Semiconductor die with vertical transistor device

Abstract

The present disclosure relates to a semiconductor die with a vertical transistor device, comprising: a transistor device (10) comprising a source region (11) located at a first side (15.1) of a semiconductor body (15), a drain region (12) located at a second side (15.2) of the semiconductor body (15), a trench (25) extending from the first side (15.1) into the semiconductor body (15) and having an elongated lateral extension, a first trench electrode (30) extending from the first side (15.1) into the semiconductor body (15), and a second trench electrode (40) extending from the second side (15.2) into the semiconductor body (15), a first trench electrode (30) for channel creation or field shaping, having an elongated lateral extension (35) and being seated in the trench (25), and a control electrode contactor (31) contacting the first trench electrode (30) from a first side (15.1) of the semiconductor body (15) for applying an electrical potential, said control electrode contactor (31) being seated in a first lateral position (41); and a sensing electrode contactor (32) contacting the first trench electrode (30) from a first side (15.1) of the semiconductor body (15) for sensing a voltage from the first trench electrode (30), where the sensing electrode contactor (32) is seated at a second lateral position (42) spaced apart from the first lateral position (41).

Description

Technical Field

[0001] The present disclosure relates to a semiconductor die having a semiconductor body including a vertical transistor arrangement. Background Art

[0002] The vertical transistor device may have a source region on a first side and a drain region on a second side of the semiconductor body. A trench extends from the first side into the semiconductor body. In the trench, a first trench electrode is arranged, which can, for example, be a gate electrode for channel creation or a field electrode for field shaping. The first trench electrode is contacted via a control electrode contact to apply a corresponding potential to the first trench electrode, such as a gate potential or a source potential. For example, the gate electrode and a field electrode arranged below the gate electrode can both be arranged in the same trench. Summary of the invention

[0003] The object of the present application is to provide an advantageous semiconductor die having a vertical transistor arrangement.

[0004] In a semiconductor die as claimed in claim 1, in addition to the control electrode contact, a sensing electrode contact is provided which contacts the first trench electrode from the first side of the semiconductor body. It is arranged at a second lateral position, which is spaced apart from the first lateral position, at which the control electrode contact is arranged. Via the sensing electrode contact, the first trench electrode can be used, for example, to sense variations of the drain potential in a capacitive manner. In other words, the first trench electrode can be used as a first capacitor electrode, which together with a second capacitor electrode arranged at the second side of the semiconductor body (in particular, in the case of a common drain back side, together with the drain region) forms a capacitor. Therein, an "active" electrode which is already part of the vertical device is used to sense back side potentials or transients, which can, for example, allow an area reduction compared to a separate sensing electrode located next to the transistor device.

[0005] The variation of the back surface potential can be in particular a variation of the drain-to-source voltage, and fast transients can be associated with potential failure mechanisms such as dynamic avalanche and dynamic return-on. Such an event can, for example, occur when the drain-to-source voltage varies too fast, triggering, for example, parasitic dynamic currents (which can lead to failure or degradation). The present arrangement can allow such fast transients to be sensed, and countermeasures can therefore be implemented internally or externally, as described in detail below. The internal resistance of the first trench electrode (e.g., its resistance between the control contactor and the sense contactor) can contribute to or determine the difference between the applied control potential and the sensed potential and the time delay between the back surface potential and the sensed voltage.

[0006] Throughout the present disclosure and in the dependent claims, specific embodiments and features are presented. Thus, independent of the specific claim category, individual features will be disclosed, and the present disclosure relates to equipment and device aspects, but also to method and use aspects. If, for example, a tube core manufactured or used in a specific way is described, this is also a disclosure of the corresponding manufacturing process or use, and vice versa. In general, the scheme of the present application is to provide a vertical device with an active electrode in a groove, and use the active electrode of the device as a sensing electrode (first groove electrode). The first groove electrode can be bound to the potential required for use in the device via a control electrode contact, and the sensing electrode contact placed at a certain distance from it allows the detection of changes caused by the capacitive coupling of the first groove electrode.

[0007] The trench in which the first trench electrode is placed can be arranged in the active area of ​​the vertical device. It can, for example, extend into the main region of the vertical device, and / or extend into the drift region of the vertical device. The sensing electrode (that is, the first trench electrode) placed in the trench can, for example, be used for field shaping in the device, for example, being placed laterally next to the drift region of the vertical device for field shaping in the drift region. Alternatively, it can be placed in the trench and laterally next to the main region of the vertical device, that is, capacitively coupled to such a main region so that the channel of the vertical device is formed there by the first trench electrode. In other words, the sensing electrode can be a gate electrode or field electrode of the vertical device in particular. The vertical device is configured for vertical current flow in operation between its source region and drain region, and the sensing electrode can, for example, control such current flow by channel creation or, for example, shape the electric field during current flow and / or in the blocking state of the vertical device.

