Patent Publication Number: US-2019189509-A1

Title: Contact Hole

Description:
TECHNICAL FIELD 
     The present disclosure relates to exemplary embodiments of a power semiconductor component and exemplary embodiments of a method for producing a power semiconductor component. In particular, the present disclosure relates to exemplary embodiments of a power semiconductor component with a contact hole and exemplary embodiments of a corresponding method. 
     BACKGROUND 
     Many functions of modern appliances in automotive, consumer and industrial applications, such as converting electrical energy and driving an electric motor or an electric machine, for instance, are based on power semiconductor devices. 
     By way of example so-called insulated-gate bipolar transistors (IGBTs), metal-oxide semiconductor field-effect transistors (MOSFETs) and diodes, but to name a few, are used for various applications, inter alia for switches in power sources and power converters. 
     Power semiconductor components are used in various structures, according to the respective use and the requirements placed thereon. Here, various materials and various lithographic techniques are typically used for forming a respective structure. 
     Some applications consider it advantageous, or demand, one or more contact holes to be provided in an insulating layer within a power semiconductor component, said contact holes being used for electrical contacting of a contact region arranged below the surface of the insulating layer. Here, the interest in an embodiment that saves as much space as possible on the one hand and the requirement of high contacting and manufacturing quality on the other hand sometimes present mutually opposing conditions. 
     SUMMARY 
     Aspects of the present description relate to power semiconductor component technology. 
     According to one exemplary embodiment, a power semiconductor component comprises a power semiconductor partial structure comprising a semiconductor body and an insulating layer, which is arranged on an upper side of the semiconductor body, wherein at least one contact hole is arranged on an upper side of the insulating layer, said contact hole, proceeding from the upper side of the insulating layer, extending at least partly within the insulating layer and being provided for electrical contacting of a contact region below the upper side of the insulating layer. Further, the power semiconductor component comprises an adhesion promoter layer, which is arranged on an upper side of the power semiconductor partial structure and which at least partly covers the upper side of the insulating layer and a surface of the contact hole; a tungsten-comprising layer, which is arranged on the adhesion promoter layer and at least partly covers the adhesion promoter layer and which has a first thickness in the region of the contact hole, said thickness being dimensioned in such a way that the tungsten-comprising layer fills the contact hole, and which has a second thickness in the region of the upper side of the insulating layer, said second thickness being less than the first thickness, and a connection layer, which is arranged on the tungsten-comprising layer. 
     According to a further exemplary embodiment, a power semiconductor component comprises a power semiconductor partial structure comprising a semiconductor body and an insulating layer, which is arranged on an upper side of the semiconductor body, wherein at least one contact hole is arranged on an upper side of the insulating layer, said contact hole, proceeding from the upper side of the insulating layer, extending at least partly within the insulating layer and being provided for electrical contacting of a contact region below the upper side of the insulating layer. Further, the power semiconductor component comprises an adhesion promoter layer, which is arranged on an upper side of the power semiconductor partial structure and which at least partly covers the upper side of the insulating layer and a surface of the contact hole; a tungsten-comprising layer, which is arranged on the adhesion promoter layer and at least partly covers the adhesion promoter layer and which has a first thickness in the region of the contact hole and which has a second thickness in the region of the upper side of the insulating layer, said second thickness being less than the first thickness, wherein the first thickness corresponds to at least half of the diameter of the contact hole, and a connection layer, which is arranged on the tungsten-comprising layer. 
     According to a further exemplary embodiment, a method for producing a power semiconductor component includes providing a power semiconductor partial structure comprising a semiconductor body and an insulating layer, which is arranged on an upper side of the semiconductor body, wherein at least one contact hole is arranged on an upper side of the insulating layer, said contact hole, proceeding from the upper side of the insulating layer, extending at least partly within the insulating layer and being provided for electrical contacting of a contact region below the upper side of the insulating layer. The method further includes applying an adhesion promoter layer to an upper side of the power semiconductor partial structure in such a way that the adhesion promoter layer at least partly covers the upper side of the insulating layer and a surface of the contact hole; applying a tungsten-comprising layer to the adhesion promoter layer in such a way that the tungsten-comprising layer at least partly covers the adhesion promoter layer and has a first thickness which is dimensioned in such a way that the tungsten-comprising layer fills the contact hole; removing part of the tungsten-comprising layer in the region of the upper side of the insulating layer in such a way that, after the removal, the tungsten-comprising layer has a second thickness in the region of the upper side of the insulating layer, said second thickness being less than the first thickness, and applying a connection layer to the tungsten-comprising layer. 
