Semiconductor package with built-in vibration isolation, thermal stability, and connector decoupling

Abstract

Semiconductor packages with design features including isolation structures for internal components and flexible electrical connections that minimize errors due to environmental temperature, shock, and vibration effects. The semiconductor package can include a base having a first portion surrounded by a second portion. A connector assembly can be attached to the first portion. The connector assembly can extend through an opening in the base. An attached lid can be attached to at least the second portion. The attached lid can form a hermetic chamber defined by an upper surface of the first portion, the connector assembly, and an inner surface of the lid. An elastomeric pad can be located on the first portion, and a subassembly can be located on the elastomeric pad. A flexible electrical connection can be formed between the connector assembly and the subassembly.

Description

[0001] Related applications

[0002] This application claims the benefit and priority of U.S. Patent Application No. 17 / 202,070, filed March 15, 2021, and U.S. Provisional Patent Application No. 63 / 045,368, filed June 29, 2020, the entire disclosures of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to microelectronic packaging and processes for packaging semiconductor devices, and more specifically, to packaging and methods for packaging microelectromechanical systems (MEMS) sensor modules. Background Technology

[0004] Microelectromechanical systems (MEMS) devices, such as inertial measurement units (IMUs), can include a variety of sensors, such as gyroscopes and accelerometers, which can be implemented in motion tracking systems. These sensors typically have microstructured sensing elements that need to be protected from various environmental influences during manufacturing and operation. For example, MEMS sensors designed to measure acceleration and rotational motion can be affected by various error sources such as external stresses, which can degrade motion measurement performance. Although various packaging schemes have been developed to encapsulate the sensing elements in MEMS devices, these schemes are often costly and not necessarily reliable. Summary of the Invention

[0005] A semiconductor package with design features including isolation structures for internal components that minimize errors caused by ambient temperature, shock, and vibration. The semiconductor package may include a base having a first portion surrounded by a second portion. A connector assembly may be attached to the first portion. The connector assembly may extend through an opening in the base. An attached cap may be attached to at least the second portion. The attached cap may form an hermetically sealed chamber defined by the upper surface of the first portion, the connector assembly, and the inner surface of the cap. An elastomeric pad may be located on the first portion, and a sub-assembly may be located on the elastomeric pad. A flexible electrical connection may be formed between the connector assembly and the sub-assembly.

[0006] This document describes a method for forming a microelectronic package. The method may include forming an elastomeric pad on a first portion of a base. Sub-assemblies may be formed on the elastomeric pad. A connector assembly may be attached to the first portion. The connector assembly may extend through an opening in the base. The sub-assemblies and the connector assembly may be attached via a flexible electrical connection. A cap may be attached to at least a second portion of the base, the second portion surrounding the first portion. The attachment of the cap to the base may form an hermetically sealed chamber defined by the upper surface of the first portion, the connector assembly, and the inner surface of the cap. Attached Figure Description

[0007] The accompanying drawings described below are for illustrative purposes only. These drawings are not intended to limit the scope of this disclosure.

[0008] Figure 1 This is a top view of the base;

[0009] Figure 2 It shows a cross-sectional view of the base;

[0010] Figure 3 It shows a cross-sectional view of the formation of the elastomer pad;

[0011] Figure 4 This shows a cross-sectional view of a sub-assembly formed on an elastomer pad;

[0012] Figure 5 This is a cross-sectional view showing the formation of a connector assembly of the first type;

[0013] Figure 6 This is a top view of the base, showing the deposition of adhesive;

[0014] Figure 7 This is a cross-sectional view showing the cap being attached to the base to form an encapsulation;

[0015] Figure 8 It is a cross-sectional view showing one or more screws being inserted through one or more screw openings;

[0016] Figure 9 This is a cross-sectional view showing the formation of a second type of connector assembly;

[0017] Figure 10 This is a top view of the base, showing the deposition of adhesive;

[0018] Figure 11 This is a cross-sectional view showing the cap being attached to the base to form an encapsulation;

[0019] Figure 12 It is a cross-sectional view showing one or more screws being inserted through one or more screw openings;

[0020] Figure 13 This is a cross-sectional view showing an exemplary sub-component;

[0021] Figure 14 This is a cross-sectional view showing another exemplary sub-component;

[0022] Figure 15 This is a three-dimensional perspective view of the base;

[0023] Figure 16 It is a three-dimensional perspective view of the lid;

[0024] Figure 17 This is a three-dimensional perspective view of a first-type connector assembly;

[0025] Figure 18 This is a three-dimensional perspective view of the bottom side of the package;

[0026] Figure 19 This is a flowchart illustrating an exemplary process for forming a package; and

[0027] Figure 20 This is a flowchart illustrating an exemplary process for forming sub-components. Detailed Implementation

[0028] In the following detailed description, various examples are described in sufficient detail to enable those skilled in the art to practice the disclosure. It should be understood that other examples may be utilized without departing from the scope of this disclosure. Therefore, the following detailed description is not intended to be limiting.

