Integrated circuit arrangement with molding compound

Abstract

Arrangement (100) of an integrated circuit, IC arrangement comprising: a first printed circuit board, PCB, (102) having a first surface (104) and an opposite second surface (106); a die (108) electrically coupled to the first surface of the first PCB; a second PCB (110) having a first surface (112) and an opposite second surface (114), a first side (120) and a second side opposite the first side, wherein the second surface of the second PCB is coupled to the first surface of the first PCB via one or more solder connections; and a molding compound (118), wherein the molding compound (118) is in contact with the first surface of the first PCB, the second surface, and one of the first and second sides of the second PCB, the other of the first and second sides of the second PCB not being in contact with the molding compound (118), and wherein the molding compound is not in contact with the die (108).

Description

Technical FieldThe present disclosure relates generally to the field of integrated circuits (ICs), and more particularly to IC assemblies including a molding compound.BackgroundIn existing integrated circuit (IC) devices, printed circuit boards (PCBs) and IC packages may be stacked using conventional connectors and package-on-package techniques. These techniques may be constrained by how small a form factor they can achieve, and thus may not be appropriate for small, next generation powerful devices.US 2007 / 0 108 581 A1 describes an offset integrated circuit stack system comprising providing a base substrate, forming a contact pad on the base substrate, mounting a first integrated circuit on the base substrate, forming a base package body around the first integrated circuit, providing an offset substrate, mounting a second integrated circuit on the offset substrate, and connecting the offset substrate to the contact pad including mounting the offset substrate on the base package body.US 2006 / 0 042 827 A1 describes PDA (SD / MMC) devices and PDA cards in which the substrate on which the PDA components are mounted comprises two planes. High profile components are mounted on the lower level and equipment of normal or low height is mounted on the upper level. The upper layer is contained in the part of the card which corresponds, for example, to the SDA standard thickness of 1.4 mm, while the lower layer is formed in the part of the card which permits a greater thickness, for example, the SDA standard thickness of 2.1 mm.US 2013 / 0 329 378 A1 describes a universal serial bus device comprising a PCB module, a plastic housing shell and a power module. The PCB module includes a printed circuit board, and a memory chip and a control chip both disposed on the PCB module. The circuit board includes front and rear ends and upper and lower surfaces. The upper surface has a number of contact portions, and the memory chip and the control chip are disposed on the lower surface. The plastic package shell encloses at least the bottom surface of the circuit board to encapsulate the memory chip and the control chip. The power module is electrically connected to the portion of the PCB module that is not enclosed by the plastic shell.JP 2008-294 330 A describes a chip-built-in substrate including a semiconductor chip, a first substrate mounted with the semiconductor chip, a second substrate laminated on the first substrate, an electrode electrically connecting the first and second substrates, and a sealing resin disposed between the first and second substrates and. An opening part is formed in the second substrate. When the second substrate is laminated on the first substrate, at least a part of the semiconductor chip is located in the opening part. The first substrate is mounted with a built-in device having a larger shape than the semiconductor chip. The built-in device is located in the opening portion above the chip device.Brief Description of the DrawingsThe embodiments will be readily understood from the following detailed description taken in conjunction with the accompanying drawings. To promote this description, like reference numerals designate like structural elements. The embodiments are illustrated in the figures of the accompanying drawings by way of example and not by way of limitation. FIG. 1 is a side cross-sectional view of an IC assembly according to various embodiments. FIGS. 2 and 3 are top and bottom views, respectively, of an embodiment of the IC package of FIG. 1. FIGS. 4-11 illustrate side cross-sectional views of various arrangements after various operations in the fabrication of an IC arrangement as illustrated in FIG. 1, in accordance with various embodiments. FIG. 12 is a side cross-sectional view of an IC assembly according to various embodiments. FIGS. 13-22 illustrate side cross-sectional views of various devices after various operations in fabricating an IC device as illustrated in FIG. 12, according to various embodiments. FIGS. 23 and 24 are side cross-sectional views of IC assemblies according to various embodiments. FIG. 25 is a flow diagram of an illustrative process for fabricating an IC device, according to various embodiments. FIG. 26 is a block diagram of an example computing device that may include one or more of any of the IC arrangements disclosed herein.SUMMARY OF THE INVENTIONThe object on which the invention is based is achieved by the subject matter of the independent claim. Further advantageous embodiments are specified in the dependent claims.DETAILED DESCRIPTIONDisclosed herein are embodiments of integrated circuit (IC) devices and related techniques. Figures 1 to 23 and the related embodiments contribute to explaining the invention, but are not according to the invention. In some embodiments, an IC assembly may include a first printed circuit board (PCB) having a first surface and an opposing second surface; a die electrically coupled to the first surface of the first PCB, a second PCB having a first surface and an opposing second surface, the second surface of the second PCB coupled to the first surface of the first PCB via one or more solder joints; and a molding compound. The molding compound may be in contact with the first surface of the first PCB and the second surface of the second PCB. In such embodiments, the molding compound may be in contact with the die; in other such embodiments, the molding compound may not be in contact with the die. In some embodiments, an IC assembly may include a PCB having a first surface and an opposing second surface; a die electrically coupled to the first surface of the first PCB; a molding compound having a first surface and an opposing second surface, the second surface of the molding compound being in contact with the first surface of the PCB and a contact being made with the die through the molding compound; and one or more through mold solder connections extending from the first surface of the PCB through the molding compound and beyond the second surface of the molding compound.The IC assemblies and techniques disclosed herein may enable miniaturization of existing IC devices, which reduces the form factors of these devices. Reducing the size of the devices may enable new applications for these devices (e.g., in portable applications for other applications where available area is limited). In addition, providing more computing power in a smaller form may allow for improved performance for the devices that remain sized.For example, the IC assemblies and techniques disclosed herein may be used to provide a solid-state storage drive that is smaller than any conventional drive with an equivalent capacity. These drives may be included in the smaller next generation platforms, such as ultrabooks, tablets, and laptop-tablet hybrids. Some embodiments of the IC assemblies disclosed herein may provide a solid state drive with a high level of component integration. An IC device may include an application specific integrated circuit (ASIC), memory (e.g., a NAND die or package), passive components, and power management circuitry. In contrast, the existing solid state drives may include certain components (e.g., the power system) in a separate arrangement (e.g., on a motherboard).The form factor of the solid state drives disclosed herein may match or exceed the next generation targets. For example, various embodiments of the IC assemblies disclosed herein may provide solid state drives that conform to specifications for the 22 millimeter by 42 millimeter M.2 card format. In another example, various embodiments of the IC assemblies disclosed herein may provide solid state drives conforming to specifications for the 22 millimeter by 30 millimeter M.2 card format. Some embodiments of solid state drives formed in accordance with the IC assemblies and techniques disclosed herein may be thinner than existing drives in all three dimensions.The IC assemblies disclosed herein may have any of a number of advantages. For example, in some embodiments, an IC package may include a post-dicing die disposed on one surface of a PCB (which may or may not be in contact with a molding compound), while the IC packages may be surface mounted on the other surface of the PCB. By coupling the die to one surface of the PCB, more space may be left on the other surface of the PCB for surface mounting of IC packages.Conventional techniques may not be able to achieve these reduced form factors. Some conventional designs mount an ASIC package, a NAND die or package, power modules, and passive components on a single-sided PCB on the surface. Conventional PCB techniques cannot enable coupling of high input / output (I / O) dies after dicing into chips in PCBs in a cost effective manner. In particular, conventional die packaging techniques may not provide for achieving sufficient yield for high I / O dies. Various embodiments of the IC assemblies disclosed herein may include a surface provided by a PCB. Any suitable discrete top components may be attached to the PCB surface (e.g., to form a system in an assembly). Unlike conventional techniques, these upper components may not be subject to any particular coupling requirements (e.g., for ballout or pinout). The ease of access to such components (and the ability to remove and / or replace these components) can allow high yields of final assembly and high test yields as compared to some conventional system-in-assembly approaches (in which all assemblies are encapsulated). In addition, as the requirements for the electronic products change, surface-mounted components can be easily replaced in the manufacturing process, improving design flexibility.Embodiments of the IC arrangements disclosed herein may include both an ASIC and a non-volatile memory device (e.g., flash memory). In some embodiments, the ASIC and the non-volatile memory device in the IC array may be separate, which reduces the likelihood of thermal damage to the temperature sensitive non-volatile memory from the ASIC (which may be a major heat dissipating component).FIG. 1 is a side cross-sectional view of an IC assembly 100, according to various embodiments. The IC assembly 100 may include