     According to a further exemplary embodiment, a method for producing a power semiconductor component includes providing a power semiconductor partial structure comprising a semiconductor body and an insulating layer, which is arranged on an upper side of the semiconductor body, wherein at least one contact hole is arranged on an upper side of the insulating layer, said contact hole, proceeding from the upper side of the insulating layer, extending at least partly within the insulating layer and being provided for electrical contacting of a contact region below the upper side of the insulating layer. The method further includes applying an adhesion promoter layer to an upper side of the power semiconductor partial structure in such a way that the adhesion promoter layer at least partly covers the upper side of the insulating layer and a surface of the contact hole; applying a tungsten-comprising layer to the adhesion promoter layer in such a way that the tungsten-comprising layer at least partly covers the adhesion promoter layer and has a first thickness, wherein the first thickness corresponds to at least half of the diameter of the contact hole; removing part of the tungsten-comprising layer in the region of the upper side of the insulating layer in such a way that, after the removal, the tungsten-comprising layer has a second thickness in the region of the upper side of the insulating layer, said second thickness being less than the first thickness, and applying a connection layer to the tungsten-comprising layer. 
     Additional features and advantages will become clear from the following detailed description and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Elements in the drawings are not necessarily illustrated with uniform scale. What is important, instead, is the illustration of principles of the invention. Moreover, reference signs in the drawings may denote corresponding elements. In the figures: 
         FIG. 1A  shows a schematic and exemplary illustration of a power semiconductor component; 
         FIG. 1B  shows a schematic and exemplary illustration of a further power semiconductor component; 
         FIG. 2  shows a schematic and exemplary illustration of a power semiconductor component according to one or more exemplary embodiments; 
         FIGS. 3A-3E  show schematic and exemplary illustrations of different stages of manufacture during the production of a power semiconductor component according to one or more exemplary embodiments; 
         FIG. 4  shows a schematic and exemplary illustration of a power semiconductor component according to one or more further exemplary embodiments; and 
         FIG. 5  shows a flowchart of a method for producing a power semiconductor component according to one or more exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, reference is made to the drawings, which form part of the present disclosure and which show certain exemplary embodiments, according to which the invention can be implemented, for elucidation purposes. 
     In this context, expressions relating to direction, such as, for example, “upper side”, “lower side”, “underneath”, “front side”, “behind”, “back”, “directed forwards”, “rearward”, “below”, “above”, etc., may be used with reference to an alignment of the described drawings. Because parts of exemplary embodiments may be positioned in various alignments, the terminology relating to direction is used for elucidation purposes and is in no way limiting. It is understood that it is possible to use other exemplary embodiments and make structural or logical changes, without departing from the scope of the present invention. Therefore, the following detailed description should not be understood in a limiting sense and the scope of the present invention is defined by the attached claims. 
     Detailed reference is made below to various exemplary embodiments, of which one or more examples are elucidated in the drawings. Each example is presented for elucidation purposes and should not be understood to delimit the invention. By way of example, features presented or described as part of one exemplary embodiment can be used in—or in conjunction with—other exemplary embodiments in order to yield a further exemplary embodiment. The intention is that the present invention also contains such modifications and developments. The examples are described using specific language that should not be construed as limiting the scope of the claims. The drawings are not to scale and only serve elucidation purposes. For improved clarity, identical elements or production steps are indicated by identical reference signs in the various drawings, provided nothing else is stated. 