[0008] The source and drain regions of a vertical device are placed on two vertically opposite sides of a semiconductor body, where the "first side" can also be referred to as the front side and the "second side" can also be referred to as the back side. In the body region of the device, a channel can be formed by applying a voltage to the gate electrode of the vertical device. Although the transistor device as a whole is considered "vertical" due to its vertically opposite source and drain regions, a lateral channel is generally conceivable, for example, in the case where the gate region is placed on top of the body region (and the source region is laterally located next to the latter). The gate electrode of the vertical device is not necessarily placed in the trench, the field electrode can still be arranged in the trench and can be the "active" electrode of the device for sensing. However, in particular, the gate region is placed laterally next to the body region, and the channel extends in a vertical direction next to the trench, as described below.

[0009] The semiconductor body can include: a substrate; and one or more epitaxial layers, which can particularly form a first side of the semiconductor body. The trench extends from the first side into the semiconductor body, for example, into the epitaxial layer; its lower end can particularly be located above the substrate, for example, in a drift region formed in the epitaxial layer. Laterally, the trench and the first trench electrode have an elongated extension, and the lateral length is a multiple of the vertical depth. In the vertical top view, the trench and the first trench electrode can particularly extend as a straight line ("stripe shape"), and the transistor device includes, for example, a plurality of device primitives, each device primitive having a stripe shape, and the stripes are arranged as parallel lines. Alternatively, a matrix-like primitive arrangement is also possible, the primitive having, for example, a polygonal shape, such as a square primitive. In this case, the trenches can form a grid, in which the gate electrodes arranged therein can still be used for sensing, as described below.

[0010] "Vertical" or "in the vertical direction" refers to a vertical direction, which is, for example, perpendicular to the surface of the die (for example, the surface of the substrate or an epitaxial layer formed on the substrate). "Above" means aligned with the first side of the die in the vertical direction and closer to the first side of the die, and "below" means aligned with the second side in the vertical direction and closer to the second side. "Laterally" or "in the lateral direction" refers to a lateral direction perpendicular to the vertical direction, in which direction, for example, the die area is taken. On the first side of the semiconductor body, an insulating layer can be arranged, for example made of silicon oxide or borophosphosilicate glass (BPSG). Above, one or more metallization layers can be formed. The sensing and / or control electrode contacts can in particular extend through the insulating layer, for example for further connection and wiring in the metallization layer.

[0011] In an embodiment, the control electrode contactor is placed in the first half of the lateral extension of the first groove electrode, and the sensing electrode contactor is placed in the second half thereof. Alternatively or in addition, the minimum lateral distance between the control electrode contactor and the sensing electrode contactor can be, for example, at least 10%, 30%, 50%, 70% or 90% of the lateral extension of the first groove electrode. In absolute values, the lateral distance can be, for example, 0.1mm, 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm or 5mm, which can also depend on the die size. Typically, when the "distance" between two elements is considered, it is considered to be the minimum distance between these elements in the corresponding direction (rather than being considered as a center-to-center distance), where the lateral extension of the first groove electrode and the corresponding distance are obtained in the first lateral direction. Independent of the implementation or manner of detailed measurement, a certain lateral distance between the contacts can, for example, allow the required time delay and / or potential difference between the contacts.

[0012] In particular, the control electrode contact can be placed at a first lateral end of the first groove electrode, and / or the sensing electrode contact can be placed at a second lateral end thereof, the first end and the second end being laterally opposite to each other. "Placed at the lateral end" means, for example, being arranged such that the maximum distance relative to the respective end does not exceed 10%, in particular not more than 5%, of the lateral extension of the first groove electrode. Seen in a vertical top view, the first groove electrode can, for example, have a stripe shape (see above), wherein the electrode contacts are placed at opposite ends of the stripe.

[0013] In an embodiment, further electrode contacts which do not contact the first trench electrode are arranged laterally between the control electrode contact and the sensing electrode contact. In other words, over the entire distance between the contacts, the first trench electrode can be covered by an uninterrupted insulating layer, such as an oxide layer, such as silicon oxide. In the case of a field electrode for sensing (see below), such an insulating layer can, for example, separate it from the gate electrode above.

[0014] As discussed above, the gate region (including the gate electrode and the gate dielectric) of the vertical device can in particular be arranged laterally next to the body region, the gate electrode being placed in the trench. In a particular embodiment, such a gate electrode is used as a first trench electrode, the gate potential being applied via the control electrode contact, and the transients being sensed via the sense electrode contact. Independently of whether the gate electrode forms a stripe or a grid pattern, it has an elongated extension in at least one lateral direction (the first lateral direction) in which the control and sense electrode contacts are placed with a lateral distance between them.