a first printed circuit board (PCB) 102, a die 108, a second PCB 110, and a molding compound 118. The functionality of the IC device 100 may be determined by the circuitry included in or on the components of the IC device 100. For example, in some embodiments, the IC array 100 may include components arranged to form a solid state drive. By appropriately selecting and arranging the components of the IC device 100, any other suitable functionality may be provided by the IC device 100.The first PCB 102 may include a first surface 104 and a second surface 106 opposite the first surface 104. The first PCB 102 may be formed from any conventional PCB materials (e.g., laminates and copper) and may include any desired number of layers. In some embodiments, the first PCB 102 may be a four-layer PCB. The first PCB 102 may include conductive contacts formed on the first surface 104 and / or the second surface 106, and vias between the first surface 104 and the second surface 106 to couple the electrical signals along and between the surfaces 104 and 106. Examples of the conductive contacts may include traces, pads, fingers, or any suitable conductive interconnect component. The shape of a conductive contact may vary depending on the application. For example, in some embodiments, the traces may be used to conduct signals, the fingers may be exposed for wire bonding or connecting to a socket, and the pads may be used for surface mount, probe contact, or test.The die 108 may include a first surface 124, a second surface 194, and the side surfaces 122. As shown, the second surface 194 may be proximate the first surface 104 of the first PCB 102. In some embodiments, the die 108 may be electrically coupled to the first surface 104 of the first PCB 102. For example, in some embodiments, the die 108 may be wire-bonded to the first surface 104 of the first PCB 102. The wires included in the wire bonds may extend from the first surface 124, the side surfaces 122, or the second surface 194 of the die 108. The electrical signals transmitted by the electrical coupling between the die 108 and the first surface 104 may be further transmitted through the first PCB 102 and to / from other components electrically coupled to the first surface 104 and / or the second surface 106. Examples of such components are discussed below. In some embodiments, the die 108 may be mechanically coupled (e.g., via an adhesive and / or an electrical coupling mechanism such as wire bonding or soldering) to the first surface 104 of the first PCB 102. In some embodiments, the die 108 may be attached using a flip-chip process. Although only a single die 108 is illustrated in FIG. 1, multiple dies may be attached to the first surface 104 of the first PCB 102.The die 108 may include a silicon or other semiconductor material and multiple devices configured to perform a desired function. The devices included in the die 108 may be any suitable type of electronic device (e.g., discrete or integrated devices, transistor-based devices, etc.). In some embodiments, the die 108 may be, for example, an application specific integrated circuit (ASIC). The ASIC may serve any of a number of functions depending on the application. For example, in some embodiments where the IC device 100 is a solid state drive, an ASIC may serve as a controller that manages and connects the external data bus (e.g., ATA and peripheral component interface serial signals). The die 108 may include a single piece of silicon or multiple pieces of silicon and may include any suitable type of electronic components. In various embodiments, any electronic device may be used as the die 108. Additionally, multiple dies 108 (e.g., of varying sizes, types, and functions) may be included in the IC package 100, although the die 108 may be referred to in singular herein.In some embodiments, the die 108 may have undergone substantially no further processing than being cut from a semiconductor wafer on which the electrical devices have been built. Die 108 may be, for example, one of many dies formed in an array on a silicon wafer, and may not have been substantially processed more than being separated from the other dies in the array in a dicing process. Such dies may be referred to herein as "dies after dicing.". Because a die 108 after dicing may be much thinner than a die that has been subjected to additional steps of package placement (e.g., adding external protection components) that performs the same function, the use of a die 108 after dicing in the IC package 100 may allow the IC package 100 to achieve a reduced thickness 130 relative to the use of a die further in a package. In some embodiments, a die after dicing may be, for example, tens of microns thick, while dies further packaged may be hundreds of microns thick.The second PCB 110 may also be coupled to the first surface 104 of the first PCB 102. In particular, the second PCB 110 may include a first surface 112 and an opposing second surface 114, where the second surface 114 may be coupled to the first surface 104 of the first PCB 102. In some embodiments, the second surface 114 of the second PCB 110 may be coupled to the first surface 104 of the first PCB 102 via one or more solder joints 116. In some embodiments, the solder joints 116 may be through mold solder joints, and may be embedded in or through the molding compound 118. The second PCB 110 may be formed of any conventional PCB materials and may include any desired number of layers. In some embodiments, the second PCB 110 may be a second-layer PCB. The second PCB 110 may include conductive contacts formed on the first surface 112 and / or the second surface 114 and through holes between the first surface 112 and the second surface 114 to couple the electrical signals along and between the surfaces. For example, the conductive contacts formed on the second surface 114 may be in contact with the solder joints 116, the second PCB 110 may include vias between these conductive contacts and the conductive contacts on the first surface 112, and these vias may couple the electrical signals from the first PCB 102 to the first surface 112 via the solder joints 116. In some embodiments, the electrical signals may be transmitted along such paths between the die 108 and the first surface 112 of the second PCB 110. In some embodiments, intervening structures or devices (not shown) may be disposed between the first PCB 102 and the second PCB 110. The second surface 114 of the second PCB 110 and the first surface 104 of the first PCB 102 may be separated by a distance 126. In some embodiments, the distance 126 may be less than one millimeter. In some embodiments, flip-chip components, passive components, or other components may be attached to the first surface 104 of the first PCB 102 via one or more solder joints (formed as described above with respect to the solder joints 116) in addition to or in place of the second PCB 110.The first PCB 102 may have a length 128, while the second PCB 110 may have a length 188. The lengths 128 and 188 may take any desired values sufficient to accommodate the desired components in the IC package 100. In some embodiments, the length 128 may be greater than the length 188. In some embodiments, the length 128 may be about equal to the length 188. In some embodiments, the length 128 may be less than the length 188. In some embodiments, the length 128 of the first PCB 102 may be about 42 millimeters. In some embodiments, the length 128 of the first PCB 102 may be about 30 millimeters. In some embodiments, the length 188 of the second PCB 110 may be about 12 millimeters.The die 108 may be disposed in any of a number of ways with respect to the first surface 104 of the first PCB 102 and the second surface 114 of the second PCB 110. For example, in some embodiments, the die 108 may be arranged to be disposed between the second surface 114 of the second PCB 110 and the first surface 104 of the first PCB 102. In some embodiments, the die 108 may not be disposed between the second surface 114 of the second PCB 110 and the first surface 104 of the first PCB 102 (e.g., as illustrated in FIG. 1 ). In some embodiments, the die 108 may be partially disposed between the second surface 114 of the second PCB 110 and the first surface 104 of the first PCB 102.The molding compound 118 may include a first surface 136 and a second surface 192. In the embodiment of FIG. 1, the mold compound 118 is illustrated as being in contact with the die 108. In some embodiments, the molding compound 118 may at least partially cover the die 108. For example, in some embodiments, the molding compound 118 may be in contact with the side surfaces 122 of the die 108 and cover the side surfaces 122 of the die 108. As used herein, the term "covering" a surface or article may refer to contacting with substantially all portions of the surface or article that are not in contact with or covered by other components. In some embodiments, the molding compound 118 may be in contact with the side surfaces 122 and cover the side surfaces 122, and may be in contact with the first surface 124. In some embodiments, the molding compound 118 may cover the first surface 124. In some embodiments, where there is a "gap" between the second surface 194 of the die 108 and the first surface 104 of the first PCB 102, the molding compound 118 may be in contact with the second surface 194. In some embodiments, the molding compound 118 may cover the side surfaces 122 and the first surface 124 of the die 108. In some embodiments, the molding compound 118 may cover the die 108. In some embodiments, the first surface 136 of the molding compound 118 may be spaced apart from the first surface 124 of the die 108 (e.g., by an intermediate portion of the molding compound 118 as shown). In some embodiments, the second surface 192 of the molding compound 118 may be substantially coplanar with the second surface 194 of the die 108.The molding compound 118 (e.g., the second surface 192 of the molding compound 118) may be in contact with the first surface 104 of the first PCB 102 and may be in contact with the second surface 114 of the second PCB 110. In some embodiments, the molding compound 118 may cover the first surface 104 of the first PCB 102. In some embodiments, the molding compound 118 may cover the second surface 114 of the second PCB 110. In some embodiments, the molding compound 118 may cover the solder joints 116. As indicated above, in some embodiments, the molding compound 118 may not be in contact with the die 108. Some examples of such embodiments are discussed below with respect to FIG. 24.Any suitable molding compound may be used as the molding compound 118. For example, encapsulating epoxy plastic material, a resin, or any other suitable molding compound typically used in package placement applications may be used. Each of these materials may or may not contain fillers or other particles such as silica fillers. The molding compound 118 may be formed by any suitable process, such as the molding processes discussed below and illustrated with respect to FIGS. 7-10.The IC assembly 100 may include a first surface 134 and a