Method for manufacturing semiconductor packages using multiple air outlets or channels arranged over power lines

Abstract

A method of manufacturing a semiconductor package includes: providing a lead frame including a die pad and a first power line including a first side and an opposing second side; arranging at least one power semiconductor die on the die pad, electrically connecting the power semiconductor die with the first power line; arranging the lead frame in the cavity of the mold such that the first power line extends therefrom on a first lateral wall of the cavity; an air outlet / plurality of air outlets are provided in a first transverse wall / side wall of the cavity directly above a first side of the first power line such that the first side of the first power line forms a side wall of the air outlet / plurality of air outlets, and / or a plurality of channels are provided in the first side of the first power line, the plurality of channels are configured to act as air outlets for the cavity and to fill the cavity with a liquid molding material to form a molded body encapsulating the power semiconductor die, the plurality of air outlets enabling gas exhausted from the cavity by the liquid molding material to exit the cavity.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a method for manufacturing a semiconductor package , wherein the method comprises using an air outlet or channel arranged above a power line to enable gas in a cavity of a mold to be expelled from the cavity. BACKGROUND

[0002] The manufacturing of a semiconductor package can comprise molding over a semiconductor chip and a leadframe to manufacture a mold body. The mold body can be configured to protect the semiconductor chip from environmental hazards. To manufacture the mold body, a liquid molding material can be filled into a cavity of a mold, wherein the semiconductor chip and the leadframe are arranged in the cavity. The cavity of the mold can comprise an inlet for the liquid molding material and an outlet for excess liquid molding material. It is desirable that the liquid molding material completely fills the cavity such that no air bubbles remain in the cavity. When the molding material solidifies, the remaining air bubbles can cause gaps in the mold body. Such gaps in the mold body can damage the mechanical and / or electrical properties of the semiconductor package. It is known from KR101999027160A, JP2006229243A or JPH09181243A to provide an additional air outlet at the edge of the mold body in addition to the molding material outlet to avoid entrainment of air and to prevent gaps in the mold body. An improved method for manufacturing a semiconductor package can help to reduce or even eliminate the formation of such gaps and can also provide further advantages. SUMMARY

[0003] Different aspects relate to a method for manufacturing a semiconductor package, wherein the method comprises: providing a leadframe comprising a die-pad and a first power line, wherein the first power line comprises a first side and an opposite second side; arranging at least one power semiconductor die on the die-pad and electrically connecting the power semiconductor die with the first power line; arranging the leadframe in a cavity of a mold such that the first power line extends out of the cavity on a first lateral wall of the cavity; providing an air outlet in the first lateral wall of the cavity directly above the first side of the first power line such that the first side of the first power line forms a side wall of the air outlet, providing a plurality of air outlets in the first lateral wall of the cavity directly above the first side of the first power line such that the first side of the first power line forms a side wall of the plurality of air outlets, and / or wherein the method comprises providing a plurality of channels in the first side of the first power line, wherein the plurality of channels are configured to be used as air outlets for the cavity, and filling the cavity with a liquid molding material to form a mold body encapsulating the power semiconductor die, wherein the plurality of air outlets enable gas expelled from the cavity by the liquid molding material to exit the cavity.

[0004] Those skilled in the art will recognize, upon reading the following detailed description and viewing the drawings, additional features and advantages of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0005] In the drawings, which are not necessarily to scale, show by way of illustration only a few of the many aspects of the present disclosure, the same reference numbers used throughout different drawings designates similar or identical elements. The elements in the drawings outline are not necessarily to scale, unless otherwise implied by context. Features illustrated in different examples can be combined, unless mutually exclusive, unless mutually exclusive.

[0006] Figures 1A-1G A semiconductor package is shown in different stages of manufacture according to an exemplary method for manufacturing a semiconductor package. The method uses a mold that includes an air outlet arranged directly above a power line of the semiconductor package.

[0007] Figures 2A-2D Another semiconductor package is shown in different stages of manufacture according to another exemplary method for manufacturing a semiconductor package. The method includes arranging a channel in a first side face of a power line of the semiconductor package, wherein the channel functions as an air outlet during molding.

[0008] Figure 3 A semiconductor package is shown arranged in a cavity of a mold, wherein the cavity includes an inlet and an outlet for a liquid molding material.

