Semiconductor device with waveguide and method thereof

Abstract

The present disclosure relates to semiconductor devices having waveguides and methods thereof. A method of manufacturing a semiconductor device is provided. The method includes forming an assembly including placing a semiconductor die and a transmitter structure on a carrier substrate, encapsulating at least a portion of the semiconductor die and the transmitter structure, and applying a redistribution layer on a surface of the semiconductor die and a surface of the transmitter structure to connect bond pads of the semiconductor die with antenna transmitters of the transmitter structure. The assembly is attached to a substrate, and a waveguide overlapping the assembly is attached to the substrate. The waveguide structure is physically separated from the assembly.

Description

Technical Field

[0001] This disclosure generally relates to semiconductor device packaging, and more specifically, to a semiconductor device having a waveguide and a method of forming the same. Background Technology

[0002] The trend of installing radar systems in vehicles such as cars, trucks, and buses is growing, enhancing drivers' awareness of objects around their vehicles. When a vehicle approaches an object (e.g., other cars, pedestrians, or obstacles), or when an object approaches the vehicle, drivers cannot always detect the object and take the necessary intervention to avoid a collision. Automotive radar systems installed in vehicles can detect the presence of objects, including other vehicles nearby, and provide timely information to the driver, enabling them to take possible interventions. However, such automotive radar systems can significantly impact vehicle costs. Summary of the Invention

[0003] Generally, a method of manufacturing a semiconductor device is provided, the method comprising: forming an assembly, including: placing a semiconductor die and a transmitter structure on a carrier substrate, the transmitter structure including an antenna transmitter; encapsulating at least a portion of the semiconductor die and the transmitter structure; applying a redistribution layer on a first main surface of the semiconductor die and a first main surface of the transmitter structure, the bonding pads of the semiconductor die being connected to the antenna transmitter through the redistribution layer; attaching the assembly to the substrate; and attaching a waveguide structure to the substrate, the waveguide structure overlapping with and physically separated from the assembly. The transmitter structure may be formed having a cavity, the antenna transmitter being located on the bottom surface of the cavity. Attaching the waveguide structure to the substrate may further include extending sidewalls of openings in the waveguide structure into the cavity to substantially surround the antenna transmitter. The size of the openings in the waveguide structure may be configured for propagating millimeter-wave signals. The method further includes forming a conductive ring structure substantially surrounding the antenna transmitter, the outer sidewalls of the conductive ring structure being spaced apart from the sidewalls of the cavity to form a channel between the conductive ring structure and the sidewalls of the cavity. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure into a channel formed between the conductive ring structure and the sidewalls of the cavity. The method may further include back-side grinding of the assembly to expose conductive paths that substantially surround the antenna transmitter; and attaching the conductive ring structure to the exposed conductive paths. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure to substantially surround the conductive ring structure. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure to substantially surround the antenna transmitter, with the conductive ring structure surrounding the extended sidewalls of the opening.

[0004] In another embodiment, a semiconductor device is provided, the semiconductor device comprising: a printed circuit board (PCB) having a top-side surface; a package assembly attached to the PCB at the top-side surface, the package assembly including a package substrate having a first main surface and a second main surface; a semiconductor die having an active surface and a back-side surface, the semiconductor die being attached to the package substrate at the first main surface; a transmitter structure attached to the package substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die through the package substrate; and an epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and a waveguide structure attached to the PCB at the top-side surface, the waveguide structure overlapping with and physically separated from the package assembly. The package substrate may be characterized as an add-on substrate including a redistribution layer configured to couple bonding pads on the active surface of the semiconductor die to the antenna transmitter. The waveguide structure may be configured and arranged for propagating millimeter-wave signals. The transmitter structure may be formed having a cavity, with the antenna transmitter located on the bottom surface of the cavity. The waveguide structure may include a waveguide opening having a sidewall portion extending into the cavity and substantially surrounding the antenna transmitter. The transmitter structure may additionally include a conductive ring structure substantially surrounding the antenna transmitter, the outer wall of the conductive ring structure being spaced apart from the sidewall of the cavity to form a channel between the conductive ring structure and the sidewall of the cavity. The waveguide structure may include a waveguide opening having a sidewall portion extending into the channel formed between the conductive ring structure and the sidewall of the cavity.

[0005] In another embodiment, a semiconductor device is provided, the semiconductor device including a printed circuit board (PCB) having a top side surface; a packaged semiconductor device attached to the PCB at the top side surface, the packaged semiconductor device including a packaged substrate having a first main surface and a second main surface; a semiconductor die having an active surface and a back side surface, the semiconductor die being attached to the packaged substrate at the first main surface; a transmitter structure attached to the packaged substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die through a conductive feed of the packaged substrate; and an epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and a waveguide structure attached to the PCB at the top side surface, the waveguide structure overlapping the packaged semiconductor device, waveguide openings of the waveguide structure having sidewalls substantially surrounding the antenna transmitter, the waveguide structure being physically separated from the packaged semiconductor device. The transmitter structure may be formed having a cavity, with the antenna transmitter located on the bottom surface of the cavity. Sidewall portions of the waveguide openings may extend into the cavity and substantially surround the antenna transmitter. The transmitter structure may additionally include a conductive ring structure that substantially surrounds the antenna transmitter and is spaced apart from the sidewalls of the cavity to form a channel between the conductive ring structure and the sidewalls of the cavity, with the sidewall portion of the waveguide opening extending into the channel formed between the conductive ring structure and the sidewalls of the cavity. Attached Figure Description

[0006] The invention is illustrated by way of example and is not limited to the accompanying drawings, in which the same reference numerals indicate similar elements. Elements in the drawings are shown for simplicity and clarity, and are not necessarily drawn to scale.