second surface 132. In some embodiments, the first surface 134 may include at least a portion of the first surface 112 of the second PCB 110. In some embodiments, the first surface 134 may include at least a portion of the first surface 136 of the molding compound 118. In some embodiments, the first surface 134 may include at least a portion of the first surface 112 of the second PCB 110 and at least a portion of the first surface 136 of the molding compound 118 (e.g., as shown in FIG. 1 ). In particular, the first surface 112 of the second PCB 110 may be substantially coplanar with the first surface 136 of the molding compound 118. In some embodiments, the first surface 134 may be substantially entirely provided by the first surface 136 of the molding compound 118. In other embodiments, the first surface 134 may be substantially completely provided by the first surface 112 of the second PCB 110. In some embodiments, the first surface 134 may be spaced apart from the first surface 136 of the molding compound 118 and / or the first surface 112 of the second PCB 110. In some such embodiments, additional components may be disposed between the first surface 134 and the first surface 136 of the molding compound 118 and / or between the first surface 134 and the first surface 112 of the second PCB 110. For example, additional PCBs may be disposed between the first surface 136 of the molding compound 118 and the first surface 134 and / or between the first surface 112 of the second PCB 110 and the first surface 134. The additional PCBs may take the form of any of the PCBs discussed herein. For example, the IC assembly 100 may include more than two PCBs, where these PCBs may be coupled together in any desired arrangement using solder connections similar to the solder connections 116. In some embodiments, the IC package 100 may include three or more PCBs.In some embodiments, the second surface 132 may include at least a portion of the second surface 106 of the first PCB 102. In some embodiments, the second surface 132 may be substantially completely provided by the second surface 106 of the first PCB 102 (e.g., as shown in FIG. 1 ). In some embodiments, the second surface 132 may include at least a portion of the second surface 192 of the molding compound 118 (not shown). In some embodiments, the second surface 132 may be spaced apart from the second surface 106 of the first PCB 102. In some such embodiments, additional components may be disposed between the second surface 106 of the first PCB 102 and the second surface 132. For example, the additional PCBs may be disposed between the first PCB 102 and the second surface 132 (e.g., according to any of the embodiments discussed above with respect to the first surface 134).In each of the foregoing embodiments, the first surface 134 and / or the second surface 132 may have a protective coating (e.g., a plastic coating, not shown) disposed thereon. Such coatings may be conventional and will not be discussed further herein.In some embodiments, the IC package 100 may include additional components. For example, the IC assembly 100 may include one or more probe pads 140. The probe pads 140 may be disposed on the first surface 134 of the IC assembly 100 (e.g., on the first surface 112 of the second PCB 110 as shown in FIG. 1 ). In some embodiments, the probe pads may be disposed on the second surface 132 of the IC assembly 100 (e.g., on the second surface 106 of the first PCB 102). Each of the probe pads 140 may be a conductive region (e.g., a flat portion of metal) electrically coupled to one or more other components in the IC assembly 100. In some embodiments, the probe pads 140 may be used to provide a contact point through which to test various components within the IC device 100 (e.g., various circuitry included in the die 108 or disposed on the second PCB 110 or the first PCB 102). Example tests may include open circuit / short circuit detection and / or evaluation of performance of various components.The IC assembly 100 may include one or more IC packages surface mounted on the second surface 106 of the first PCB 102 and / or the first surface 112 of the second PCB 110. In FIG. 1, the IC packages 142- 148 are illustrated as being surface mounted to the second surface 106 of the first PCB 102. In the illustrated embodiment, the second surface 106 of the first PCB 102 matches the second surface 132 of the IC package 100. Any desired IC package may be surface mounted to one or more of the PCBs 102 and 110 included in the IC package 100. The IC package 142 may be, for example, a temperature sensor. The IC package 144 may include one or more passive components, such as resistors and capacitors. The IC package 146 may be a power management integrated circuit (PMIC). The IC package 148 may be a memory device such as flash memory. In some embodiments, the IC package 148 may be a NAND flash memory having a ball grid array (BGA) for surface mounting to the second surface 132 of the IC package 100. In some embodiments, one or more of the IC packages 142- 148 may not be surface-mounted to the second surface 106 of the first PCB 102, but instead may be coupled to the first surface 104 (e.g., in a form after dicing) as discussed above with respect to the die 108. In particular, in some embodiments, the IC package 144, 146, and / or 148 may be so coupled. Other devices (e.g., one or more crystals) may be surface mounted to the IC assembly 100. In some embodiments, the IC packages may be disposed on the second surface 132 of the IC package 100, and no IC packages may be disposed on the first surface 134 of the IC package 100.As illustrated in FIG. 1, the IC packages 142- 148 (surface mounted to the second surface 132 of the IC assembly 100) may not be covered by the molding compound 118. In particular, in some embodiments, any IC packages included on the first surface 134 or the second surface 132 of the IC package 100 (e.g., the IC packages 142- 148) may be surface mounted to the second surface 132 after the molding compound 118 is provided to the IC package 100. Because such packages are not embedded in the molding compound, the packages can be easily attached, replaced, or removed during the lifetime of the IC package 100.The first surface 134 and / or the second surface 132 of the IC assembly 100 may include one or more conductive contacts that may be used to enable electrical coupling between the circuitry of the IC assembly 100 and an external socket or other coupling component. For example, as shown in FIG. 1, one or more conductive contacts 150 may be disposed on the second surface 132 of the IC assembly 100 (e.g., on the second surface 106 of the first PCB 102). One or more conductive contacts 152 may be disposed on the first surface 134 of the IC assembly 100 (e.g., on the first surface 112 of the second PCB 110). In some embodiments, the conductive contacts 150 may be printed on the first PCB 102 prior to coupling the die 108 to the first surface 104 of the first PCB 102. In some embodiments, the conductive contacts 150 and / or 152 may be printed on the first PCB 102 and / or the second PCB 110, respectively, before the first PCB 102 and the second PCB 110 are coupled via the one or more solder joints 116. In some embodiments, the conductive contacts 150 and / or 152 may be printed on the first PCB 102 and / or the second PCB 110, respectively, before the molding compound is provided to the IC assembly 100.The conductive contacts 150 and / or 152 may be disposed at any desired location on a surface of the IC assembly 100. In some embodiments, the conductive contacts 150 and / or 152 may be disposed directly at an end of the IC assembly 100 (e.g., as shown in FIG. 1 ). In particular, the conductive contacts 150 and / or 152 may be a part of a border finger connector that may be received by a complementary socket in an external device and that may be used to electrically and mechanically couple the IC assembly 100 to the external device. Various examples of such embodiments are discussed below with respect to FIGS. 2 and 3.FIGS. 2 and 3 are top and bottom views, respectively, of an embodiment of the IC package 100. In particular, FIGS. 2 and 3 illustrate an embodiment in which the IC assembly 100 includes an edge finger connector 168 for mechanically and electrically coupling to a socket of an external device, as discussed above. A number of embodiments of the edge finger connector 168 are illustrated in FIGS. 2 and 3 and will be discussed below. Other features of the embodiments of FIGS. 2 and 3 discussed below may be included in the IC assembly 100, whether or not the IC assembly 100 includes an edge finger connector 168.FIG. 2 is a top view of an embodiment of the IC assembly 100. In particular, FIG. 2 illustrates the second surface 132 of the IC assembly 100, in accordance with some embodiments. The IC assembly 100 may have a length 128 (e.g., as discussed above with respect to FIG. 1 ) and a width 170. In some embodiments, the length 128 may be equal to the length of the PCB 102. In some embodiments, the width 170 may be equal to the width of the PCB 102. The width 170 may take any desired value sufficient to accommodate the components desired in the IC package 100. In some embodiments, the width 170 may be about 22 millimeters, for example.As discussed above with respect to FIG. 1, one or more IC packages may be disposed on the second surface 132. For example, FIG. 2 shows that temperature sensor 142, passive components 144, PMIC 146, and a storage device 148 are disposed on second surface 132. The arrangement of IC packages 142-148 in FIG. 1 is simply illustrative, and any desired arrangement may be used. For example, in some embodiments, temperature sensor 142 may be disposed in region 196 laterally aligned with memory device 148 in width direction 170 of IC assembly 100.The edge finger connector 168 may include three protrusions 154A, 154B, and 154C. Each of the protrusions 154A, 154B, and 154C may include one or more conductive contacts 150 (i.e., the conductive contacts 150A, 150B, and 150C, respectively). In some embodiments, conductive contacts 150A may include six conductive contacts, conductive contacts 150B may include nineteen conductive contacts, and conductive contacts 150C may include five conductive contacts. In some embodiments, the conductive contacts 150 may be gold contacts, and may be printed on the second surface 106 of the first PCB 102. The number and geometry of the protrusions in the edge finger connector 168 (optionally), and the number, distribution, and geometry of the conductive contacts 150 may be selected to enable connection between the edge finger connector 168 and a desired socket.FIG. 3 is a bottom view of an embodiment of the IC package 100. In particular, FIG. 3 illustrates the first surface 134 of the IC assembly 100, in accordance with some embodiments. The IC assembly 100 may have a length 128 and a width 170 (e.g., as discussed above with respect to FIGS. 1 and 2 ). FIG. 3 also illustrates an example of the relative positioning of the die 108 in the IC package 100. As discussed above, the die 108 may be covered by the molding