Open cavity integrated circuit

Abstract

An electronic device (100) includes a substrate (102) and a die (104) having an active surface disposed on the substrate (102). A sensor (108) is in communication with the active surface of the die (104). A ring (106) surrounds the sensor (108) and includes a cylindrical wall (126) and a cover (128), wherein the cover (128) has a partially circular shape extending beyond each side of the wall (126). A molding compound (112) covers the die (104) and abuts an outer surface of the wall (126), thereby forming a cavity (134) in the molding compound (112) to expose the sensor (108) to an environment external to the electronic device (100).

Description

Technical Field

[0001] The present disclosure relates to an electronic device, and more particularly to an open cavity integrated circuit package that includes a mushroom-shaped capping plating wall in a cavity. Background Art

[0002] Open cavity packages (OCPs) are used as sensor packages to measure various physical properties of the environment, such as humidity, temperature, optical properties, sound, pressure, adverse environmental conditions, etc. Thus, an OCP includes sensors that sense physical properties and other circuitry that processes the sensed physical properties. Therefore, the sensors must be exposed to the environment, while the other circuitry must be protected from the environment to avoid damaging the circuitry. Thus, an OCP is manufactured such that the sensors are exposed to the environment, but the other circuitry is covered and protected by a molding compound. Thus, an OCP includes a cavity that extends through the molding compound down to the surface of the die. The sensors are disposed on the surface of the die in the cavity and are thus directly exposed to the environment to be tested. It is necessary that the molding compound does not enter the cavity during the molding process. Summary of the Invention

[0003] In the described example, an electronic device includes a substrate and a die having an active surface disposed on the substrate. A sensor communicates with the active surface of the die. A ring surrounds the sensor and includes a cylindrical wall and a cap, where the cap has a partial circular shape that extends beyond each side of the wall. A molding compound covers the die and abuts an outer surface of the wall, thereby forming a cavity in the molding compound to expose the sensor to the environment external to the electronic device.

[0004] In another described example, a method includes: providing a die that includes a sensor; and depositing a ring on the die, where the die surrounds the sensor. The die is placed on a substrate, and both the die and the substrate are placed in a mold cavity that includes a film assist material. The mold cavity holds the die and the substrate such that the film assist material layer contacts the cap of the ring. A molding compound is injected into the mold cavity and abuts an outer surface of the ring. The ring and the film assist material layer prevent the molding compound from entering the interior of the ring.

[0005] In yet another described example, an electronic device includes a fabricated die assembly that includes a die providing an active surface, where the die includes a sensor. A stress relief layer is deposited on the active surface of the die, and a seed layer is deposited on the stress relief layer. A layer of photoresist material is deposited over the die and patterned to form an annular opening in the seed layer. Metal is electroplated on the seed layer within the annular opening to form a metal ring. The sensor is placed on the active surface of the die inside the metal ring, and the die assembly is placed on a substrate. The die assembly and the substrate are placed in a mold cavity that includes a film assist material. The mold cavity holds the die assembly and the substrate such that the film assist material layer contacts a lid of the metal ring. A molding compound is injected into the mold cavity and abuts an outer surface of the metal ring. The metal ring and the film assist material prevent the molding compound from entering the interior of the metal ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a cross-sectional view of an example electronic device.

[0007] Figure 2 is a top view of a wafer including dies.

[0008] Figure 3 shows a cross-sectional view of a singulated die from the wafer in Figure 2 during an early stage of fabricating the die assembly.

[0009] Figure 4 shows Figure 3 a cross-sectional view of a singulated die including a sensor integrated into the die in

[0010] Figure 5 shows Figure 4 a cross-sectional view of a die assembly including an optional die polymer layer in

[0011] Figure 6 shows Figure 5 a cross-sectional view of the die assembly in

[0012] Figure 7 showing Figure 6 the die assembly in

[0013] Figure 8 showing Figure 7 a side view of the die assembly in

[0014] Figure 9 showing Figure 8 a side view of the die assembly in

[0015] Figure 10A and10B for Figure 9 A close-up cross-sectional view of the electroplating process in Figure 1.

[0016] Figure 11 Show Figure 9 A cross-sectional view of a die assembly after undergoing an etching process to strip off the photoresist material layer and partially etch the seed layer.