[0007] Figures 1 to 4 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 5 Example semiconductor device with waveguide AA.

[0008] Figure 5 A plan view is shown in the embodiment. Figure 4 An example semiconductor device with a waveguide during the manufacturing stage is depicted in the image.

[0009] Figure 6 and Figure 7 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 8 Alternative example semiconductor devices with waveguides for line BB.

[0010] Figure 8 A plan view is shown in the embodiment. Figure 7 An example semiconductor device with a waveguide during the manufacturing stage is depicted in the image.

[0011] Figures 9 to 11 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 12 Alternative example semiconductor devices with waveguides for the line CC.

[0012] Figure 12 A plan view is shown in the embodiment. Figure 11 An example semiconductor device with a waveguide during the manufacturing stage is depicted in the image.

[0013] Figures 13 to 15 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 16 Alternative example semiconductor devices with waveguides for line DD.

[0014] Figure 16 A plan view is shown in the embodiment. Figure 15 An example semiconductor device with a waveguide during the manufacturing stage is depicted in the image. Detailed Implementation

[0015] Generally, a semiconductor device including a package assembly is provided, the package assembly being attached to a common substrate together with an overlapping waveguide structure. The waveguide structure is physically separated from the package assembly. A semiconductor die and a transmitter structure are encapsulated on the package substrate to form the package assembly. The waveguide structure includes a waveguide opening above the antenna transmitter of the transmitter structure, thereby allowing the propagation of radio frequency (RF) signals. By physically separating the overlapping waveguide structure from the package assembly, package stress can be reduced and reliability improved, while achieving low-loss RF signal performance within a compact footprint.

[0016] Figure 1 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 5 An example component of an example semiconductor device 100 with a waveguide is shown. At this stage of manufacturing, the components of the semiconductor device 100 include a semiconductor die 102 placed on a carrier substrate 104 and transmitter structures 106 and 108.

[0017] In this embodiment, transmitter structures 106 and 108 are each formed as multilayer laminated structures having cavities (e.g., cavities 112 and 114). For example, transmitter structure 106 includes conductive layers 122 and 130 (e.g., metal or other conductive material layers) separated by a non-conductive material 120 (e.g., FR-4, ceramic). Contacts 124 and through-holes 126 provide a conductive connection between end pads 132 and conductive layers 122 and 130 at the bottom surface of transmitter structure 106. Cavity 112 includes an antenna transmitter 116 located at the bottom surface of cavity 112. Similarly, cavity 114 includes an antenna transmitter 118 located at the bottom surface of cavity 114. Antenna transmitter 116 is connected to end pad 134 at the bottom surface of transmitter structure 106 via interconnecting contacts and through-holes (e.g., contacts 124, through-holes 126). A through-hole plug 128 may be incorporated into the through-hole 126 to provide additional strength and rigidity. In this embodiment, the conductive layer 122 and the interconnecting contacts 124 are configured and arranged to act as a conductive wall or fence that substantially surrounds the antenna transmitter 116. In some embodiments, it may be necessary to connect the conductive wall or fence to a ground power supply or other power supply. In this embodiment, the conductive layer 130 is configured and arranged to act as a signal reflector located below the antenna transmitter 116 and substantially surrounds the through-hole that interconnects the antenna transmitter 116 with the end pad 134. In some embodiments, it may be necessary to form the signal reflector on a next conductive layer immediately below the antenna transmitter 116.

[0018] Semiconductor die 102 has an active surface (e.g., a main surface having a circuit system) and a back-side surface (e.g., a main surface opposite the active surface). For example, semiconductor die 102 includes bonding pads 110 at the active surface, which are configured to be connected to antenna transmitters 116 and 118 via a redistribution layer (RDL). Semiconductor die 102 can be formed of any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium nitride, etc. Semiconductor die 102 can additionally include any digital circuitry, analog circuitry, RF circuitry, memory, signal processor, MEMS, sensor, etc., and combinations thereof.

[0019] Figure 2 A simplified cross-sectional view illustrates an example component in a subsequent manufacturing stage according to an embodiment. In this manufacturing stage, the components of the semiconductor device 100 include an encapsulation (e.g., epoxy material) 204 that at least partially encapsulates a semiconductor die 102 and emitter structures 106 and 108 placed on a carrier substrate 104. In this embodiment, the semiconductor die 102 and emitter structures 106 and 108 are overmolded with the epoxy material encapsulation using a thin-film assisted molding (FAM) process. A FAM tool 202 contacts the top surfaces of the emitter structures 106 and 108 during molding to keep predetermined portions (e.g., cavities 112 and 114) free of encapsulation (e.g., unencapsulated).