[0029] This paper describes a packaging technique for microelectromechanical systems (MEMS) devices. This approach combines standard integrated circuit (IC) packaging techniques with isolation structures to minimize errors caused by environmental temperature, shock, and vibration. This method can be used with standard IC mass production techniques and is cost-effective due to the use of readily available materials.

[0030] MEMS devices packaged in this way can be implemented in various sensor systems, such as inertial measurement units (IMUs). This packaging technology addresses the stringent requirements of IMU products employing MEMS sensors in terms of size, cost, and performance.

[0031] In summary, this disclosure relates to microelectronic package (i.e., module) designs in which internal components may include one or more sensor chips and integrated circuits, which are isolated from external shocks and vibrations that may be applied during module operation. The package design may include thermal isolation of the internal components from ambient temperature while minimizing thermal gradients within the module and around the internal components. These features may result in enhanced and more stable performance because the internal components are likely less affected by external vibrations and temperature variations. In the described embodiments, an IMU refers to a MEMS sensor including one or more accelerometers and gyroscopes, as well as electronic circuitry. The IMU may be a monolithic die or a discrete die including the sensor and electronic circuitry.

[0032] This module design may include one or more of the following features: internal vibration damping features, a chamber design allowing for thermally conductive material around one or more semiconductor chips, and built-in connectors that enable electrical connections between internal components and the main printed circuit board (PCB). These electrical connections can be decoupled from major sub-components within the module to meet vibration isolation requirements. In summary, these features provide thermal and vibration isolation between internal components and the environment.

[0033] The module may include a cover and a base. The cover may be configured to provide a locking mechanism to isolate internal components and electrical connections from external insertion / extraction forces (e.g., during PCB assembly). The base may allow electrical connections between internal components and one or more external components (e.g., the PCB). An air chamber within the module may provide additional thermal resistance to minimize heat conduction across the module and to the environment.

[0034] In one example, the internal components of the module may include sub-assemblies. The sub-assembly may include one or more active components. Thermally conductive material may be applied to the one or more active components (e.g., through automated processes) to achieve temperature distribution around the one or more active components. The sub-assembly may be integrated within the module while being isolated from external shocks and vibrations. The module may include connector assemblies to provide electrical connections between the sub-assembly and one or more external components (e.g., a PCB). In one example, the connector assembly may include one or more flexible connectors, interposers, and wire bond assemblies. The connector assembly isolates the sub-assembly from external shocks and vibrations.

[0035] These features, due to improved vibration isolation and thermal stability within the module, can lead to better performance of internal components. Furthermore, the proposed design simplifies assembly and allows for better integrated functionality compared to traditional packaging techniques.

[0036] Now for reference Figure 1The image shows a top view of base 102. Base 102 can be formed from one or more materials, including metals, ceramics, or polymers such as plastics. For applications where base 102 is expected to provide radio frequency (RF) shielding and / or transmit electrical signals, base 102 is formed from metal, or it can be formed from ceramic or plastic with a conductive layer. In one example, base 102 may be formed from pre-molded plastic (e.g., with a lead frame).

[0037] The base 102 may have one or more parts. The first part may be the platform 106, and the second part may be the edge 104. The edge 104 may surround the platform 106. In one example, the shape of the base 102 may be a basic square, rectangle, or circle.

[0038] The base 102 may include one or more openings. For example, the platform 106 portion of the base 102 may include a connector opening 108 and one or more screw openings 110. Although shown as having a rectangular shape, the connector opening 108 may be any desired size and / or shape to accommodate an electrical connector, as described in further detail below. In one example, the one or more screw openings 110 may include four openings located near the corners of the platform 106.

[0039] Now for reference Figure 2 The diagram shows a cross-sectional view of the schematic base 102. This cross-sectional view can be seen from... Figure 1 The angle of line A-A' shown is taken. The edge portion 104 of the base 102 may have a height H. 104 The platform 106 portion of the base 102 can have a height H. 106 .

