrode and the second electrode in normal operation of the semiconductor device.

[0039] According to a further embodiment, the semiconductor device is or comprises an insulated gate bipolar transistor (IGBT for short). The semiconductor device may comprise or be a reverse-conducting insulated gate bipolar transistor (RC-IGBT for short), for example a bi-mode insulated gate transistor (BIGT for short).

[0040] According to a further embodiment, the semiconductor device is or comprises a MOSFET.

[0041] According to a further embodiment, the semiconductor device is or comprises a thyristor, for example an IGCT or a GTO.

[0042] Next, a method for operating a semiconductor device is defined. For example, the method operates a semiconductor device according to any one of the embodiments described herein. Thus, all features disclosed in relation to the semiconductor device are also disclosed in relation to the method, and vice versa.

[0043] According to one embodiment, a method for operating a semiconductor device includes: operating the semiconductor device with the variable resistance element in the first state until a short circuit appears in the semiconductor device which causes the temperature of the variable resistance element to rise above a critical temperature Tc; switching the variable resistance element from a first state to a second state; conducting a current between the semiconductor body and the gate electrode through the variable resistance element in the second state; Includes.

[0044] Operating the semiconductor device having the variable resistance element in the first state may include applying a voltage difference between the first electrode and the gate electrode and / or injecting a current through the first electrode. A short circuit may appear in the cut-off state of the semiconductor device. The switching from the first state to the second state may be automatic or may be triggered when the temperature rises above a critical temperature. Directing a current through the variable resistance element may occur automatically when the variable resistance element is in the second state. For example, a voltage difference between the first electrode and the gate electrode causes a current to flow automatically through the variable resistance element when in the second state.

[0045] In the following, the semiconductor device will be described in more detail based on an exemplary embodiment with reference to the drawings. The attached drawings are included to provide further understanding. In the drawings, elements of the same structure and / or function can be referred to by the same reference numerals. It should be understood that the embodiments shown in the drawings are representations for illustration purposes and are not necessarily drawn to scale. Insofar as elements or components in different drawings correspond to each other in terms of their functions, their description will not be repeated in each of the following drawings. For clarity, for some elements, corresponding reference numerals may not be shown in all drawings. [Brief description of the drawings]

[0046] [Figure 1] 1 illustrates a first exemplary embodiment of a semiconductor device in cross-sectional view. [Diagram 2] A second exemplary embodiment of a semiconductor device is illustrated in various figures. [Diagram 3] A second exemplary embodiment of a semiconductor device is illustrated in the various figures. [Figure 4] A second exemplary embodiment of a semiconductor device is illustrated in various figures. [Diagram 5] 4 shows measurements of a phase change material. [Figure 6] 1 illustrates a flow chart of an exemplary embodiment of a method for operating a semiconductor device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] The first exemplary embodiment of a semiconductor device 100 of Fig. 1 comprises a semiconductor body 1, which is for example based on silicon. On the top surface of the semiconductor body 1 a first electrode 2 and a gate electrode 3 are arranged. The gate electrode 3 is separated from the semiconductor body 1 by an insulating material 9, which for example comprises or consists of SiO2. A variable resistance element 4 extends from the gate electrode 3 through the insulating material 9 into the semiconductor body 1. In a lateral direction parallel to the main plane of extent of the semiconductor body 1, the variable resistance element 4 is surrounded, for example completely, by the insulating material 9.

[0048] The variable resistance element 4 is in direct electrical contact with the gate electrode 3 and in indirect electrical contact with the first electrode 2 via the semiconductor material of the semiconductor body 1 .

[0049] The variable resistance element 4 includes at least two states. In a first state, the variable resistance element 4 acts or behaves like an electrical insulator to inhibit or prevent a current flow between the first electrode 2 and the gate electrode 3. When the variable resistance element 4 is heated above a critical temperature Tc, the variable resistance element 4 transitions from the first state to a second state, in which the variable resistance element 4 acts or behaves like a conductor to allow a current flow between the first electrode 2 and the gate electrode 3 through the variable resistance element 4. For example, the transition occurs automatically.

[0050] Typically, a short circuit in a semiconductor device leads to a rapid temperature rise. Such a short circuit occurs when the voltage between the first electrode 2 and the gate electrode 3 inadvertently exceeds the threshold voltage V thThis may occur if the temperature rises above 100° C. The variable resistance element 4 is configured to recognize such a short circuit based on a sudden temperature rise and to react to this short circuit by providing a current path between the first electrode 2 and the gate electrode 3. A current flows from the first electrode 2 to the gate electrode 3 or vice versa, reducing the voltage difference between the first electrode 2 and the gate electrode 3, and the short circuit can be stopped. That is, the variable resistance element 4 automatically detects the short circuit and automatically switches off the short circuit. The current path provided by the variable resistance element 4 in the second state can connect the gate electrode to ground.