[0009] Figure 4 A flow chart of an exemplary method for manufacturing a semiconductor package is shown, wherein the method includes providing an air outlet or a channel configured to function as an air outlet during molding. DETAILED DESCRIPTION

[0010] In the following detailed description, known structures and elements are shown in schematic form to facilitate description of one or more aspects of the present disclosure. In this regard, directional terminology, such as "upper," "lower," "left," "right," "above," "below," and the like, is used with reference to the orientation of the described figures. Because components of the present disclosure can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration only. It is to be understood that other examples can be used and structural or logical changes can be made.

[0011] Furthermore, although one example can be disclosed with reference to only one of multiple implementations, an example can also encompass one or more other examples as long as the other example(s) are within the spirit or scope of the example, as determined by the claims. Such claims may

[0012] The examples of semiconductor packages and methods for manufacturing semiconductor packages described below can use various types of semiconductor chips or various types of semiconductor circuits integrated into semiconductor chips, including AC / DC converter circuits or DC / DC converter circuits, inverter circuits, power MOS transistors, power Schottky diodes, JFET (junction gate field effect transistors), power bipolar transistors, integrated power circuits, etc. The examples can also use semiconductor chips comprising MOS transistor structures or vertical transistor structures, such as IGBT structures (insulated gate bipolar transistors) or generally transistor structures in which at least one electrical contact pad is arranged on a first main side of the semiconductor chip and at least one further electrical contact pad is arranged on a second main side of the semiconductor chip opposite the first main side of the semiconductor chip.

[0013] The semiconductor chips can be made of a specific semiconductor material, such as Si, SiC, SiGe, GaAs, GaN, or of any other semiconductor material, and can also contain one or more of non-semiconductor inorganic and organic materials, such as insulators, plastics or metals.

[0014] An efficient method for manufacturing a semiconductor package and an efficient semiconductor package, for example, can reduce material consumption, ohmic losses, chemical waste, etc., and, thus, can enable energy and / or resource savings. As given in this specification, the improved method for manufacturing a semiconductor package and the improved semiconductor package can thus at least indirectly contribute to a green technology solution, i.e., provide a climate-friendly solution that weakens the use of energy and / or resources.

[0015] Figures 1A-1G A semiconductor package 100 in different stages of manufacturing is shown according to an exemplary method for manufacturing a semiconductor package. The semiconductor package 100 may, for example, be a power semiconductor package configured to work with strong currents of, for example, 1 A or more, or 10 A or more, or 50 A or more, or 100 A or more, or even 500 A or more. The semiconductor package 100 may, additionally or alternatively, be configured to work with voltages of, for example, 100 V or more, or 250 V or more, or 500 V or more, or 600 V or more, or 1.2 kV or more, or even 2 kV or more. The semiconductor package 100 may, for example, be a surface mount device (SMD), or according to another example, a through-hole device (THD).

[0016] As shown in Figure 1A A leadframe 110 is provided. The leadframe 110 can comprise or consist of any suitable metal or any suitable metal alloy. For example, the leadframe 110 can comprise or consist of Al or Cu. It is noted that the specific configuration of the leadframe 110 shown in the figures is merely one example and any other suitable configuration can be used.

[0017] The leadframe 110 comprises a die pad 112 and a first power line 114. Further, the first power line 114 comprises a first side 114_1 and an opposite second side 114_2 (see Figure 1C ). The die pad 112 can also comprise a first side 112_1 and an opposite second side 112_2, wherein the first and second sides 112_1, 112_2 of the die pad 112 and the first and second sides 112_1, 114_1 of the first power line 114 have the same respective orientation.

[0018] According to one example, the leadframe 110 can comprise one or more additional power lines and / or one or more additional die pads. For example, the leadframe 110 can comprise a second power line 116 and / or one or more control lines 118. The first power line 114 may, for example, be configured to be electrically connected with a first power terminal (e.g., a source terminal, a drain terminal, an emitter terminal, or a collector terminal) of the power semiconductor die, and the second power line 116 can be configured to be connected with a second power terminal of the power semiconductor die. In other words, the first power line 114 and the one or more optional additional power lines of the leadframe 110 can be configured to serve as power contacts of the semiconductor package 100, which direct a load current. The control lines 118 may, for example, be configured to be connected with gate terminals of the semiconductor chip, and / or the control lines 118 can be configured to transmit a sensing signal, e.g., for temperature sensing, voltage sensing, etc.

