Semiconductor package with directional antenna

Abstract

In some examples, a semiconductor package (100) includes: a semiconductor die (98); a conductive component (102) coupled to the semiconductor die; and a multilayer package substrate. The multilayer package substrate comprises: a first horizontal metal layer (104) providing a ground connection; a second horizontal metal layer (105) over the first horizontal metal layer; a vertical member (108B, 108D, 110B, 110D, 112B, 112D) coupled to the first and second horizontal metal layers; and a molding compound covering the first and second horizontal metal layers and the vertical member. The first horizontal metal layer, the second horizontal metal layer, and the vertical member together form a structure including a conductive band (106) coupled to the conductive member, a transition member (108) coupled to the conductive band, a waveguide (110) coupled to the transition member, and a horn antenna (112) coupled to the waveguide.

Description

Background Art

[0001] Semiconductor chips are usually housed inside semiconductor packages, which protect the chips from harmful environmental influences such as heat, moisture, and debris. The packaged chip communicates with electronic devices outside the package via conductive terminals (such as leads) exposed to the package surface. Within the package, the chip can be electrically coupled to the conductive terminals using any suitable technology. One such technology is the "flip chip" technology, in which the semiconductor chip (also referred to as the "die") is oriented so that the device side of the chip (where the circuit system is formed) is downward. The device side is coupled to the conductive terminal using, for example, a solder bump. Another technology is a wire bonding technology, in which the device side of the semiconductor chip is oriented upward and is coupled to the conductive terminal using a bonding wire. The bonding wire is formed on a bonding pad, which is positioned on the semiconductor die and provides a joint between the bonding wire and the circuit system of the semiconductor die. Summary of the invention

[0002] In some examples, a semiconductor package includes: a semiconductor die; a conductive component coupled to the semiconductor die; and a multi-layer package substrate. The multi-layer package substrate includes: a first horizontal metal layer providing a ground connection; a second horizontal metal layer above the first horizontal metal layer; a vertical component coupled to the first and second horizontal metal layers; and a molding compound covering the first and second horizontal metal layers and the vertical component. The first horizontal metal layer, the second horizontal metal layer, and the vertical component together form a structure including a conductive strip coupled to the conductive component, a transition component coupled to the conductive strip, a waveguide coupled to the transition component, and a horn antenna coupled to the waveguide.

[0003] In some examples, a method for manufacturing a semiconductor package includes forming a multilayer package substrate by: plating a first horizontal metal ground layer on a carrier; plating a plurality of vertical components on the first horizontal metal ground layer; applying a first molding compound to the first horizontal metal ground layer and the plurality of vertical components; grinding at least a portion of the molding compound and the plurality of vertical components; plating a second horizontal metal layer on the plurality of vertical components; applying a second molding compound to the second horizontal metal layer; and grinding at least a portion of the second molding compound and the second horizontal metal layer. The method includes coupling a semiconductor die to the second horizontal metal layer, and applying a third molding compound to the second molding compound and the semiconductor die. The first horizontal metal ground layer, the plurality of vertical components, and the second horizontal metal layer form a structure including a conductive strip coupled to the semiconductor die and a plurality of impedance matching components of different shapes configured to guide electromagnetic waves in a predetermined direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Figure 1A are perspective views of molded semiconductor packages that include directional antennas and efficient signal paths therein in various examples.

[0005] Figure 1B is a front view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0006] Figure 1C are cutaway cross-sectional views of molded semiconductor packages that include directional antennas and efficient signal paths therein in various examples.

[0007] Figure 1D is a top view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0008] Figure 2A are perspective views of molded semiconductor packages that include directional antennas and efficient signal paths therein in various examples.

[0009] Figure 2B is a front view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0010] Figure 2C is a side view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0011] Figure 2D are top perspective views of molded semiconductor packages that include directional antennas and efficient signal paths therein in various examples.

[0012] Figure 2E are perspective views of molded semiconductor packages that include directional antennas and efficient signal paths therein in various examples.

[0013] Figure 2F is a side view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0014] Figure 3 is a graph depicting the efficiency of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples.

[0015] Figure 4 are perspective views of electric field diagrams depicting the efficiency of a molded semiconductor package having a directional antenna and an efficient signal path therein in various examples.

[0016] Figure 5 is a side view of an electric field diagram depicting the efficiency of a molded semiconductor package containing a directional antenna and an efficient signal path therein in various examples.

[0017] Figure 6 is a schematic diagram depicting the directivity of antennas in molded semiconductor packages in various examples.

[0018] Fig. 7A are perspective views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0019] Figure 7B is an elevation view of a molded semiconductor package that includes a directional antenna, an efficient signal path, and a grounded coplanar waveguide therein in various examples.

[0020] Figure 7C are cutaway cross-sectional views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0021] Fig.7D are top perspective views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0022] Fig. 8A are perspective views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0023] Figure 8B is an elevation view of a molded semiconductor package that includes a directional antenna, an efficient signal path, and a grounded coplanar waveguide therein in various examples.

[0024] Figure 8C are cutaway cross-sectional views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0025] Fig.8D are top perspective views of molded semiconductor packages that include directional antennas, efficient signal paths, and grounded coplanar waveguides therein in various examples.

[0026] Fig. 9 is a graph depicting the efficiency of a molded semiconductor package that includes a directional antenna, an efficient signal path, and a grounded coplanar waveguide therein in various examples.

[0027] Fig.10 are perspective views of electric field diagrams depicting the efficiency of a molded semiconductor package containing a directional antenna, an efficient signal path, and a grounded coplanar waveguide therein in various examples.

[0028] Fig.11 are perspective views of electric field diagrams depicting the efficiency of a molded semiconductor package containing a directional antenna, an efficient signal path, and a grounded coplanar waveguide therein in various examples.

[0029] Fig.12 is a schematic diagram depicting the directivity of antennas in molded semiconductor packages in various examples.

[0030] Fig.13A and 13B is a process flow diagram of a method for manufacturing a semiconductor package including a directional antenna and an efficient signal path therein in various examples.