[0051] The dielectric constant of the material of the variable resistance element 4 is selected, for example, to take into account possible effects on the capacitance between the gate electrode 3 and the first electrode 2. For example, the dielectric constant of the material of the variable resistance element 4 is selected to be equal to or less than the dielectric constant of the insulating material 9. The variable resistance element 4 may include one or more of GeTe and Al-doped Ge2Sb2Te5, or may consist of one or more of GeTe and Al-doped Ge2Sb2Te5.

[0052] In a second exemplary embodiment of the semiconductor device 100 of Figures 2 to 4, the semiconductor device 100 is realized as a reverse conducting insulated gate bipolar transistor, or RC-IGBT for short. Figure 2 is thus shown in a cross-sectional view. Figure 4 shows the RC-IGBT 1000 in a top view of the emitter surface 101 of the RC-IGBT 100. Figure 3 shows the boxed portion of Figure 2 in more detail.

[0053] The RC-IGBT 100 comprises a semiconductor body 1 having a base layer 10, a buffer layer 11 and a collector layer 12. The buffer layer 10 and the base layer 11 are, for example, doped n-type. For example, the doping concentration in the buffer layer 11 is greater than the doping concentration in the base layer 10. The base layer 10 may be thicker than the buffer layer 11. Furthermore, the base layer 10 and / or the buffer layer 11 may be thicker than the collector layer 12 of the semiconductor body 1. The collector layer 12 comprises regions of different doping types, i.e. p-type doped regions and n-type doped regions. The collector layer 12 forms a collector surface 102 of the RC-IGBT 100. A collector electrode 5 is arranged on top of the collector surface 102 and is in electrical contact with the collector surface 102. The collector electrode 5 consists of, for example, a metal.

[0054] At the emitter surface 101 opposite the collector surface 102, the semiconductor body 1 comprises a number of well regions 14 (for better explanation, see FIG. 3). The well regions 14 are doped, for example, p-type. In the well regions 14, emitter regions 13, doped, for example, n-type, are embedded. On top of the emitter surface 101, a first or emitter electrode 2 is arranged and is in electrical contact with the emitter regions 13. Furthermore, a gate electrode 3 is arranged on the emitter surface 101 and is insulated from the semiconductor body 1 by an insulating material 9. The emitter electrode 2 and the gate electrode 3 are, for example, made of metal.

[0055] In an edge region of the RC-IGBT 100, the gate electrode 2 is electrically connected to a variable resistance element 4. The variable resistance element 4 is further connected to the semiconductor body 1. The resistance element 4 may be the variable resistance element 4 of the first exemplary embodiment, for example in terms of material. As soon as the variable resistance element 4 switches from a first state to a second state, a current can flow between the emitter electrode 2 and the gate electrode 3 via the variable resistance element 4.

[0056] 4, the RC-IGBT 100 is shown in a top view of the emitter surface 101. As can be seen, the gate electrode 3 comprises a gate pad terminal 30 at the corner of the device 100, and a gate runner 31. The gate runner 31 extends along the edge of the RC-IGBT 100 and laterally surrounds the emitter electrode 2 in a frame-like manner.

[0057] In the region of the gate pad terminal 30 a first variable resistance element 4 is arranged. This variable resistance element 4 is shown by a dashed line since in practice it is hidden below the gate pad terminal 30. Along the gate runner 31 further variable resistance elements 4 are arranged, which are also hidden in practice and are shown by dashed ellipses. The further variable resistance elements 4 are, for example, uniformly distributed along the gate runner 31.

[0058] Arranging one variable resistance element 4 below the gate pad terminal 30 is advantageous because this is the area where external electrical contacts are usually realized and any unintended large voltage drops between the gate electrode 3 and the emitter electrode 2 that may lead to a short circuit will first appear in the area of ​​the gate pad terminal 30. The variable resistance element 4 in this area can therefore react particularly quickly in the event of a short circuit.

[0059] FIG. 5 is a graph of the Al-doped Ge2Sb2Te5 films taken from Wang et al., Improved thermal and electrical properties of Al-doped Ge2Sb2Te5 films for phase-change random access memory, Journal of Physics D Applied Physics, 2012, DOI:10.1088 / 0022-3727 / 45 / 37 / 375302, the disclosure of which is incorporated herein by reference. x (Ge2Sb2Te5) 1-x3 shows the results of measuring the sheet resistance of Al. The temperature is shown on the x-axis (unit: °C). The sheet resistance is shown on the y-axis (unit: Ω / □). A total of four measurement curves are shown, i.e., for various values ​​of x (x=0, x=0.1443, x=0.2173, x=0.2319). Before the sheet resistance decreases, the material is amorphous, and after that, the material is crystalline. Al x (Ge2Sb2Te5) 1-x is a phase change material. As can be seen in Figure 5, at x = 0, the material has a sharp transition from an insulator to a conductor at Tc ≈ 170 °C. The larger the Al contribution, the smoother the transition and the higher the critical temperature Tc.