[0019] As shown in Figure 1B The at least one power semiconductor die 120 is arranged, for example, on the first side 112_1 of the die pad 112, e.g., by soldering or sintering or gluing the power semiconductor die 120 onto the die pad 112 using an electrically conductive adhesive. Further, the power semiconductor die 120 is electrically connected with the first power line 114. According to the example shown in Figure 1B The first power line 114 and the die pad 112 are monolithically configured, and thus, when the power semiconductor die 120 is connected with the die pad 112, the power semiconductor die 120 is connected with the first power line 114. According to another example, the first power line 114 and the die pad 112 are non-monolithically configured, similar to the die pad 112 and the second power line 116. In this case, connecting the power semiconductor die 120 with the first power line 114 can comprise using an electrical connector (e.g., a wire bond, a ribbon, or a clip) to connect the power semiconductor die 120 with the first power line 114. The power semiconductor die 120 can also be electrically connected with the second power line 116.

[0020] According to one example, the semiconductor package 100 includes more than one power semiconductor die 120, e.g., two, four, six, etc. power semiconductor dies 120. The more than one power semiconductor die 120 can all be the same type of die, or, the power semiconductor dies 120 can be different types of dies. The more than one power semiconductor die 120 can be electrically connected to form any suitable type of circuit within the semiconductor package 100, e.g., a half-bridge circuit, a full-bridge circuit, a converter circuit, an inverter circuit, etc. All of the individual semiconductor dies 120 can be disposed on a single die pad 112 of the leadframe 110, or, at least two of the semiconductor dies 120 can be disposed on a common die pad 112.

[0021] As shown in Figure 1C the leadframe 110 is disposed in a cavity 132 of a mold 130 such that the first power line 114 extends out of the cavity 132 on a first side wall 134 of the cavity 132. The cavity 132 is configured to be filled with a liquid molding material to manufacture a molding body of the semiconductor package 100, wherein the molding body encapsulates the power semiconductor dies 120. It is noted that, Figure 1C corresponds to a cross-sectional view along the line C-C' in Figure 1B .

[0022] The mold 130 may, for example, include an upper half 136 and a lower half 138, wherein the cavity 132 is provided by sandwiching the leadframe 110 between the upper and lower halves 136, 138 of the mold 130.

[0023] According to one example, the mold 130 can include an inlet (not shown in Figure 1C ) configured to fill the cavity 132 with the liquid molding material. According to one example, the mold 130 can include an outlet (again, not shown in Figure 1C ) configured to enable excess liquid molding material to exit the cavity 132. The inlet may, for example, be disposed on a second side wall of the cavity 132, wherein the second side wall is opposite the first side wall 134. The outlet may, for example, be disposed opposite the inlet, e.g., on the first side wall 134.

[0024] The mold 130 includes an air outlet 140 in the first side wall of the cavity 132. The air outlet 140 is positioned directly above the first side 114_1 of the first power line 114, such that the first side 114_1 of the first power line 114 forms a side wall of the air outlet 140 (in particular, the first side 114_1 can form a lower side wall of the air outlet 140). The air outlet 140 extends from the cavity 132 to an outer side of the mold 130. The air outlet 140 is configured to enable gas in the cavity 132 to exit the mold 130.

[0025] Figure 1D A side view of the mold 130 is shown along the arrow D in Figure 1C Particularly, Figure 1D The air outlet 140 is shown in more detail according to one specific example. As shown, the air outlet 140 is arranged directly above the first side 114_1 of the first power line 114. According to one example, the mold 130 can comprise a further air outlet 142 arranged directly above the first side of the second power line 116 (such that the first side of the second power line 116 forms a side wall of the further air outlet 142). According to one example, the mold 130 comprises an air outlet directly above each power line, which air outlet is arranged along the first side wall 134 of the cavity 132.

[0026] As Figure 1D As shown in

[0027] For example, the air outlet 140 (and possibly the air outlet 142) can have a width in the range of about 0.5 mm to about 5 mm, wherein the width is measured parallel to the first side 114_1 of the first power line 114. The lower limit of the range can also be about 0.8 mm or about 1 mm, and the upper limit can also be about 4 mm or about 3 mm or about 2 mm or about 1.5 mm. For example, the air outlet 140 (and possibly the air outlet 142) can have a height of about 10 pm to about 100 pm, wherein the height is measured perpendicular to the first side 114_1 of the first power line 114. The lower limit of the range can also be about 20 pm or about 35 pm, and the upper limit can also be about 80 pm or about 50 pm.