[0031] Fig.14 is a flow chart of a method for fabricating a semiconductor package including a directional antenna and an efficient signal path therein in various examples. DETAILED DESCRIPTION

[0032] Some types of semiconductor packages include circuitry for wireless applications. For example, a semiconductor package used in a wireless application may include a semiconductor die having radio frequency (RF) circuitry formed on the device side of the die, and such circuitry may be coupled to an antenna included in the package. In some wireless applications, such as radar, 5G, and other high-frequency applications, it is difficult to achieve an efficient, low-loss signal path between the semiconductor die and the antenna. This challenge is exacerbated in the case of highly directional antennas integrated into the semiconductor package, and in a molded compound encapsulated package, the challenge is even greater.

[0033] The present specification describes various examples of molded semiconductor packages, such as quad flat no-lead (QFN) packages, that mitigate the challenges described above. Specifically, the molded semiconductor packages described herein include a directional antenna integrated with the package. The package includes an efficient, low-loss signal path between the packaged antenna and the semiconductor die. The signal path and the antenna are formed in a multi-layer package substrate, the multi-layer package substrate including: a first horizontal plated metal layer providing a ground connection; a second horizontal plated metal layer above the first plated metal layer; a plated vertical member coupled to the first and second horizontal plated metal layers; and a molding compound that abuts the first and second horizontal plated metal layers and the plated vertical member. The first horizontal plated metal layer forms a conductive strip that is coupled to a conductive member and is configured to direct electromagnetic waves away from the conductive member. The first and second horizontal plated metal layers and the plated vertical member form a transition member coupled to the conductive strip, the transition member having a flared shape and configured to direct electromagnetic waves away from the conductive strip. The first and second horizontal plated metal layers and the plated vertical member form a waveguide coupled to the transition member, the waveguide having a rectangular prism shape and configured to guide electromagnetic waves away from the transition member. The first and second horizontal plated metal layers and the plated vertical member form a horn antenna coupled to the waveguide and configured to guide electromagnetic waves from the waveguide to a predetermined direction.

[0034] By forming the metal structures in the package using electroplating techniques as described below, undesirable gaps that would otherwise occur between the individual components that make up such metal structures (e.g., vias that do not touch each other) will allow energy to escape, thereby significantly reducing efficiency. Efficiency is further improved by designing impedance-matched continuous metal structures in the package so that electromagnetic (EM) waves propagating across the boundaries of the structure are maximally transmitted across the boundaries and minimally reflected backward and away from the boundaries. In addition, as described in more detail below, the metal structures are oriented to produce high directivity, meaning that EM (e.g., RF) waves are emitted in a specific direction. The package is also well suited to accommodate high frequencies (e.g., 400 MHz to 52 GHz) because in these frequency ranges, antennas can be integrated into the package. This is because the antenna must have a size that approximates the wavelength of the EM wave in the molding compound environment (high dielectric constant). In this frequency range (e.g., 400 MHz to 52 GHz), the wavelength is smaller than the size of the package (less than 100 mm). 2 ), which allows the antenna to be integrated in the package. Therefore, the package can be used for high-frequency applications such as radar (400MHz to 36GHz) and 5G (450MHz to 52GHz).

[0035] Figure 1A 1 is a perspective view of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples. Semiconductor package 100 includes semiconductor die 98, conductive member 102, first horizontal metal layer 104, conductive strip 106, transition member 108, waveguide 110, and horn antenna 112. Semiconductor die 98 includes circuitry configured to perform any suitable function, such as processing signals to be transmitted via horn antenna 112 and / or processing signals received via horn antenna 112. Semiconductor die 98 is positioned above first horizontal metal layer 104 and is formed by molding compound (in Figures 2A-2D In the example, the device side of semiconductor die 98 having the circuitry formed therein faces downward toward first horizontal metal layer 104.

[0036] The first horizontal metal layer 104 includes a metal, such as copper, nickel, aluminum, or gold, and is coupled to a ground connection, such as on a printed circuit board (PCB) or other structure to which the semiconductor package 100 may be coupled. Thus, the first horizontal metal layer 104 serves as a ground plane. The first horizontal metal layer 104 forms a bottom surface of the transition component 108, the waveguide 110, and the horn antenna 112, and as shown, the first horizontal metal layer 104 also extends horizontally beyond the transition component 108, the waveguide 110, and the horn antenna 112. The second horizontal metal layer 105 forms a top surface of the conductive strip 106, the transition component 108, the waveguide 110, and the horn antenna 112. Unlike the first horizontal metal layer 104, the second horizontal metal layer 105 does not extend horizontally beyond the conductive strip 106, the transition component 108, the waveguide 110, and the horn antenna 112.

[0037] Conductive strap 106 is a transmission line configured to provide input and output signals to the circuitry of semiconductor die 98. Conductive strap 106 is defined as a conductor separated from first horizontal metal layer 104 (ground plane) by a dielectric, such as molding compound positioned between conductive strap 106 and first horizontal metal layer 104. In some examples, this dielectric can be a material other than molding compound, such as air. Conductive strap 106 is formed by second horizontal metal layer 105. Because conductive strap 106 is relatively Figure 1A The other components of semiconductor package 100 shown in FIG. 1 are relatively thin, so second horizontal metal layer 105 is sufficient to form the entire vertical thickness of conductive ribbon 106. Conductive ribbon 106 is coupled to the circuitry of semiconductor die 98 through conductive features 102 (eg, copper pillars).