[0015] Regardless of whether the channel has a lateral extension or a vertical extension, and regardless of the specific cell layout (stripes or grid), the vertical transistor device can in particular include a drift region, which is made of the same doping type but has a lower doping concentration than the drain region. With reference to the source and drain regions made of the first doping type and the body region made of the second doping type, the drift region can also be made of the first doping type. In the vertical direction, for example, in an epitaxial layer on a substrate, it can be placed between the body region and the drain region. In an exemplary embodiment, the first type is n-type and the second type is p-type. In particular, the device can include a field electrode extending into a trench in the drift region. The field electrode is capacitively coupled to the drift region via a field dielectric, which allows field shaping by applying a potential to the field electrode (e.g., a gate potential or in particular a source potential). Typically, the field electrode can have a thorny shape, for example in the case of a grid-like gate pattern (with a thorny field electrode in each cell), wherein, for example, a portion of the grid-like gate pattern can be used for sensing.

[0016] However, in a particular embodiment, an elongated field electrode is placed in a trench having an elongated lateral extension, in particular having a stripe shape as seen in the top view. In particular, the elongated field electrode is used for sensing and serves as a first trench electrode. Thus, the field electrode is contacted via the sensing electrode contact in addition to the control electrode contact for applying a potential for field shaping. Since the field electrode extends in the drift region, it can be relatively close to the back side or drain region, which can be beneficial, for example, when sensing transients in a capacitive manner.

[0017] In addition to the elongated field electrodes in the trenches, the vertical device can also include an elongated gate electrode in the trench, typically in a separate trench next to the field electrode trench, or in particular above the field electrode in the same trench. These electrodes can be electrically isolated from each other by an insulating layer placed in the trench in the vertical direction. In the case of a device with an elongated field electrode and an elongated gate electrode, one or both of these electrodes can be used for sensing. In the latter case, the field electrode can be a "first trench electrode" and the gate electrode can be used as a "second trench electrode", which is contacted by a sensing electrode contact in addition to a control electrode contact for applying a gate potential. Generally, any design or feature described for the first trench electrode will also be disclosed for the second trench electrode.

[0018] Typically, the sensing functionality can be used or processed externally, for example in an external control circuit for the vertical device, or even independently of the actual device operation, for example for evaluation purposes. In particular, however, the controllable clamping device is integrated in the same die as the vertical device and connected to the vertical device. The clamping device can have a control terminal and a load terminal, wherein a voltage applied to the control terminal can, for example, control a current flow between the load terminals. By connecting a sensing electrode contact to the control terminal of the clamping device, a change in potential sensed via a trench electrode of the vertical device, for example due to backside transients, can be used to switch or trigger the controllable clamping device.

[0019] The clamping device can be connected, for example, in case the load contact of the clamping device is located between the drain and gate contacts of the vertical device or between the gate and source contacts of the vertical device, that is, connected as a pull-down device. In case the gate-to-source voltage of the vertical device would increase above the threshold voltage of the vertical device, an induced turn-on could result, while the device should actually be in the off state. This can be prevented by a pull-down device, which can be in the on state (conducting) when the vertical device is off, or which can be triggered during fast switching transients that would turn on the vertical device (and cause, for example, losses and potential device failure).

[0020] In a particular embodiment, a controllable clamping device is connected in parallel to the vertical device. One load contactor of the clamping device is connected to the vertical device source region / contactor and the other load contactor is connected to the drain region / contactor of the vertical device. In other words, the controllable clamping device is used as a shunt device. In general, an advantage of a trench electrode suitable for sensing fast transients can be that it is not activated, for example, in static or slow switching events. Considering the shunt device, this can be particularly beneficial because it does not reduce the static breakdown voltage as a result. Vice versa, it can protect the vertical device from fast switching events even if the drain-to-source voltage is much lower than the static breakdown voltage.

[0021] In an embodiment, the controllable clamping device is a transistor device, a MOS gate-controlled diode or a field electrode-controlled diode. By applying a voltage to the field electrode of the field electrode-controlled diode, its breakdown voltage can be adjusted. Therefore, its field electrode is a control terminal of the sensing electrode contact connected to the trench electrode of the vertical device. When the sensing voltage increases to a voltage higher than the selected voltage (e.g., adjusted to be slightly higher than 0V), the diode enters avalanche. In order to optimize the diode to be activated only during fast transients and not activated under static / slow switching, it can have a different breakdown voltage and field plate voltage correlation compared to the vertical device in particular. The field electrode-controlled diode can, for example, be implemented as a design variation, for example, as a FET without a gate electrode. However, process variations such as local n-implantation of the clamping device and / or a clamping device trench with different geometries and / or oxides are also conceivable.