[0020] Figure 3A simplified cross-sectional view illustrates an example component in a subsequent manufacturing stage according to an embodiment. In this manufacturing stage, component 302 includes an encapsulation 204 that at least partially encapsulates semiconductor die 102 and transmitter structures 106 and 108, as well as an RDL substrate 304 and a ball connector 310. After removing the carrier substrate 104, the RDL substrate 304 is applied to the resulting exposed bottom surfaces, which include the exposed active surfaces of semiconductor die 102 and the exposed bottom surfaces of transmitter structures 106 and 108. Conductive feeds 306 and 308 are formed in the RDL substrate 304, between bonding pad 110 and end pad 134, to interconnect semiconductor die 102 and antenna transmitters 116 and 118, respectively. After applying the RDL substrate 304, a conductive ball connector 310 (e.g., solder balls) is attached to the bottom surface of the RDL substrate 304. For example, the ball connector 310 is configured and arranged to provide a conductive connection between component 302 and a printed circuit board (PCB). The ball connector 310 can be any suitable conductive structure, such as solder balls, gold studs, copper pillars, etc., to connect the conductive components of component 302 to the PCB. In this embodiment, the RDL substrate 304 is formed as a build-up substrate including a redistribution layer. In some embodiments, the RDL substrate 304 can be formed as a preformed substrate including a redistribution layer. In other embodiments, the ball connector 310 can be directly attached to end pads 132, 134 and bonding pad 110 for connection to the PCB, for example, without using the RDL substrate.

[0021] Figure 4 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 5 Example semiconductor device 100 with waveguides. In this manufacturing stage, semiconductor device 100 includes a component 302 attached to a common substrate 404 and an overlapping waveguide structure 402. With component 302 and overlapping waveguide structure 402 attached to substrate 404, waveguide structure 402 is physically separated from component 302. For example, waveguide structure 402 does not physically contact component 302. In this embodiment, substrate 404 may be a PCB or, for example, another multilayer substrate configured to connect to other components of the system.

[0022] Waveguide structure 402 includes a waveguide 406 (e.g., a waveguide opening) and is attached to a substrate 404 at an interface 408. For example, screws, alignment pins, adhesives, and combinations thereof can be used to attach waveguide structure 402 to substrate 404 at interface 408. In this embodiment, waveguide structure 402 is formed of a conductive material, such as a metal (e.g., aluminum, copper), a non-conductive material coated with a conductive material, other conductive materials, or combinations thereof. Waveguide 406 is formed as a waveguide opening in waveguide structure 402 through which antenna transmitters 116 and 118 are exposed. In this embodiment, waveguide opening 406 includes sidewall portions 410 extending downward into cavities 112 and 114 and substantially surrounding antenna transmitters 116 and 118, respectively. The dimensions (e.g., width, length) of waveguide 406 can be configured for propagating signals having a desired wavelength (e.g., radar, millimeter-wave signals, 30 GHz to 300 GHz). For example, a waveguide can be configured to propagate (e.g., transmit) a radar signal with a frequency of 77 GHz. Because a 77 GHz signal has a wavelength of approximately 4 mm, the waveguide is configured to have a width of approximately 2 mm, or half the desired wavelength.

[0023] Figure 5 A plan view is shown in the embodiment. Figure 4 An example semiconductor device 100 with a waveguide is depicted during a manufacturing stage. In this manufacturing stage, the semiconductor device 100 includes a component (302) attached to a common substrate (404) and an overlapping waveguide structure 402. The semiconductor die 102 below is shown in dashed outline, marked 102, for reference. Figures 1 to 4 The illustrated example manufacturing stage shows a cross-sectional view of a semiconductor device 100 including waveguide 406, taken along line AA. Waveguide 406 is formed as a waveguide opening in waveguide structure 402, through which the non-conductive material 120 of antenna transmitters 116 and 118 and transmitter structures 106 and 108 is exposed.

[0024] Figure 6 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 8This is an example component of an example semiconductor device 200 with a waveguide. During this fabrication phase, component 600 includes an encapsulation 638 that at least partially encapsulates semiconductor die 602 and transmitter structures 606 and 608, as well as an RDL substrate 604 and a ball connector 644. Conductive feeds 640 and 642 are formed in the RDL substrate 604 between bonding pad 610 and end pad 634 to interconnect semiconductor die 602 with antenna transmitters 616 and 618, respectively. Conductive ball connector 644 (e.g., solder balls) is attached to the bottom surface of the RDL substrate 604. For example, ball connector 644 is configured and arranged to provide a conductive connection between component 600 and a PCB. Ball connector 644 can be any suitable conductive structure, such as solder balls, gold studs, copper studs, etc., to connect conductive parts of component 600 to the PCB. In this embodiment, RDL substrate 604 is formed as a build-up substrate including a redistribution layer. In some embodiments, the RDL substrate 604 may be formed as a pre-shaped substrate including a redistribution layer. In other embodiments, the ball connector 644 may be directly attached to the end pads 632-634 and the bonding pad 610 for example, to connect to a PCB without using the RDL substrate.