[0038] A transition component 108 is coupled to the end of the conductive ribbon 106 that is away from the semiconductor die 98. The transition component is defined as a flared metal waveguide for confining and transmitting EM waves. The transition component 108 has a top surface 108A formed by the second horizontal metal layer 105 and a bottom surface 108C formed by the first horizontal metal layer 104. In addition, the transition component 108 has vertical components 108B and 108D that extend between the top surface 108A and the bottom surface 108C and couple the top and bottom surfaces to each other. In an example, the vertical components 108B, 108D are plated and have an approximately uniform thickness throughout. In an example, the vertical components 108B, 108D are composed of a group of through holes that are very close to each other (e.g., in contact with each other, such that each through hole is in contact with at least one other through hole), and any suitable technique including electroplating can be used to form such through holes. In an example, the top surface 108A and the bottom surface 108C and the vertical members 108B, 108D are made of copper, nickel, aluminum, gold or another suitable metal or alloy. The transition member 108 has a flared shape, which means that the vertical cross-sectional area of ​​the transition member 108 increases along the length of the transition member 108 from the conductive strip 106 to the waveguide 110. The transition member 108 has a horizontal cross-sectional area that is approximately equal throughout its thickness. The transition member 108 can be used to provide a gradual and uniform transition from the conductive strip 106 to the waveguide 110 so that the EM signal (wave) and therefore the impedance of the conductive strip 106 and the waveguide 110 are properly matched. If, for example, such a gradual taper is not introduced, the abrupt change in impedance will produce severe EM wave reflections (technically referred to as poor return loss) due to an unacceptable abrupt gradient or non-uniform gradient between the conductive strip 106 and the waveguide 110. This effect will be detrimental to the efficient propagation of the signal between the semiconductor die 98 and the horn antenna 112.

[0039] A waveguide 110 is coupled to the end of the transition member 108 that is away from the semiconductor die 98. A waveguide is defined as a metal tube that confines and transmits EM waves. The waveguide 110 has a vertical cross-sectional area that is approximately equal throughout its length. The waveguide 110 has a horizontal cross-sectional area that is approximately equal throughout its thickness. The waveguide 110 may be, for example, a rectangular prism. A top surface 110A of the waveguide 110 is formed by the second horizontal metal layer 105, and a bottom surface 110C of the waveguide 110 is formed by the first horizontal metal layer 104. The waveguide 110 includes vertical members 110B and 110D that extend between the top surfaces 110A, 110C and couple the top surfaces to each other. In an example, the vertical members 110B, 110D are plated and have an approximately uniform thickness throughout. In an example, the vertical members 110B, 110D are comprised of a set of vias that are in close proximity to one another (e.g., in contact with one another such that each via is in contact with at least one other via), and such vias may be formed using any suitable technique including electroplating. In an example, the top and bottom surfaces 110A, 110C and the vertical members 110B, 110D are comprised of copper, aluminum, nickel, gold, or another suitable metal or alloy.

[0040] A horn antenna is defined as a flared metal waveguide for guiding EM waves in a beam. The horn antenna 112 has a flared shape, wherein the smallest vertical cross-sectional area of ​​the horn antenna 112 is coupled to the distal end of the waveguide 110, and the largest vertical cross-sectional area of ​​the horn antenna 112 is flush or approximately flush with the edge 113 of the first horizontal metal layer 104. The horizontal cross-sectional area of ​​the horn antenna 112 is approximately uniform throughout the thickness of the horn antenna 112. In an example, the distal end of the horn antenna 112 is flush or approximately flush with the side surface of the semiconductor package 100 ( Figures 2A-2D 100 ). The horn antenna 112 has a top surface 112A formed by the second horizontal metal layer 105 and a bottom surface 112C formed by the first horizontal metal layer 104. Vertical members 112B, 112D extend between the first horizontal metal layer 104 and the second horizontal metal layer 105 and couple the first and second horizontal metal layers to each other. The horn antenna 112 can be used to provide a gradual and uniform transition from the waveguide 110 to the exterior of the semiconductor package 100 so that the EM signal (wave) does not experience severe reflections (return loss) that might otherwise be introduced into the EM signal due to, for example, an unacceptable abrupt gradient or non-uniform gradient between the waveguide 110 and the exterior of the semiconductor package 100. The horn antenna 112 terminates at a distal end having an aperture 112E.

[0041] As described above, the continuous metal structures in the semiconductor package 100 are impedance matched so that EM waves propagating across the boundaries of the structures are maximally transferred across the boundaries and minimally reflected back and away from the boundaries. More specifically, the continuous sequence of metal structures in the semiconductor package 100 includes a conductive component 102, a conductive strip 106, a transition component 108, a waveguide 110, and a horn antenna 112. Other sequences of these structures, replacements of structures, removals of structures, and / or additions of different structures are all contemplated and included within the scope of this specification. The conductive component 102 should be impedance matched to the conductive strip 106, which in turn should be impedance matched to the transition component 108, which in turn should be impedance matched to the waveguide 110, which in turn should be impedance matched to the horn antenna 112, which in turn should be impedance matched to the free space surrounding the semiconductor package 100. Failure to properly impedance match any continuous structure in this sequence may introduce inefficiencies due to increased reflection and / or reduced transfer of waves across the boundaries between any two structures or between the horn antenna 112 and the surrounding free space. More specifically, the impedance gradient between the first and second continuous impedance mismatch structures in the semiconductor package 100 causes the EM wave to be at least partially reflected back toward the source of the EM wave. The reflected EM wave causes an EM standing wave in the first structure, thereby wasting energy and increasing the standing wave ratio (SWR).

[0042] Impedance matching of continuous structures between the conductive component 102 and the free space surrounding the semiconductor package 100 can be achieved by controlling various properties of these structures, including shape, size (e.g., vertical cross-sectional size), material composition, and structure wall thickness, with the most effective way to manipulate impedance being by controlling the shape and size of each structure. For example, the conductive component 102 may have an impedance of 50 ohms, and the physical properties of the conductive tape 106 may be controlled to produce an impedance that is also 50 ohms. Thus, an EM signal propagating from the conductive component 102 to the conductive tape 106 will have little to no reflection back toward the conductive component 102. The vertical cross-sectional thickness of the conductive tape 106 may be manipulated to control the impedance of the conductive tape 106, thereby producing an example impedance of 50 ohms.

[0043] Not Figures 1A-1DEach structure shown in has a consistent impedance over its entire length. For example, a second structure that follows the first structure continuously and is located in front of the third structure continuously should have a consistent impedance over its entire length only when the first and third structures have the same impedance. For example, if the first and third structures have an impedance of 50 ohms, the second structure may also have a consistent impedance of 50 ohms along its entire length. However, if the first and third structures have different impedances, the second structure located between the first and third structures should have a gradual impedance gradient. For example, if the conductive strip 106 has an impedance of 50 ohms and the waveguide 110 has an impedance of 200 ohms, the transition component 108 should have an impedance that gradually changes from 50 ohms (at the connection point with the conductive strip 106) to 200 ohms (at the connection point with the waveguide 110). An excessive impedance gradient in the transition component 108 will exacerbate the inefficiency caused by the signal reflection described above.