[0028] In Figure 1DIn the example shown, mold 130 includes a single air outlet 140 disposed directly above the first power line 114, and a single additional air outlet 142 disposed directly above the second power line 116. According to another example, mold 130 includes at least two air outlets 140, for example, three air outlets 140, disposed side-by-side directly above the first side 114_1 of the first power line 114. Mold 130 may also include at least two additional air outlets 142, for example, three additional air outlets 142, disposed side-by-side directly above the first side of the second power line 116.

[0029] like Figure 1E As shown, cavity 132 is filled with liquid molding material 150 to create a molded body for packaging power semiconductor die 120. Air outlet 140 (or air outlets 140, 142) allows gas discharged from liquid molding material 150 to exit cavity 132. It should be noted that the gas discharged from cavity 132 through air outlet 140... Figure 1E The arrow in the diagram indicates the type of gas. The gas filling the cavity can be, for example, air, nitrogen, or any other suitable process gas.

[0030] According to one example, the at least one power semiconductor die 120 is electrically connected to a first power line 114 and / or a second power line 116 using one or more bonding wires or one or more tapes or a contact clip. During cavity filling 132, the liquid molding material may flow past the one or more bonding wires or tapes or contact clips and past the at least one power semiconductor die 120 before reaching the air outlet 140. Figures 1A-1G In the example shown, both the air outlet 140 and the semiconductor die 120 are positioned above the same side of the lead frame 110 (i.e., above the first sides 112_1, 114_1 of the die pads 112 and the power lines 114). This is likely because, without the air outlet 140, air bubbles could accumulate in the cavity 132 above this side of the lead frame 110.

[0031] Enabling gas in the cavity 132 to exit the cavity 132 when the liquid molding material 150 is filled into the cavity 132 can, for example, prevent voids from being formed in the molded body. Inspection of semiconductor packages manufactured without using the air outlet disclosed herein and computer simulations confirm that voids can primarily be formed directly above the first side of the power lines 114, 116. This can be especially the case if the inlet of the mold 130 is arranged on a side wall of the cavity 132 that is opposite to the power lines 114, 116. Furthermore, it has been found that air outlets or other types of outlets of the cavity 132 that are not arranged directly above the first side of the power lines 114, 116 (e.g., are arranged laterally next to the power lines 114, 116) can not prevent the formation of voids. In other words, gas can still be trapped in the cavity 132 even if an outlet is provided that is arranged laterally next to the power lines 114, 116. The gas can primarily be trapped directly above the first side of the power lines 114, 116 and, thus, it can be necessary to arrange one air outlet directly above the first side in order to remove the gas from the cavity 132 (in other words, the first side of the power lines 114, 116 can have to be a side wall of the air outlet in order for the air outlet to function as intended).

[0032] As shown in Figure 1F The liquid molding material 150 is cured to form the molded body 160 and the semiconductor package 100 is removed from the mold 130. In the example shown in Figure 1F The molded body 160 includes a molding flash 162 at the location of the air outlet 140 because the liquid molding material 150 at least partially filled the air outlet 140. According to another example, the air outlet 140 is so small and / or the liquid molding material 150 is so viscous that no liquid molding material 150 flows into the air outlet 140 and no molding flash 162 is formed.

[0033] In case a molding flash 162 is formed, the methods disclosed herein can optionally include a process of removing the molding flash 162 from the molded body 160. The removal process can, for example, include a chemical deburring process and / or a physical deburring process. The chemical deburring process can, for example, include the use of a suitable solvent to remove the flash 162 and the physical removal process can, for example, include the use of a gas stream or a water stream to remove the molding flash 162. The removal process can, for example, be performed before the molded body 160 is fully cured or, according to another example, after the molded body 160 is fully cured.

[0034] Figure 1GThe semiconductor package 100 after removal of the molding flash 162 (in case of forming molding flash) is shown. Due to the air outlet 140 (and optionally, the further air outlet 142), the molding body 160 can be substantially void-free or at least void-free on a large scale.