[0025] In this embodiment, transmitter structures 606 and 608 are each formed as multilayer laminated structures having cavities (e.g., cavities 612 and 614). For example, transmitter structure 606 includes a conductive layer 622 (e.g., a layer of metal or other conductive material) separated by a non-conductive material 620 (e.g., FR-4, ceramic). Contact points 624 and channels 625 provide a conductive connection between end pads 632 and the conductive layer 622 at the bottom surface of transmitter structure 606. Cavity 612 includes an antenna transmitter 616 and surrounds a conductive pad 630 located at the bottom surface of cavity 612. Similarly, cavity 614 includes an antenna transmitter 618 and surrounds a conductive pad located at the bottom surface of cavity 614. A conductive ring 626 is attached to the conductive pad 630 via a conductive connector 628 (e.g., solder, conductive adhesive, anisotropic conductive film). A channel 636 is formed in cavity 612 between the outer wall of conductive ring 626 and the side wall of cavity 612. Antenna transmitter 616 is connected to end pad 634 at the bottom surface of transmitter structure 606 via interconnecting contacts and through-holes. In this embodiment, conductive layer 622 and interconnecting contacts 624 are configured and arranged to act as conductive walls or fences that substantially surround the sidewalls of cavity 612. In some embodiments, it may be necessary to connect the conductive walls or fences to a ground power supply or other power supply.

[0026] Semiconductor die 602 has an active surface (e.g., a main surface having a circuit system) and a back-side surface (e.g., a main surface opposite the active surface). Semiconductor die 602 includes bonding pads 610 located on the active surface, the bonding pads 610 being configured to connect, for example, to antenna transmitters 616 and 618 via an RDL. Semiconductor die 602 can be formed from any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium nitride, etc. Semiconductor die 602 can additionally include any digital circuitry, analog circuitry, RF circuitry, memory, signal processor, MEMS, sensor, etc., and combinations thereof.

[0027] Figure 7 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 8 Example semiconductor device 200 of line BB. In this manufacturing stage, semiconductor device 200 includes component 600 and overlapping waveguide structure 702 attached to a common substrate 704. With component 600 and overlapping waveguide structure 702 attached to substrate 704, waveguide structure 702 is physically separated from component 600. For example, waveguide structure 702 does not physically contact component 600. In this embodiment, substrate 704 may be located on a PCB or, for example, on other multilayer substrates configured to connect to other components of the system.

[0028] Waveguide structure 702 includes a waveguide 706 (e.g., a waveguide opening) and is attached to a substrate 704 at an interface 708. For example, screws, alignment pins, adhesives, and combinations thereof can be used to attach waveguide structure 702 to substrate 704 at interface 708. In this embodiment, waveguide structure 702 is formed of a conductive material such as a metal (e.g., aluminum, copper), other conductive materials, or combinations thereof. Waveguide 706 is formed as a waveguide opening in waveguide structure 702 through which antenna transmitters 616 and 618 are exposed. In this embodiment, waveguide opening 706 includes a sidewall portion 710 extending downward into a channel 636 in cavities 612 and 614, respectively formed between the outer sidewall of conductive ring 626 and the sidewalls of cavities 612 and 614. The dimensions (e.g., width, length) of waveguide 706 can be configured for propagating signals having a desired wavelength (e.g., radar, millimeter-wave signals, 30 GHz to 300 GHz).

[0029] Figure 8 A plan view is shown in the embodiment. Figure 7 The image depicts an example semiconductor device 200 with a waveguide during a manufacturing stage. In this manufacturing stage, the semiconductor device 200 includes a component 600 attached to a common substrate (704) and an overlapping waveguide structure 702. The semiconductor die 602 below is shown in a dashed outline, labeled 602, for reference. Figure 7 and Figure 8 The illustrated example manufacturing stage shows a cross-sectional view of a semiconductor device 200 with a waveguide, including waveguide 706, taken along line BB. Waveguide 706 is formed as a waveguide opening in waveguide structure 702, through which antenna transmitters 616 and 618, conductive ring 626, and non-conductive material 620 of transmitter structures 606 and 608 are exposed.

[0030] Figure 9 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 12 An example component of an example semiconductor device 300 with a waveguide is described. During this manufacturing stage, the component of the semiconductor device 300 includes an encapsulation (e.g., epoxy material) 928 that encapsulates a semiconductor die 902 and emitter structures 906 and 908 placed on a carrier substrate 904. In this embodiment, the semiconductor die 902 and emitter structures 906 and 908 are overmolded with an epoxy material encapsulation.

[0031] In this embodiment, transmitter structures 906 and 908 are formed as laminated structures having antenna transmitters 914 and 916 located on the top surfaces of transmitter structures 906 and 908, respectively. For example, transmitter structure 906 includes conductive interconnects 918 and 920 (e.g., metal or other conductive materials) separated by a non-conductive material 912 (e.g., FR-4, ceramic). Conductive interconnect 918 provides a conductive connection between an end pad 922 and a conductive ball connector 926 (e.g., solder ball) on the bottom surface of transmitter structure 906. Antenna transmitter 914 is connected to end pad 924 on the bottom surface of transmitter structure 906 via conductive interconnect 920. Conductive interconnect 918 and conductive ball connector 926 are configured and arranged to substantially surround antenna transmitter 914 and conductive interconnect 920.

[0032] Semiconductor die 902 has an active surface (e.g., a main surface having a circuit system) and a back-side surface (e.g., a main surface opposite the active surface). Semiconductor die 902 includes bonding pads 910 located on the active surface, the bonding pads 910 being configured to connect, for example, to antenna transmitters 914 and 916 via an RDL. Semiconductor die 902 can be formed from any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium nitride, etc. Semiconductor die 902 can additionally include any digital circuitry, analog circuitry, RF circuitry, memory, signal processor, MEMS, sensor, etc., and combinations thereof.