[0044] In order to achieve the gradual impedance gradient in the transition member 108 described above, the transition member 108 has a flared shape, which means that the transition member 108 has a smaller vertical cross-sectional area at the connection point with the conductive strip 106 and a larger vertical cross-sectional area at the connection point with the waveguide 110, with a uniform taper in between. An overly sharp or steep taper is unacceptable because of the impedance gradient (and resulting inefficiency) it will introduce, so the taper length should be at least 5 to 8 times longer than the feature size of the smallest element in the elements to be impedance matched. In this example, the taper length of the transition portion 108 should be 5-8 times longer than the width of the conductive strip 106. The flaring of the transition member 108 may be accomplished by separating the top surface 108A and the bottom surface 108C from one another along the length of the transition member 108 (i.e., the top surface 108A and the bottom surface 108C are not parallel to one another) and / or by separating the vertical members 108B, 108D from one another along the length of the transition member 108 (i.e., the vertical members 108B, 108D are not parallel to one another).

[0045] The waveguide 110 is coupled to the distal end of the transition member 108 and has an approximately uniform vertical cross-sectional area along the length of the waveguide 110. The waveguide 110 can be used to carry the EM signal from the transition member 108 to the horn antenna 112, which means that the waveguide 110 can be used to traverse a portion of the length or width of the package 100 to facilitate providing the EM signal to the horn antenna 112. In applications where the EM signal is to traverse a long distance within the package, the use of a rectangular waveguide such as the waveguide 110 mitigates crosstalk and electromagnetic interference (EMI) effects. An advantage of the waveguide 110 is that the EM signal is completely isolated except at the ends of the waveguide 110. In addition, the waveguide 110 should be formed so that the cutoff frequency of the EM mode used to transmit the signal is higher than the operating frequency of the device. In the example, the mode used is the TE10 waveguide mode, and the cutoff frequency is defined by the width of the waveguide. Therefore, the width of the waveguide must be such that the cutoff frequency is higher than the operating frequency, otherwise the operational integrity of the waveguide 110 will be compromised. In the example, the waveguide 110 has an impedance of 200 ohms, thus matching the impedance of the distal end of the transition component 108. Because the physical properties of the waveguide 110 are consistent along the length of the waveguide 110, the impedance of the waveguide 110 is also consistent along the length of the waveguide 110. Therefore, if the impedance of the waveguide 110 is 200 ohms, the impedance of the proximal end of the horn antenna 112 must also be 200 ohms, otherwise inefficiencies will result, such as those described above. The proximal end of the horn antenna 112 is impedance matched to the waveguide 110 (e.g., 200 ohms). The impedance of free space is 377 ohms, and thus the horn antenna 112 has a flared shape that provides an impedance gradient of 200 ohms at the proximal end of the horn antenna 112 to 377 ohms at the distal end of the horn antenna 112. The physical properties of the horn antenna 112 are the same as those described above for the transition component 108, and therefore will not be repeated here.

[0046] In an example, the conductive strip 106 is entirely composed of plated metals such as copper, aluminum, nickel, or gold. In an example, the transition component 108, the waveguide 110, and the horn antenna 112 include plated metals such as copper, aluminum, nickel, or gold, with an internal space filled with a molding compound (e.g., epoxy). The conductive strip 106, the transition component 108, the waveguide 110, and the horn antenna 112 include low-conductivity metals to avoid ohmic losses, because poor conductors with higher resistivity will produce greater signal losses.

[0047] The conductive component 102 has a thickness ranging from 2000 um 2 Up to 50,000um 2The horizontal cross-sectional area of ​​, wherein an area below this range is disadvantageous because such an area may introduce high inductance that may be difficult to impedance match, and wherein an area above this range is disadvantageous because such an area may result in the semiconductor die being unacceptably large. The length of the conductive member 102 is in the range of 30um to 100um, a length below this range is impossible to manufacture, and a length above this range is disadvantageous due to high inductance levels. For the above ( Figure 1A The metal of the structure described in (a) must have a very low resistivity. This material can be copper, but other materials may be useful, such as aluminum, silver, gold, platinum, etc. Although EM waves travel in dielectric materials, the EM fields are induced by currents flowing in the metal structures. Specifically, at high frequencies, these currents flow in the outer surfaces of these metal parts due to the skin effect. Therefore, low resistivity in the metal is necessary.

[0048] Figure 1B is a front view of a semiconductor package 100 in various examples. Figure 1C are cross-sectional views of semiconductor package 100 in various examples. Figure 1D is a top perspective view of a semiconductor package 100 in various examples.

[0049] Figures 1A-1D The metal structures shown in the figure, specifically, the conductive component 102, the conductive tape 106, the waveguide 110 and the horn antenna 112, and the molding compound or other dielectric film covering and / or filling these metal structures together constitute a multi-layer packaging substrate. A multi-layer packaging substrate is defined as a substrate of a semiconductor package, wherein the substrate includes a plurality of metal layers formed by electroplating, and the substrate further includes a dielectric, such as a molding compound or film (e.g., The multiple metal layers form a network to route signals and / or power between various locations within the package 100. The multi-layer package substrate is different from a printed circuit board (PCB) because the multi-layer package substrate is located within the semiconductor package 100, while the PCB is external to the semiconductor package 100. The multi-layer package substrate contains multiple metal layers separated by solid tangible dielectrics, while the PCB may contain multiple layers of printed circuit boards that may not be separated by dielectric materials other than air. Therefore, in various examples, Figures 2A-2F Various views of such a multi-layer package substrate within semiconductor package 100 are provided.