[0035] Figures 2A-2D Another semiconductor package 200 in different stages of manufacture according to another method for manufacturing a semiconductor package is shown. The semiconductor package 200 can be similar or identical to the semiconductor package 100 except for the differences described in the following. Furthermore, the disclosed method can be similar or identical to the method described with reference to Figures 2A-2D Figures 1A-1G

[0036] As shown in Figure 2A , a leadframe 210 is provided, which can be similar or identical to the leadframe 110. However, the leadframe 210 comprises a channel 212 in the first side face 114_1 of the first power line 114. The channel 212 is configured to serve as an air outlet similar to the air outlet 140 described above when the leadframe 210 is placed into the cavity of a mold. According to one example, the leadframe 210 comprises one or more additional power lines (e.g. the second power line 116), which are arranged laterally next to the first power line 114, and which can also comprise a channel (in the example shown in Figure 2A , the second power line 116 comprises a further channel 214). The one or more further channels can be similar or identical to the channel 212.

[0037] Figure 2B A cross-sectional view of the leadframe 210 along the line B-B' in Figure 2A is shown. As shown in Figure 2B , the channels 212, 214 can have a substantially rectangular cross-section, for example. According to another example, the channels 212, 214 have a square cross-section or a semi-circular cross-section or any other suitable cross-section.

[0038] The cross-section of the channels 212, 214 can have any suitable width and any suitable height. For example, the width and height of the channels 212, 214 can be identical to the width and height of the air outlets 140, 142 (see above). In particular, the dimensions of the channels 212, 214 can be small compared to the dimensions of the power lines 114, 116. At least for this reason, the channels 212, 214 do not impair the electrical and / or mechanical functionality of the power lines 114, 116.

[0039] ​​The channels 212, 214 can be manufactured using any suitable process. For example, the leadframe 210 can be subjected to a stamping process and / or an etching process and / or a laser ablation process to manufacture the channels 212, 214. For example, the manufacturing of the channels 212, 214 can be performed during the same stamping process as the manufacturing of the die pads 112 and the power lines 114, 116.

[0040] The first power line 114 can comprise lateral sides 114_3 connecting the first side 114_1 and the second side 114_2. According to one example, the width of the first power line 114 is in the range of 5 mm to 20 mm, wherein the width is measured between the opposing lateral sides 114_3. The lower limit of the range can also be about 6 mm or about 8 mm or about 10 mm, and the upper limit can also be about 18 mm or about 16 mm or about 14 mm or about 12 mm.

[0041] According to one example, the channels 212 are arranged centrally between the opposing lateral sides 114_3. According to one example, the first side 114_1 can comprise a plurality of channels 212. The channels 212 of the plurality of channels 212 can be arranged laterally side-by-side and centrally between the lateral sides 114_3 of the first power line 114, for example. In the same way, it is of course also possible that the second power line 116 comprises a plurality of further channels 214.

[0042] According to Figure 1D and Figure 2B the example shown in Figs. 1 1 and 12, the air outlets 140, 142 or the channels 212, 214 are arranged above or in the first side of the power lines 114, 116, and no air outlet or channel is arranged above or in the second, opposite side of the power lines 114, 116. According to another example, the air outlets 140, 142 and / or the channels 212, 214 are arranged not only above or in the first side of at least one of the power lines 114, 116, but also above or in the second side of at least one of the power lines.

[0043] Figure 2C A top view of the leadframe 210 arranged in the cavity of the mold 220 is shown. It is noted that the mold 220 in Figs. 13 and 14 is transparent to show the interior of the cavity 132. Furthermore, it is noted that the power semiconductor die 120 is arranged above the leadframe 210 before the leadframe 210 is inserted into the mold 220 (see Fig. 12). Figure 2C Figure 1B ).

[0044] ​The channels 212, 214 extend between the cavity of the mold 220 and the outside of the mold, and thus can function as air outlets that enable gas in the cavity to exit the cavity when the liquid molding material is filled into the cavity. Since the power lines 114, 116 of the leadframe 210 include the channels 212, 214, the sidewalls of the cavity of the mold 220 do not have to include the air outlets 140, 142 as the first sidewalls 134 of the mold 130.

[0045] Figure 2D The semiconductor package 200 is shown after the molding body 160 is formed by molding over the leadframe 210 and the power semiconductor die 120, as disclosed above with reference to the semiconductor package 100. As shown in Figure 2D As shown in the middle, during the manufacturing of the molding body 160, molding flashes 162 can be formed in the channels 212, 214. The molding flashes 162 can be removed, as described with reference to the semiconductor package 100.