[0033] Figure 10A simplified cross-sectional view is shown of an example component in a subsequent manufacturing stage according to an embodiment. In this manufacturing stage, component 1000 includes an encapsulation 928 that at least partially encapsulates a semiconductor die 902 and emitter structures 906 and 908, as well as an RDL substrate 1004 and a ball connector 1016.

[0034] In this embodiment, a back-side grinding operation is performed on component 1000 to expose portions of the ball connector 926 of transmitter structures 906 and 908 and the back surface of semiconductor die 902. A conductive ring 1008 is attached via a conductive connector 1006 (e.g., solder, conductive adhesive, anisotropic conductive film) to the conductive path formed through the exposed portions of the ball connector 926. The conductive ring 1008 is configured and arranged to act as a conductive wall or fence that substantially surrounds antenna transmitter 914 and forms cavity 1010. Similarly, the conductive ring substantially surrounds antenna transmitter 916 and forms cavity 1012. In some embodiments, it may be necessary to connect the conductive wall or fence to a ground power supply or other power supply.

[0035] After removing the carrier substrate 904, an RDL substrate 1004 is applied to the resulting exposed bottom surfaces, which include the exposed active surfaces of the semiconductor die 902 and the exposed bottom surfaces of the transmitter structures 906 and 908. A conductive feed 1014 is formed in the RDL substrate 1004 between bonding pads 910 and end pads 924 to interconnect the semiconductor die 902 with antenna transmitters 914 and 916, respectively. After applying the RDL substrate 1004, a conductive ball connector 1016 (e.g., a solder ball) is attached to the bottom surface of the RDL substrate 1004. For example, the ball connector 1016 is configured and arranged to provide a conductive connection between the assembly 1000 and a printed circuit board (PCB). The ball connector 1016 can be any suitable conductive structure, such as a solder ball, gold stud, copper pillar, etc., to connect conductive parts of the assembly 1000 to the PCB. In this embodiment, the RDL substrate 1004 is formed as a build-up substrate including a redistribution layer. In some embodiments, the RDL substrate 1004 may be formed as a pre-shaped substrate including a redistribution layer. In other embodiments, the ball connector 1016 may be directly attached to the end pads 922, 924 and the bonding pad 910 for example, to connect to a PCB without using the RDL substrate.

[0036] Figure 11 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 12An example semiconductor device 300 with a waveguide is described. In this manufacturing stage, the semiconductor device 300 with a waveguide includes a component 1000 attached to a common substrate 1104 and an overlapping waveguide structure 1102. With the component 1000 and the overlapping waveguide structure 1102 attached to the substrate 1104, the waveguide structure 1102 is physically separated from the component 1000. For example, the waveguide structure 1102 does not physically contact the component 1000. In this embodiment, the substrate 1104 may be a PCB or, for example, another multilayer substrate configured to connect to other components of the system.

[0037] Waveguide structure 1102 includes waveguide 1106 (e.g., waveguide opening) and is attached to substrate 1104 at interface 1108. Waveguide structure 1102 can be attached to substrate 1104 at interface 1108 using screws, alignment pins, adhesives, and combinations thereof. In this embodiment, waveguide structure 1102 is formed of a conductive material such as a metal (e.g., aluminum, copper), other conductive materials, or combinations thereof. Waveguide 1106 is formed as a waveguide opening in waveguide structure 1102, through which the surfaces of conductive ring 1008 and encapsulation 928 above antenna transmitters 914 and 916 are exposed. In this embodiment, waveguide opening 1106 is configured and arranged to substantially surround conductive ring, which substantially surrounds antenna transmitters 914 and 916. For example, waveguide 1106 includes sidewall 1110 surrounding an outer sidewall of conductive ring 1008. The dimensions (e.g., width, length) of waveguide 1106 can be configured to propagate signals with a desired wavelength (e.g., radar, millimeter-wave signals, 30 GHz to 300 GHz).

[0038] Figure 12 A plan view is shown in the embodiment. Figure 11 An example semiconductor device 300 with a waveguide is depicted during a manufacturing stage. In this manufacturing stage, the semiconductor device 300 includes a component (1000) attached to a common substrate (1104) and an overlapping waveguide structure 1102. The semiconductor die 902 below is shown in dashed outline, labeled 902, for reference. Figures 9 to 11 The illustrated example manufacturing stage shows a cross-sectional view of a semiconductor device 300 including waveguide 1106, taken along line CC. Waveguide 1106 is formed as a waveguide opening in waveguide structure 1102, through which conductive ring 1008 and encapsulation 928 above antenna transmitters (914 and 916) are exposed.

[0039] Figure 13 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 16An example component of an example semiconductor device 400 with a waveguide is described. During this manufacturing stage, the component of the semiconductor device 400 includes an encapsulation (e.g., epoxy material) 1328 that encapsulates a semiconductor die 1302 and emitter structures 1306 and 1308 placed on a carrier substrate 1304. In this embodiment, the semiconductor die 1302 and emitter structures 1306 and 1308 are overmolded with an epoxy material encapsulation.

[0040] In this embodiment, transmitter structures 1306 and 1308 are formed as laminated structures having antenna transmitters 1314 and 1316 located on the top surfaces of transmitter structures 1306 and 1308, respectively. For example, transmitter structure 1306 includes conductive interconnects 1318 and 1320 (e.g., metal or other conductive material) separated by a non-conductive material 1312 (e.g., FR-4, ceramic). Conductive interconnect 1318 provides a conductive connection between an end pad 1322 and a conductive ball connector 1326 (e.g., solder ball) on the bottom surface of transmitter structure 1306. Antenna transmitter 1314 is connected to end pad 1324 on the bottom surface of transmitter structure 1306 via conductive interconnect 1320. Conductive interconnect 1318 and conductive ball connector 1326 are configured and arranged to substantially surround antenna transmitter 1314 and conductive interconnect 1320.