[0040] Now for reference Figure 3 The diagram shows a cross-sectional view illustrating the formation of an elastomer pad 302. In one example, the elastomer pad 302 may be formed on a platform 106 portion of the base 102. The elastomer pad 302 may be formed on the platform 106. The elastomer pad 302 may be composed of one or more conventional materials capable of absorbing and damping vibrations. The elastomer pad 302 may be composed of materials having a low storage modulus and a relatively high loss modulus. In one example, the elastomer pad 302 may be composed of one or more conventional silicone die adhesives. Some examples of commercially available silicone die adhesives that can be used to form the elastomer pad 302 are... 988 7920 and 245.

[0041] Now for reference Figure 4The diagram shows a cross-sectional view schematically illustrating the formation of a sub-assembly 402 on an elastomeric pad 302. The sub-assembly 402 may include one or more active components, such as semiconductor chips and integrated circuits. Examples of different configurations for the sub-assembly 402 will be described in more detail below.

[0042] In one example, sub-component 402 can be formed separately and can be selected and placed on elastomeric pad 302. In another example, sub-component 402 can be formed in situ on elastomeric pad 302. After sub-component 402 is formed on elastomeric pad 302, elastomeric pad 302 can be cured. By forming sub-component 402 on elastomeric pad 302, sub-component 402 can be isolated from physical forces (e.g., vibration and shock) and temperature gradients that may propagate through base 102.

[0043] Now for reference Figure 5 The diagram shows a cross-sectional view schematically forming a connector assembly 502 of the first type. The connector assembly 502 of the first type may be a flexible electrical connection, such as a flexible printed circuit (FPC), and may include one or more of a flat flexible cable (FFC) 506, a first connector 504, and a second connector 510.

[0044] First connector 504 and second connector 510 can be electrically coupled via FFC 506. FFC 506 can be a miniaturized ribbon cable, which is also flat and flexible. The cable may include a flat and flexible plastic film base with multiple flat metal conductors bonded to a single surface. Each end of the cable can be reinforced with a stiffener to facilitate insertion or provide stress relief. FFC 506 can be used as an alternative to round cables for easier cable management. FFC 506 can occupy less space than round cables and provides better electromagnetic interference (EMI) and radio frequency interference (RFI) suppression while eliminating conductor coupling issues. Furthermore, because the conductors of FFC 506 can be individually protected, rather than being wrapped multiple times with different materials as in round cables, FFC 506 is lighter and offers greater flexibility than conventional cables.

[0045] The first connector 504 and the second connector 510 can be conventional pin connectors (e.g., 30 pins), allowing the first type of connector assembly 502 to be physically and electrically coupled to other devices. For example, the first connector 504 can be attached to one or more components on a PCB. The second connector 510 can be attached to one or more components on the subassembly 402.

[0046] The FFC 506 and the first connector 504 can be attached to the base 102 by applying an adhesive 508 around the periphery of the connector opening 108. The adhesive 508 can be a conventional type of adhesive, such as epoxy or silicone adhesive (e.g., room temperature vulcanizing (RTV) silicone). The adhesive 508 secures the FFC 506 to the base 102 and the first connector 504 within the connector opening 108. In one example, the adhesive 508, FFC 506, and first connector 504 can form an airtight, hermetic seal around the connector opening 108.

[0047] The first type of connector assembly 502 can allow the subassembly 402 to be electrically coupled to external devices while remaining isolated from any type of physical force experienced by the first connector 504.

[0048] Now for reference Figure 6 The diagram shows a top view of the base 102, illustrating the deposition of adhesive 602. Adhesive 602 can be a conventional type of adhesive, preferably having a low curing temperature and low modulus. Adhesive 602 can have a CTE close to that of the base 102 and the cap 702 to avoid any CTE mismatch and reduce stress on the encapsulation. Examples of commercially available adhesives that can be used as the adhesive include... The manufactured "EP21TDC-2LO" and The "SEMICOSIL 988" is manufactured. Adhesive 602 can be deposited on the edge 104 and around one or more screw openings 110.

[0049] Now for reference Figure 7 The diagram shows a cross-sectional view schematically attaching a cover 702 to a base 102 to form a package 710. The cover 702 can be formed from one or more materials, including metals, ceramics, or polymers such as plastics. For applications where the cover 702 is expected to provide radio frequency shielding and / or transmit electrical signals, the cover 702 can be formed from a metal, or it can be formed from a ceramic or plastic with a conductive layer. In one example, the cover 702 can be formed from a pre-molded plastic (e.g., with a lead frame).