[0017] Figure 12 A cross-sectional view of a leadframe based substrate is shown in an early stage of assembling an electronic device.

[0018] Figure 13 Show Figure 12 Cross-sectional view of an electronic device undergoing deposition of die attach material.

[0019] Figure 14 Show Figure 11 A cross-sectional view of an electronic device having a die assembly attached to a lead frame.

[0020] Figure 15 Show Figure 14 A cross-sectional view of an electronic device undergoing a wire bonding process.

[0021] Figure 16 Show Figure 15 A cross-sectional view of an electronic device being placed in a mold slot.

[0022] Figure 17 Show Figure 16 Cross-sectional view of an electronic device undergoing vacuum in a mold cavity.

[0023] Figure 18 Show Figure 17 A cross-sectional view of an electronic device after undergoing injection molding compound to deposit interconnects.

[0024] Figure 19 Show Figure 18 A cross-sectional view of an electronic device after removal of the electronic device from a mold slot.

[0025] Figure 20 Show Figure 1 and 19 A cross-sectional view of a variation of an electronic device that does not include the optional die polymer layer.

[0026] Figure 21 Show Figure 1 and 19 Cross-sectional view of a variation of an electronic device that does not include the optional polymer or metal layer.

[0027] Figure 22 Show Figure 1 and19 Cross-sectional view of a variant of an electronic device without an optional plated metal layer.

[0028] Figure 23 Shows Figure 1 and 19 Cross-sectional view of a variant of an electronic device without an optional die polymer layer and an optional polymer or metal layer.

[0029] Figure 24 Shows Figure 1 and 19 Cross-sectional view of a variant of an electronic device without an optional die polymer layer and an optional plated metal structure.

[0030] Figure 25 Shows Figure 1 and 19 Cross-sectional view of a variant of an electronic device without an optional polymer or metal layer and an optional plated metal structure.

[0031] Figure 26 Shows Figure 1 and 19 Cross-sectional view of a variant of an electronic device without an optional die polymer layer, an optional polymer or metal layer, and an optional plated metal structure. Detailed Description

[0032] An open cavity package (OCP) integrated circuit serves as a sensor package for measuring various physical properties of an environment, such as humidity, temperature, optical properties, sound, pressure, adverse environmental conditions, etc. Thus, the OCP includes sensors disposed in the cavity of the OCP to sense the corresponding physical properties and other circuitry for processing the sensed physical properties. Accordingly, the sensors are exposed to the environment, while the other circuitry must be protected from the environment to avoid damaging the circuitry.

[0033] Current manufacturing processes involve complex and expensive molding equipment that is limited in its ability to produce smaller packages with smaller sensor cavities in the OCP while preventing any molding compound from entering the cavity. Additionally, the complex and expensive molding equipment used to create the sensor cavity is package-specific, meaning that the equipment is generally not reusable for multiple types of OCPs. Instead, different equipment is required for different types of OCPs. The investment in different types of equipment results in a significant increase in design costs, manufacturing costs, lead times, and production times.

[0034] An electronic device is described herein, and more particularly an open cavity package (OCP) integrated circuit and a method of fabricating an OCP that overcomes the challenges described above. The OCP includes a ring having a cylindrical wall (e.g., a plated metal ring) and a partially circular or semi-circular lid. Thus, a cross-sectional view of the ring and the lid substantially has a mushroom shape. The ring is positioned on a die, and a sensor is disposed on the die inside the ring. During a molding process, the OCP is placed in a mold cavity. A film is disposed between the ring and the mold cavity. When the mold cavity clamps the OCP, the film contacts the lid portion of the ring and prevents molding compound from flowing inside the ring and onto the sensor. Thus, a cavity is formed in the molding compound in which the sensor resides. The ring can be made of a metal or non-metal material, and it can be grown on a semiconductor die using a plating process or a printing process using an ink containing a metal or non-metal material, or it can be fabricated separately from the semiconductor die and coupled to the semiconductor die using an adhesive.