[0022] In the case of a clamp FET, its gate electrode is the control terminal of a sense electrode contact connected to the trench electrode of the vertical device. When the sensed voltage exceeds a threshold voltage, the clamp FET starts to conduct, e.g., as a shunt device connecting the source and drain of the vertical device. The shunt FET can have the same or different threshold voltage compared to the vertical transistor, and its threshold voltage can be tuned, e.g., by design or process adaptation (additional body implants for the shunt FET, different contactor width / depth, additional source implants, different gate oxide thickness, or any other adaptation for achieving a variation of the threshold voltage).

[0023] Independently of the specific type of controllable clamping device, the connection between its control terminal and the sensing electrode contact can in particular be formed via a metal pad on the first side of the semiconductor body, the metal being for example deposited on an insulating layer of the first side. The metal pad can for example be formed in the same metallization layer as the source metal and / or the gate metal of the vertical device, the latter having for example one or in particular two metallization layers. In other words, the wiring of the clamping device and the vertical device does not for example require additional metallization layers. Laterally, the respective metal pad can for example be arranged in a rather central position in the case of a central sensing bus line or in particular in an edge portion of the die, for example together with a gate metal pad or additionally in the case of no edge gate pad.

[0024] The control terminal of the clamping device can be connected to the sense is connected to the source region of the vertical device. In an embodiment, the resistor R sense is defined by the internal resistance of the first trench electrode, that is to say the resistance taken between the control electrode contact and the sense electrode contact. Alternatively or additionally, the control terminal of the clamping device is connected by means of a capacitor C sense Capacitively coupled to the drain region of the vertical device, where the capacitor C sense It can in particular be defined by a distributed capacitance between the first trench electrode and the drain, which, in particular in the case of a field electrode used for sensing, extends laterally across the elongated trench between the control electrode contact and the sense electrode contact.

[0025] In an embodiment, the die comprises an additional transistor device connected in parallel to the (first) vertical transistor device. The additional transistor device can in particular also be a vertical device, and the gate electrodes of these devices can be connected to each other, for example by a gate runner. In other words, the transistor device can be a device primitive of a common vertical transistor device, the primitive having, for example, a stripe or grid pattern (see above for details). The first vertical transistor device comprises a trench electrode with a sensing electrode contact and is used for sensing, while the additional transistor device can be provided without a sensing electrode contact. Considering the entire primitive field of the devices connected in parallel, the first vertical device can, for example, have a ratio between 10%-90%, and the additional device can, for example, have a complementary ratio between 90%-10% (therefore, the relationship between the first device and the additional device can, for example, be 10-90, 30-70, 50-50, 70-30, 90-10).

[0026] Independently of these details, the gate electrodes of these transistor devices / device primitives (that is, the first device and the additional device) can be arranged in separate trenches (e.g. trenches with straight extensions arranged parallel to each other), that is, arranged as stripe-shaped primitives. The stripe-shaped device primitives can, for example, have their respective length extensions in a first lateral direction and be arranged translationally symmetrically to each other in a second lateral direction perpendicular to the first lateral direction. In a particular embodiment, the control terminal (gate electrode or field plate, see above) of the controllable clamping device is also arranged in a separate trench, for example in another straight trench arranged parallel to the other trenches.

[0027] In an embodiment, the transistor device and the additional transistor device have a grid-shaped gate structure, the gate electrodes cross each other, some gate electrodes extend in a first lateral direction and other gate electrodes extend in a second lateral direction. By definition, the transistor device and the additional transistor device, which can respectively include a plurality of transistor device primitives arranged in a grid pattern, are placed next to each other in the second lateral direction. Then, in particular, at least some of the gate electrodes extending in the second lateral direction can be interrupted between the additional transistor device and the transistor device. The trench can extend continuously, for example be filled with an insulating material to form the interruption, or can be so interrupted by a respectively adapted etching mask.

[0028] The present application also relates to a package in which the semiconductor die disclosed herein is housed. The package can be a metal, plastic, glass or ceramic housing, which can, for example, allow further mounting and connection on a board. The package can typically include a plurality of pins, for example for source and drain connections of a vertical device, and typically also for its gate connection. In a particular embodiment, for example in addition to the aforementioned pins, the package also includes sense pins, wherein the sense pins are electrically connected to sense electrode contacts of the die. Such electrical connections can be formed inside the package, for example by bonding wires or clips, etc. For example, as an alternative to the internal circuits discussed above, or in addition to the internal circuits discussed above, the sense pins can allow external evaluation of sensed back-side transients.

[0029] The present application also relates to a method of using a die disclosed herein or a package with a corresponding die, wherein via a control electrode contact a potential is applied to a first trench electrode. This can for example be a gate or source potential, see above. In addition, via a sense electrode contact a potential is sensed, for example in order to sense back-side transients. The sensed potential can be used externally and / or in particular applied to a control terminal of a controllable clamping device, which can be provided separately or can in particular be integrated in the same die.