[0050] The cover 702 can be designed to complement the shape of the base 102. For example, the cover 702 may include a first portion 706 extending to the upper surface of the platform 106 and a second portion 704 extending to the upper surface of the edge 104. The cover 702 can be secured to the base 102 by an adhesive 602. The adhesive 602 secures the cover 702 to the base 102 and can form an airtight hermetic seal around the edge 104 and one or more screw openings 110. The hermetic seal can form a chamber 708 within the package 710. The chamber 708 can insulate the sub-assembly 402 and can provide thermal resistance to minimize heat conduction across and into / out of the package 710.

[0051] Now for reference Figure 8 The cross-sectional view shows one or more screws 802 inserted through one or more screw openings 110. See below for reference. Figure 16 As described, the cover 702 may include one or more screw openings 1602 that correspond to and align with one or more screw openings 110 in the base 102. One or more screws 802 may extend through the entire thickness of the package 710 and may be used to fasten the package 710 to another device (e.g., a PCB).

[0052] Now for reference Figure 9 The diagram shows a cross-sectional view illustrating the formation of a second type of connector assembly 902. Figure 9 The second type of connector assembly 902 shown can be Figure 5 The first type of connector assembly 502 shown is an alternative, and can be combined with the above references. Figures 1 to 4 All steps described. The second type of connector assembly 902 may include a connector 904, a middleman 906, and a wire bonding portion 908. The connector 904 may be a conventional pin connector (e.g., 30 pins), allowing the second type of connector assembly 902 to be physically and electrically coupled to other devices.

[0053] Connector 904 can be electrically coupled to intermediate 906 via one or more solder joints 910. Intermediate 906 can be a rigid or flexible intermediate and can be composed of one or more of glass-reinforced epoxy laminate (e.g., FR4) and polyimide. In other examples, intermediate 906 can be composed of silicon and / or glass. Intermediate 906 may include one or more vias (not shown) formed of a conductive material (such as a metal or metal alloy). One or more vias can carry electrical signals through intermediate 906 between wire bonding portion 908 and connector 904. Connector 904 can be attached to the cover using adhesive 912 deposited around connector opening 108. In one example, adhesive 912 can be similar to adhesive 602 described above. Adhesive 912 helps to secure intermediate 906 to connector 904 and helps to secure connector 904 in connector opening 108. Adhesive 912 can form an airtight seal around connector opening 108.

[0054] The wire bonding portion 908 can be connected to one or more vias in the intermediate 906. The wire bonding portion 908 can be made of a conductive material, such as metal or metal alloy. The wire bonding portion 908 can also be connected to a bonding pad formed on the sub-assembly 402. The second type of connector assembly 902 can allow the sub-assembly 402 to be electrically coupled to external devices while remaining isolated from any type of physical force experienced by the connector 904.

[0055] Now for reference Figure 10 The image shows a top view of the base 102, illustrating the deposition of adhesive 1002. In one example, adhesive 1002 may be similar to adhesive 602 described above. Adhesive 1002 may be deposited on the intermediary 906, on the edge 104, and around one or more screw openings 110.

[0056] Now for reference Figure 11 The diagram shows a cross-sectional view schematically attaching a cover 1102 to a base 102 to form a package 1110. The cover 1102 can be formed of one or more materials, including metals, ceramics, or polymers such as plastics. For applications where the cover 1102 is expected to provide radio frequency shielding and / or transmit electrical signals, the cover 1102 can be formed of a metal, or it can be formed of a ceramic or plastic with a conductive layer. In one example, the cover 1102 can be formed of a pre-molded plastic (e.g., with a lead frame).

[0057] The cover 1102 can be designed to complement the shape of the base 102. For example, the cover 1102 may include a first portion 1106 extending to the upper surface of the platform 106 and the upper surface of the intermediary 906, and a second portion 1104 extending to the upper surface of the edge 104. The cover 1102 can be secured to the base 102 and the intermediary 906 by an adhesive 1002. The adhesive 1002 secures the cover 1102 to the base 102 and can form an airtight hermetic seal around the edge 104 and one or more screw openings 110. The hermetic seal can form a chamber 1108 within the package 710. The chamber 1108 can insulate the sub-assembly 402 and can provide thermal resistance to minimize thermal conduction across and into / out of the package 1110.