[0050] Figure 2A 2 is a perspective view of a molded semiconductor package 100 that includes a directional antenna and an efficient signal path therein in various examples. In addition to explicitly showing the molding compound 200, Figure 2A The structure and Figure 1AThe structure of the molding compound 200 is the same. In an example, the molding compound 200 can be replaced by a dielectric film such as the ABF described above. This specification assumes the use of the molding compound 200, but a dielectric film or other material may be used. The molding compound 200 covers the semiconductor die 98, the conductive strip 106, the transition part 108, the waveguide 110, and the horn antenna 112. The molding compound 200 may also be present inside the transition part 108, the waveguide 110, and / or the horn antenna 112. The dielectric constant of the molding compound 200 or an alternative material (e.g., ABF) used to replace the molding compound 200 is in the range of 2.4 to 4, wherein a dielectric constant below this range is unfavorable because the size of the internal metal features will increase, and wherein a dielectric constant above this range is unfavorable because as the dielectric constant increases, the loss tangent also increases, causing the package to have unacceptable losses. Figure 2B is a front view of a semiconductor package 100 in various examples. Figure 2C is a side view of a semiconductor package 100 in various examples. Figure 2D is a top perspective view of a semiconductor package 100 in various examples.

[0051] In an example, various metal structures of semiconductor package 100 are plated (e.g., copper, nickel, aluminum, gold). These structures can be a single layer of plated metal. For example, Figure 2A As shown in FIG. 1 , the vertical component 110B can be a single layer of electroplated metal. In other examples, the vertical component 110B, similar to other vertical components of the semiconductor package 100 , includes an array of metal vias. Figure 2E 2 is a perspective view of a semiconductor package 100 having a vertical component formed by such metal vias 250. The metal vias 250 are of a contact type such that each metal via 250 is in contact with at least one other metal via 250. In order to prevent leakage of EM signals and the resulting low efficiency, the metal vias 250 are in contact with each other such that there is no gap between the metal vias 250. Figure 2E , metal via 250 is shown as being cylindrical, but any via shape is useful. Figure 2F 2 is a side view of a semiconductor package 100 having metal vias 250 in various embodiments.

[0052] Figure 3300 is a graph depicting the efficiency of a molded semiconductor package (e.g., semiconductor package 100) that includes a directional antenna and an efficient signal path therein in various examples. The x-axis depicts frequency in gigahertz (GHz), and the y-axis depicts S parameters in decibels (dB). Curve 302 depicts the insertion loss associated with energy propagating from the proximal end of the conductive strip 106 to the distal end of the horn antenna 112. As shown, at approximately 65 GHz, curve 302 has an insertion loss (S12) of approximately -5.8 dB, and this value approaches approximately S12 = -3 dB at higher frequencies. Curve 304 depicts the return loss associated with energy propagating from the proximal end of the conductive strip 106 to the distal end of the horn antenna 112, specifically, the degree of energy reflected back toward the proximal end of the conductive strip 106. As shown, at approximately 65 GHz, curve 304 has a return loss of approximately S11 = -4 dB, but at higher frequencies, such as about 81 GHz, curve 304 gains close to -13 dB. Curve 306 depicts the return loss associated with energy propagating from the distal end of the horn antenna 112 toward the proximal end of the conductive strip 106, specifically, the extent of energy reflected back toward the distal end of the horn antenna 112. As shown, at approximately 65 GHz, curve 306 has a return loss of approximately S22 = -4 dB, but at higher frequencies, such as about 81 GHz, curve 306 S22 approaches -15.8 dB. In general, performance improves as operating frequency increases, and thus the desired operating bandwidth of the semiconductor package 100 may range from approximately 78 GHz to 85 GHz.

[0053] Figure 4 1 is a perspective view of an electric field diagram depicting the efficiency of a molded semiconductor package that includes a directional antenna and an efficient signal path therein in various examples. The electric field diagram includes a plurality of sections that are labeled with numbers according to the metal structures of the semiconductor package 100 to which they correspond. For example, the section labeled 106 corresponds to the conductive strip 106; the section labeled 108 corresponds to the transition member 108; the section labeled 110 corresponds to the waveguide 110; and the section labeled 112 corresponds to the horn antenna 112. The electric field diagram sections of the conductive strip 106 show that the strength of the electric field is concentrated (strongest) within the conductive strip 106 and dissipated laterally from the conductive strip 106. Some of the electric field extends laterally beyond the conductive strip 106.

[0054] The electric field diagram section of the transition member 108 also shows that the strength of the electric field is concentrated (strongest) within the transition member 108 and dissipated laterally from the transition member 108. However, the transition member 108 is formed by electroplating to produce the specific structure described above, has solid vertical members 108B, 108D that are not susceptible to energy loss, and also has spaces filled with molding compound or another suitable material (e.g., ABF film) within the transition member 108. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive strip 106, and is smaller than that of a signal-carrying metal structure formed in a manner other than the transition member 108.

[0055] The electric field diagram section of the waveguide 110 shows that the intensity of the electric field is concentrated (strongest) within the waveguide 110 and dissipated laterally from the waveguide 110. However, the waveguide 110 is formed by electroplating to produce the specific structure described above, has solid vertical members 110B, 110D that are not susceptible to energy loss, and also has a space filled with molding compound or another suitable material (e.g., ABF film) within the waveguide 110. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive strip 106, and is smaller than that of a signal-carrying metal structure formed in a manner different from the waveguide 110.

[0056] The electric field diagram section of the horn antenna 112 shows that the strength of the electric field is concentrated (strongest) within the horn antenna 112 and dissipated laterally from the horn antenna 112. However, the horn antenna 112 is formed by electroplating to produce the specific structure described above, has solid vertical members 112B, 112D that are not susceptible to energy loss, and also has a space filled with molding compound or another suitable material (e.g., ABF film) within the horn antenna 112. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive tape 106, and is smaller than that of a signal-carrying metal structure formed in a manner different from the horn antenna 112.

[0057] Figure 5 is a side view of an electric field diagram depicting the efficiency of a molded semiconductor package (such as semiconductor package 100) containing a directional antenna and an efficient signal path therein in various examples. Figure 4 As shown in FIG. 1 , reference numerals 106 , 108 , 110 , and 112 correspond to vertical electric field distributions of the conductive strip 106 , the transition component 108 , the waveguide 110 , and the horn antenna 112 , respectively. Figure 5The electric field plots of 108 show that the particular structure of the conductive strip 106, transition member 108, waveguide 110, and horn antenna 112 limits energy inefficiencies by preventing significant vertical energy losses as EM waves propagate toward and through the horn antenna 112. Although the vertical energy losses in the distal section of the waveguide 110 and in the horn antenna 112 are more significant than the vertical energy losses in the proximal section of the conductive strip 106, transition member 108, and waveguide 110, the energy losses are still significantly less than the energy losses experienced by structures other than those described herein.