[0030] The present application also relates to a method of manufacturing a semiconductor die or package, said method comprising the formation of a transistor arrangement and the formation of a sensing electrode contact. The latter can in particular be formed in the same process step as the control electrode contact. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In the following, a semiconductor die having a vertical transistor arrangement as well as use and production are explained in more detail with the aid of exemplary embodiments, wherein individual features can also be relevant in different combinations.

[0032] Figure 1 shows a schematic cross section through a gate electrode and a field electrode and illustrates the use as a sensing electrode;

[0033] Figure 2 A cross section through a transistor device is shown, with the cross section plane perpendicular to Figure 1 ;

[0034] Figure 3 A circuit diagram illustrating the wiring of a transistor device having a monolithically integrated shunt FET is shown;

[0035] Figure 4 Showing a primitive with a stripe shape Figure 3 The layout of the wiring implementation;

[0036] Figure 5 Another circuit diagram is shown which illustrates the wiring of the gate electrode of a vertical device for sensing in combination with a field electrode controlled diode as a shunt device;

[0037] Figure 6 Showing a primitive with a stripe shape Figure 5 The layout of the wiring implementation;

[0038] Figure 7 is a schematic top view illustrating a possible implementation of a gate sensing structure in the case of a cell grid having polygonal transistor cells;

[0039] Figure 8a A flow chart illustrating some steps of using a die is shown;

[0040] Figure 8b Some steps of manufacturing the die are shown;

[0041] Fig. 9 Shown as Figure 5 Comparison of the breakdown voltage dependence of the field plate voltage for the vertical device and the field electrode controlled diode discussed in . DETAILED DESCRIPTION

[0042] Figure 11 shows a cross-sectional view through a portion of a semiconductor die 1 having a semiconductor body 15, in which a transistor device 10 is formed. The transistor device 10 has a vertical design, its source region (at Figure 1 Not visible in , see Figure 2 ) is arranged at a first side 15.1 of the semiconductor body 15, and its drain region 12 is arranged at a vertically opposite second side 15.2 of the semiconductor body 15. The transistor device 10 comprises a trench 25, which extends from the first side 15.1 into the semiconductor body 15. In the trench 25, a gate electrode 26 and a field electrode 27 are arranged. As discussed above, in some embodiments, only one of the gate electrode 26 or the field electrode 27 is arranged in the trench 25. Typically, the gate electrode 26 is used for channel creation from the source region to the drain region 12 of the semiconductor body 15, and the field electrode 27 is used for field shaping (such as field shaping of the electric field within the source region, the body region and / or the drift region of the semiconductor body 15). Each of these electrodes 26, 27 is contacted via a respective control electrode contact 31, that is, the gate electrode 26 is contacted via a gate control electrode contact 31a, and the field electrode 27 is contacted via a field control electrode contact 31b. Via respective control electrode contacts 31 , potentials can be applied to the respective electrodes 26 , 27 , that is to say a gate potential is applied to the gate electrode 26 and, for example, a source potential is applied to the field electrode 27 .

[0043] In addition to the control electrode contact 31 arranged at the first lateral position 41, a corresponding sensing electrode contact 32 arranged at the second lateral position 42 is provided (the lateral position of the contact is only quoted for the gate electrode 26). Therefore, the corresponding electrode 26, 27 can not only be used for channel creation or field shaping, but also for sensing. In case of corresponding use of the gate electrode 26, it can be regarded as a "first trench electrode" 30 contacted by the sensing electrode contact 32 (in particular, the gate sensing electrode contact 32a). Due to the lateral distance between the control electrode contact 31 and the sensing electrode contact 32, the sensing resistor R sense_1 , the sensing electrode contact 32 is connected to the control electrode contact 31, and thus to the gate voltage. When the drain potential rises rapidly (fast transient), due to the capacitance C sense_1 Due to the capacitive coupling, the voltage can rise at the sensing electrode contactor 32, while the voltage at the control electrode contactor 31 is bound to the gate voltage. sense_1 is formed rather obliquely Figure 1 Behind or in front of the drawing plane (see Figure 2 for comparison), and therefore in Figure 1This is the capacitance between the gate and drain of the transistor device 10. The voltage rises at the sensing electrode contact 32 and can be used for external evaluation or for internal circuits, see below.

[0044] As an alternative to the gate electrode 26, or in addition to the gate electrode 26, the field electrode 27 can be used for sensing and is considered as a "first trench electrode" 30. Again, the lateral distance between the control electrode contact 31 and the sense electrode contact 32 gives the internal resistance R sense_2 As indicated for the field electrode 27 as an example, the control electrode contact 31 is arranged in the first half 35 . 2 of the lateral extension 35 of the trench electrode 30 , while the sense electrode contact 32 is arranged in the second half 35 . 1 thereof. sense_2 , the field electrode 27 is capacitively coupled to the drain region 12, so that the rise in the back surface potential can be capacitively picked up and trigger a voltage rise at the sensing electrode contact 32. Using the gate electrode 26 or the field electrode 27 for sensing can be an alternative (e.g. only one sensing electrode contact is provided), or they can be combined (where the field electrode 27 can be regarded as a "first trench electrode" and the gate electrode 26 as a "second trench electrode", both of which are used for sensing).