[0046] The molding body 160 can include four lateral sides 164, wherein the first power line 114 and possibly also the second power line 116 are arranged on a first one of the lateral sides 164. According to one example, some or all of the lateral sides 164 have an edge length of about 1 cm or more, or about 1.4 cm or more, or about 2.1 cm or more, or about 4 cm or more, or about 5.5 cm or more, or about 7 cm or more. If the molding body 160 is viewed from above the first side 161 of the molding body, the molding body 160 can have a substantially square or substantially rectangular shape, for example (see Figure 2D ). Furthermore, the molding body 160 can have any suitable thickness, wherein the thickness is measured between the first side 161 and the opposite second side. The thickness can be in the range of about 1 mm to about 3 mm, for example. The lower limit of the range can also be about 2 mm or about 3 mm or about 5 mm, and the upper limit can also be about 2 cm or about 1.5 cm or about 1 cm or about 8 mm. According to one example, the thickness of the molding body 160 is not more than one fifth of the smallest edge length of the lateral sides 164 of the molding body 160.

[0047] Figure 3 A top view of a leadframe 300 arranged in a cavity of a mold 310 is shown. The leadframe 300 can be similar or identical to the leadframe 110 or the leadframe 210, and the mold 310 can be similar or identical to the mold 160 or to the mold 220. In particular, the leadframe 300 can include the channels 212, 214 and / or the mold 310 can include the air outlets 140, 142. For example, the leadframe 300 and the mold 310 can be used to manufacture the semiconductor package 100 or 200.

[0048] As shown in Figure 3 The mold 310 comprises an inlet 320 and an outlet 330. The inlet 320 can be used to fill the cavity of the mold 310 with liquid molding material, and the outlet 330 can be configured to enable excess liquid molding material to leave the cavity. As shown in Figure 3 The inlet 320 and the outlet 330 can be arranged, for example, on opposite lateral sides of the cavity of the mold 310. The outlet 330 can be arranged, for example, on the same lateral side as the air outlets 140, 142 or the channels 212, 214. Furthermore, the outlet 330 can be arranged laterally next to the power lines 114, 116 (and vice versa, the inlet 320 can be arranged laterally next to the control line 118). In other words, neither the inlet 320 nor the outlet 330 is arranged above one of the lines 114, 114, 118.

[0049] The cross section of the inlet 320 and the cross section of the outlet 330 can be larger, in particular significantly larger, than the cross section of the air outlets 140, 142 or the channels 212, 214. For at least this reason, it can not be possible or can be impractical to arrange the inlet 320 and the outlet 330 above one of the lines 114, 116, 118 (there can not be enough space above the lines 114, 116, 118).

[0050] Figure 4 is a flow chart of an exemplary method 400 for manufacturing a semiconductor package. The method 400 can be used, for example, to manufacture the semiconductor package 100 or 200.

[0051] The method 400 comprises a process of providing a leadframe comprising a die pad and a first power line, wherein the first power line comprises a first side and an opposite second side, at 401; a process of arranging at least one power semiconductor die on the die pad and electrically connecting the power semiconductor die with the first power line, at 402; a process of arranging the leadframe in a cavity of a mold such that the first power line extends out of the cavity on a first lateral wall of the cavity, at 403; a process of providing an air outlet in the first lateral wall of the cavity directly above the first side of the first power line such that the first side of the first power line forms a side wall of the air outlet, and / or providing a channel in the first side of the first power line, wherein the channel is configured to be used as an air outlet for the cavity, at 404; and a process of filling the cavity with liquid molding material to form a molding body encapsulating the power semiconductor die, wherein the air outlet enables gas expelled from the cavity by the liquid molding material to leave the cavity, at 405. Example

[0052] In the following, the method for manufacturing a semiconductor package is further explained using concrete examples.

[0053] Example 1 is a method for manufacturing a semiconductor package, wherein the method comprises: providing a leadframe comprising a die pad and a first power line, wherein the first power line comprises a first side and an opposite second side; arranging at least one power semiconductor die on the die pad and electrically connecting the power semiconductor die with the first power line; arranging the leadframe in a cavity of a mold such that the first power line extends out of the cavity on a first lateral wall of the cavity; providing an air outlet in the first lateral wall of the cavity directly above the first side of the first power line such that the first side of the first power line forms a side wall of the air outlet; and / or providing a channel in the first side of the first power line, wherein the channel is configured to serve as an air outlet for the cavity; and filling the cavity with a liquid molding material to form a molding body encapsulating the power semiconductor die, wherein the air outlet enables a gas being expelled from the cavity by the liquid molding material to exit the cavity.