[0035] Figure 1 FIG. 4 is a cross-sectional view of an example electronic device 100 (e.g., an open cavity package (OCP)) that includes a substrate 102, a die 104 disposed on the substrate 102, a ring 106 disposed on the die 104, a sensor 108 disposed on the die 104 and inside the ring 106, wire bondings 110, and a molding compound 112. The electronic device 100 can include an integrated circuit (IC) and more particularly an open cavity package (OCP) including but not limited to quad flat no-lead (QFN) packages, quad flat packages (QFP), ball grid array (BGA) packages, etc. Although Figure 1 the example electronic device 100 shown depicts one ring 106 disposed on the die 104, the die having a sensor 108 disposed inside the ring 106, in other examples, the electronic device 100 can include multiple sensors, where multiple rings are disposed on the die and sensors are disposed in each ring. Thus, Figure 1 the electronic device shown is for illustrative purposes only and does not limit the scope of the present invention.

[0036] The substrate 102 includes a lead frame that includes die pads 114 and conductive terminals 116 (e.g., leads, contacts). In alternative examples, the substrate can include a laminated substrate or a printed circuit board-based substrate. For illustrative purposes only, a lead frame-based substrate will be described herein and shown in the figures. The die pads 114 can include thermal pads that are exposed on the attachment side 118 of the electronic device 100. The thermal pads create an effective thermal path from the electronic device 100 to a board (e.g., a printed circuit board). Additionally, the exposed thermal or die pads 114 also enable a ground connection to the board.

[0037] Die 104 is attached to die pad 114 via die attach material 120. In one example, die 104 may optionally include a die polymer layer (e.g., polyimide) 122 disposed on the active (wire bond) surface 124 of die 104. Die polymer layer 122 reduces stress between die 104 and ring 106 (stress relief layer). In some applications such as humidity sensing, die polymer layer 122 may also enhance the sensing function and characteristics of the die and sensor 108.

[0038] Ring 106 is formed on die 104 via a plating process as described below and includes a cylindrical wall 126 and a cap 128. Ring 106 may be formed of a metal such as, but not limited to, copper, aluminum, nickel, iron, etc. Cap 128 has a partially circular or semi-circular shape and extends beyond each side of wall 126. Thus, a cross-sectional view of ring 106 has a mushroom shape as Figure 1 shown. In one example, ring 106 may be formed directly on die 104, or in another example, ring 106 may be formed on optional die polymer layer 122. The size of ring 106 is specific to the sensing application. For example, ring 106 may have a height (e.g., 70um to 160um) such that the top of cap 128 extends above the maximum height H of wire bond 110 and may be limited only by the wire bonding ability to produce a low profile wire bond. Ring 106 may have an inner diameter equal to or greater than the sensor area of die 104 (e.g., 100um to 500um) to prevent affecting sensor performance.

[0039] In addition, one or more layers may optionally be disposed between ring 106 and die 104 to reduce stress between ring 106 and die 104 (stress relief layer) and / or for enhancing the sensing characteristics of electronic device 100. For example, a plated metal structure 130 having a thickness range of 3um to 10um may be deposited directly on die 104, or in another example, on die polymer layer 122 before depositing ring 106. Additionally, a polymer or metal layer 132 may be deposited directly on die 104, or in another example, on die polymer layer 122 before depositing ring 106 or plated metal structure 130 if a seed layer is required. Thus, different combinations of polymer and metal stacks may be used for stress relief and / or enhancing the sensing characteristics of electronic device 100. Polymer layer 132 may include non-photodefinable or photodefinable chemicals having positive or negative photoactivity. Combinations of photoactive, non-photoactive, resist polymers, and electroplated copper structures may be used to achieve the desired dimensions and functionality required for applications in stress relief and / or performance enhancement in sensing.