[0045] Figure 2 A cross-sectional view of a vertical device 10 is shown, the cross-sectional plane being perpendicular to the longitudinal direction of the trench 25. In general, in the present disclosure, similar reference numerals are used for similar elements or elements having similar functions and also always with reference to the description of other figures. The device 10 comprises a source region 11 at a first side 15.1 of a semiconductor body 15, with a body region 13 having a vertical channel region 13.1 being arranged below. Laterally alongside, a gate region 126 is arranged, comprising a gate electrode 26 and a gate dielectric 127, which capacitively couples the gate electrode 26 to the channel region 13.1.

[0046] In the same trench 25, a field electrode region 129 with a field electrode 27 and a field dielectric 128 is arranged. Via the field dielectric 128, the field electrode 27 is capacitively coupled to the drift region 14 of the device for field shaping. The drift region 14 has the same doping type as the drain region 12, but has a lower doping concentration. In the example shown, the source region 11, the drain region 12 and the drift region 14 are n-doped, and the body region 13 is p-doped.

[0047] Figure 3A circuit diagram is shown and illustrates the connections of the die 1 in the package 101 (shown schematically). Via the source pin 111 of the package 101, the source contact 11.1 of the device 10 can be contacted, via the drain pin 112, the drain contact 12.1 can be contacted and via the gate pin 116, the gate contact 26.1 can be contacted. In addition to the device 10, a controllable clamping device 50 is integrated in the die 1, that is, a clamping field effect transistor 60 in the example shown. It has a source contact 61 and a drain contact 62 and is connected as a shunt device, that is, in parallel with the vertical device 10. The control terminal 51 (that is, the gate contact of the shunt FET) is connected to the sense electrode contact 32b (see Figure 3 1 and is thus connected to the field electrode 27. The field electrode 27 is an electrode of the capacitor 130, the other electrode being formed by the drain region 12.

[0048] As discussed above, rapid changes in drain potential can be sensed via a rise in voltage at the sense electrode contact 32b, which switches the controllable clamping device 50 to a conducting state (see general description for details). The package 101 further comprises a sense pin 132, which is connected to the sense electrode contact of the first trench electrode 30. This can allow external evaluation and can be combined with the integrated clamping device 50, or can be an alternative to the integrated clamping device 50. Figure 3 In the circuit diagram, the resistor 85 is connected between the control terminal 51 and the source domain, and the resistance R of the resistor 85 is sense_2 Defined by the internal resistance of the first trench electrode 30 , see above.

[0049] Figure 4 A possible layout is illustrated in a vertical top view. The transistor device 10 with the first trench electrode 30 is arranged as a stripe-shaped primitive, with the trench 25 having an elongated extension. In the central part of the trench 25, the gate electrode 26 is visible, which in this embodiment is only contacted by the gate electrode control contact 31a, that is, not used for sensing. It is connected to the gate metal pad 226. Alternatively, a gate electrode 26 is placed below (and only in) the gate electrode 26. Figure 4 The field electrode 27 of the gate electrode 26 (visible at the edge of the trench in the gate electrode 26) is used as the first trench electrode 30, as described in detail above. The field electrode material 227 is exposed upwards at the two lateral sides of the gate electrode 26. There, contacts 31, 32 are formed, that is to say a control electrode contact 31 at the first end 30.1 of the first trench electrode 30 and a sense electrode contact 32 at the second end 30.2 of the first trench electrode 30. In the example shown, one further sense cell is connected in parallel, both of which are referenced with the number 10 (but only one of them is referenced in more detail).

[0050] The source region 11 and the body region 13 of the device 10 are connected to the source metal pad 211 via the body contact 213, see also Figure 2 301 . In addition, that is to say, via the control electrode contact 31, the field electrode of the device 10 is connected to the source metal pad 211. This schematic image is not necessarily drawn to scale, in particular, the actual transistor segment area (see the arrow of the reference numeral 10) can be significantly longer in a first lateral direction 301 (longitudinal direction) than what is shown here, which applies in particular to the area surrounded by the source pad 211. A second lateral direction 302 perpendicular thereto can also be referred to as a transverse direction.

[0051] Next to the transistor device 10 (sense FET) in the second lateral direction 302, an additional transistor device 100 is arranged. It comprises a plurality of stripe-shaped device cells 100.1-100.4, each device cell having a Figure 2 . In contrast, the gate and field electrodes of the additional transistor device 100 are only used for channel creation and field shaping, not for sensing. The device cells 100.1-100.4 are connected in parallel with each other and with the device 10 (sense FET), they have a common gate domain. Its source and body regions as well as its field plate are connected to the source metal pad 211 via respective contacts 327, 328.