[0058] Figure 6 is a schematic diagram depicting the directivity of antennas in molded semiconductor packages (such as semiconductor package 100) in various examples. Specifically, Figure 6 An EM wave 600 is depicted propagating from the horn antenna 112 into free space outside the semiconductor package 100. The shading of the EM wave 600 illustrates the enhanced gain along the axis 602 as the EM wave 600 propagates away from the horn antenna 112, and furthermore, the EM wave 600 exhibits almost no propagation transverse to the axis 602. Thus, the EM wave 600 exhibits high directivity along the axis 602.

[0059] Fig. 7A 698 is a perspective view of a molded semiconductor package 698 that includes a directional antenna, an efficient signal path, and a grounded coplanar waveguide in various examples. More specifically, Fig. 7A The semiconductor package 698 of FIG. 6 is structurally identical to the semiconductor package 100 described above, except that the semiconductor package 698 includes a conductive member 700 coupled to a grounded coplanar waveguide (GCPW) 704 and a conductive member 702 coupled to a grounded coplanar waveguide (GCPW) 706. Each of the conductive members 700, 702 is coupled to a ground connection within the semiconductor die 98, and each of the GCPWs 704, 706 is coupled to ground by coupling to the first horizontal metal layer 104 (ground plane). In an example, the lateral edges of the GCPWs 704, 706 that are laterally farthest from the conductive tape 106 extend downward to couple to the first horizontal metal layer 104, but any portion of the GCPWs 704, 706 may be coupled to the first horizontal metal layer 104. Furthermore, the GCPWs 704, 706 may include any suitable metal (e.g., copper, aluminum, nickel, gold) and may be formed using, for example, an electroplating process. Additionally, the GCPWs 704, 706 may have any suitable shape, and the scope of this specification is not limited to Fig. 7A The specific shapes shown in . Figure 7B is a front view of a semiconductor package 698 in various embodiments. Figure 7C is a cutaway cross-sectional view of a semiconductor package 698 in various examples. Fig.7Dis a top perspective view of a semiconductor package 698 in various examples.

[0060] Fig. 8A 704, 706, is a perspective view of a semiconductor package 698 in various examples having an insulating material, such as molding compound 200, covering semiconductor die 98 and various depicted metal structures (including GCPW 704, 706) of semiconductor package 698. As described above, a film such as ABF may be used in place of molding compound 200. Other materials are also contemplated and are within the scope of this description. Figure 8B is a front view of a semiconductor package 698 in various embodiments. Figure 8C is a cutaway cross-sectional view of a semiconductor package 698 in various examples. Fig.8D is a top perspective view of a semiconductor package 698 in various examples.

[0061] Fig. 9 900 is a graph depicting the efficiency of a molded semiconductor package including a directional antenna, an efficient signal path, and a grounded coplanar waveguide in various examples. The x-axis depicts frequency in gigahertz (GHz), and the y-axis depicts S parameters in decibels (dB). Curve 902 depicts the insertion loss associated with energy propagating from the proximal end of the conductive strip 106 to the distal end of the horn antenna 112. As shown, at approximately 65 GHz, curve 902 has an insertion loss S12 of approximately -5.8 dB, and S12 approaches approximately -3 dB at higher frequencies. Curve 904 depicts the return loss associated with energy propagating from the proximal end of the conductive strip 106 to the distal end of the horn antenna 112, specifically, the degree of energy reflected back toward the proximal end of the conductive strip 106. As shown, at approximately 65 GHz, curve 904 has a return loss S11 of approximately -5 dB, but at higher frequencies (e.g., about 100 GHz), curve 904S11 approaches -15 dB. Curve 906 depicts the return loss associated with energy propagating from the distal end of the horn antenna 112 toward the proximal end of the conductive strip 106, specifically, the extent of energy reflected back toward the distal end of the horn antenna 112. As shown, at approximately 65 GHz, curve 906 has a return loss S22 of approximately -4.5 dB, but at higher frequencies (e.g., about 100 GHz), curve 906S22 approaches -13 dB. In general, performance improves as operating frequency increases, and thus the desired operating bandwidth of the semiconductor package 100 may be in the range from approximately 90 GHz to 100 GHz.

[0062] Fig.106 is a perspective view of an electric field diagram depicting the efficiency of semiconductor package 698 in various examples. The electric field diagram includes a plurality of sections, which are numbered according to the metal structures of semiconductor package 698 to which they correspond. For example, the sections labeled 106, 704, 706 correspond to conductive strip 106, GCPW 704, and GCPW 706; only the section labeled 106 corresponds to conductive strip 106; the section labeled 108 corresponds to transition member 108; the section labeled 110 corresponds to waveguide 110; and the section labeled 112 corresponds to horn antenna 112. The electric field diagram sections of conductive strip 106 and GCPW 704, 706 show that the strength of the electric field is concentrated (strongest) within conductive strip 106 and dissipated laterally from conductive strip 106. Some of the electric field extends laterally beyond conductive strip 106, but the extent of lateral energy leakage is reduced due to the presence of GCPW 704, 706.

[0063] The electric field plot section for only the conductive strip 106 shows that the strength of the electric field is concentrated (strongest) within the conductive strip 106 and dissipates laterally from the conductive strip 106. Some of the electric field extends laterally beyond the conductive strip 106.

[0064] The electric field diagram section of the transition member 108 also shows that the strength of the electric field is concentrated (strongest) within the transition member 108 and dissipated laterally from the transition member 108. However, the transition member 108 is formed by electroplating to produce the specific structure described above, has solid vertical members 108B, 108D that are not susceptible to energy loss, and also has spaces filled with molding compound or another suitable material (e.g., ABF film) within the transition member 108. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive strip 106, and is smaller than that of a signal-carrying metal structure formed in a manner other than the transition member 108.