[0040] The sensor 108 communicates with the active surface 124 of the die 104 and is disposed inside the ring 106. Thus, the ring 106 surrounds the sensor 108. In one instance, at the wafer level, the sensor 108 is integrated into the active surface 124 of the die 104 such that the top surface of the sensor 108 is substantially flush with the active surface 124 of the die 104. In another instance, the sensor 108 may be partially integrated into the active surface 124 of the die 104 such that the sensor 108 extends partially above the active surface 124 of the die 104. In yet another instance, the sensor 108 may be disposed over the active surface 124 of the die 104 such that the sensor 108 is completely above the die 104. The sensor 108 may be configured to sense any of a variety of physical properties, such as humidity, light, sound, pressure, bulk acoustic wave, stress, temperature, current, voltage, power, motion, acceleration, magnetic field, and other physical properties. The active surface 124 of the die 104 may include other circuitry coupled to the sensor 108, the sensor being configured to receive and process signals from the sensor 108 in a suitable manner. For example, a sensing element (not shown in the figures) that interrogates the sensor 108 to generate a signal may be disposed below the sensor 108, across or partially around the sensor 108, or sandwiched above and below the sensor 108 in the form of an interdigital lateral comb pattern. The interrogation signal may be in the form of a frequency, current, resistance, capacitance, etc. The wire bond 110 provides a connection between the active or wire bond surface 124 of the die 104 and the conductive terminal 116.

[0041] The molding compound 112 covers all but one of the surfaces of the lead frame 102, with the non-covered surface facing away from the electronic device 100. Additionally, the molding compound 112 encapsulates the wire bond 110 and covers portions of the die 104. As described below, the molding compound 112 abuts the outer surface of the ring 106 and thus prevents entry into the interior of the ring 106 and thus does not cover the sensor 108. Thus, a cavity 134 is formed in the molding compound 112, thereby forming the open cavity electronic device 100.

[0042] Figures 2 to 19 Shown in connection with Figure 1 a manufacturing process associated with the formation of the electronic device (e.g., OCP) 100 shown. Although depicted sequentially for convenience, at least some of the actions shown may be performed in a different order and / or in parallel. Alternatively, some embodiments may perform only some of the actions shown. Furthermore, although Figures 2 to 19 the example shown is an example method of an example configuration shown Figure 1 , other methods and configurations are also possible. Although Figures 2 to 19The method shown depicts the manufacturing process of a single open cavity electronic device, but the process is applicable to an OCP array. Thus, after manufacturing the OCP array, the array is singulated to separate the OCPs from the array.

[0043] Figures 2 to 11 shows the manufacturing process associated with the formation of the die of the electronic device 100 shown in Figure 1 Specifically, referring to Figure 2 , in various examples, Figure 2 is a schematic diagram of a wafer 200. For example, the wafer 200 can be a silicon wafer. The wafer 200 includes a plurality of dies 202. The manufacturing techniques described below can be performed on individual dies 202 (post-singulation), or the techniques can be performed more efficiently on a mass scale, such as simultaneously on multiple dies 202 of the wafer 200 (pre-singulation). For convenience and clarity, although the remaining figures show one die 202, it should be understood that the processes described herein as being performed on die 202 can also be performed on the remaining dies 202 of the wafer 200 (e.g., sequentially, simultaneously).

[0044] Figure 3 shows a cross-sectional view of a single die 202 singulated from the wafer 200. A sensor 204 is integrated into the active (wire bond) surface 206 of the die 202 such that the top surface of the sensor 204 is substantially flush with the active surface 206 of the die 202, thereby creating the Figure 4 configuration. However, as described, the sensor 204 can be partially integrated into the active surface 206 of the die 202 or can be disposed on the active surface 206 of the die 202. For example, in an application where the sensor 204 is configured to sense humidity, the sensor 204 is integrated into the die 202 as a lateral capacitor. The lateral capacitor uses a transducer dielectric (e.g., polyimide) on top as a functional material, which will change its dielectric constant as the humidity level changes, thereby causing a change in capacitance.

[0045] An optional die polymer layer 208 (e.g., polyimide) is deposited on the active surface 206 of the die 202, thereby creating the Figure 5 configuration in Figure 5 The configuration in Figure 6 undergoes a first deposition process 300 to deposit and pattern an optional stress relief polymer layer 210 on the die 202 or on the optional die polymer layer 208, thereby creating the Figure 6 configuration in Figure 7Configurations in. Those skilled in the art in the field of electroplated layers on wafers will recognize that a conductive seed layer must be deposited to blanket the wafer, thereby effectively creating a conductive surface to initiate the electrochemical deposition of metal. Once the structure of interest has been electroplated, this seed layer will be etched away. Although only the main metal structures are shown in each figure for simplicity, they are plated using a seed metal (such as but not limited to Ti, TiW, TiW + Cu).