compound 118.As discussed above with respect to FIG. 1, one or more probe pads 140 may be disposed on the first surface 134. As illustrated in FIG. 3, the probe pads 140 may take any of a number of different sizes and shapes and may be arranged as desired. In some embodiments, the probe pads 140 may be printed on the first surface 112 of the second PCB 110. The second PCB 110 may also include conductive vias between the probe pads 140 and the second surface 114 of the second PCB 110. The signals may be transmitted between the probe pads 140 and the other circuitry of the IC package 100 through these conductive vias. In some embodiments, the probe pads 140 may be formed of a metal material (e.g., copper) and may be covered with another metal (e.g., gold, tin, palladium, or silver) or an organic thin layer to prevent oxidation.As discussed with respect to FIG. 2, each edge finger connector 168 may include three protrusions 154A, 154B, and 154C. Each of the protrusions 154A, 154B, and 154C may include one or more conductive contacts 152 (i.e., the conductive contacts 152A, 152B, and 152C, respectively). For example, in some embodiments, conductive contacts 152A may include five conductive contacts, conductive contacts 152B may include twenty conductive contacts, and conductive contacts 152C may include four conductive contacts. In some embodiments, the conductive contacts 152 may be gold contacts, and may be printed on the first surface 112 of the second PCB 110. The number and geometry of the protrusions in the edge finger connector 168 (optionally), and the number, distribution, and geometry of the conductive contacts 152 may be selected to enable connection between the edge finger connector 168 and a desired socket.As noted above, the dimensions of the IC device 100 may take any desired values. In some embodiments, the width of the IC assembly 100 may be, for example, 12, 16, 22, or 30 millimeters. In some embodiments, the length of the IC assembly 100 may be 16, 26, 30, 38, 42, 60, 80 or 110 millimeters. These dimensions are simply illustrative, and any desired dimensions may be used.FIGS. 4-11 illustrate side cross-sectional views of various devices after various operations in the fabrication of an IC device, in accordance with various embodiments. For ease of illustration, the arrangements illustrated in FIGS. 4-11 may represent various stages in the fabrication of the IC device 100, but the operations discussed with respect to FIGS. 4-11 may be used to fabricate any suitable IC device. In various embodiments, one or more of these operations may be omitted, repeated, or performed in an alternative order as appropriate.In addition, FIGS. 4-11 illustrate the operations performed on a single IC device 100, but this is simple for ease of illustration. In some embodiments, a number of IC devices 100 (e.g., tens of devices) may be formed in parallel. For example, multiple IC devices 100 may be formed in one device, and the operations discussed with respect to FIGS. 4-11 may be performed simultaneously or in any suitable order on the device. After an array of the IC arrays 100 is formed, the array may be cut into pieces (not illustrated in FIGS. 4-11 ) to segment the IC arrays 100 from each other. Batch manufacturing of the IC package 100 may improve throughput.FIG. 4 illustrates an arrangement 400 after forming a conductive contact 150 on the second surface 106 of the first PCB 102. On the second surface 106, one or more conductive contacts 150 may be formed. In some embodiments, the conductive contact 150 may be printed on the second surface 106 using conventional PCB patterning techniques. In some embodiments, the conductive contacts 150 may be the pads for surface mounting. The first PCB 102 may include additional conductive contacts on the second surface 106 and / or on the first surface 104 arranged to couple to the components to be attached in subsequent operations. As discussed above, the first PCB 102 may also include conductive vias between the first surface 104 and the second surface 106 to couple the electrical signals between the surfaces. The arrangement of these contacts and vias may be planned according to the arrangement of the additional components included in the IC assembly 100 using conventional PCB design techniques.FIG. 5 illustrates an assembly 500 after coupling the die 108 to the first surface 104 of the first PCB 102 of the assembly 400. In particular, the second surface 194 of the die 108 may be disposed directly on the first surface 104 of the first PCB 102. As discussed above with respect to FIG. 1, the coupling between the die 108 and the first PCB 102 may take any of a number of forms. For example, in some embodiments, the die 108 may be wire-bonded to the first PCB 102. In some embodiments, the die 108 (e.g., a silicon die or any other electronic device) may be attached using a flip-chip technique.FIG. 6 illustrates an assembly 600 after coupling the second PCB 110 to the first PCB 102 of the second assembly 500. The coupling of the second PCB 110 to the first PCB 102 may be achieved using a BGA ball attach process. In particular, the second surface 114 of the second PCB 110 may be coupled to the first surface 104 of the first PCB 102 via one or more solder joints 116. When coupling the second PCB 110 to the first PCB 102, the solder joints 116 may have a thickness 602 representing a distance between the first surface 104 of the first PCB 102 and the second surface 114 of the second PCB 110. The assembly 600 may have a thickness 604. In some embodiments, the second PCB 110 may include one or more probe pads 140 and / or one or more conductive contacts 152 disposed on the first surface 112.The probe pads 140 and the conductive contacts 152 may be printed on the second PCB 110 prior to coupling the second PCB 110 to the first PCB 102. The probe pads 140 and the conductive contacts 152 may be formed using conventional PCB fabrication techniques.The second PCB 110 may include additional conductive contacts on the first surface 112 and / or on the second surface 114 arranged to be electrically coupled to the die 108, the first PCB 102, and / or the components to be attached in subsequent operations. For example, the second surface 114 of the second PCB 110 and the first surface 104 of the first PCB 102 may include conductive contacts arranged to contact the solder joints 116 to provide conductive paths between the first PCB 102 and the second PCB 110. As discussed above, the second PCB 110 may also include conductive vias between the first surface 112 and the second surface 114 to couple the electrical signals between the surfaces. The arrangement of these contacts and vias may be planned according to the arrangement of the additional components included in the IC assembly 100 using conventional PCB design techniques.FIG. 7 illustrates an assembly 700 after securing the assembly 600 in a mold chassis 704. The mold chassis 704 may include the interior walls 706 that define an interior chamber 708. The dimensions of the inner chamber 708 may be selected to correspond to the assembly 600 in some portions, but also to leave one or more open volumes (e.g., volume 710). As noted above, in some embodiments, an array of the arrays 600 may take the form of a unitary body, which unitary body may be secured within a mold chassis having the form of an array of the shapes of the mold chassis 704.Additionally, the inner chamber 708 may have some dimensions that are slightly smaller than those of the assembly 600. For example, a "thickness" dimension 714 of the chamber 708 may be slightly less than the thickness 604 of the assembly 600. When the assembly 600 is inserted into the mold chassis 704 and the mold chassis 704 is closed, the assembly 600 may be compressed (e.g., as indicated by arrows 702). The components of the assembly 600 that are deformable may deform in response to this compression. In particular, the solder joints 116 may be sufficiently deformable (e.g., less deformable than the other components of the assembly 600) to be deformed by the pressure from the mold chassis 704 and decrease in thickness (e.g., by undergoing a controlled collapse). The thickness 712 of the solder joints 116 after compression in the mold chassis 704 may be less than the thickness 602 of the solder joints 116 of the assembly 600. Thus, the thickness 714 of the assembly 700 after compression in the mold chassis 704 may be less than the thickness 604 of the assembly 600. Using the pressure from the mold chassis 704 to form the solder joints 116 until the thickness 714 of the assembly 700 matches the internal dimensions of the chamber 708 may allow the thickness 714 to be accurately controlled to a desired value regardless of the variation in the thickness 602 of the solder joints 116 of the assembly 600 typically caused by the surface tension forces when the solder joints 116 are initially formed.FIG. 8 illustrates an assembly 800 after the molding compound 118 is provided in the volume 710 of the chamber 708 of the mold chassis 704 to contact the assembly 700. The molding compound 118 may be provided to fill the volume 710. As discussed above with respect to FIG. 1, in some embodiments, the molding compound 118 may be in contact with the first surface 104 of the first PCB 102. In some embodiments, the molding compound 118 may be in contact with the second surface 114 of the second PCB 110. In some embodiments, the molding compound 118 may cover the solder joints 116. In some embodiments, the molding compound 118 may cover the die 108. As shown in FIG. 8, the second surface 192 of the molding compound 118 may be in contact with the first surface 104 of the first PCB 102, while the first surface 136 may be in contact with the walls 706 of the mold chassis 704. Any of a number of forming techniques may be used to form the arrangements described herein. For example, injection molding may be used. In some embodiments, the transfer molding process may be advantageous.FIG. 9 illustrates an assembly 900 after the molding compound 118 of the assembly 800 has cured. Once cured, the molding compound 118 may be substantially rigid. In some embodiments, the forming process discussed above with respect to FIGS. 7-9 may be an exposed shape process. In some embodiments, the assembly 900 may be cured after being removed from the mold chassis 704. In some embodiments, curing may be initiated or accelerated, for example, by heating or the use of ultraviolet light.FIG. 10 illustrates the assembly 900 after removing the assembly 900 from the mold chassis 704 of FIG. 9. The assembly 900 may include a first surface 134 and a second surface 132.FIG. 11 illustrates an assembly 1100 after surface mounting of one or more IC packages (e.g., IC packages 142- 148) to the second surface 132 of the assembly 900. The array 1100 may be the IC array 100. The first PCB 102 may include conductive contacts on the second surface 106 to couple to the conductive contacts of the surface mount IC packages, and conductive vias between the first surface 104 and the second surface 106 to couple the electrical signals between the surface mount