[0041] Semiconductor die 1302 has an active surface (e.g., a main surface having a circuit system) and a back-side surface (e.g., a main surface opposite the active surface). Semiconductor die 1302 includes bonding pads 1310 located on the active surface, the bonding pads 1310 being configured, for example, to be connected to antenna transmitters 1314 and 1316 via RDL. Semiconductor die 1302 can be formed from any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium nitride, etc. Semiconductor die 1302 can additionally include any digital circuitry, analog circuitry, RF circuitry, memory, signal processor, MEMS, sensor, etc., and combinations thereof.

[0042] Figure 14 A simplified cross-sectional view is shown of an example component in a subsequent manufacturing stage according to an embodiment. In this manufacturing stage, component 1400 includes an encapsulation 1328 that at least partially encapsulates semiconductor die 1302 and emitter structures 1306 and 1308, as well as an RDL substrate 1404 and a ball connector 1418.

[0043] In this embodiment, a back-side grinding operation is performed on component 1400 to expose portions of the ball connector 1326 of transmitter structures 1306 and 1308 and the back-side surface of semiconductor die 1302. A conductive ring 1408 is formed as a conductive layer (e.g., metal or other conductive material) on the sidewall of an opening in a non-conductive substrate 1410. The conductive ring 1408 is attached to the exposed portions of the ball connector 1326 via a conductive connector 1406 (e.g., solder, conductive adhesive, anisotropic conductive film). The conductive ring 1408 is configured and arranged to act as a conductive wall or fence that substantially surrounds antenna transmitter 1314 and forms cavity 1412. Similarly, the conductive ring substantially surrounds antenna transmitter 1316 and forms cavity 1414. In some embodiments, it may be necessary to connect the conductive wall or fence to a ground power supply or other power supply.

[0044] After removing the carrier substrate 1304, an RDL substrate 1404 is applied to the resulting exposed bottom surfaces, which include the exposed active surfaces of the semiconductor die 1302 and the exposed bottom surfaces of the transmitter structures 1306 and 1308. A conductive feed 1416 is formed in the RDL substrate 1404 between the bonding pad 1310 and the end pad 1324 to interconnect the semiconductor die 1302 with the antenna transmitters 1314 and 1316, respectively. After applying the RDL substrate 1404, a conductive ball connector 1418 (e.g., a solder ball) is attached to the bottom surface of the RDL substrate 1404. For example, the ball connector 1418 is configured and arranged to provide a conductive connection between the assembly 1400 and the printed circuit board (PCB). The ball connector 1418 can be any suitable conductive structure, such as a solder ball, gold stud, copper pillar, etc., to connect the conductive parts of the assembly 1400 to the PCB. In this embodiment, the RDL substrate 1404 is formed as an add-on substrate including a redistribution layer. In some embodiments, the RDL substrate 1404 may be formed as a preformed substrate including a redistribution layer. In other embodiments, the ball connector 1418 may be directly attached to the end pads 1322, 1324 and the bonding pad 1310 for, for example, connection to a PCB without using the RDL substrate.

[0045] Figure 15 A simplified cross-sectional view illustrates the process along the manufacturing stage according to an embodiment. Figure 16An example semiconductor device 400 with a waveguide is described. In this manufacturing stage, the semiconductor device 400 with a waveguide includes a component 1400 attached to a common substrate 1504 and an overlapping waveguide structure 1502. With the component 1400 and the overlapping waveguide structure 1502 attached to the substrate 1504, the waveguide structure 1502 is physically separated from the component 1400. For example, the waveguide structure 1502 does not physically contact the component 1400. In this embodiment, the substrate 1504 may be located on a PCB or, for example, on another multilayer substrate configured to connect to other components of the system.

[0046] Waveguide structure 1502 includes waveguide 1506 (e.g., waveguide opening) and is attached to substrate 1504 at interface 1508. For example, waveguide structure 1502 can be attached to substrate 1504 at interface 1508 using screws, alignment pins, adhesives, and combinations thereof. In this embodiment, waveguide structure 1502 is formed of a conductive material such as a metal (e.g., aluminum, copper), other conductive materials, or combinations thereof. Waveguide 1506 is formed as a waveguide opening in waveguide structure 1502, through which the surface of encapsulation 1328 above antenna transmitters 1314 and 1316 is exposed. In this embodiment, waveguide opening 1506 includes sidewall portions 1510 extending downward into cavities 1412 and 1414 and substantially surrounding antenna transmitters 1314 and 1316, respectively. The dimensions (e.g., width, length) of waveguide 1506 can be configured to propagate signals with a desired wavelength (e.g., radar, millimeter-wave signals, 30 GHz to 300 GHz).