[0052] The clamping field effect transistor 60 (shunt FET) is arranged on the other side of the sense FET, that is, at Figure 4 The control terminal 51 (gate electrode) of the clamping field effect transistor 60 is connected to the metal pad 70 through the corresponding contactor 251, and the metal pad 70 is also connected to the sensing electrode contactor 32. Figure 3 As discussed, that is, the source domain of clamping field effect transistor 60 is connected to source metal pad 211 via corresponding contact 261. In addition, the devices share a common drain backside.

[0053] Figure 5 A circuit diagram of another embodiment is shown, wherein the following description mainly highlights the differences. The gate electrode 26 is used for sensing and forms one electrode of the capacitor 130 (the gate electrode is used as the first trench electrode, see Figure 1 ). With resistance R sense_1 The resistor 85 is defined by the internal resistance of the gate electrode 26. The gate electrode 26 is connected to the control terminal 51 of the controllable clamping device 50 via the sensing electrode contact 32a. Figure 5 In the middle is the field electrode control diode 65.

[0054] Figure 6 The following diagram shows possible layouts and mainly highlights the Figure 4 The difference Figure 6 The setting corresponds to Figure 5 . The gate electrode 26 is used for sensing, and the field electrode control diode 65 is used as the controllable clamping device 50. The gate electrode 26 is the first trench electrode 30, and in addition to being connected to the gate metal pad 226 via the control electrode contact 31a, it is also connected to the metal pad 70 via the sensing electrode contact 32a. Via the contact 261, the metal pad 70 is connected to the control terminal of the controllable clamping device 50, that is, to the field electrode 165 of the field electrode control diode 65. The field electrode of the device 10 placed under the gate electrode 26 is connected to the source metal pad 211 via the field electrode control contact 31b, but with Figure 4 In contrast, none is contacted for sensing.

[0055] Although the above embodiment illustrates an implementation with a stripe-shaped primitive, in the case of a grid-shaped gate structure 300, that is, in Figure 7 The gate sensing scheme can also be implemented in the case of polygonal or particularly polygonal primitives as schematically illustrated in the figure. The gate electrodes 26.1 extending in the first lateral direction 301 and the gate electrodes 26.2 extending in the second lateral direction 302 cross each other and form a grid. The additional transistor device 100 includes a plurality of primitives formed in such a grid, which also applies to the transistor device 10 for sensing (which primitives are not referenced in detail). Between them, some of the gate electrodes 26.2 extending in the second lateral direction are interrupted. This can, for example, prevent the internal gate potential of the additional transistor device 100 from being affected by the gate sensing potential (because of the capacitive loading of the shunt element). The gate track 350 can, for example, extend in a U-shape around the additional transistor device 100, but leave one side of the sensing FET unconnected, as shown in the figure. There, a sensing electrode contact 31 can be provided (at Figure 7 different possible locations indicated in ).

[0056] Figure 8a Some steps of using the device or die disclosed herein are illustrated in a flow chart. In addition to applying 180 a potential to the first trench electrode, via a sense electrode contact, the potential is sensed 181. Additionally, the sensed potential can be applied 182 to a control terminal of a controllable clamping device, see above.

[0057] Figure 8b Some manufacturing steps are illustrated. In addition to forming 185 the transistor device, a sense electrode contact is formed 186. In process terms this can be integrated, for example making the sense electrode contact during forming 185 the transistor device.

[0058] Fig. 9 The diagram of shows the dependence of the breakdown voltage (BV) on the y-axis on the field plate voltage (FPV) on the x-axis. Thereby, a transistor device (dashed line) and a field electrode controlled diode (continuous line) are compared. The field electrode controlled diode can have a higher breakdown voltage (static breakdown voltage) for FPV=0V, but has a faster decay when the field plate voltage increases. Therefore, when the field plate voltage rises during a dynamic avalanche, the corresponding shunt diode can take over the avalanche current.

Claims

1. A semiconductor die (1) having a semiconductor body (15), the semiconductor die (1) comprising: A transistor device (10) comprising: a source region (11) located on a first side (15.1) of the semiconductor body (15), a drain region (12) located on a second side (15.2) of the semiconductor body (15), a trench (25) extending from the first side (15.1) into the semiconductor body (15) and having an elongated lateral extension, a first trench electrode (30), for channel creation or field shaping, having an elongated lateral extension (35) and being disposed in the trench (25), and a control electrode contact (31) contacting the first trench electrode (30) from the first side (15.1) of the semiconductor body (15) for applying an electrical potential, the control electrode contact (31) being arranged at a first lateral position (41); and A sensing electrode contact (32) contacts the first trench electrode (30) from the first side (15.1) of the semiconductor body (15) for sensing a voltage from the first trench electrode (30), wherein the sensing electrode contact (32) is disposed at a second lateral position (42) spaced apart from the first lateral position (41).