[0054] Example 2 is the method of example 1, wherein the cavity comprises an inlet for the liquid molding material in a second lateral wall of the cavity, wherein the second lateral wall is opposite to the first lateral wall.

[0055] Example 3 is the method of example 1 or 2, wherein the leadframe comprises a second power line arranged in parallel to the first power line, wherein the method further comprises providing a further air outlet in the first lateral wall of the cavity directly above a first side of the second power line such that the first side of the second power line forms a side wall of the further air outlet, and / or comprising providing a further channel in the first side of the second power line, wherein the further channel is configured to serve as a further air outlet for the cavity.

[0056] Example 4 is the method of any of the preceding examples, wherein the method comprises providing a plurality of air outlets in the first lateral wall of the cavity directly above the first side of the first power line such that the first side of the first power line forms a side wall of the plurality of air outlets, and / or wherein the method comprises providing a plurality of channels in the first side of the first power line, wherein the plurality of channels is configured to serve as air outlets for the cavity.

[0057] Example 5 is the method of any of the preceding examples, wherein the air outlet has a height in the range of 10 pm to 50 pm, in particular in the range of 20 pm to 35 pm, wherein the height is measured perpendicular to the first side of the first power line.

[0058] Example 6 is the method of any of the preceding examples, wherein the air outlet has a width in the range of 0.5 mm to 5 mm, in particular in the range of 1 mm to 1.5 mm, wherein the width is measured parallel to the first side of the first power line.

[0059] Example 7 is the method of any of the preceding examples, wherein the first power line comprises lateral sides connecting the first side and the second side, wherein the first power line has a width in the range of 5 mm to 20 mm, wherein the width is measured between the opposing lateral sides.

[0060] Example 8 is the method of Example 7, wherein the air outlet or channel is arranged centrally between the opposing lateral sides.

[0061] Example 9 is the method of any of the preceding examples, further comprising: removing molding flash from the molded body at the location of the air outlet or channel.

[0062] Example 10 is the method of Example 9, wherein removing the molding flash comprises using a chemical de-flashing process.

[0063] Example 11 is the method of any of the preceding examples, further comprising: providing an outlet for the liquid molding material in the first side wall of the cavity laterally next to the first power line.

[0064] Example 12 is the method of any of the preceding examples, wherein the at least one power semiconductor die is electrically connected with the first power line using one or more bonding wires or ribbons, wherein, when filling the cavity, the liquid molding material flows past the one or more bonding wires or ribbons and past the at least one power semiconductor die before the liquid molding material reaches the air outlet or channel.

[0065] Example 13 is the method of any of the preceding examples, wherein the molded body comprises four lateral sides, wherein the first power line is arranged on a first one of the lateral sides, wherein the lateral sides have an edge length of 5.5 cm or more.

[0066] Example 14 is the method of any of Examples 1 to 12, wherein the molded body comprises four lateral sides, wherein the first power line is arranged on a first one of the lateral sides, wherein the lateral sides have an edge length in the range of 1.4 cm to 2.1 cm.

[0067] Example 15 is the method of any of Examples 13 or 14, wherein a thickness of the molded body is not more than one fifth of a minimum edge length of the lateral sides of the molded body.

[0068] Example 16 is an apparatus comprising means for performing the method according to any of the preceding examples.

[0069] It is noted that the methods and devices, including preferred embodiments thereof, can be used separately or in combination with other methods and devices disclosed in this document, as set forth in this document. Moreover, features set forth in connection with a device can also apply to a corresponding method, and vice versa. Furthermore, all aspects of the methods and devices set forth in this document can be combined in any combination. In particular, features of the examples can be combined with each other in any manner.

[0070] It is noted that the description and drawings are only illustrative of the principles of the proposed methods and systems. Those skilled in the art will be able to implement various arrangements which, although not explicitly described or shown in the text, embody the principles of the application and are included within its spirit and scope. Furthermore, all examples and embodiment set forth in this document are primarily intended to be illustrative only and are not to be taken as limiting in any way. Moreover, all statements relating to the principles, aspects and embodiments of the application as well as its specific examples provided in this document are intended to include their equivalents.