[0058] Now for reference Figure 12 The cross-sectional view illustrates one or more screws 1202 being inserted through one or more screw openings 110. See below for reference. Figure 16 As described, the cover 1102 may include one or more screw openings 1602 that correspond to and align with one or more screw openings 110 in the base 102. One or more screws 1202 may extend through the entire thickness of the package 1110 and may be used to fasten the package 1110 to another device (e.g., a PCB).

[0059] Now for reference Figure 13 A cross-sectional view illustrating an exemplary sub-component 402 is shown. In one example, Figure 13 The sub-assembly 402 shown can be used with the connector assembly 502 of the first type described above. Sub-assembly 402 may include a first laminate layer 1302 attached to the elastomeric pad 302. The first laminate layer 1302 may be composed of a thermally and / or electrically insulating material, such as a glass-reinforced epoxy laminate (e.g., FR4). In one example, the first laminate layer 1302 may be a ring and may include a first opening 1304.

[0060] In one example, the first laminate 1302 can be attached to the bottom surface of the substrate 1306 using a solder reflow process employing surface mount technology (SMT). In another example, the first laminate 1302 can be attached to the bottom surface of the substrate 1306 using a conventional type of adhesive 1322. The adhesive 1322 can have a low curing temperature and a low modulus, and can be similar to the adhesive 602 described above. The substrate 1306 can be composed of one or more of semiconductor materials (e.g., silicon), printed circuit boards (PCBs), and thermally and / or electrically insulating materials (e.g., glass-reinforced epoxy laminates, such as FR4). In one example, the substrate 1306 can be composed of the same material as the first laminate 1302 to reduce or eliminate any CTE mismatch between the two layers.

[0061] The substrate 1306 may include a first copper layer on the bottom surface and a second copper layer on the top surface, thereby forming a two-layer substrate 1306 with a coarser / looserer design rule for the copper traces / widths. The substrate 1306 may also include one or more pin-through-hole (PTH) vias that electrically connect the bottom and top surfaces. This arrangement allows for SMT operations and enables the connection of various components to either side of the substrate 1306 via one or more copper pad terminals.

[0062] The second laminate 1308 may be attached to the top surface of the substrate 1306. In one example, the second laminate 1308 may be attached to the top surface of the substrate 1306 using an SMT solder reflow process. In another example, the second laminate 1308 may be attached to the top surface of the substrate 1306 using an adhesive 1322. The second laminate 1308 may be composed of a thermally and / or electrically insulating material, such as a glass-reinforced epoxy laminate (e.g., FR4). The second laminate 1308 may be a ring and may include a second opening 1310.

[0063] One or more MEMS devices can be attached to substrate 1306 via one or more SMT connections. In one example, a first IMU 1312 can be attached to the bottom surface of substrate 1306 in a first opening 1304. The first IMU 1312 can be attached to substrate 1306 using conventional SMT techniques. For example, solder paste can be printed onto the bottom surface of substrate 1306, the first IMU 1312 can be positioned onto the solder paste stencil using pick-and-place techniques, and reflow, deflow, and baking processes can be performed. In one example, the first IMU 1312 can be attached to substrate 1306 via land grid array (LGA) pins.

[0064] The second IMU 1316 can be attached to the upper surface of the substrate 1306 in the second opening 1310. The second IMU 1316 can also be attached to the substrate 1306 using conventional SMT techniques. For example, solder paste can be printed onto the upper surface of the substrate 1306, the second IMU 1316 can be positioned onto the solder paste stencil using pick-and-place techniques, and reflow, deflow, and baking processes can be performed. In one example, the second IMU 1316 can be attached to the substrate 1306 via Land Grid Array (LGA) pins.

[0065] After the first IMU 1312 and the second IMU 1316 are attached to the substrate 1306, thermal paste (“TCP”) 1314 can be deposited in the first opening 1304 and the second opening 1310, such that it completely surrounds the first IMU 1312 and the second IMU 1316. TCP 1314 minimizes the temperature gradient across the first IMU 1312 and the second IMU 1316 by uniformly distributing heat. The constant volume of TCP 1314 on the first IMU 1312 and the second IMU 1316 results in a reduction / elimination of thermal gradients along the X, Y, and Z axes. The closed volume of TCP 1314, along with the first opening 1304 and the second opening 1310, helps stabilize the temperature to cope with thermal fluctuations. This can significantly improve device performance.

[0066] The TCP 1314 type used can be selected based on one or more characteristics, such as: dispersibility and flowability, ability to fill gaps, conformal coverage around the first IMU 1312 and the second IMU 1316 (e.g., void-free and without air pockets), curing time (e.g., less than one hour) and curing temperature (e.g., less than 100°C), thermal conductivity (e.g., greater than 2 W / mK), low modulus and low shrinkage (Shore A hardness), adhesion to FR4, stability over different temperature ranges (e.g., -40°C to 85°C), resistance to hardening at higher temperatures, and stability under impact and / or vibration.