[0065] The electric field diagram section of the waveguide 110 shows that the intensity of the electric field is concentrated (strongest) within the waveguide 110 and dissipated laterally from the waveguide 110. However, the waveguide 110 is formed by electroplating to produce the specific structure described above, has solid vertical members 110B, 110D that are not susceptible to energy loss, and also has a space filled with molding compound or another suitable material (e.g., ABF film) within the waveguide 110. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive strip 106, and is smaller than that of a signal-carrying metal structure formed in a manner different from the waveguide 110.

[0066] The electric field diagram section of the horn antenna 112 shows that the strength of the electric field is concentrated (strongest) within the horn antenna 112 and dissipated laterally from the horn antenna 112. However, the horn antenna 112 is formed by electroplating to produce the specific structure described above, has solid vertical members 112B, 112D that are not susceptible to energy loss, and also has a space filled with molding compound or another suitable material (e.g., ABF film) within the horn antenna 112. Therefore, as shown, the amount of lateral energy loss is smaller than that of the conductive tape 106, and is smaller than that of a signal-carrying metal structure formed in a manner different from the horn antenna 112.

[0067] Fig.11 is a perspective view of an electric field diagram depicting the efficiency of semiconductor package 698 in various examples. Numbers 106, 704 and 706, 106, 108, 110 and 112 correspond to conductive strip 106 with GCPW 704, 706, conductive strip 106 alone, transition member 108, waveguide 110 and horn antenna 112, respectively. Fig.11 The electric field diagram is along Fig.11 The illustrated metal structure is cut along the axial centerline and therefore does not reflect the electric field activity in areas outside the axial centerline. The electric field diagram illustrates that the specific structure of the conductive strip 106, transition member 108, waveguide 110, and horn antenna 112 limits energy inefficiency by preventing significant vertical energy losses as EM waves propagate toward and through the horn antenna 112 (relative to semiconductor packages that do not implement the specific metal structures described herein).

[0068] Fig.12 698 is a schematic diagram depicting the directivity of antennas in semiconductor package 698 in various examples. Specifically, Fig.12 An EM wave 1200 is depicted propagating from the horn antenna 112 into free space outside the semiconductor package 698. The shading of the EM wave 1200 illustrates the enhanced gain along the axis 1202 as the EM wave 1200 propagates away from the horn antenna 112, and further, the EM wave 1200 exhibits almost no propagation transverse to the axis 1202. Thus, the EM wave 1200 exhibits high directivity along the axis 1202.

[0069] Fig.13A and 13B is a process flow diagram of a method for manufacturing a semiconductor package including a directional antenna and an efficient signal path therein in various embodiments. Figures 13A-13B The process flow does not depict the actual fabrication of the specific metal structures of the semiconductor package 100, 698, but Figures 13A-13B The process flow of FIG. 69 does depict the manufacturing techniques for forming the metal structures of the semiconductor package 100 , 698 . Fig.14is a flow chart of a method 1400 for manufacturing a semiconductor package including a directional antenna and an efficient signal path therein in various embodiments. Figures 13A-13B and 14. The process flow begins by providing a metal carrier 1300 having a plating seed layer 1302 (e.g., copper) deposited thereon. The process flow then includes electroplating a metal layer 1304 on the metal carrier 1300. Any suitable metal may be used, such as copper, aluminum, nickel, or gold. The metal layer 1304 may have any shape, size, or configuration. For example, the metal layer 1304 may have the form of the first horizontal metal layer 104 described above. Fig.14 As depicted, method 1400 begins by plating a first horizontal metal ground layer on a carrier (1402).

[0070] Figures 13A-13B The process flow then includes electroplating vertical members 1306 on metal layer 1304. Any suitable metal may be used, such as copper, aluminum, nickel, or gold. Vertical members 1306 may have any shape, size, or configuration. For example, vertical members 1306 may have the form of vertical members such as vertical members 108B, 108D, 110B, 110D, 112B, and 112D described above. Fig.14 As depicted, method 1400 includes plating a plurality of vertical features on a first horizontal metal ground layer (1404).

[0071] Figures 13A-13B The process flow then includes applying a molding compound 1308 or other suitable insulating material (e.g., ABF film), but this description assumes that a molding compound is applied. Fig.14 As depicted, method 1400 includes applying a first molding compound to a first horizontal metal ground layer and a plurality of vertical features (1406).

[0072] Figures 13A-13B The process flow includes grinding the molding compound 1308, for example, until the top surface of the vertical component 1306 is flush with the top surface of the molding compound 1308. Fig.14 As depicted, method 1400 includes grinding at least a portion of the molding compound and the plurality of vertical features (1408).

[0073] Figures 13A-13B The process flow includes electroplating another metal layer 1312 (a seed layer for any electroplating performed after electroplating metal layer 1304 is not explicitly depicted, but may be applied as desired). Any suitable metal may be used, such as copper, aluminum, nickel, or gold. Metal layer 1312 may have any shape, size, or configuration. For example, metal layer 1312 may be in the form of second horizontal metal layer 105 described above. Fig.14 As depicted, method 1400 includes plating a second horizontal metal layer on a plurality of vertical features (1410).

[0074] Figures 13A-13B The process flow includes applying a molding compound 1316 (or another suitable insulating material, such as an ABF film) to the metal layer 1312. Fig.14 As depicted, method 1400 includes applying a second molding compound to the second horizontal metal layer (1412).

[0075] Figures 13A-13B The process flow includes grinding the molding compound 1316 until the top surface of the molding compound 1316 is flush with the top surface of the metal layer 1312 (and removing the carrier 1300). Fig.14 As shown, method 1400 includes grinding at least portions of the second molding compound and the second horizontal metal layer (1414).

[0076] The method 1400 may also include coupling the semiconductor die to the second horizontal metal layer ( 1416 ) and applying a third molding compound (eg, molding compound 200 ) to the second molding compound and the semiconductor die ( 1418 ) to produce the semiconductor package 100 and / or the semiconductor package 698 described above.

[0077] The term "coupled" is used throughout this specification. The term may encompass connections, communications, or signal paths that enable a functional relationship consistent with this description. For example, if device A generates a signal to control device B to perform an action, then: in a first instance, device A is coupled to device B; or in a second instance, device A is coupled to device B through an intermediate component C, provided that the intermediate component C does not substantially change the functional relationship between device A and device B, so that device B is controlled by device A via the control signal generated by device A.