     The term “horizontal”, as used in the present description, is intended to describe an alignment that is substantially parallel to a horizontal surface of a semiconductor substrate or a semiconductor structure. By way of example, this may be the surface of a semiconductor wafer or semiconductor chip. By way of example, the (first) lateral direction X and the (second) lateral direction Y, as mentioned below, could be horizontal directions, wherein the first lateral direction X and the second lateral direction Y may be perpendicular to one another. 
     The term “vertical”, as used in the present description, is intended to describe an alignment that is arranged substantially perpendicular to the horizontal surface, i.e., parallel to the normal direction of the surface of the semiconductor wafer/semiconductor chip. By way of example, the direction of extent Z, as mentioned below, could be a direction of extent that is perpendicular to both the first lateral direction X and the second lateral direction Y. 
     In the context of the present description, the expressions “in electrical contact” and “electrically connected” are intended to describe that a low-resistance electrical connection or low-resistance current path is present between two regions, sections, zones, portions or parts of the presently described apparatus. Moreover, in the context of the present description, the expression “in contact” is intended to describe that a direct physical connection is present between two elements of the respective semiconductor device; by way of example, a transition between two elements that are in contact with one another cannot contain a further interposed element or the like. 
     Further, in the context of the present description and provided nothing else is specified, the expression “electrical insulation” is intended to be used in the context of its generally valid interpretation and, accordingly, it is intended to describe that two or more components are positioned separately from one another and that no ohmic connection connecting these components is present. Nevertheless, components that are electrically insulated from one another may be coupled to one another, for example mechanically coupled and/or capacitively coupled and/or inductively coupled. So as to provide an example, two electrodes of a capacitor can be electrically insulated from one another and, at the same time, be coupled to one another in mechanical and capacitive fashion, for example by means of an insulator, for example by means of a dielectric. 
     Special exemplary embodiments, which are described in the present description, relate to a power semiconductor component, e.g., a power semiconductor component that can be used within a power converter or a power source, without being limited thereto. In one exemplary embodiment, such a component can be embodied accordingly to carry a load current that should be supplied to a load and/or that is provided accordingly by means of a power source. By way of example, the power semiconductor component can comprise one or more active power semiconductor cells, such as, for instance, a monolithically integrated diode cell and/or a monolithically integrated transistor cell and/or a monolithically integrated IGBT cell and/or a monolithically integrated RC-IGBT cell and/or a monolithically integrated MOS gated diode cell, (MGD) cell, and/or a monolithically integrated MOSFET cell and/or developments thereof. A plurality of such diode cells and/or transistor cells may be integrated in the component. 
     The expression “power semiconductor component”, as used in the present description, is intended to denote a single component with great voltage blocking and/or current carrying suitability. Expressed differently: such a power semiconductor component is provided for high currents, typically in the Ampere range, e.g., up to 5 or 100 A, and/or voltages, typically above 15 V, particularly typically up to 40 V or more, e.g., up to at least 500 V or more than 500 V, e.g. at least 600 V. 
     By way of example, the power semiconductor component described below can be a component that is embodied to be used as a power component in a low-voltage, mid-voltage and/or high-voltage application. By way of example, the expression “power semiconductor component”, as used in the present description, is not directed to logic semiconductor components, which are used, for example, for storing data, for processing data and/or for other types of semiconductor-based data processing. 
       FIG. 1A  shows a schematic illustration of a section of a cross-sectional view of a power semiconductor component  100 . The power semiconductor component  100  comprises a semiconductor body  110  and an insulating layer  120  with an upper side  121 , said insulating layer being arranged above the semiconductor body  110 . Proceeding from the upper side  121  of the insulating layer  120 , a contact hole  130  extends within the insulating layer  120 . The contact hole  130  facilitates electrical contacting of a contact region  160  that is situated below the surface  121  of the insulating layer  120  from above the insulating layer  120 . By way of example, the semiconductor body  110  and the insulating layer  120  are parts of a power semiconductor partial structure of the power semiconductor component  100 . 