[0067] TCP 1314 can be silicone-based and composed of a single-part or two-part material. TCP 1314 may include, for example, components capable of [transferring from...]. and Commercially available standard product. TCP 314 can be deposited and optionally cured according to production recommendations.

[0068] In one example, subcomponent 402 may optionally include a microcontroller (MCU) 1318. The MCU 1318 can be attached to the substrate 1306 using conventional SMT techniques such as those described above. The MCU 1318 can be attached to the substrate 1306 via, for example, square flat no-lead (QFN) pins.

[0069] Sub-assembly 402 may also include connector 1320. Connector 1320 may be attached to substrate 1306 using conventional SMT techniques such as those described above. Connector 1320 may be a flexible connector and may serve as an attachment point for the second connector 510 of the connector assembly 502 of the first type described above.

[0070] Now for reference Figure 14 A cross-sectional view illustrating another exemplary sub-component 402 is shown. In one example, Figure 14 The sub-component 402 shown can be used with the connector assembly 902 of the second type described above.

[0071] Figure 14 The sub-component 402 shown can be substantially similar to Figure 13 The sub-component 402 is shown. However, instead of connector 1320, sub-component 402 may include wire bondpad 1402 for attaching wire bond portion 908. Wire bondpad 1402 may be formed on the upper surface of substrate 1306.

[0072] although Figure 13 and 14 The example of the sub-assembly shown includes two IMUs, but sub-assembly 402 may include any number of IMUs and / or other devices and still fall within the scope of this disclosure. For example, it is envisioned that sub-assembly 402 includes one IMU that may be attached to the upper or lower surface of substrate 1306. If sub-assembly 402 includes one IMU (or any other number of IMUs) and other devices located on the upper surface of substrate 1306, then the sub-assembly may not include the first laminate 1302, and substrate 1306 may be directly attached to elastomeric pad 302.

[0073] Now for reference Figure 15The image shows a three-dimensional perspective view of the base 102. As described above, the base 102 may include an edge portion 104, a platform 106, a connector opening 108, and one or more screw openings 110. The platform 106 has a greater height than the edge portion 104, which allows for an airtight seal once the cover 702 is attached. In one example, the area of ​​the platform 106 surrounding the connector opening 108 may include one or more guide pins 1502 to assist in attaching the first connector 504 and / or FFC 506.

[0074] Now for reference Figure 16 The image shows a three-dimensional perspective view of the cover 702. As described above, the cover 702 may include a first portion 706 extending to the upper surface of the platform 106 and a second portion 704 extending to the upper surface of the edge portion 104. The cover 702 may have one or more screw openings 1602 corresponding to one or more screw openings 110 in the base 102. Although a cover 702 for use with a first-type connector assembly 502 is shown, it should be noted that a cover 1102 used with a second-type connector assembly 902 is substantially similar and has similar features, including one or more screw openings 1602.

[0075] Now for reference Figure 17 The diagram shows a three-dimensional perspective view of a first-type connector assembly 502, an elastomer pad 302, and a sub-assembly 402. As described above, the FFC 506 can be attached to the platform 106 portion of the base 102 via an adhesive 508. The FFC 506 can electrically couple a first connector 504 in the connector opening 108 to a second connector 510, and the FFC 506 is attached to the sub-assembly 402 via the second connector 510. The sub-assembly 402 can be attached to the elastomer pad 302, which is formed on the platform 106 portion of the base 102. In this example, the sub-assembly 402 includes at least an MCU 1318, a second IMU 1316, and a second overlay layer 1308.

[0076] Now for reference Figure 18The image shows a three-dimensional perspective view of the bottom side of package 710. It should be noted that package 1110 differs from package 710 in the use of the intermediate 906 and wire bonding portion 908 of the second type of connector assembly 902, although the appearance of package 1110 may be substantially similar to that of package 710. As described above, the cover 702 can be attached to the base using adhesive 602. The base 102 may have one or more screw openings 110 for attaching package 710 to another device. The base 102 may also include a connector opening 108 and a first connector 504 mounted within the connector opening 108. The first connector 504 may be exposed, but it forms an airtight seal with the connector opening 108.