[0046] Reference Figure 8 , a photoresist material layer 214 is disposed over the die 202 and patterned and developed to expose an annular opening 216 that is consistent with the pattern in the photoresist material layer 214. The photoresist material layer 214 can have a thickness that varies corresponding to the radiation wavelength used to pattern the photoresist material layer 214. The photoresist material layer 214 can be formed over the die 202 via spin coating or spin casting deposition techniques, selectively irradiated (e.g., via deep ultraviolet (DUV) irradiation), and developed to form the annular opening 216.

[0047] Figure 8 The configurations in undergo an electroplating process 320 to deposit a metal plating (e.g., copper) 218 in the annular opening 216, thereby creating Figure 9 the configurations in. Figure 10A and 10B show a close-up cross-sectional view of the plating process when the metal plating fills 218 the annular opening 216 in the photoresist material layer 214. Reference Figure 10A , when the metal plating 218 is plated within the walls of the photoresist material layer 214, the metal plating 218 is plated in the vertical direction as indicated by the arrow. Once the metal plating 218 reaches the top surface of the photoresist material layer 214, the metal plating 218 continues to be plated in the vertical direction as indicated by the arrow. However, the metal plating 218 is also plated in the horizontal direction as indicated by the double-headed arrow, see Figure 10B . Thus, once the metal plating 218 reaches the top of the photoresist material layer 214, the metal plating 218 is plated vertically and horizontally on the surface of the photoresist material layer 214.

[0048] The metal plating 218 forms a ring 220 on the die 202, and the ring includes a cylindrical wall 222 and a cap 224. The cap 224 has a partially circular or semi-circular shape and extends beyond each side of the cylindrical wall 222. Thus, the cross-sectional view of the ring 220 has as Figure 9 and 10BThe mushroom shape shown. Additionally, a secondary plating option can be utilized prior to stripping the photoresist to help passivate the metal structure. Plating finishes such as OSP, matte Sn, SnAg, electroless Sn, electroless Ag, Ni, NiPd, NiAu, NiPdAu, and electroless NiAu (ENiG), etc. are well-known techniques familiar to those in the electronics assembly art.

[0049] Once the plating process 320 is complete, the photoresist material layer 214 is removed via a solvent stripping process 330. Additionally, during the etching process, portions of the blanket of the metal structure 212 covering the entire wafer (not shown for simplicity) are etched such that the metal structure 212 extending beyond the cylindrical wall 222 of the ring 220 remains intact, thereby creating Figure 11 the configuration in. The metal structure 212 distributes the weight of the ring 220, thereby diffusing the stress from the ring 220 to prevent cracking in the polymer layer 10. Figure 11 The configuration in represents a single die assembly 226 that includes a die 202 and a sensor 204 disposed inside the ring 220.

[0050] Figures 12 to 19 illustrates the manufacturing process associated with the process of placing the die assembly 226 on a substrate and the resulting Figure 1 molding process of the electronic device 100 shown. In the following description, the substrate includes a lead frame. In alternative examples, the substrate may include a laminated substrate or a printed circuit board-based substrate. For illustrative purposes only, a lead frame-based substrate will be described herein and shown in the figures.

[0051] Figure 12 shows a cross-sectional view of a lead frame 230 that includes die pads 232 and conductive terminals 234 (e.g., leads, contacts). A die attach material 236 is deposited on the surface of the die pads 232, thereby creating Figure 13 the configuration in. For simplicity, a dispensed die attach technique is referenced; however, other die attach techniques can also be utilized, such as using a die attach film pre-applied to the backside of the wafer. The die assembly 226 is then picked up and placed on the die attach material 236, thereby creating Figure 14 the configuration in. Bonding wires 238 are attached from the active or bonding wire surface 208 of the die 202 to the surface of each of the conductive terminals 234, thereby creating Figure 15 the configuration in.