     Moreover, the power semiconductor component  100  comprises a plug  144  which at least substantially fills the contact hole  130 . In the shown example, the plug  144  is made of tungsten, which was applied to the power semiconductor partial structure  110 ,  120  by means of sputtering and which was subsequently removed again from regions of the upper side  121  away from the contact hole  130 , for example by etching or chemical-mechanical polishing. A contact layer  141  is arranged between the contact region  160  and the plug  144 . The plug  144  and the contact layer  141  serve for electrical contacting of the semiconductor body  110  in the contact region  160 . By way of example, the depth of the contact hole  130  is 1.5 μm. Moreover, the contact hole  130  has a wedge-shaped cross-sectional profile in the shown example. Here, a smallest diameter of the contact hole  130  is situated in the vicinity of the contact region  160  and is 700 nm, for example. 
     Moreover, the power semiconductor component  100  comprises a connection layer  150 . The connection layer  150  is provided as an electrode of the power semiconductor component  100  and it comprises aluminum and/or copper, for example. As a result of the described structure of the power semiconductor component  100 , electrical contacting of the contact region  160  below the upper side  121  of the insulating layer  120  is facilitated by way of the connection layer  150  and by means of the plug  144  and the contact layer  141 . 
     In the shown example, the power semiconductor component  100  is a transistor, e.g., a MOSFET with a compensation structure. For the purposes of embodying the compensation structure, the semiconductor body  110  has various columns  110   a,    110   b  with different doping, for example with p-doping in first columns  110   a  and n-doping in second columns  110   b.  Here, the columns  110   b  form drift regions of the power semiconductor component  100 , for example. Moreover, a plurality of planar control electrodes  122   a,    122   b  are arranged within the insulating layer  120 , said control electrodes being electrically insulated from the connection layer  150  and being able to be impinged by a control signal, e.g., a gate signal, by way of an independent electric contact (not illustrated). 
     A pn-isolation, which is embodied by an n-source region  110   c  that is isolated from the remaining part of the semiconductor body  110  by a p-body region  110   d  and which is typical for MOSFETs, is situated in the contact region  160 . Both the p-body region  110   d  and the n-source region  110   c  are in electrical contact with the plug  144 . The control electrodes  122   a,    122   b  are embodied to induce an inversion channel in the p-body region  110   d  (which is also known as a “channel region”) in order thereby to put the power semiconductor component  100  into a conductive state. 
     One of the first columns  110   a  adjoins the p-body region  110   d.  It is known that the n-column  110   b  and the p-body region  110   d  form a body diode of the power semiconductor component  100 . 
     In some examples, a plurality of contact holes  130  are arranged in accordance with a matrix arrangement or any other pattern, for example another periodic pattern, in the power semiconductor partial structure  110 ,  120 . Here, control electrodes  122   a,    122   b  are in each case arranged between adjacent contact holes  130  within the insulating layer  120 . Moreover, one or more contact holes  130  have a trench-shaped embodiment for the purposes of forming a trench electrode in several examples. The cross-sectional view shown in  FIG. 1A  in this case corresponds to a view of an XZ-plane of the power semiconductor component  100 , for example, whereas the contact hole  130  extends in trench-shaped fashion in the Y-direction of the power semiconductor component  100 . 
       FIG. 1B  shows a schematic illustration of a section of a cross-sectional view of a further power semiconductor component  100 ′. Similar to the power semiconductor component  100  from  FIG. 1A , the power semiconductor component  100 ′ comprises a semiconductor component  110 ′ and an insulating layer  120 ′ with an upper side  121 ′ arranged above the semiconductor body  110 ′. Moreover, proceeding from the upper side  121 ′ of the insulating layer  120 ′, a contact hole  130 ′ also extends within the insulating layer  120 ′ in the power semiconductor component  100 ′ for the purposes of electrically contacting a contact region  160 ′ situated below the upper side  121 ′ of the insulating layer  120 ′ from above the insulating layer  120 ′ by way of a connection layer  150 ′ serving as an electrode. By way of example, the semiconductor body  110 ′ and the insulating layer  120 ′ are parts of a power semiconductor partial structure of the power semiconductor component  100 ′. 