[0077] Now for reference Figure 19 A flowchart illustrating an exemplary process for forming packages 710 and 1110 is shown. In step 1902, an elastomeric pad 302 may be formed on the platform 106 portion of the base 102. In step 1904, a sub-component 402 may be formed on the elastomeric pad 302. In one example, the sub-component 402 may be formed separately and placed on the elastomeric pad 302 using a pick-and-place technique. In step 1906, the elastomeric pad 302 may be cured.

[0078] In step 1908, adhesive may be applied to the base 102. In an example using the first type of connector assembly 502, adhesive 508 may be applied around the connector opening 108, and adhesive 602 may be applied around one or more screw openings 110 and the edge 104. In an example using the second type of connector assembly 902, adhesive 912 may be applied around the connector opening 108, and adhesive 1002 may be applied around one or more screw openings 110 and the edge 104.

[0079] In step 1910, a flexible electrical connector can be attached. In the example using the first type of connector assembly 502, the first connector 504 can be inserted into the connector opening 108, and the FFC 506 can be attached to the base 102 via adhesive 602. The adhesive 602 secures the FFC 506 to the base 102 and holds the first connector 504 within the connector opening 108, thereby forming an airtight hermetic seal. Subsequently, the FFC 506 can be attached to the sub-assembly 402 via the second connector 510. In the example using the second type of connector assembly 902, the connector 904 can be inserted into the connector opening 108. The intermediary 906 can be attached to the connector 904 via one or more solder points 910. The intermediary 906 can be attached to the cover via adhesive 912, which secures the connector 904 within the connector opening 108 and can form an hermetic seal. Wire bonding portions 908 can be attached to bonding pads on the intermediary and bonding pads on the sub-assembly.

[0080] In step 1912, the cover can be placed on the base. In the example using the first type of connector assembly 502, the cover 702 can be secured by adhesive 602 applied around one or more screw openings 110 and on the edge 104. In the example using the second type of connector assembly 902, the cover 1102 can be secured by adhesive 1002 applied around one or more screw openings 110, on the edge 104, and on the median 906. In step 1914, the adhesive can be cured to form an airtight seal.

[0081] Now for reference Figure 20 The diagram illustrates an exemplary process for forming sub-component 402. In step 2002, the bottom surface of substrate 1306 can be prepared for SMT. This may include dispensing solder paste in a predetermined pattern using conventional techniques such as stencils or printing. In step 2004, a first overlay layer 1302 can be attached to the bottom side of substrate 1306 to form a first opening 1304. A first IMU 1312 can be attached to the bottom side of substrate 1306 within the first opening 1304. In step 2006, reflow, deflow, and baking processes can be performed to fix the first overlay layer 1302 and the first IMU 1312.

[0082] In step 2008, the top side of substrate 1306 can be prepared for SMT. This may include dispensing solder paste in a predetermined pattern using conventional techniques such as stencils or printing. In step 2010, a second overlay layer 1308 can be attached to the top side of substrate 1306 to form a second opening 1310. A second IMU 1316 can be attached to the top side of substrate 1306 within the second opening 1310. An MCU 1318 can also be attached to the top side of substrate 1306. In step 2012, a reflow, deflow, and bake process can be performed to fix the second overlay layer 1308, the second IMU 1316, and the MCU 1318. In step 2014, TCP 1314 can be dispensed. In one example, TCP 1314 can be first dispensed to one side of substrate 1306 and cured, and then dispensed to the other side of substrate 1306 and cured. For example, TCP 1314 can be allocated and hardened around the second IMU 1316 in the second opening 1310. Next, TCP 1314 can be allocated and hardened around the first IMU 1312 in the first opening 1304. In another example, TCP 1314 can be allocated to both the first opening 1304 and the second opening 1310 and hardened together.

[0083] Although various aspects of microelectronic packaging and methods of forming microelectronic packages have been disclosed in the context of selected representative examples, those skilled in the art will understand that this disclosure extends beyond the specific disclosed examples to other alternative examples and / or uses, as well as their obvious modifications and equivalents. Furthermore, although different variations have been shown and described in detail, other modifications within the scope of this disclosure will be readily understood by those skilled in the art based on its content. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the examples are possible and remain within the scope of this disclosure. Various features and aspects of the disclosed examples can be combined or substituted with each other to form different modes of the disclosed microelectronic packages. Therefore, the scope of this disclosure should not be limited to the specific examples described above.