[0060] Figure 6 shows a flow chart of an exemplary embodiment of a method for operating a semiconductor device. In step S1 of the method, a semiconductor device, for example one of Figures 1 to 4, is operated with the variable resistance element in a first state. This is done so that or until a short circuit appears in the semiconductor device. The short circuit causes the temperature of the variable resistance element to rise above a critical temperature Tc.

[0061] In a further step S2, the variable resistance element switches from the first state to the second state, which may occur automatically upon an increase above a critical temperature Tc.

[0062] Then, in step S3, a current flows between the semiconductor body and the gate electrode through the variable resistance element in the second state, which may also occur automatically, for example, as long as a voltage difference exists between the first electrode and the gate electrode.

[0063] 1-4 and 6 above represent exemplary embodiments of the improved semiconductor devices and methods for operating the semiconductor devices, and therefore, they do not constitute an exhaustive list of all embodiments of the improved semiconductor devices and methods. Actual semiconductor devices and methods may differ from the illustrated embodiments, for example, with respect to layout. [Explanation of symbols]

[0064] Reference sign 1. Semiconductor body 2 First electrode 3. Gate electrode 4 Variable resistance element 5 Second electrode / collector electrode 9 Electrical insulating materials 10 Base Layer 11 Buffer layer 12 Collector layer 30 Gate pad terminal 31 Gate Runner 100 Semiconductor Devices 101 Emitter surface 102 Collector surface S1~S2 Method steps

Claims

1. A semiconductor device (100), a semiconductor body (1), a first electrode (2), a gate electrode (3), A plurality of variable resistance elements (4) arranged at different positions of the semiconductor device (100) and spaced apart from each other; It is equipped with the variable resistance element (4) is electrically connected to the gate electrode (3) and the first electrode (2); Each of the variable resistance elements (4) has at least a first and a second state; In the first state, the variable resistance element (4) acts as an electrical insulator to prevent current from flowing from the first electrode (2) to the gate electrode (3) through the variable resistance element (4) or vice versa; in the second state, the variable resistance element (4) acts as a conductor to allow current to flow from the first electrode (2) to the gate electrode (3) through the variable resistance element (4) or vice versa; the variable resistance element (4) is configured to effect a smooth transition from the first state to the second state when the temperature of the variable resistance element (4) rises above a critical temperature Tc, such that a temperature range ΔT over which the transition from the first state to the second state occurs is at least 50° C.; A semiconductor device (100) characterized in that a variable resistance element (4) is located in a region below a gate pad terminal (30) of the gate electrode (3) of the semiconductor device (100), and multiple variable resistance elements (4) are arranged below a gate runner (31) of the gate electrode (3).

2. The variable resistance element (4) comprises a phase change material The semiconductor device (100) of claim 1.

3. The conductivity of the variable resistance element (4) in the second state is at least 100 times the conductivity of the variable resistance element (4) in the first state. The semiconductor device (100) of claim 1 or 2.

4. The temperature range ΔT over which the transition from the first state to the second state occurs is at least 100° C. The semiconductor device (100) of claim 1 or 2.

5. The critical temperature Tc is at least 50° C. higher than the normal operating temperature of the semiconductor device (100). The semiconductor device (100) of claim 1 or 2.

6. The variable resistance element (4) is made of the following materials: GeTe and Al-doped Ge ２ Sb ２ Te ５ It includes or consists of one or more of The semiconductor device (100) of claim 1 or 2.

7. The semiconductor device is a power semiconductor device. The semiconductor device (100) of claim 1 or 2.

8. The semiconductor device (100) comprises an insulated gate bipolar transistor and / or a MOSFET The semiconductor device (100) of claim 1 or 2.

9. A method for operating a semiconductor device (100) according to claim 1, comprising: - operating the semiconductor device (100) with the variable resistance element (4) in the first state until a short circuit appears in the semiconductor device (100) that raises the temperature of the variable resistance element (4) above the critical temperature Tc; - switching the variable resistance element (4) from the first state to the second state; conducting a current between the semiconductor body (1) and the gate electrode (3) through the variable resistance element (4) in the second state; The method includes:

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