Very low magnetic field integrated circuit

[0002] The present invention relates to integrated circuit device packages. It finds particular application in conjunction with radio-frequency shielded integrated circuit device packages and will be described with particular reference thereto. It will be appreciated, however, that the invention is also amenable to other like applications.

[0003] Integrated circuit devices and/or semiconductor devices find use in a variety of high-density electronics applications. The devices are typically protected from the external environment by transfer molding a thermoset or thermoplastic resin package around the device. The package provides protection from dust, humidity, and other environmental factors that harm and/or destroy delicate circuitry within the device. However, such packages do not prevent various forms of radiation (e.g., radio-frequency (“RF”) signals, electromagnetic signals (“EM”), etc.), which are produced by the integrated circuit device, escaping from the package. RF and EM signals, for example, often interfere with other nearby integrated circuit and/or semiconductor devices.

[0004] One conventional shielding system is generally characterized by a ferrite material secured to an external surface (e.g., a top surface) of an integrated circuit using an adhesive. The shield acts to reduce the amount of radiation that escapes from the device to which it is attached, thereby avoiding interference with other nearby electronic devices. Also, the shield acts to reduce radiation produced by other nearby devices from interfering with the device to which it is attached. One drawback to this conventional shielding system, however, is that each integrated circuit device in a system often times must be shielded. Furthermore, since the ferrite shielding material is not incorporated into each integrated circuit and/or semiconductor device during the manufacturing process, end-users of the devices often times must manually secure shields to each of the devices within a system. Such steps may be both tedious and time consuming. Also, the shields may represent an unexpected cost to the end-user.

[0005] The present invention provides a new and improved apparatus and method which overcomes the above-referenced problems and others.

[0006] An integrated circuit includes a non-metallic casing forming a hollow cavity. At least one first electrical connector extends through a first face of the non-metallic casing. At least one electronic device is secured within the hollow cavity and is capable of producing a radio-frequency energy. At least one second electrical connector electrically connects the at least one electronic device to the at least one first electrical connector. A first shielding material, which is disposed within the hollow cavity between the at least one electronic device and a second face of the non-metallic enclosure, reduces the radio-frequency energy emitted from the non-metallic casing.

[0007] One advantage of the present invention is that the amount of radio-frequency and electromagnetic signals emitted from the integrated circuit device is reduced without completely enclosing the integrated circuit device.

[0008] Another advantage of the present invention is that the amount of radio-frequency and electromagnetic signals emitted from the integrated circuit device is reduced without the use of external shielding devices.

[0009] Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.

[0010] The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating a preferred embodiment and are not to be construed as limiting the invention.

[0011] FIG. 1 illustrates a cross-sectional view of a very low magnetic field integrated circuit package according to the present invention;

[0012] FIG. 2 illustrates a second embodiment of the very low magnetic field integrated circuit package according to the present invention;

[0013] FIG. 3 illustrates a third embodiment of the very low magnetic field integrated circuit package according to the present invention; and

[0014] FIG. 4 illustrates steps for manufacturing the very low magnetic field integrated circuit package according to the present invention.

[0015] With reference to FIG. 1, an integrated electronic device package 10 includes an enclosing structure 12 that defines a hollow cavity 14. Preferably, the enclosing structure 12 is not electrically conductive and includes, for example, a plastic material. However, it is to be understood that other materials are also contemplated for the enclosing structure 12. As will be described below the enclosing structure 12 includes two (2) pieces 12a,12bof the non-conductive material that are secured together.

[0016] A substrate 16 is secured within the hollow cavity 14. Electrical connectors 18, which provide external electrical connections to a circuit board (not shown), are secured in and protrude through a first face 22 of the enclosing structure 12. An electronic device 24 is mechanically secured to the substrate 16 and electrically connected to the electrical connectors 18. In the preferred embodiment, the electronic device 24 is an integrated circuit chip. However, it is also contemplated that the electronic device be a semiconductor device. Preferably, the electronic device 24 is electrically connected to the electrical connectors 18 using respective metal solder connection wires 26. However, other types of electrical connections are also contemplated. During use, radiation (e.g., radio-frequency signals and/or electromagnetic signals) are emitted from the electronic device 24.

[0017] A first shielding material 28, which acts as a shield for at least some types of the radiation (e.g., radio-frequency signals and/or electromagnetic signals) produced by the electronic device 24, is secured within the enclosing structure 12. The first shielding material 28 is positioned between the electronic device 24 and a second face 32 of the enclosing structure 12. Preferably, an insulator 34 (e.g., an air gap or a non-conductive sheet such as plastic) exists between the first shielding material 28 and the electronic device 24. The insulator 34 prevents the electronic device 24 from being scratched and/or shorted-out by the first shielding material 28.

[0018] In the preferred embodiment, the first shielding material 28 includes a radio-frequency absorbing material (e.g., a ferrite material). The radio-frequency absorbing material absorbs at least a portion of the radio-frequency signals and/or electromagnetic signals produced by the electronic device 24. More specifically, the radio-frequency absorbing material 28 receives at least a portion of the radiation produced by the electronic device 24 and converts the radiation to a second form of energy (e.g., heat). The second form of energy does not interfere with electrical operations of other nearby integrated electronic device packages, which may be located on the same circuit board (not shown). Therefore, the amount of radio-frequency energy emitted from the integrated electronic device package 10 is reduced by the amount of radio-frequency energy absorbed by the first shielding material 28.