[0052] Refer to Figure 16 , Figure 15The configuration in is placed into a mold cavity, which includes a first (top) member 240 and a second (bottom) member 242. First and second film-assisted moldings (e.g., non-stick polymers, Teflon, etc.) 244, 246 are disposed in the mold cavity. Specifically, the first film-assisted molding 244 operates in conjunction with the first member 240, and the second film-assisted molding operates in conjunction with the second member 242. The first and second members 240, 242 of the mold cavity then clamp the electronic device 100, as Figure 16 shown. A vacuum is obtained between the top member 240 of the mold cavity and the first film-assisted molding 244 to hold the film in place. The bottom member 242 of the mold cavity and the second film-assisted molding 246 also use the same vacuum technique to hold the film in place. Once the mold tool is fully clamped, the first film-assisted molding 244 contacts the lid 224 of the ring 220 to provide a seal around the lid 224, as Figure 17 shown. Thus, the first film-assisted molding 244 seals the interior of the ring 220.

[0053] The molding compound 248 is injected into the mold cavity, as Figure 18 shown. The molding compound 248 covers all but one of the surfaces of the lead frame 230, with the one uncovered surface facing away from the electronic device 100. Additionally, the molding compound 248 encapsulates the wire bonds 238 and covers portions (both sides) of the die 202. However, the molding compound 248 abuts the outer surface of the ring 220 and is prevented from entering the interior of the ring 220 because the first film-assisted molding 244 contacts the lid 224 of the ring 220 and thus provides a seal around the lid. More specifically, the partially circular shape of the lid 224 has a larger surface area compared to a ring without a lid. Thus, there is more contact between the lid 224 and the film-assisted molding 244 to prevent the molding compound 248 from entering the interior of the ring 220. Thus, a cavity 250 in which the sensor 204 resides is formed in the molding compound 248, thereby exposing the sensor 204 to the environment designed to be sensed. Finally, the electronic device is removed from the mold cavity, resulting in Figure 19 the open cavity electronic device 252 shown.

[0054] Figures 20 to 26 Shown Figure 1 and 19 are variations of the electronic device shown. As described above, the die polymer layers 122, 208, the polymer or metal layers 132, 210, and the plated metal structures 130, 212 are optional layers. Thus, Figure 20 Shown Figure 1 and 19 is a cross-sectional view of a variation of the electronic device that does not include the optional die polymer layers 122, 208. Figure 21 Shown Figure 1 and 19Cross-sectional views of variants of electronic devices that do not include optional polymer or metal layers 132, 210. Figure 22 Shows Figure 1 And 19 Cross-sectional views of variants of electronic devices that do not include optional plated metal structures 130, 212. Figure 23 Shows Figure 1 And 19 Cross-sectional views of variants of electronic devices that do not include optional die polymer layers 122, 208 and optional polymer or metal layers 132, 210. Figure 24 Shows Figure 1 And 19 Cross-sectional views of variants of electronic devices that do not include optional die polymer layers 122, 208 and optional plated metal structures 130, 212. Figure 25 Shows Figure 1 And 19 Cross-sectional views of variants of electronic devices that do not include optional polymer or metal layers 132, 210 and optional plated metal structures 130, 212. Figure 26 Shows Figure 1 And 19 Cross-sectional views of variants of electronic devices that do not include optional die polymer layers 122, 208, optional polymer or metal layers 130, 212, and optional plated metal structures 130, 212.

[0055] Examples of the subject matter description are described above. Of course, it is not possible to describe every conceivable combination of components or methods for the purpose of describing the subject matter description, but one of ordinary skill in the art will recognize that many additional combinations and permutations of the subject matter description are possible. Accordingly, the subject matter description encompasses all such changes, modifications, and variations that fall within the spirit and scope of the appended claims. In addition, where the description or claims recite "a", "an", "first", or "another" element or the equivalent thereof, it should be construed to include one or more than one of such element, neither requiring nor precluding two or more of such elements. Further, insofar as the term "comprising" is used in the detailed description or claims, such term is inclusive in a manner similar to the term "including" as interpreted when used as a transitional word in a claim. Finally, the term "based on" is interpreted to mean at least partially based on.

Claims

1. An electronic device, include: substrate; a die having an active surface, the die being disposed on the substrate; a sensor in communication with the active surface of the die; a ring surrounding the sensor, the ring comprising a cylindrical wall and a cover having a partial circular shape extending beyond each side of the wall; A molding compound covers the die and abuts an outer surface of the wall, thereby forming a cavity in the molding compound to expose the sensor to an environment external to the electronic device. 2 . The electronic device of claim 1 , further comprising a metal structure disposed between the ring and the die.