IC packages and the die 108 and / or the second PCB 110. The conductive contacts 150 of the first PCB 102 and the conductive contacts 152 of the second PCB 110 may be used to couple the signals between one or more external devices (not shown) and any of the components of the IC assembly 100 (e.g., any of the IC packages 142- 148 and / or the die 108). The operation of the IC device 100 may take the form of any of the embodiments discussed herein.FIG. 12 is a side cross-sectional view of an IC assembly 1200 disposed on a motherboard 1240, according to various embodiments. The IC assembly 1200 may include a printed circuit board (PCB) 1202, a die 1208, a molding compound 1218, and one or more through mold solder connections 1216. The functionality of the IC device 1200 may be determined by the circuitry included in or on the components of the IC device 1200. For example, in some embodiments, IC package 1200 may include components arranged to form any of the devices described above with respect to IC package 100. Any other suitable functionality may be provided by the IC device 1200 through the appropriate selection and arrangement of the components of the IC device 1200.The PCB 1202 may include a first surface 1204 and a second surface 1206 that is opposite the first surface 1204. The PCB 1202 may be formed of any conventional PCB materials and may include any desired number of layers. The PCB 1202 may include conductive contacts formed on the first surface 1204 and / or the second surface 1206 and vias between the first surface 1204 and the second surface 1206 to couple the electrical signals along and between the surfaces 1204 and 1206.The die 1208 may include a first surface 1224, a second surface 1294, and the side surfaces 1222. As shown, the second surface 1294 may be located directly on the first surface 1204 of the PCB 1202. In some embodiments, the die 1208 may be electrically coupled to the first surface 1204 of the PCB 102. For example, in some embodiments, the die 1208 may be wire-bonded to the first surface 1204 of the PCB 1202. The wires included in the wire bonds may extend from the first surface 1224, the side surfaces 1222, or the second surface 1294 of the die 108. The electrical signals transmitted by the electrical coupling between the die 1208 and the first surface 1204 may be further transmitted through the PCB 1202 and to / from the other components electrically coupled to the first surface 1204 and / or the second surface 1206 (e.g., the components surface mounted to the second surface 1206 and / or coupled to the PCB 1202 via the through mold solder joints 1216, as discussed below). In some embodiments, the die 1208 may be mechanically coupled to the first surface 1204 of the PCB 1202 (e.g., via an adhesive and / or an electrical coupling mechanism such as wire bonding or soldering). In some embodiments, the die 1208 may be attached using a flip-chip process. Although only a single die 1208 is illustrated in FIG. 12, multiple dies may be attached to the first surface 1204 of the PCB 1202.The die 1208 may take the form of any of the dies 108 discussed above with respect to FIG. 1. Die 1208 may include, for example, a silicon or other semiconductor material and multiple devices (e.g., transistor-based devices) configured to perform a desired function. In some embodiments, die 1208 may be, for example, an ASIC (e.g., any of the ASICs discussed above with respect to die 108). In some embodiments, the die 1208 may be a die after dicing into chips. Because a die 1208 after dicing may be much thinner than a further-in-package die performing the same function, the use of a die 1208 after dicing in dies in the IC package 1200 may allow the IC package 1200 to achieve a reduced thickness 1230 relative to the use of a further-in-package die. The die 1208 may include a single piece of silicon or multiple pieces of silicon and may include any suitable type of electronic components. The molding compound 1218 may include a first surface 1236 and a second surface 1292, and may be in contact with the die 1208. For example, in some embodiments, the molding compound 1218 may be in contact with the side surfaces 1222 of the die 1208 and cover the side surfaces 1222 of the die 1208. In some embodiments, the molding compound 1218 may be in contact with the side surfaces 1222 and cover the side surfaces 1222, and may be in contact with the first surface 1224. In some embodiments, the molding compound 1218 may cover the first surface 1224. In some embodiments, where there is a "gap" between the second surface 1294 of the die 1208 and the first surface 1204 of the PCB 1202, the molding compound 1218 may be in contact with the second surface 1294. In some embodiments, the molding compound 1218 may cover the side surfaces 1222 and the first surface 1224 of the die 1208. In some embodiments, the molding compound 1218 may cover the die 1208. In some embodiments, the first surface 1236 of the molding compound 1218 may be spaced apart (e.g., by an intermediate portion of the molding compound 1218 as shown) from the first surface 1224 of the die 1208. In some embodiments, the first surface 1236 may be substantially coplanar with the first surface 1224. In some embodiments, the second surface 1292 of the molding compound 1218 may be substantially coplanar with the second surface 1294 of the die 1208.The molding compound 1218 (e.g., the second surface 1292 of the molding compound 1218) may be in contact with the first surface 1204 of the PCB 1202. In some embodiments, the molding compound 1218 may cover the first surface 1204 of the PCB 1202. In some embodiments, the molding compound 1218 may cover the through mold solder connections 1216.Any suitable molding compound may be used as the molding compound 1218, such as any of the examples discussed above with respect to the molding compound 118 of FIG. 1. The molding compound 1218 may be molded by any suitable process, such as the molding processes discussed below and illustrated with respect to FIGS. 15-18.The IC assembly 1200 may include a first surface 1234 and a second surface 1232. In some embodiments, the first surface 1234 may include at least a portion of the first surface 1236 of the molding compound 1218 (e.g., as shown in FIG. 12 ). In some embodiments, the first surface 1234 may be substantially entirely provided by the first surface 1236 of the molding compound 1218. In some embodiments, the first surface 1234 may include the first surface 1236 of the molding compound 1218, and may include the through mold solder joints 1216 extending through the first surface 1236 of the molding compound 1218. In some embodiments, the first surface 1234 may be spaced apart from the first surface 1236 of the molding compound 1218. In some such embodiments, additional components may be disposed between the first surface 1234 and the first surface 1236 of the molding compound 1218. For example, additional PCBs and other components may be disposed between the first surface 1236 of the molding compound 1218 and the first surface 1234. The additional PCBs may take the form of any of the PCBs discussed herein. For example, the IC assembly 1200 may include more than one PCB, where these PCBs may be coupled together in any desired arrangement (e.g., using solder connections similar to the solder connections 116 discussed above with respect to the IC assembly 100).In some embodiments, the second surface 1232 may include at least a portion of the second surface 1206 of the PCB 1202. In some embodiments, the second surface 1232 may be substantially entirely provided by the second surface 1206 of the PCB 1202 (e.g., as shown in FIG. 12 ). In some embodiments, the second surface 1232 may include at least a portion of the second surface 1292 of the molding compound 1218 (not shown). In some embodiments, the second surface 1232 may be spaced apart from the second surface 1206 of the PCB 1202. In some such embodiments, additional components may be disposed between the second surface 1206 of the PCB 1202 and the second surface 1232. For example, additional PCBs may be disposed between the PCB 1202 and the second surface 1232 (e.g., according to any of the embodiments discussed above with respect to the first surface 1234).In each of the foregoing embodiments, the first surface 1234 and / or the second surface 1232 may include a protective coating (e.g., a plastic coating, not shown) disposed thereon. Such coatings may be conventional and are not discussed further herein.As indicated above, the IC assembly 1200 may include one or more through mold solder connections 1216. The through mold solder joints 1216 may electrically couple the die 1208 and the motherboard 1240 via the PCB 1202. In particular, the through mold solder connections 1216 may make electrical contact with the conductive contacts on the first surface 1204 of the PCB 1202. The die 1208 may be electrically coupled to the PCB 1202 (e.g., via one or more conductive contacts or via the wire bonds on the first surface 1204 of the PCB 1202), as discussed above. The PCB 1202 may include one or more vias that may couple the signals between the contacts on the first surface 1204 to different layers in the PCB 1202, to the electrical contacts on the second surface 1206, or to other electrical contacts on the first surface 1204. In some embodiments, the electrical signals may be transmitted between the die 1208 and the through mold solder joints 1216 through such electrical paths. When the through mold solder joints 1216 are in contact with the electrical contacts on the motherboard 1240, signals may be transmitted between the motherboard 1240 and the die 1208. In some embodiments, the conductive contacts and / or the vias may be formed prior to coupling the die 1208 to the first surface 1204 of the PCB 1202, prior to providing the molding compound 1218 to the IC assembly 1200, and / or prior to providing the through mold solder connections 1216 in the PCB 1202.As used herein, a motherboard may refer to any circuit board on which the IC assembly 1200 may be disposed and to which the IC assembly 1200 may be coupled via the through mold solder joints 1216. Thus, in some embodiments, through mold solder joints 1216 may be considered to provide second level connections between motherboard 1240 and IC assembly 1200. The structure illustrated in FIG. 12 may be contrasted with some conventional approaches for placement into packages in which a mold may be on top of a substrate, while any second level interconnects may be on the bottom, the opposite side of the substrate facing the motherboard.In some embodiments, the IC assembly 1200 may include additional components. For example, the IC assembly 1200 may include one or more probe pads 1260. The probe pads 1260 may be disposed on the second surface 1232 of the IC assembly 1200 (e.g., on the second surface 1206 of the PCB 1202 as shown in FIG. 12). The probe pads 1260 may take the form of any of the embodiments of the probe pads 140 discussed above with respect to the IC assembly 100. In some embodiments, probe pads 1260 may not be included in IC assembly 1200.The IC assembly 1200 may