     Deviating from the example of  FIG. 1A , the power semiconductor component  100 ′ comprises an adhesion promoter layer  142  arranged on an upper side  121 ′ of the insulating layer  120 ′ and a tungsten-comprising layer  144 ′ arranged on the adhesion promoter layer  142 . The adhesion promoter layer  142  and the tungsten-comprising layer  144 ′ form a layer composite  140  that electrically contacts the semiconductor body  110 ′ in the contact region  160 ′. In the shown example, the layer composite  140  covers both the upper side  121 ′ of the insulating layer  120 ′ and a surface of the contact hole  130 ′. Moreover, both the adhesion promoter layer  142  and the tungsten-comprising layer  144 ′, and also the layer composite  140  overall, have an at least substantially homogeneous thickness, both in the region of the upper side  121 ′ of the insulating layer  120 ′ and in the region of the contact hole  130 ′. 
     By way of example, the adhesion promoter layer  142  comprises titanium and/or titanium nitride. Moreover, the tungsten-comprising layer  144 ′ consists at least largely of tungsten in the shown example. By way of example, the layer composite  140  has a thickness in the range of 200 nm-300 nm. 
     The adhesion promoter layer  142  promotes an adhesive connection between the power semiconductor partial structure  110 ′,  120 ′ and the tungsten-comprising layer  144 ′. The tungsten-comprising layer  144 ′ promotes electrical contacting of the contact region  160 ′. For instance, an exemplary depth of the contact hole  130 ′ is 1 μm-1.5 μm and the smallest diameter of the contact hole  130 ′ varies from approximately 500 nm in a lower region of the contact hole to approximately 700 nm in an upper region of the contact hole  130 ′, for example. In the case of such profiles, tungsten penetrates in a more conform fashion into the contact holes  130 ′ and also exhibits a more conform deposition behavior than aluminum or copper, for example, which are preferably usable for the connection layer  150 ′. Moreover, the layer composite  140  inhibits outward diffusion of possible doping from the power semiconductor partial structure  110 ′,  120 ′. Titanium present in the adhesion promoter layer  142 , in particular, is effective as a diffusion barrier. 
     By way of example, the application of the adhesion promoter layer  142 , the tungsten-comprising layer  144 ′ and the connection layer  150 ′ is implemented in successive steps, for instance by means of sputtering or chemical vapor deposition in each case. Moreover, in this context, the tungsten-comprising layer  144 ′ offers protection for the more sensitive adhesion promoter layer  142  against unwanted ablation of the adhesion promoter layer  142  by certain processing steps in the production process of the power semiconductor component  100 ′. 
     In contrast to the example of  FIG. 1A , the contact hole  130 ′ in the power semiconductor component  100 ′ is substantially filled with material of the connection layer  150 ′. While aluminum and/or copper are preferably used for the connection layer  150 ′, cavities, so-called voids, often form within the contact hole  130 ′ on account of the deposition behavior of these materials, as illustrated in  FIG. 1B  by the cavity L. Disadvantages may arise therefrom, for example if process gases or other chemical residues are included in the cavity L; this may subsequently adversely affect the functionality or service life of the power semiconductor component  100 ′. Moreover, a cavity L may collapse uncontrollably still during the further application of the connection layer  150 ′ and thus have an irregular application of the connection layer  150 ′ as a consequence. In some cases, a cavity L moreover leads to the formation of a so-called pinhole during the further application of the connection layer  150 ′, i.e., to a hollow channel extending through the connection layer  150 ′ proceeding from the cavity L. 
       FIG. 2  shows a schematic illustration of a cross-sectional view of a power semiconductor component  200  according to one exemplary embodiment. The power semiconductor component  200  likewise comprises a semiconductor body  210 , an insulating layer  220 , an adhesion promoter layer  242  arranged on an upper side  221  of the insulating layer  220 , a tungsten-comprising layer  244  arranged on the adhesion promoter layer  242  and a connection layer  250  arranged on the tungsten-comprising layer  244 . Further, the power semiconductor component  200  also has a contact hole  230 , which extends at least partly within the insulating layer  220  for the purposes of electrically contacting a contact region  260  below the upper side  221  of the insulating layer  220 . Provided nothing else emerges from the following explanations, what was stated in the context of the power semiconductor component  100 ′ of  FIG. 1  applies accordingly in respect of the power semiconductor element  200  and the aforementioned features. 