2. A semiconductor die (1) as claimed in claim 1, wherein the control electrode contact (31) is arranged in a first half (35.1) of the lateral extension (35) of the first trench electrode (30), and the sensing electrode contact (32) is arranged in a second half (35.2) of the lateral extension (35), the control electrode contact (31) being particularly arranged at a first lateral end (30.1) of the first trench electrode (30), and the sensing electrode contact (32) being particularly arranged at a laterally opposite second end (30.2) of the first trench electrode (30).

3. The semiconductor die (1) as claimed in claim 1 or 2, wherein an electrode contact not contacting the first trench electrode (30) is arranged laterally between the control electrode contact (31) and the sense electrode contact (32).

4. A semiconductor die (1) as claimed in any one of the preceding claims, wherein the first trench electrode (30) is a gate electrode (26), which is arranged laterally next to the body region (13) of the transistor device (10) to create a channel in the body region (13).

5. The semiconductor die (1) of any one of claims 1 to 3, wherein the first trench electrode (30) is a field electrode (27) which is arranged laterally next to a drift region (14) of the transistor device (10) to shape the field in the drift region (14).

6. The semiconductor die (1) of claim 5, the transistor arrangement (10) further comprising: a gate electrode (26) disposed laterally adjacent to a body region (13) of the transistor device (10) and capacitively coupled to the body region (13), The gate electrode (26) has an elongated lateral extension and is disposed above the field electrode (27) in the trench (25).

7. A semiconductor die (1) as claimed in any one of the preceding claims, further comprising: A controllable clamping device (50) having a control terminal (51); The control terminal (51) of the controllable clamping device (50) is connected to the first trench electrode (30) via the sensing electrode contact (32), and the clamping device (50) is particularly connected in parallel with the transistor device (10).

8. The semiconductor die (1) of claim 7, wherein the controllable clamping device (50) is one of: A clamping field effect transistor (60), a MOS gate controlled diode and a field electrode controlled diode (65).

9. The semiconductor die (1) as claimed in claim 7 or 8, further comprising: A metal pad (70) disposed on the first side (15.1) of the semiconductor body (15); The control terminal (51) of the controllable clamping device (50) is connected to the sensing electrode contact (32) of the first trench electrode (30) via the metal pad (70).

10. The semiconductor die (1) of any one of claims 7 to 9, wherein the control terminal (51) of the controllable clamping device (50) is connected via a resistor R sense A resistor (85) is connected to the source region (11) of the transistor device (10), wherein the resistor R sense defined by the resistance of the first trench electrode (30) between the control electrode contact (31) and the sensing electrode contact (32), and / or The control terminal (51) of the controllable clamping device (50) is connected via a capacitor C sense A capacitor (130) is capacitively coupled to the drain region (12) of the transistor device (10), wherein the capacitor C sense The capacitance is defined by the capacitance between the first trench electrode (30) and the drain region (12).

11. The semiconductor die (1) as claimed in any one of claims 7 to 10, further comprising: an additional transistor device (100), without a sensing contactor, connected in parallel to the transistor device (10); The transistor device (10), the additional transistor device (100) and the controllable clamping device (50) are arranged in separate trenches.

12. The semiconductor die (1) as claimed in any one of the preceding claims, further comprising: an additional transistor device (100), without a sensing contactor, connected in parallel to the transistor device (10); The additional transistor device (100) has a grid-shaped gate structure having gate electrodes (26.1) extending in a first lateral direction (301) and gate electrodes (26.2) extending in a second lateral direction (302), wherein the additional transistor device (100) and the transistor device (10) are arranged next to each other in the second lateral direction (302), and at least some of the gate electrodes (26.2) extending in the second lateral direction (302) are interrupted between the additional transistor device (100) and the transistor device (10).

13. A package (101) having a semiconductor die (1) as claimed in any one of the preceding claims, The package (101) has a sensing pin (132); The sensing pin (132) is electrically connected to the sensing electrode contact (32) of the semiconductor die (1).

14. A method of using a semiconductor die (1) as claimed in any one of the preceding claims, the method comprising the steps of: - applying (180) an electric potential to the first trench electrode (30) via the control electrode contact (31); - sensing (181) an electric potential from the first trench electrode (30) via the sensing electrode contact (32), In particular, the following steps are additionally included: - applying (182) the electric potential sensed by the sensing electrode contactor (32) to a control terminal (51) of a controllable clamping device (50).

15. A method of manufacturing a semiconductor die (1) as claimed in any one of claims 1 to 12 or a package (101) as claimed in claim 13, the method comprising the following steps: - forming (185) the transistor device (10); - forming (186) the sensing electrode contact (32).

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