include one or more IC packages surface mounted on the second surface 1206 of the PCB 1202. In FIG. 12, the IC packages 1254 and 1256 are illustrated as being surface mounted on the second surface 1206 of the PCB 1202. In the illustrated embodiment, the second surface 1206 of the PCB 1202 matches the second surface 1232 of the IC assembly 1200. Any desired IC package may be surface mounted to the second surface 1206 of the PCB 1202. For example, any of the IC packages 142- 148 discussed above with respect to the IC package 100 may be surface mounted to the second surface 1232 of the IC package 1200. In some embodiments, IC packages 1254 and 1256 may include, for example, non-volatile memory, dynamic random access memory (DRAM), a power system, or passive components. In some embodiments, some of the IC packages 1254 and 1256 may not be surface-mounted to the second surface 1206 of the PCB 1202, but instead may be coupled (e.g., in a form after dicing) to the first surface 1204, as discussed above with respect to the die 1208.As illustrated in FIG. 12, the IC packages 1254 and 1256 surface-mounted to the second surface 1232 of the IC assembly 1200 may not be covered by the molding compound 1218. In particular, in some embodiments, any IC packages included on the second surface 1232 of the IC assembly 1200 (e.g., the IC packages 1254 and 1256) may be surface mounted on the second surface 1232 after the molding compound 1218 is provided to the IC assembly 1200. Because such packages are not embedded in the molding compound, the packages can be easily attached, replaced, or removed during the lifetime of the IC package 1200.The through-holes included in the PCB 1202 may be used to couple the electrical signals between any of the IC packages surface mounted to the second surface 1232 of the IC assembly 1200 and the die 1208. The through-holes included in the PCB 1202 and the through-mold solder joints 1216 may be used to couple the electrical signals between any of the IC packages surface mounted to the second surface 1232 of the IC assembly 1200 and the motherboard 1240.The second surface 1232 of the IC assembly 1200 and / or the motherboard 1240 may include one or more conductive contacts that may be used to enable electrical coupling between the circuitry of the IC assembly 1200 and the external devices (not shown).In some embodiments (e.g., the embodiments in which the IC assembly 1200 implements a solid state drive), the area of the second surface 1206 of the PCB 1202 (e.g., on which the IC packages 1254 and 1256 are disposed) may be less than 400 square millimeters. The range may be, for example, about 20 millimeters by 20 millimeters. This may accommodate a non-volatile memory package that is 14 millimeters by 18 millimeters and a PMIC package that is 4 millimeters by 4 millimeters. An area greater than 120 square millimeters may be available for additional components (e.g., passive component assemblies).The "height" of the IC assembly 1200 may vary by the application and desired components. For example, in some embodiments, the solder stud 1242 may be about 200 micrometers, the thickness 1244 of the mold cap may be about 210 micrometers, the substrate thickness 1246 may be about 200 micrometers, and the height 1248 of the upper component may be about 800 micrometers (resulting in an overall height including a tolerance of about 1500 micrometers). In some embodiments, the solder stud 1242 may be about 200 micrometers, the thickness 1244 of the mold cap may be about 200 micrometers, the substrate thickness 1246 may be about 200 micrometers, and the height 1248 of the upper component may be about 650 micrometers (resulting in an overall height including a tolerance of about 1350 micrometers). In some embodiments, the solder stud 1242 may be about 100 micrometers, the thickness 1244 of the mold cap may be about 210 micrometers, the substrate thickness 1246 may be about 130 micrometers, and the height 1248 of the upper component may be about 500 micrometers (resulting in an overall height including a tolerance of about 1000 micrometers). The IC arrays 1200 (e.g., solid state drives) having these dimensions may be advantageously included in small electronic devices (e.g., handheld mobile devices).FIGS. 13-22 illustrate side cross-sectional views of various devices after various operations in the fabrication of an IC device according to various embodiments. For ease of illustration, the arrangements illustrated in FIGS. 13-22 may represent various stages in the fabrication of the IC arrangement 1200, but the operations discussed with respect to FIGS. 13-22 may be used to fabricate any suitable IC arrangement. In various embodiments, one or more of these operations may be omitted, repeated, or performed in an alternative order as appropriate.Additionally, as discussed above with respect to FIGS. 4-11, FIGS. 13-22 illustrate operations performed with respect to a single IC array 1200, which is simple for ease of illustration. In some embodiments, a number of IC arrays 1200 (e.g., tens of arrays) may be formed in parallel. For example, multiple IC arrays 1200 may be formed in one array, and the operations discussed with respect to FIGS. 13-22 may be performed on the array simultaneously or in any suitable order. After an array of the IC arrays 1200 is formed, the array may be cut into pieces (not illustrated in FIGS. 13-22 ) to segment the IC arrays 1200 from each other. Batch manufacturing of the IC assembly 1200 may improve throughput.FIG. 13 illustrates an assembly 1300 after the PCB 1202 is provided. The PCB 1202 may include conductive contacts on the second surface 1206 and / or on the first surface 1204 that are arranged to be coupled to the components to be attached in subsequent operations. As discussed above, the PCB 1202 may also include conductive vias between the first surface 1204 and the second surface 1206 to couple the electrical signals between the surfaces. The arrangement of these contacts and vias may be scheduled according to the arrangement of the additional components to be included in the IC assembly 1200 using conventional PCB design techniques.FIG. 14 illustrates an arrangement 1400 after coupling the die 1208 to the first surface 1204 of the PCB 1202 of the arrangement 1300. In particular, the second surface 1294 of the die 1208 may be disposed directly on the first surface 1204 of the PCB 1202. As discussed above with respect to FIG. 12, the coupling between the die 1208 and the PCB 1202 may take any of a number of forms. For example, in some embodiments, the die 1208 may be wire-bonded to the PCB 1202.FIG. 15 illustrates assembly 1400 secured within mold chassis 1504. The mold chassis 1504 may include the inner walls 1506 defining an inner chamber 1508. The dimensions of the inner chamber 1508 may be selected to correspond in some portions of the assembly 1400, but also to leave one or more open volumes (e.g., volume 1510).FIG. 16 illustrates an assembly 1600 after providing the molding compound 1218 in the volume 1510 of the chamber 1508 of the mold chassis 1504 to contact the assembly 1400. The molding compound 1218 may be provided to fill the volume 1510. As discussed above with respect to FIG. 12, in some embodiments, the molding compound 1218 may be in contact with the first surface 1204 of the first PCB 1202. In some embodiments, the molding compound 1218 may cover the die 1208. As shown in FIG. 16, the second surface 1292 of the molding compound 1218 may be in contact with the first surface 1204 of the PCB 1202, while the first surface 1236 may be in contact with the walls 1506 of the mold chassis 1504. As noted above, any of a number of forming techniques may be used to form the arrangements described herein. For example, injection molding may be used. In some embodiments, the transfer molding process may be advantageous.FIG. 17 illustrates an assembly 1700 after the molding compound 1218 of the assembly 1600 has cured. The molding compound 1218, once cured, may be substantially rigid. In some embodiments, the molding process discussed above with respect to FIGS. 15-17 may be an exposed shape process.FIG. 18 illustrates the assembly 1700 (FIG. 17 ) after removing the assembly 1700 from the mold chassis 1504 of FIG. 17. The assembly 1700 may include a first surface 1234 and a second surface 1232.FIG. 19 illustrates an assembly 1900 after forming one or more holes in the molding compound 1218 of the assembly 1800 to form one or more cavities 2002. The cavities 2002 may be located at the positions where through mold solder joints are to be formed. The cavities 2002 may be formed by drilling through the molding compound 1218 (e.g., using a laser drilling process) until the conductive contacts are exposed on the first surface 1204 of the PCB 1202. As discussed above, these conductive contacts may be formed on the first surface 1204 of the PCB 1202 prior to coupling the die 1208 and prior to providing the molding compound 1218. In some embodiments, the voids 2002 may be several hundred micrometers deep or less and may have a diameter of several hundred micrometers to about 1 millimeter. Other dimensions may be used.FIG. 20 illustrates an assembly 2000 after depositing a solderable material in the cavities 2002 of the second assembly 1900 to form the through mold solder joints 1216. Examples of a solderable material include solder balls (e.g., those used for a BGA) and solder paste. Through mold solder joints 1216 may extend beyond first surface 1236 of molding compound 1218, as shown in FIG. 20. In some embodiments, forming the solder joints 1216 may include two or more phases of depositing a solderable material (e.g., in the form of a solder ball) and reflowing the material. In some embodiments, a first portion of the solderable material may be deposited on the first surface 1204 of the PCB 1202 prior to any forming operations, wherein the first portion of the solderable material may be exposed after the forming process (e.g., by drilling) and additional solderable material may be deposited on the first portion of the solderable material to form the solder joints 1216.FIG. 21 illustrates an assembly 2100 after surface mounting one or more IC packages (e.g., IC packages 1254 and 1256) to the second surface 1232 of the assembly 2000. The array 2100 may be the IC array 1200. The PCB 1202 may include conductive contacts on the second surface 1206 to couple to the conductive contacts of the surface mount IC packages, and conductive vias between the first surface 1204 and the second surface 1206 to couple the electrical signals between the surface mount IC packages and the die 1208 and / or the through mold solder connections 1216.FIG. 22 illustrates an assembly 2200 after coupling the IC assembly 2100 (e.g., the IC assembly 1200) to the motherboard 1240. In particular, through mold solder joints 1216 may be coupled to the conductive contacts on motherboard 1240 to allow electrical signals to flow between IC assembly 2200 and motherboard 1240. The operation of the IC assembly 2200 may take the form of any of the embodiments discussed herein.As indicated above, in some embodiments, two