     In the shown example, the contact hole  230  extends up to the upper side of the semiconductor body  210 , while the contact region  260  is also situated on the upper side of the semiconductor body  210 . By contrast, in other examples, the contact hole  230  extends into the semiconductor body  210 , in a manner similar to the example of  FIG. 1A . Here, the contact region  260  is also situated within the semiconductor body  210 , for example. In further examples, the contact hole  230  extends within the insulating layer  220  without reaching the semiconductor body  210  and the contact region  260  is also situated above the semiconductor body  210 . Here, the contact hole  230  is provided, for example, for the purposes of contacting electrical components arranged within the insulating layer  220 , such as control electrodes, for example. 
     In contrast to the example of  FIG. 1 , the tungsten-comprising layer  244  in the power semiconductor component  200  does not have a uniform thickness in the region of the upper side  221  of the insulating layer  220  and in the region of the contact hole  230 . Instead, in the region of the contact hole  230 , the tungsten-comprising layer  244  has a first thickness D 1  in relation to a surface of the contact hole  260  on which the tungsten-comprising layer  244  is applied, said first thickness being dimensioned in such a way that the tungsten-comprising layer  244  at least substantially fills the contact hole  260 . 
     In the shown example, the thickness D 1  is dimensioned in such a way that the contact hole  260  is completely filled. By contrast, in other examples, the thickness D 1  is dimensioned in such a way that the tungsten-comprising layer  244  largely fills, but does not completely fill, the contact hole  260 . By way of example, the contact hole  260  does not have a perpendicular lateral or side face as illustrated schematically in  FIG. 2  in this case; instead it has an at least partly wedge-shaped cross-sectional profile, for example. In these cases, the thickness D 1  corresponds to at least half of the diameter of the contact hole  230 , as averaged over the depth of the contact hole  230 , for example. The diameter at a respective depth is determined, for example, in the tightest direction of extent of the contact hole  230  in each case, i.e., according to a smallest diameter at the respective depth. The diameter averaged over the depth of the contact hole  230  is moreover determined according to an arithmetic or geometric mean, for example. By way of example, in the case of the thickness D 1  of the tungsten-comprising layer determined thus, a conical contact hole  230  or a trench-shaped contact hole  230  with a wedge-shaped cross-sectional layer is also at least largely filled by the tungsten-comprising layer  244 . 
     At least largely filling the contact hole  230  by means of the tungsten-comprising layer  244 , as described above, promotes the formation of an electrical connection between the connection layer  250  and the contact region  260 . At the same time, this avoids possible difficulties that may arise if an interior of the contact hole  230  is intended to be filled by means of the connection layer  250 , as described in conjunction with  FIG. 1 . This promotes, in particular, the use of aluminum and/or copper as constituent parts of the connection layer  250 , which have a disadvantageous, less conformal deposition behavior for filling the contact hole  230 ′ than tungsten in the case of conventional deposition processes and preferred dimensions of the contact hole  230 , as described in conjunction with  FIGS. 1A and 1B . 
     By contrast, in the region of the upper side  221  of the insulating layer  220 , the tungsten-comprising layer  244  has a second thickness D 2 , which is less than the first thickness D 1 . A lower thickness D 2  of the tungsten-comprising layer  244  on the upper side  221  of the insulating layer  220  is suitable for avoiding excessive mechanical stresses in the power semiconductor component  200  as a result of the tungsten-comprising layer  244 . This is advantageous, particularly in the case of power semiconductor components  200  that have a comparatively large upper side  221 . At the same time, the thickness D 2  of the tungsten-comprising layer  244  is dimensioned in such a way in certain examples that the tungsten-comprising layer  244  offers sufficient protection to the adhesion promotion layer  242 , lying therebelow, in relation to subsequent production steps, for example in relation to subsequent etching processes. 
     In some examples, the first thickness D 1  lies in the range of 300 nm-600 nm, for example in the range of 400 nm-500 nm. Moreover, the second thickness D 2  lies in the range of 100 nm-300 nm in some examples, for example in the range of 150 nm-250 nm. By contrast, the adhesion promoter layer  242  is less than 100 nm in some examples. 