[0047] Figure 16 A plan view is shown in the embodiment. Figure 15 The image depicts an example semiconductor device 400 with a waveguide during a manufacturing stage. In this manufacturing stage, the semiconductor device 400 with a waveguide includes a component (1400) attached to a common substrate (1404) and an overlapping waveguide structure 1502. The semiconductor die 1302 below is shown in a dashed outline, labeled 1302, for reference. Figures 13 to 15 The illustrated example manufacturing stage shows a cross-sectional view of a semiconductor device 400 with a waveguide, including a waveguide 1506, taken along line DD. The waveguide 1506 is formed as a waveguide opening in a waveguide structure 1502, through which the encapsulation 1328 above the antenna transmitters (1314 and 1316) is exposed.

[0048] Generally, a method of manufacturing a semiconductor device is provided, the method comprising: forming an assembly, including: placing a semiconductor die and a transmitter structure on a carrier substrate, the transmitter structure including an antenna transmitter; encapsulating at least a portion of the semiconductor die and the transmitter structure; applying a redistribution layer on a first main surface of the semiconductor die and a first main surface of the transmitter structure, the bonding pads of the semiconductor die being connected to the antenna transmitter through the redistribution layer; attaching the assembly to the substrate; and attaching a waveguide structure to the substrate, the waveguide structure overlapping with and physically separated from the assembly. The transmitter structure may be formed having a cavity, the antenna transmitter being located on the bottom surface of the cavity. Attaching the waveguide structure to the substrate may further include extending sidewalls of openings in the waveguide structure into the cavity to substantially surround the antenna transmitter. The size of the openings in the waveguide structure may be configured for propagating millimeter-wave signals. The method further includes forming a conductive ring structure substantially surrounding the antenna transmitter, the outer sidewalls of the conductive ring structure being spaced apart from the sidewalls of the cavity to form a channel between the conductive ring structure and the sidewalls of the cavity. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure into a channel formed between the conductive ring structure and the sidewalls of the cavity. The method may further include back-side grinding of the assembly to expose conductive paths that substantially surround the antenna transmitter; and attaching the conductive ring structure to the exposed conductive paths. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure to substantially surround the conductive ring structure. Attaching the waveguide structure to the substrate may further include extending the sidewalls of the opening in the waveguide structure to substantially surround the antenna transmitter, with the conductive ring structure surrounding the extended sidewalls of the opening.

[0049] In another embodiment, a semiconductor device is provided, the semiconductor device comprising: a printed circuit board (PCB) having a top-side surface; a package assembly attached to the PCB at the top-side surface, the package assembly including a package substrate having a first main surface and a second main surface; a semiconductor die having an active surface and a back-side surface, the semiconductor die being attached to the package substrate at the first main surface; a transmitter structure attached to the package substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die through the package substrate; and an epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and a waveguide structure attached to the PCB at the top-side surface, the waveguide structure overlapping with and physically separated from the package assembly. The package substrate may be characterized as an add-on substrate including a redistribution layer configured to couple bonding pads on the active surface of the semiconductor die to the antenna transmitter. The waveguide structure may be configured and arranged for propagating millimeter-wave signals. The transmitter structure may be formed having a cavity, with the antenna transmitter located on the bottom surface of the cavity. The waveguide structure may include a waveguide opening having a sidewall portion extending into the cavity and substantially surrounding the antenna transmitter. The transmitter structure may additionally include a conductive ring structure substantially surrounding the antenna transmitter, the outer wall of the conductive ring structure being spaced apart from the sidewall of the cavity to form a channel between the conductive ring structure and the sidewall of the cavity. The waveguide structure may include a waveguide opening having a sidewall portion extending into the channel formed between the conductive ring structure and the sidewall of the cavity.

[0050] In another embodiment, a semiconductor device is provided, the semiconductor device including a printed circuit board (PCB) having a top side surface; a packaged semiconductor device attached to the PCB at the top side surface, the packaged semiconductor device including a packaged substrate having a first main surface and a second main surface; a semiconductor die having an active surface and a back side surface, the semiconductor die being attached to the packaged substrate at the first main surface; a transmitter structure attached to the packaged substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die through a conductive feed of the packaged substrate; and an epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and a waveguide structure attached to the PCB at the top side surface, the waveguide structure overlapping the packaged semiconductor device, waveguide openings of the waveguide structure having sidewalls substantially surrounding the antenna transmitter, the waveguide structure being physically separated from the packaged semiconductor device. The transmitter structure may be formed having a cavity, with the antenna transmitter located on the bottom surface of the cavity. Sidewall portions of the waveguide openings may extend into the cavity and substantially surround the antenna transmitter. The transmitter structure may additionally include a conductive ring structure that substantially surrounds the antenna transmitter and is spaced apart from the sidewalls of the cavity to form a channel between the conductive ring structure and the sidewalls of the cavity, with the sidewall portion of the waveguide opening extending into the channel formed between the conductive ring structure and the sidewalls of the cavity.

[0051] To date, it should be understood that a semiconductor device including a packaged assembly has been provided, the packaged assembly being attached to a common substrate together with an overlapping waveguide structure. The waveguide structure is physically separated from the packaged assembly. A semiconductor die and a transmitter structure are encapsulated on the packaged substrate to form the packaged assembly. The waveguide structure includes a waveguide opening above the antenna transmitter of the transmitter structure, thereby allowing the propagation of radio frequency (RF) signals. By physically separating the overlapping waveguide structure from the packaged assembly, package stress can be reduced and reliability improved, while low-loss RF signal performance is achieved within a compact footprint.