3. The electronic device of claim 2, further comprising a stress relief layer disposed between the metal structure and the die. 4 . The electronic device of claim 1 , further comprising at least one stress relief layer and / or at least one metal structure disposed between the ring and the die. 5 . The electronic device of claim 1 , wherein an inner diameter of the ring is equal to or larger than a sensor area of ​​the die to prevent affecting sensor performance.

6. The electronic device of claim 1 further comprising wire bonds attached to the active surface of the die and to the substrate. 7 . The electronic device of claim 6 , wherein the ring has a height extending above a maximum height of the wire bonds.

8. The electronic device of claim 6, wherein the substrate is a lead frame, the lead frame comprising a die pad and conductive terminals, the die being attached to the die pad via a die attach material, and the wire bonds being attached to the conductive terminals.

9. A method wherein include: providing a bare die including the sensor; depositing a ring on the die, the die surrounding the sensor; placing the die on a substrate; placing the die and the substrate in a mold cavity, the mold cavity containing a film-assist material; The die is clamped by the mold groove, and the film auxiliary material contacts the cover of the ring; A molding compound is injected into the mold groove, the molding compound abuts against the outer surface of the ring, and the ring and the film-assist material prevent the molding compound from entering the interior of the ring.

10. The method of claim 9, wherein prior to placing the die and the substrate in a mold slot, the method further comprises attaching wire bonds from the die to the substrate.

11. The method of claim 9, wherein prior to depositing the ring on the die, the method further comprises depositing a die polymer layer on the die.

12. The method of claim 11, further comprising depositing a stress relief layer on the die polymer layer.

13. The method of claim 12, further comprising depositing a metal structure on the stress relief layer.

14. The method of claim 9, wherein depositing a ring on the die comprises electroplating metal within an annular opening in a layer of photoresist material in a vertical direction, and electroplating the metal on a surface of the layer of photoresist material in the vertical and horizontal directions when the metal exceeds a height of the layer of photoresist material.

15. The method of claim 14, wherein the metal plated in the annular opening forms a cylindrical wall of the ring, and the metal plated on the surface of the photoresist material layer forms a cover of the metal ring, the cover having a partial circular shape and extending beyond each side of the wall.

16. A method, wherein include: Manufacturing a die assembly, comprising: providing a die having an active surface, the die including a sensor; depositing a stress relief layer on the active surface of the die; depositing a metal structure on the stress relief layer; depositing a layer of photoresist material over the die, the photoresist material being patterned to form an annular opening over the metal structure; and electroplating metal in the annular opening on the metal structure to form a metal ring; placing the die assembly on a substrate; placing the die assembly and the substrate in a mold cavity, the mold cavity comprising a film-assist material; The die assembly and the substrate are clamped by the mold groove, and the film assist material contacts the cover of the metal ring; and A molding compound is injected into the mold groove, the molding compound abuts against an outer surface of the metal ring, and the metal ring and the film auxiliary material prevent the molding compound from entering an interior of the metal ring.

17. The method according to claim 16, wherein electroplating the metal on the metal structure in the annular opening includes electroplating the metal within the annular opening in a vertical direction, and when the metal exceeds the height of the photoresist material layer, electroplating the metal on the surface of the photoresist material layer in the vertical and horizontal directions.

18. The method of claim 17, wherein the metal plated in the annular opening forms a cylindrical wall of the metal ring, and the metal plated on the surface of the photoresist material layer forms a cover of the metal ring, the cover having a partial circular shape and extending beyond each side of the wall.

19. The method of claim 16, wherein the substrate is a lead frame, the lead frame comprising a die pad and a conductive terminal, wherein the die assembly is attached to the die pad via a die attach material, and wherein prior to placing the die assembly and the substrate in a mold slot, the method further comprises attaching wire bonds from the active surface of the die to the conductive terminal.

20. The method of claim 16, wherein prior to depositing a stress relief layer on the active surface of the die, the method further comprises depositing a die polymer layer on the active surface of the die.

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