     Moreover, the insulating layer  220  comprises borophosphosilicate glass, BPSG, in some examples. In further examples, the insulating layer  220  comprises silicon nitride and/or undoped oxide, for example in combination with BPSG. 
       FIGS. 3A-3E  show schematic illustrations of various manufacturing stages during the production of a power semiconductor component  200  as described in conjunction with  FIG. 2 . 
       FIG. 3A  shows a power semiconductor partial structure comprising a semiconductor body  210  and an insulating layer  220  applied thereon (manufacturing stage  310 ). Here, a contact hole  230  for contacting the contact region  260  has already been formed in the insulating layer  220 . By way of example, conventional coating, masking and/or ablation techniques can be used for producing the power semiconductor partial structure  210 ,  220 . 
       FIG. 3B  shows the power semiconductor partial structure  210 ,  220  after applying the adhesion promoter layer  242  (manufacturing stage  320 ). The adhesion promoter layer  242  is formed by depositing, for example sputtering, titanium and/or titanium nitride. 
       FIG. 3C  shows a subsequent manufacturing stage  330  after the tungsten-comprising layer  244  with a thickness D 1 , as described above, has been applied to the adhesion promoter layer  242 . The tungsten-comprising layer  244  is likewise formed by depositing, for example sputtering, tungsten. The chosen thickness D 1  ensures that the contact hole  230  is at least substantially filled by the tungsten-comprising layer  244 . 
       FIG. 3D  shows the structure from  FIG. 3C , wherein the tungsten-comprising layer  244  has been partly removed again from outside of the contact hole  230  (manufacturing stage  340 ). The tungsten-comprising layer  244  has been ablated, for example by chemical-mechanical polishing, CMP, and/or etching back, to such an extent that it has a thickness D 2 , as described above, in the region of the upper side  221  of the insulating layer  220 . 
       FIG. 3E  shows the power semiconductor component  200  after applying the connection layer  250  to the tungsten-comprising layer  244  (manufacturing stage  350 ). The connection layer  250  has been formed by depositing, e.g., sputtering, aluminum and/or copper. 
       FIG. 4  shows a schematic illustration of a section of a cross-sectional view of a power semiconductor component  400  according to a further exemplary embodiment. The power semiconductor component  400  comprises a semiconductor body  410  and an insulating layer  420  arranged thereon as constituent parts of a power semiconductor partial structure. Moreover, an adhesion promoter layer  442  is also arranged on an upper side of the power semiconductor partial structure  410 ,  420  in the case of the power semiconductor component  400 , a tungsten-comprising layer  444  and a connection layer  450  in turn being arranged on said adhesion promoter layer. Moreover, the power semiconductor element  400  also comprises a contact hole  430  for electrically contacting a contact region  460  below the upper side  421  of the insulating layer  420 . The tungsten-comprising layer  444  has a first thickness D 1  in the region of the contact hole  430  and a second thickness D 2 , which is less than the first thickness D 1 , in the region of the upper side  421  of the insulating layer  420 . Provided nothing else emerges from the following explanations, what was stated in the context of  FIG. 2  applies accordingly in respect of the power semiconductor element  400  and the aforementioned features. In particular, the thickness D 1  is at least half a mean diameter DM of the contact hole  430 . This ensures that the tungsten-comprising layer  444  at least substantially fills the contact hole  430 . 
     Like in the example of  FIG. 1A , the power semiconductor component  400  can be a MOSFET, for example a MOSFET with a compensation structure. The power semiconductor component  400  likewise comprises a plurality of planar control electrodes  422   a,    422   b  in this case, said planar control electrodes being arranged within the insulating layer  420 . Here, the control electrodes  422   a,    422   b  are arranged on different sides of the contact hole  430  and serve, for example, to form an inversion channel in a body region (not illustrated in  FIG. 4 ) of the semiconductor body  410 . 