or more PCBs 110 may be coupled to the first surface 104 of the first PCB 102. In some embodiments, any one or more of the PCBs 110 coupled to the first surface 104 of the first PCB 102 may include "windows" or other cut-out portions through which components (e.g., dies) may be coupled to the first surface 104 of the first PCB 102. FIG. 23 is a side cross-sectional view of an embodiment of the IC assembly 100 including the first PCB 102, the die 108, the molding compound 118, and two second PCBs 110 aand 110 b. The remaining elements of the IC device 100 of FIG. 23 may take the form of any of the similar element embodiments discussed above with respect to FIG. 1. In some embodiments, the IC array 100 of FIG. 23 may include components arranged to form a solid state drive. Any other suitable functionality may be provided by the IC device 100 through appropriate selection and arrangement of the components of the IC device 100 of FIG. 23. The fabrication of the IC package 100 of FIG. 23 may be performed substantially in accordance with the operations discussed above with respect to FIGS. 4-11 with modifications to adapt to the differences in structure.As indicated above, in some embodiments, the molding compound 118 may not be in contact with the die 108. An example of such an embodiment is illustrated in FIG. 24, which illustrates a side cross-sectional view of an embodiment of the IC package 100. The remaining elements of the IC assembly 100 of FIG. 24 may take the form of any of the similar element embodiments discussed above with respect to FIG. 1. As shown in FIG. 24, in some embodiments, a side surface 138 of the molding compound 118 may be spaced apart from the die 108. In other embodiments, the molding compound 118 may be in contact with the side surface 122 of the die 108, but may not be in contact with the first surface 124. The embodiments where the molding compound 118 is not in contact with the die 108 may be advantageous when the die 108 is flip-chip mounted to the first surface 104 of the first PCB 102. In particular, heat dissipation from the die 108 may be improved by keeping a flip-chip die 108 uncovered by the molding compound 118. In some embodiments, a flip chip die 108 may be contacted by the molding compound 118 on the side surfaces 122. The fabrication of the IC package 100 of FIG. 24 may be performed substantially in accordance with the operations discussed above with respect to FIGS. 4-11 with modifications to adapt to the differences in structure. For example, the die 108 may be attached (e.g., flip-chip attached) after the forming process is completed or before the forming process begins.FIG. 25 is a flow diagram of an illustrative process 2500 for manufacturing an IC device, according to various embodiments. Although the operations of process 2500 may be discussed with respect to IC devices 100 and 1200 (and components thereof), this is simply for illustrative purposes, and process 2500 may be used to fabricate any suitable IC device.At 2502, a die may be coupled to a first surface of the PCB. For example, the die 108 may be coupled to the first surface 104 of the PCB 102 as discussed above with respect to the IC assembly 100 (FIGS. 1, 23, and 24 ). In another example, the die 1208 may be coupled to the first surface 1204 of the PCB 1202 as discussed above with respect to the IC assembly 1200 (FIG. 12 ). The die may be coupled to the first surface of the PCB using any suitable technique (e.g., the techniques disclosed herein).At 2504, a molding compound may be deposited to contact the first surface of the PCB 102. In some embodiments, the molding compound may be in contact with the die. For example, the molding compound 118 may be deposited to contact the first surface 104 of the PCB 102 and at least partially cover the die 108 in the IC assembly 100 (FIGS. 1 and 23 ). In another example, the molding compound 1218 may be deposited to contact the first surface 1204 of the PCB 1202 and at least partially cover the die 1208 in the IC assembly 1200 (FIG. 12 ). In other embodiments, the molding compound may not contact the die (FIG. 24 ). The molding compound may be deposited using any suitable technique (e.g., the techniques discussed herein with respect to FIGS. 7-10 and 15-18).At 2506, one or more IC packages may be coupled to a second surface of the PCB. The second surface of the PCB may be opposite the first surface of the PCB. For example, one or more IC packages 142- 148 may be coupled to the second surface 106 of the PCB 102 in the IC assembly 100 (FIGS. 1, 23, and 24 ). In another example, one or more IC packages 1254 and 1256 may be coupled to the second surface 1206 of the PCB 1202 in the IC assembly 1200 (FIG. 12 ). Then, the process 2500 may end.In some embodiments, process 2500 may include additional operations. For example, in some embodiments, the PCB of 2502 may be a first PCB, wherein the process 2500 may include coupling a second surface of the second PCB to the first surface of the first PCB via one or more solder joints. The second surface 114 of the second PCB 110 may be coupled to the first surface 104 of the first PCB 102, e.g., via the one or more solder joints 116. In some embodiments, the one or more solder joints may be compressed prior to depositing the molding compound at 2504 to reduce its thickness.In some embodiments, after depositing the molding compound 2504, one or more voids may be formed in the molding compound to expose one or more conductive contacts on the first surface of the PCB, wherein a solderable material may be deposited in the voids to form solder joints. For example, through mold solder joints 1216 may be provided to IC assembly 1200 by forming voids in molding compound 1218 and filling the voids with the solderable material (e.g., as discussed above with respect to FIGS. 19-20 ).In some embodiments, the IC assembly formed according to process 2500 may be attached to a motherboard (e.g., via one or more through mold solder connections as discussed above with respect to IC assembly 1200 of FIG. 12 ).In some embodiments, depositing the molding compound at 2504 may include securing the die and the PCB in a mold chassis, providing the molding compound in the mold chassis to contact the first surface of the PCB, and curing the molding compound.The embodiments of the present disclosure may be implemented in a system using any suitable hardware that may benefit from the structures of the IC assemblies and the fabrication techniques disclosed herein. FIG. 26 schematically illustrates a computing device 2600, in accordance with some implementations, which may include one or more of any of the IC assemblies disclosed herein (e.g., those formed in accordance with the IC assembly 100 of FIGS. 1, 23, and 24 and / or the IC assembly 1200 of FIG. 12). In particular, in some embodiments, the embodiments of the IC arrays discussed above with respect to the IC array 100 may be configured as the computing device 2600 or as a portion of the computing device 2600. For example, the IC package 100 may be configured as a storage device 2608 of the computing device 2600 (discussed below). In some embodiments, the embodiments of the IC arrays discussed above with respect to IC array 1200 may be configured as computing device 2600 or as a portion of computing device 2600.Computing device 2600 may be, for example, a mobile communication device or a desktop or rack-based computing device. Computing device 2600 may house a board, such as motherboard 2602. The motherboard 2602 may include a number of components including (but not limited to) a processor 2604 and at least one communication chip 2606. Each of the components discussed herein with respect to computing device 2600 may be disposed in an IC package (such as IC package 100 of FIGS. 1, 23, or 24, or IC package 1200 of FIG. 12). Processor 2604 may be physically and electrically coupled to motherboard 2602. In some implementations, the at least one communication chip 2606 may be physically and electrically coupled to the motherboard 2602. In further implementations, communication chip 2606 may be part of processor 2604.Computing device 2600 may include a storage device 2608. In some embodiments, the memory device 2608 may take the form of any of the embodiments of the IC device 100 or the IC device 1200 discussed herein. In some embodiments, storage device 2608 may include one or more solid state drives. Examples of the storage devices that may be included in the storage device 2608 include volatile memory (e.g., DRAM), nonvolatile memory (e.g., read only memory, ROM), flash memory, and mass storage devices (such as hard disk drives, compact disk (CDs), digital versatile disks (DVDs), etc.).Computing device 2600 may include other components that may or may not be physically and electrically coupled to motherboard 2602, depending on its applications. These other components may include, but are not limited to, a graphics processor, a digital signal processor, a crypto processor, a chipset, an antenna, a display, a touchscreen display, a touchscreen controller, a battery, an audio codec, a video codec, a power amplifier, a global positioning system (GPS) device, a compass, a Geiger counter, an accelerometer, a gyroscope, a speaker, and a camera. In various embodiments, any one or more of these components may be formed as the IC device 100 and / or the IC device 1200.The communication chip 2606 and the antenna may enable wireless communication for transmitting data to and from the computing device 2600. The term "wireless" and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communication channels, etc., that may transmit data through the use of modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated devices do not contain wires, although in some embodiments they might not contain. The communication chip 2606 may implement any one or any of a number of wireless standards or protocols, including, but not limited to, the Electrical and Electronics Engineers (IEEE) institution standards including the Wi-Fi (the IEEE 802.11 family), the IEEE 802.16 standards (e.g., the IEEE 802.16-2005 revision), the long term development project (LTE), along with any modifications, updates, and / or revisions (e.g., the advanced LTE project, the ultra-mobile broadband (UMB) project (also referred to as "3GPP2"), etc.). The IEEE 802.16 compatible broadband wide area networks (BWA) are generally referred to as WiMAX networks, an acronym that stands for worldwide interworking capability for microwave access, which is a meritorious for products passing compliance and interworking tests for the IEEE 802.16 standards. The communication chip 2606 may operate in accordance with a GSM network, a General Packet Radio Service (GPRS) network, a Universal Mobile Telecommunications System (UMTS) network, a high speed packet access (HSPA) network, an evolved HSPA (E-HSPA) network, or an LTE network. The communication chip 2606 may operate according to enhanced data for GSM evolution (EDGE), GSM EDGE radio access network (GERAN), UTRAN or evolved UTRAN (E-UTRAN). The communication chip 2606 may operate in accordance with both CDMA, Time