Claims

1. A method for manufacturing semiconductor packages (100, 200), the method comprising: A lead frame (110, 210) is provided, the lead frame including a die pad (112) and a first power line (114), wherein the first power line (114) includes a first side (114_1) and an opposing second side (114_2). At least one power semiconductor die (120) is disposed on the die pad (112), and the power semiconductor die (120) is electrically connected to the first power line (114). The lead frame (110, 210) is arranged in the cavity (132) of the mold (130) such that the first power line (114) extends out of the cavity (132) on the first sidewall (134) of the cavity (132). A plurality of air outlets (140) are provided in the first sidewall (134) of the cavity (132) directly above the first sidewall (114_1) of the first power line (114), such that the first sidewall (114_1) of the first power line (114) forms the sidewall of the plurality of air outlets (140), and / or, wherein the method includes providing a plurality of channels (212) in the first sidewall (114_1) of the first power line (114), wherein the plurality of channels (212) are configured to serve as air outlets for the cavity (132), and The cavity (132) is filled with liquid molding material (150) to form a molded body (160) encapsulating the power semiconductor die (120), wherein the plurality of air outlets allow gas discharged from the cavity by the liquid molding material (150) to leave the cavity (132).

2. The method according to claim 1, wherein, The cavity (132) includes an inlet (320) for the liquid molding material (150) in a second sidewall of the cavity (132), wherein the second sidewall is opposite to the first sidewall (134).

3. The method according to claim 1 or 2, wherein, The lead frame (110, 210) includes a second power line (116) arranged in parallel with the first power line (114). The method further includes providing an additional air outlet (142) in the first sidewall (134) of the cavity directly above the first side of the second power line (116), such that the first side of the second power line (116) forms the sidewall of the additional air outlet (142), and / or includes providing an additional channel (214) in the first side of the second power line (116), wherein the additional channel (214) is configured to serve as an additional air outlet for the cavity (132).

4. The method according to any one of the preceding claims, wherein, One of the plurality of air outlets has a height in the range of 10 μm to 50 μm, particularly in the range of 20 μm to 35 μm, wherein the height is measured perpendicular to the first side (114_1) of the first power line (114).

5. The method according to any one of the preceding claims, wherein, One of the plurality of air outlets has a width in the range of 0.5 mm to 5 mm, particularly in the range of 1 mm to 1.5 mm, wherein the width is measured parallel to the first side (114_1) of the first power line (114).

6. The method according to any one of the preceding claims, wherein, The first power line (114) includes a lateral side (114_3) connecting the first side and the second side (114_1, 114_2), wherein the width of the first power line (114) is in the range of 5 mm to 20 mm, wherein the width is measured between the opposing lateral sides (114_3).

7. The method according to any one of the preceding claims, further comprising: Deburrs (162) are removed from the molded body (160) at the locations of the plurality of air outlets (140) or the plurality of channels (212).

8. The method according to claim 7, wherein, Removing the molding burrs (162) includes using a chemical deburring process.

9. The method according to any one of the preceding claims, further comprising: An outlet (330) for the liquid molding material is provided laterally in the first sidewall (134) of the cavity (132) next to the first power line (114).

10. The method according to any one of the preceding claims, wherein, The at least one power semiconductor die (120) is electrically connected to the first power line (114) using one or more bonding wires or strips, wherein, when filling the cavity (132), the liquid molding material (150) flows past the one or more bonding wires or strips and past the at least one power semiconductor die (120) before the liquid molding material reaches the plurality of air outlets (140) or the plurality of channels (212).

11. The method according to any one of the preceding claims, wherein, The molded body (160) includes four transverse sides (164), wherein the first power line (114) is arranged on the first transverse side of the transverse sides (164), wherein the transverse side (164) has a side length of 5.5 cm or greater.

12. The method according to any one of claims 1 to 10, wherein, The molded body (160) includes four transverse sides (164), wherein the first power line (114) is arranged on the first transverse side of the transverse sides (164), wherein the transverse side (164) has a side length in the range of 1.4 cm to 2.1 cm.

13. The method according to any one of claims 11 or 12, wherein, The thickness of the molded body (160) is not greater than one-fifth of the minimum side length of the transverse side (164) of the molded body (160).

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