     In contrast to the example of  FIG. 2 , the contact hole  430  in the power semiconductor element  400  is embodied with an irregular, in particular partly angled, cross-sectional profile. Here, the first thickness D 1  is chosen in such a way that it corresponds to approximately half a mean diameter of the contact hole  430 . Here, a widening of the contact hole  430  in the upper region has as a consequence that the tungsten-comprising layer  444  largely fills the contact hole  430 , albeit not completely. However, according to what was said above, it is understood that, even in the case of the power semiconductor component  400 , possible difficulties, which may arise when filling the contact hole  430  substantially by means of the connection layer  450 , are effectively avoided. 
       FIG. 5  shows a flowchart of a method  500  for producing a power semiconductor component, for example the power semiconductor components  200 ,  400  as described in conjunction with  FIGS. 2 to 4 . In some examples, steps of the method  500  are suitable for producing manufacturing steps  310 - 350 , as described in conjunction with  FIGS. 3A to 3E . 
     The method  500  includes providing a power semiconductor partial structure (step  510 ). Here, this is a power semiconductor partial structure as described in conjunction with  FIGS. 2 to 4 , for example. 
     Further, the method  500  includes applying an adhesion promoter layer to an upper side of the power semiconductor partial structure (step  520 ). Here, the adhesion promoter layer is applied in such a way that it at least partly covers the upper side of an insulating layer of the power semiconductor partial structure. In some examples, the adhesion promoter layer comprises titanium and/or titanium nitride. Here, the adhesion promoter layer is applied by means of sputtering, for example. In further examples, the adhesion promoter layer is applied at least in part by means of chemical vapor deposition. 
     The method  500  further includes applying a tungsten-comprising layer on the adhesion promoter layer in such a way that the tungsten-comprising laser at least partly covers the adhesion promoter layer (step  530 ). Moreover, applying the tungsten-comprising layer is implemented in such a way that the tungsten-comprising layer has a first thickness D 1 , for example on the entire upper side of the semiconductor partial structure, said thickness being dimensioned in such a way that the tungsten-comprising layer fills the contact hole of the power semiconductor partial structure. As an alternative thereto, the tungsten-comprising layer largely fills the contact hole of the power semiconductor partial structure, albeit not completely, in further examples. By way of example, the first thickness D 1  corresponds to at least half of the diameter of the contact hole, for example a smallest diameter of the contact hole averaged over the depth of the contact hole. 
     In some examples, the tungsten-comprising layer consists at least substantially of tungsten. Moreover, the tungsten-comprising layer is applied by means of chemical vapor deposition in some examples. In further examples, the tungsten-comprising layer is applied at least in part by means of sputtering. 
     Further, the method  500  includes removing part of the tungsten-comprising layer in a region of the upper side of the insulating layer of the power semiconductor partial structure (step  540 ). By way of example, the removal is implemented by means of back etching and/or chemical-mechanical polishing, CMP. Moreover, removal is implemented in such a way that, after the removal, the tungsten-comprising layer has a second thickness D 2  in the region of the upper side of the insulating layer, said second thickness being less than the first thickness D 1 . 
     Removing the part of the tungsten-comprising layer, step  540 , in the region of the upper side of the insulating layer is implemented without a removal of part of the tungsten-comprising layer within the contact hole in some examples. 
     Further, the method  500  includes applying a connection layer to the tungsten-comprising layer (step  550 ). By way of example, the connection layer comprises copper and/or aluminum. In some examples, the connection layer is applied at least partly by means of deposition, for example by means of sputtering or chemical vapor deposition. 
     Spatially relative terms such as “under”, “below”, “lower, “on”, “above” and the like, are used for ease of description to explain the positioning of one element relative to a second element. These terms are intended to encompass different orientations of the respective device in addition to different orientations than those depicted in the figures. Moreover, terms such as “first”, “second”, and the like, are used to describe various elements, regions, sections, etc. and are also not intended to be limiting. Like terms refer to like elements throughout the description. 
     The terms “having”, “containing”, “including”, “comprising”, “exhibiting” and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. 
     With the above range of variations and applications in mind, it should be understood that the present invention is not limited by the foregoing description, nor is it limited by the accompanying drawings. Instead, the present invention is limited only by the following claims and their legal equivalents.