Claims

1. A package, comprising: The base includes a first portion surrounded by a second portion; A connector assembly attached to the first portion, the connector assembly extending through an opening in the base; A cover is at least attached to the second portion, the cover forming an airtight chamber defined by the upper surface of the first portion, the connector assembly, and the inner surface of the cover; An elastomer pad on the first part; A sub-assembly on the elastomeric pad, the sub-assembly comprising: (i) a first laminate on the elastomeric pad, the first laminate including a first opening; (ii) a substrate on the first laminate; (iii) a semiconductor chip attached to a lower surface of the substrate, the semiconductor chip being located within the first opening; and (iv) a first thermal paste in the first opening, the first thermal paste surrounding the semiconductor chip; and Flexible electrical connection between the connector assembly and the sub-assembly.

2. The packaging according to claim 1, characterized in that, The semiconductor chip includes a first MEMS sensor.

3. The packaging according to claim 2, characterized in that, The packaging also includes: An integrated circuit chip (IC) on the upper surface of the substrate.

4. The packaging according to claim 3, characterized in that, The packaging also includes: A second laminated layer on the upper surface of the substrate, the second laminated layer including a second opening; A second MEMS sensor attached to the upper surface of the substrate, the second MEMS sensor being located within the second opening; and A second thermal paste is placed inside the second opening, and the second thermal paste surrounds the second MEMS sensor.

5. The packaging according to claim 1, characterized in that, The packaging also includes: One or more mounting holes extend through the base within the first portion; Extending through one or more corresponding mounting openings of the cover, the one or more mounting openings being aligned with the one or more mounting holes; and An adhesive layer that attaches the one or more mounting openings to the first portion.

6. The packaging according to claim 1, characterized in that, The thickness of the first part is greater than the thickness of the second part.

7. The packaging according to claim 1, characterized in that, The connector assembly includes connector pins, and the flexible electrical connection includes a flat flexible cable.

8. The packaging according to claim 1, characterized in that, The connector assembly includes a connector and a mediator.

9. The packaging according to claim 1, characterized in that, The cover is attached to the second part by adhesive.

10. The packaging according to claim 1, characterized in that, The connector assembly is attached to the first part by an adhesive.

11. The packaging according to claim 4, characterized in that, At least one of the first MEMS sensor and the second MEMS sensor includes an inertial measurement unit (IMU).

12. A method of forming an encapsulation, comprising: An elastomer pad is formed on the first part of the base; Forming a sub-assembly on the elastomeric pad, wherein forming the sub-assembly on the elastomeric pad includes: (i) forming a first laminate layer on the elastomeric pad, the first laminate layer including a first opening; (ii) forming a substrate on the first laminate layer; (iii) attaching a semiconductor chip to a lower surface of the substrate, the semiconductor chip being located within the first opening; and (iv) depositing a first thermal paste in the first opening such that the first thermal paste surrounds the semiconductor chip; The connector assembly is attached to the first portion, the connector assembly extending through an opening in the base; The sub-assembly and the connector assembly are connected by a flexible electrical connection; and The cover is attached to at least a second portion of the base to form an airtight chamber defined by the upper surface of the first portion, the connector assembly, and the inner surface of the cover, the second portion surrounding the first portion.

13. The method according to claim 12, characterized in that, The semiconductor chip includes a first MEMS sensor.

14. The method according to claim 13, characterized in that, The method further includes: The IC is attached to the upper surface of the substrate.

15. The method according to claim 14, characterized in that, The method further includes: A second laminate is formed on the upper surface of the substrate, the second laminate including a second opening; A second MEMS sensor is attached to the upper surface of the substrate, the second MEMS sensor being located within the second opening; and A second thermal paste is deposited in the second opening such that the second thermal paste surrounds the second MEMS sensor.

16. The method according to claim 12, characterized in that, The method further includes: One or more mounting holes extending through the base within the first portion will be aligned with one or more corresponding mounting openings extending through the cover; and The one or more mounting openings are attached to the first portion via an adhesive layer.

17. The method according to claim 12, characterized in that, The thickness of the first part is greater than the thickness of the second part.

18. The method according to claim 12, characterized in that, The connector assembly includes connector pins, and the flexible electrical connection includes a flat flexible cable.

19. The method according to claim 12, characterized in that, The connector assembly includes a connector and a mediator.

20. The method according to claim 12, characterized in that, Attaching the cover to the second part includes adhesive bonding.

21. The method according to claim 12, characterized in that, Attaching the connector assembly to the first part includes adhesive bonding.

22. The method according to claim 15, characterized in that, At least one of the first MEMS sensor and the second MEMS sensor includes an IMU.

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