[0019] FIG. 2 illustrates a second embodiment of the present invention. For ease of understanding this embodiment of the present invention, like components are designated by like numerals with a primed (′) suffix and new components are designated by new numerals.

[0020] The integrated electronic device package 10′ illustrated in FIG. 2 shows a first shielding material 42 including a metal. The metal of the first shielding material 42 receives at least a portion of the radio-frequency energy and/or electromagnetic signals produced by the electronic device 24′. An electrical connection 44 (e.g., a metal wire) electrically connects the first shielding material 42 to an electrical ground 46. Substantially all of the radio-frequency energy received by the first shielding material 42 is transferred to the ground 46 via the electrical connection 44. The ground 46 absorbs substantially all of the transferred radio-frequency energy. Therefore, the amount of radio-frequency energy emitted from the integrated electronic device package 10′ is reduced by the amount of radio-frequency energy received by the first shielding material 42.

[0021] FIG. 3 illustrates a third embodiment of the present invention. For ease of understanding this embodiment of the present invention, like components are designated by like numerals with a primed (″) suffix and new components are designated by new numerals.

[0022] The integrated electronic device package 10″ illustrated in FIG. 3 includes first and second shielding materials 28″, 62 secured within the hollow cavity 14″. As in the embodiment shown in FIG. 1, the first shielding material 28″ is disposed between the electronic device 24″ and the first face 22″ of the enclosing structure 12″. Preferably, for the reasons discussed above, respective insulators 34″, 64 separate the first and second shielding materials 28″, 62 from the electronic device 24″.

[0023] The first shielding material 28″ includes the ferrite material. The second shielding material 62 includes the metal material. An electrical connection 66 (e.g., a metal wire) electrically connects the second shielding material 62 to the ground 46″. As discussed above, the ferrite material of the first shielding material 28″ converts at least a portion of the RF radiation signals emitted from the integrated electronic device package 24″ to a second form of energy, such as heat. Furthermore, as discussed above, the metal material of the second shielding material 62 receives at least a portion of the radio-frequency energy produced by the electronic device 24″. Substantially all of the radio-frequency energy received by the second shielding material 62 is transferred to the ground 46″ via the second shielding material 62 and the electrical connection 66. The ground 46″ absorbs substantially all of the transferred radio-frequency energy. In this manner, the amount of radio-frequency energy emitted from the integrated electronic device package 24″ is reduced by the amount of radio-frequency energy received by the first and second shielding materials 28″, 62, respectively.

[0024] Although the first and second shielding materials 28″, 62 illustrated in FIG. 3 include a ferrite material and at least one metal material, respectively, other combinations of materials in the first and second shielding materials are also contemplated. For example, the first shielding material may include the metal material, in which case an electrical connection would connect the first shielding material to the ground. Similarly, the second shielding material may include the ferrite material, in which case no electrical connection would connect the second shielding material to the ground. Furthermore, both the first and second shielding materials may include the ferrite material, in which case neither of the first and second shielding materials would be connected to the ground. Alternatively, both the first and second shielding materials may include the metal material, in which case both the first and second shielding materials would be connected to the ground. In this case, it is also contemplated that the first and second shielding materials include different metal materials.

[0025] With reference to FIGS. 1 and 4, the integrated electronic device package 10 is fabricated according to the method described below.

[0026] The electrical connectors 18 are extended through the first piece 12bof the enclosing structure 12 in a step 80. T he electronic device 24 is electrically connected to the electrical connectors 18 in a step 82. The electronic device 24 is secured to the first piece 12bof the enclosing structure 12 in a step 84. The first shielding material 28 is secured to the second piece 12aof the enclosing structure 12 in a step 86. Optionally, the non-conductive sheet 34 is applied over the electronic device 24 and the metal solder connection wires 26 in a step 88.

[0027] The hollow cavity 14 is formed by securing the first and second pieces 12b,12a,respectively, of the enclosing structure 12 together in a step 90. Securing the first and second pieces 12b,12a,respectively, causes the electronic device 24 and the first shielding material 28 to be enclosed within the hollow cavity 14. Also, the electronic device 24 and the first shielding material 28 are substantially surrounded by the first and second pieces 12b,12a,respectively, of the enclosing structure 12. Furthermore, the electronic device 24 is disposed between the first piece 12bof the enclosing structure 12 and the first shielding material 28. As discussed above, the insulator 34 prevents the electronic device 24 from contacting the first shielding material 28.

[0028] With reference to FIGS. 3 and 4, the second shielding material 62 is secured to the first piece 12b″ of the enclosing structure 12″ in a step 92. The step 92 occurs after the step 80 of extending the electrical connectors 18″ through the first piece 12b″ of the enclosing structure 12″ is. The second shielding material 62 is disposed within the hollow cavity 14″ and between the electronic device 24″ and the first piece 12b″ of the enclosing structure 12. As discussed above, the insulator 64 (e.g., an air gap or a non-conductive sheet such as plastic) prevents the electronic device 24″ from contacting the second shielding material 62.

[0029] The invention has been described with reference to the preferred embodiment. obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.