[0078] A circuit or device described herein as including certain components may actually be coupled to those components to form the described circuit system or device. For example, a structure described as including one or more semiconductor elements (e.g., transistors), one or more passive elements (e.g., resistors, capacitors, and / or inductors), and / or one or more sources (e.g., voltage and / or current sources) may actually include only semiconductor elements within a single physical device (e.g., a semiconductor die and / or an integrated circuit (IC) package), and may be coupled to at least some of the passive elements and / or sources during or after manufacture, such as by an end user and / or a third party, to form the described structure.

[0079] The use of the term "ground" in the foregoing description includes chassis ground, ground wire ground, floating ground, virtual ground, digital ground, universal ground, and / or any other form of ground connection that is applicable or suitable for the teachings of this specification. Unless otherwise stated, "about," "approximately," or "substantially" preceding a parameter means within + / - 10% of the parameter. Modifications of the described examples are possible, and other examples are possible, within the scope of the claims.

Claims

1. A semiconductor package, comprising: Semiconductor die; a conductive member coupled to the semiconductor die; as well as A multi-layer packaging substrate comprising: a first horizontal metal layer for providing a ground connection; a second horizontal metal layer above the first horizontal metal layer; a vertical member coupled to the first and second horizontal metal layers; and a molding compound covering the first and second horizontal metal layers and the vertical component, The first horizontal metal layer, the second horizontal metal layer and the vertical component together form a structure including a conductive strip coupled to the conductive component, a transition component coupled to the conductive strip, a waveguide coupled to the transition component, and a horn antenna coupled to the waveguide.

2. The semiconductor package of claim 1, wherein the transition member has a flared shape having a first end and a second end narrower than the first end, the second end coupled to the conductive strip, and the first end coupled to the waveguide. 3 . The semiconductor package of claim 1 , wherein the conductive strip, the transition member, the waveguide, and the horn antenna are impedance matched. 4 . The semiconductor package of claim 1 , wherein the vertical member comprises first and second monolithic vertical members forming portions of the transition member, the waveguide, and the horn antenna. 5 . The semiconductor package of claim 1 , wherein the vertical member comprises a plurality of through-holes, each through-hole of the plurality of through-holes being in contact with at least one other through-hole of the plurality of through-holes. The semiconductor package of claim 1 , wherein the waveguide is a rectangular prism. 7 . The semiconductor package of claim 1 , wherein at least some of the molding compound is located inside the horn antenna, the waveguide, and the transition member.

8. A semiconductor package, comprising: Semiconductor die; a conductive member coupled to the semiconductor die and extending away from the semiconductor die; as well as A multi-layer packaging substrate comprising: a first horizontal metal layer for providing a ground connection; a second horizontal metal layer above the first metal layer; a vertical member coupled to the first and second horizontal metal layers; and a molding compound contacting the first and second horizontal metal layers and portions of the vertical component, wherein: The first horizontal metal layer forms a conductive strip coupled to the conductive member and configured to direct electromagnetic waves away from the conductive member; The first and second horizontal metal layers and the vertical member form a transition member coupled to the conductive strip, the transition member having a flared shape and configured to direct the electromagnetic wave away from the conductive strip, The first and second horizontal metal layers and the vertical member form a waveguide coupled to the transition member, the waveguide having a rectangular prism shape and configured to guide the electromagnetic wave away from the transition member, The first and second horizontal metal layers and the vertical member form a horn antenna coupled to the waveguide and configured to guide the electromagnetic wave from the waveguide to a predetermined direction. 9 . The semiconductor package of claim 8 , wherein the transition member includes a first end coupled to the conductive strip and a second end coupled to the waveguide, the first end being narrower than the second end.

10. The semiconductor package of claim 8, wherein the conductive strip, the transition member, and the waveguide and the horn antenna are impedance matched.

11. The semiconductor package of claim 8, wherein the vertical member comprises a monolithic vertical member forming part of the transition member, the waveguide, and the horn antenna. 12 . The semiconductor package of claim 8 , wherein the vertical member comprises a plurality of through-holes, each through-hole of the plurality of through-holes being in contact with at least one other through-hole of the plurality of through-holes.

13. The semiconductor package of claim 8, wherein at least some of the molding compound is located inside the horn antenna, the waveguide, and the transition member.

14. A method for manufacturing a semiconductor package, comprising: The multi-layer packaging substrate is formed by the following operations: Plating a first horizontal metal ground layer on the carrier; Plating a plurality of vertical components on the first horizontal metal ground layer; applying a first molding compound to the first horizontal metal ground layer and the plurality of vertical components; grinding at least a portion of the molding compound and the plurality of vertical members; plating a second horizontal metal layer on the plurality of vertical components; applying a second molding compound to the second horizontal metal layer; as well as grinding at least a portion of the second molding compound and the second horizontal metal layer; coupling a semiconductor die to the second horizontal metal layer; as well as applying a third molding compound to the second molding compound and the semiconductor die, Wherein the first horizontal metal ground layer, the plurality of vertical components and the second horizontal metal layer form a structure including a conductive strip coupled to the semiconductor die and a plurality of impedance matching components of different shapes configured to guide electromagnetic waves in a predetermined direction. 15 . The method of claim 14 , wherein plating the plurality of vertical features comprises plating a plurality of through-holes, each through-hole of the plurality of through-holes being in contact with another through-hole of the plurality of through-holes.

16. The method of claim 14, wherein plating the plurality of vertical members comprises plating a monolithic vertical member, the plurality of impedance matched components comprising the monolithic vertical member.

17. The method of claim 14, wherein the plurality of impedance-matched components of different shapes include transition members having flared shapes, waveguides, and horn antennas.

18. The method of claim 17, wherein the transition member having the flared shape has a first end coupled to the conductive strip and a second end coupled to the waveguide, the second end being wider than the first end.

19. The method of claim 17, wherein the waveguide is shaped as a rectangular prism.

20. The method of claim 14, further comprising forming a grounded coplanar waveguide having first and second components, the conductive strip being positioned between the first component and the second component.

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