[0052] The terms “front,” “back,” “top,” “bottom,” “above,” “under,” etc. (if applicable) used in this specification and claims are for descriptive purposes and are not necessarily used to describe permanent relative positions. It should be understood that such terms are interchangeable where appropriate, such that embodiments of the invention described herein can be operated, for example, in orientations other than those shown or otherwise described herein.

[0053] While the invention has been described herein with reference to specific embodiments, various modifications and changes may be made without departing from the scope of the invention as set forth in the appended claims. Therefore, the specification and drawings should be considered illustrative rather than restrictive, and all such modifications are contemplated to be included within the scope of the invention. It is not intended that any advantage, benefit, or solution to the problem described herein with reference to specific embodiments be construed as a critical, necessary, or essential feature or element of any or all claims.

[0054] Furthermore, as used herein, the term "a" is defined as one or more. Moreover, the use of introductory phrases such as "at least one" and "one or more" in the claims should not be construed as implying that another claim element introduced by the indefinite article "a(a)" or "an" limits any particular claim containing such introduced claim element to an invention containing only one such element, even when the same claim includes the introductory phrase "one or more" or "at least one" and indefinite articles such as "a(a)" or "an". The same applies to the use of definite articles.

[0055] Unless otherwise stated, terms such as “first” and “second” are used to distinguish, arbitrarily, the elements described by such terms. Therefore, these terms are not necessarily intended to indicate the temporal or other priority of such elements.

Claims

1. A method for manufacturing a semiconductor device, characterized in that, The method includes: Forming components, including: A semiconductor die and transmitter structure are placed on a carrier substrate, wherein the transmitter structure includes an antenna transmitter; Encapsulating at least a portion of the semiconductor die and the transmitter structure; Remove the carrier substrate to expose the first main surface of the semiconductor die and the first main surface of the emitter structure; After removing the carrier substrate, a redistribution layer is applied to the first main surface of the semiconductor die and the first main surface of the transmitter structure, and the bonding pads of the semiconductor die are connected to the antenna transmitter through the redistribution layer; Attach the component to the substrate; A waveguide structure is attached to the substrate, the waveguide structure overlapping with the component and physically separated from the component; The transmitter structure is formed with a cavity, and the antenna transmitter is located on the bottom surface of the cavity; and Attaching the waveguide structure to the substrate also includes extending the sidewalls of the openings in the waveguide structure into the cavity to surround the antenna transmitter.

2. The method according to claim 1, characterized in that, Additionally, it includes forming a conductive ring structure that substantially surrounds the antenna transmitter, the outer wall of the conductive ring structure being spaced apart from the sidewall of the cavity to form a channel between the conductive ring structure and the sidewall of the cavity.

3. The method according to claim 1, characterized in that, In addition, including: The component is back-side ground to expose the conductive paths that substantially surround the antenna transmitter; as well as Attach the conductive ring structure to the exposed conductive path.

4. A semiconductor device, characterized in that, include: A printed circuit board (PCB) having a top side surface; The package assembly is attached to the PCB at the top side surface, the package assembly comprising: An encapsulation substrate having a first main surface and a second main surface; A semiconductor die having an active surface and a back surface, the semiconductor die being attached to the packaging substrate at the first main surface; A transmitter structure attached to the packaging substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die through the packaging substrate; and An epoxy material, said epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and A waveguide structure is attached to the PCB at the top side surface, the waveguide structure overlaps with the package assembly and is physically separated from the package assembly; The transmitter structure is formed with a cavity, and the antenna transmitter is located on the bottom surface of the cavity; and The waveguide structure includes a waveguide opening having a sidewall portion that extends into the cavity and surrounds the antenna transmitter.

5. The semiconductor device according to claim 4, characterized in that, The transmitter structure further includes a conductive ring structure that substantially surrounds the antenna transmitter, the outer sidewall of the conductive ring structure being spaced apart from the sidewall of the cavity to form a channel between the conductive ring structure and the sidewall of the cavity.

6. A semiconductor device, characterized in that, include: A printed circuit board (PCB) having a top side surface; A packaged semiconductor device, the packaged semiconductor device being attached to the PCB at the top side surface, the packaged semiconductor device comprising: An encapsulation substrate having a first main surface and a second main surface; A semiconductor die having an active surface and a back surface, the semiconductor die being attached to the packaging substrate at the first main surface; A transmitter structure attached to the packaging substrate at the first main surface, the transmitter structure including an antenna transmitter coupled to the semiconductor die via a conductive feed through the packaging substrate; and An epoxy material, said epoxy material encapsulating at least a portion of the semiconductor die and the transmitter structure; and A waveguide structure is attached to the PCB at the top side surface, the waveguide structure overlaps with the packaged semiconductor device, the waveguide opening of the waveguide structure has sidewalls surrounding the antenna transmitter, and the waveguide structure is physically separated from the packaged semiconductor device. The transmitter structure is formed with a cavity, and the antenna transmitter is located on the bottom surface of the cavity; and The sidewall portion of the waveguide opening extends into the cavity and surrounds the antenna transmitter.

7. The semiconductor device according to claim 6, characterized in that, The transmitter structure further includes a conductive ring structure that substantially surrounds the antenna transmitter and is spaced apart from the sidewalls of the cavity to form a channel between the conductive ring structure and the sidewalls of the cavity, wherein a portion of the sidewall of the waveguide opening extends into the channel formed between the conductive ring structure and the sidewalls of the cavity.

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