Division Multiple Access (TDMA), Digital Enhanced Cordless Telecommunications (DECT), Data Optimized Evolution (EV-DO), their derivatives, and other wireless protocols referred to as 3G, 4G, 5G, and beyond. The communication chip 2606 may operate according to other wireless protocols in other embodiments.Computing device 2600 may include a plurality of communication chips 2606. For example, a first communication chip 2606 may be dedicated to shorter range wireless communications such as Wi-Fi and Bluetooth, while a second communication chip 2606 may be dedicated to longer range wireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE, EV-DO, and others. In some embodiments, communication chip 2606 may support wired communications. Computing device 2600 may include one or more wired servers.Processor 2604 and / or communication chip 2606 of computing device 2600 may include one or more dies or other components in an IC package. The term "processor" may refer to a device or portion of a device that processes electronic data from registers and / or memory to transform that electronic data into other electronic data that may be stored in the registers and / or memory. In various embodiments, the dies may be included in the IC device 100 and / or the IC device 1200.In various implementations, the computing device 2600 may be a laptop, a netbook, a notebook, an ultrabook, a smartphone, a tablet, a personal digital assistant (PDA), an ultra-mobile PC, a mobile phone, a desktop computer, a server, a printer, a scanner, a monitor, a set-top box, an entertainment control unit, a digital camera, a portable music player, or a digital video recorder. In further implementations, computing device 2600 may be any other electronic device that processes data. In some embodiments, the IC arrangement disclosed herein may be implemented in a high-performance computing device.The following sections provide examples, which examples aid in explaining the invention but are not in accordance with the invention. Example 1 is an IC assembly including: a first PCB having a first surface and an opposing second surface; a die electrically coupled to the first surface of the first PCB; a second PCB having a first surface and an opposing second surface, the second surface of the second PCB coupled to the first surface of the first PCB via one or more solder joints; and a molding compound, the molding compound in contact with the first surface of the first PCB and the second surface of the second PCB.Example 2 may include the subject matter of Example 1, and may further specify that the die is an ASIC.Example 3 may include the subject matter of any of Examples 1-2, and may further specify that a distance between the second surface of the first PCB and the first surface of the second PCB is less than 1 millimeter.Example 4 may include the subject matter of any of Examples 1-3, and may further specify that the first PCB has a length in a first direction and that the second PCB has a length in the first direction that is less than the length of the first PCB.Example 5 may include the subject matter of any of Examples 1-4, and may further specify that the molding compound is in contact with the die.Example 6 may include the subject matter of any of Examples 1-5, and may further specify that the first surface of the second PCB includes a plurality of conductive contacts.Example 7 may include the subject matter of any of Examples 1-6, and may further specify that the molding compound is not in contact with the die.Example 8 may include the subject matter of Example 7, and may further specify that the die is flip-chip mounted to the first surface of the first PCB.Example 9 may include the subject matter of any of Examples 1-8, and may further include one or more IC packages surface-mounted to the second surface of the first PCB.Example 10 may include the subject matter of any of Examples 1-9, and may further specify that the die is electrically coupled to the first surface of the first PCB via one or more wire bonds.Example 11 may include the subject matter of any of Examples 1-10, and may further specify that the solder joints are covered by the molding compound.Example 12 may include the subject matter of any of Examples 1-11, and may further specify that the IC assembly includes an edge finger connector, the edge finger connector including conductive contacts on the second surface of the first PCB.Example 13 may include the subject matter of Example 12, and may further specify that the edge finger connector includes conductive contacts on the first surface of the second PCB.Example 14 may include the subject matter of any of Examples 1-13, and may further specify that the IC device is a solid state drive.Example 15 may include the subject matter of any of Examples 1-14, and may further specify that a width of the IC assembly is about 22 millimeters.Example 16 may include the subject matter of Example 15, and may further specify that a length of the IC assembly is about 42 millimeters.Example 17 is an IC assembly including: a PCB having a first surface and an opposing second surface; a die electrically coupled to the first surface of the PCB; a molding compound having a first surface and an opposing second surface, the second surface of the molding compound being in contact with the first surface of the PCB and a contact with the die being made through the molding compound; and one or more through mold solder connections extending from the first surface of the PCB through the molding compound and beyond the second surface of the molding compound.Example 18 may include the subject matter of Example 17, and may further specify: the IC assembly has a first surface and an opposing second surface; the second surface of the IC assembly includes the second surface of the PCB; and one or more IC packages are surface mounted to the second surface of the PCB.Example 19 may include the subject matter of Example 18, and may further specify that the one or more IC packages are not surrounded by a molding compound.Example 20 may include the subject matter of any of Examples 17-19, and may further specify that the through mold solder joints are coupled to a motherboard such that the die is disposed between the PCB and the motherboard.Example 21 is a method of manufacturing an IC assembly, including: coupling a die to a first surface of a PCB, the PCB having a second surface opposite the first surface; depositing a molding compound to contact the first surface of the PCB; and coupling one or more IC packages to the second surface of the PCB.Example 22 may include the subject matter of Example 21, and may further specify that the PCB is a first PCB, and may further include: coupling a second surface of a second PCB to the first surface of the first PCB via one or more solder joints having a first thickness; and before depositing the molding compound, compressing the one or more solder joints to a second thickness that is less than the first thickness.Example 23 may include the subject matter of any of Examples 21-22, and may further include: after depositing the molding compound, forming one or more voids through the molding compound to expose one or more conductive contacts on the first surface of the PCB; and depositing a solderable material to form solder joints in the one or more voids.Example 24 may include the subject matter of Example 23, and may further include attaching the IC assembly to a motherboard via the solder joints.Example 25 may include the subject matter of any of Examples 21-24, and may further specify that depositing the molding compound includes: after coupling the die to the first surface of the PCB, securing the die and the PCB in a mold chassis; providing the molding compound in the mold chassis to contact the first surface of the PCB; and curing the molding compound.Explanation of CharactersFIGS. 25:2502 Couple a die to a first surface of a first PCB 2504 Deposit a molding compound to contact the first surface of the first PCB 2506 Couple one or more IC packages to a second surface of the PCBFIG. 26 : 2600 computing device 2602 motherboard 2604 processor 2606 communication chip 2608 storage device CAMERA camera CHIPSET chipset AMP amplifier GRAPHICS CPU graphics CPU TOUCH SCREEN CONTROLLER touch screen controller COMPASS compass SPEAKER loudspeaker TOUCH SCREEN DISPLAY touch screen display BATTERY battery ANTENNA antenna

Claims

An integrated circuit, IC, assembly (100) comprising: a first printed circuit board, PCB, (102) having a first surface (104) and an opposing second surface (106); a die (108) electrically coupled to the first surface of the first PCB; a second PCB (110) having a first surface (112) and an opposing second surface (114), a first side (120), and a second side opposing the first side, wherein the second surface of the second PCB is coupled to the first surface of the first PCB via one or more solder joints; and a molding compound (118), wherein the molding compound (118) is in contact with the first surface of the first PCB, the second surface, and one of the first or second sides of the second PCB, wherein the other of the first and second sides of the second PCB is not in contact with the molding compound (118), and wherein the molding compound is not in contact with the die (108).The IC device (100) of claim 1, wherein the die (108) is an application specific integrated circuit, ASIC.The IC assembly (100) of claim 1, wherein a distance (126) between the second surface (106) of the first PCB (102) and the first surface (112) of the second PCB (110) is less than 1 millimeter.The IC assembly (100) of claim 1, wherein the first PCB (102) has a length in a first direction and the second PCB (110) has a length in the first direction that is less than the length of the first PCB (102).The IC assembly (100) of claim 1, wherein the first surface (112) of the second PCB (110) comprises a plurality of conductive contacts.The IC assembly (100) of claim 1, wherein the die (108) is flip-chip mounted to the first surface of the first PCB (102).The IC assembly (100) of claim 1, further comprising: one or more IC packages surface mounted to the second surface (106) of the first PCB (102).The IC assembly (100) of claim 1, wherein the die (108) is electrically coupled to the first surface (104) of the first PCB (102) via one or more wire bonds.The IC package (100) of claim 1, wherein the solder connections are partially covered by the molding compound (118).The IC assembly (100) of claim 1, wherein the IC assembly (100) comprises an edge finger connector, the edge finger connector including conductive contacts on the second surface (106) of the first PCB (102).The IC assembly (100) of claim 10, wherein the edge finger connector includes conductive contacts on the first (112) surface of the second PCB (110).The IC package (100) of claim 1, wherein the IC package (100) is a solid state drive.The IC assembly (100) of claim 1, wherein a width of the IC assembly is 22 millimeters.The IC assembly (100) of claim 13, wherein a length of the IC assembly (100) is 42 millimeters.

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