HERMETICALLY-SEALED ELECTRICAL CIRCUIT APPARATUS

Information

  • Patent Application
  • 20100314149
  • Publication Number
    20100314149
  • Date Filed
    September 29, 2009
    15 years ago
  • Date Published
    December 16, 2010
    13 years ago
Abstract
Hermetically-sealed electrical circuit apparatus and methods for constructing such apparatus using one or more seal portions.
Description
BACKGROUND

The disclosure herein relates to hermetically-sealed electrical circuit apparatus, and further to fabrication methods for constructing such apparatus.


Electrical circuits (e.g., integrated circuits) include many types of active and passive devices (e.g., transistors, capacitors, resistors, etc.) that may be subject to damage from moisture (e.g., corrosion and functional changes to the system). For example, moisture may affect the operation and performance of circuitry, such as sensitive circuits used in implantable medical devices (e.g., sensor circuitry, pacing circuitry, timing circuitry, etc.).


Various attempts have previously been made to seal the interior of semiconductor device dies from moisture ingress. The bottom substrate in many semiconductor devices (e.g., silicon) effectively blocks moisture from entering the interior of the die from the bottom, but materials commonly employed in fabricating further layers above the substrate provide a path for moisture to enter from the top and/or sides of the die, e.g., after die separation. For example, certain commonly employed insulator materials such as silicon dioxide (SiO2) may be penetrated by moisture.


SUMMARY

The disclosure herein relates generally to hermetically-sealed electrical circuit apparatus, and methods of fabrication of such apparatus. For example, as described in one or more embodiments herein, semiconductor substrates and semiconductor fabrication techniques may be used to provide a hermetic enclosure around a circuit device (e.g., a die that includes circuitry).


One exemplary apparatus disclosed herein includes an electrical circuit apparatus. The electrical circuit apparatus includes a first portion, a second portion, at least one circuit, and one or more seal portions. The first portion includes a planar connection surface, a substrate provided from a wafer (e.g., the substrate includes a substrate surface opposite the planar connection surface) and at least one side surface extending between the substrate surface and the planar connection surface. The second portion includes a planar connection surface, a substrate provided from a wafer (e.g., the substrate comprises a substrate surface opposite the planar connection surface), and at least one side surface extending between the substrate surface and the planar connection surface. The planar connection surface of the first portion is bonded to the planar connection surface of the second portion to form an interface defining at least one interface edge about the perimeter of the interface between the planar connection surfaces of the first portion and the second portion. The at least one circuit device includes electrical circuitry. Further, the at least one circuit device is encompassed by at least portions of the first portion and the second portion. The one or more seal portions cover at least the at least one interface edge of the interface to restrict moisture from ingressing into the apparatus.


One exemplary method disclosed herein includes providing at least one electrical circuit apparatus. The method includes providing a first portion, providing a second portion, and providing at least one circuit device comprising electrical circuitry. The first portion includes a planar connection surface, a substrate provided from a wafer (e.g., the substrate comprises a substrate surface opposite the planar connection surface), and at least one side surface extending between the substrate surface and the planar connection surface. The second portion includes a planar connection surface, a substrate provided from a wafer (e.g., the substrate comprises a substrate surface opposite the planar connection surface), and at least one side surface extending between the substrate surface and the planar connection surface. The method further includes coupling the planar connection surface of the first portion to the planar connection surface of the second portion to form an interface defining at least one interface edge about the perimeter of the interface between the planar connection surfaces of the first portion and the second portion. After such coupling, the at least one circuit device is encompassed by at least portions of the first portion and the second portion. The method further includes providing one or more seal portions covering at least the at least one interface edge of the interface to restrict moisture from ingressing into the apparatus.


The above summary is not intended to describe each embodiment or every implementation of the present disclosure. A more complete understanding will become apparent and appreciated by referring to the following detailed description and claims taken in conjunction with the accompanying drawings.





BRIEF DESCRIPTION OF THE DRAWINGS


FIGS. 1A-1C are illustrative cross-sectional side views generally depicting a method for fabricating one exemplary embodiment of a hermetically-sealed electrical circuit apparatus.



FIG. 2A is an illustrative cross-sectional view of one exemplary embodiment of an electrical circuit apparatus such as generally shown in FIGS. 1A-1C.



FIG. 2B is an illustrative cross-sectional view of another exemplary embodiment of an electrical circuit apparatus such as generally shown in FIGS. 1A-1C.



FIG. 2C is an illustrative cross-sectional view of still another exemplary embodiment of an electrical circuit apparatus such as generally shown in FIGS. 1A-1C.



FIG. 2D is an illustrative cross-sectional view of yet still another exemplary embodiment of an electrical circuit apparatus such as generally shown in FIGS. 1A-1C.



FIG. 3A is an illustrative cross-sectional view of one exemplary embodiment of an electrical circuit apparatus, such as generally shown in FIGS. 1A-1C, including first and second portions having different sizes.



FIG. 3B is an illustrative cross-sectional view of another exemplary embodiment of an electrical circuit apparatus, such as generally shown in FIGS. 1A-1C, including first and second portions having different sizes.





DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the following detailed description of illustrative embodiments, reference is made to the accompanying figures of the thawing which form a part hereof, and in which are shown, by way of illustration, specific embodiments which may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from (e.g., still falling within) the scope of the disclosure presented hereby.


Exemplary apparatus, and methods of constructing such apparatus, shall be described with reference to FIGS. 1-3. It will be apparent to one skilled in the art that elements from one embodiment may be used in combination with elements of the other embodiments, and that the possible embodiments of such apparatus using combinations of features set forth herein is not limited to the specific embodiments shown in the Figures and/or described herein. Further, it will be recognized that the embodiments described herein may include many elements that are not necessarily shown to scale. Still further, it will be recognized that the size and shape of various elements herein may be modified but still fall within the scope of the present disclosure, although one or more shapes and/or sizes, or types of elements, may be advantageous over others.



FIGS. 1A-1C show illustrative cross-sectional views generally depicting a method for fabricating one exemplary embodiment of a hermetically-sealed electrical circuit apparatus 10 (see FIG. 1C) including at least one circuit device 90. The method may include providing a first portion 20 and a second portion 40.


Wafer scale fabrication techniques may be used to provide each of the first and second portions 20, 40. In one or more embodiments, each of the first portion 20 and the second portion 40 includes a substrate 22, 42, respectively, provided from or as a part of a wafer (e.g., a portion of any size and shape of substrate usable in wafer scale fabrication processes, such as a circular silicon wafer, a glass substrate, a plastic substrate, etc.). In other words, multiple portions may be fabricated on a wafer (e.g., the first portions on a first wafer and the second portions on a second wafer). As such, the fabrication of each of the portions may be initiated with use of a wafer substrate (e.g., a semiconductor, conductor, or insulator substrate wafer). In one or more embodiments, the wafer substrate is a doped semiconductor wafer substrate (e.g., doped to either a bulk n-type or p-type wafer), such as those used as the base substrate for microelectronic devices (e.g., substrates built in and over using one or more microfabrication process steps such as doping, ion implantation, etching, deposition of various materials, and photolithographic patterning processes). In one or more embodiments, the wafer is a silicon wafer. However, other available types of semiconductor wafers may be used, such as, for example, a gallium arsenide wafer, a germanium wafer, a silicon on insulator (SOI) wafer, etc. Further, for example, in one or more embodiments, the substrate may be formed of one or more materials other than semiconductor material, such as a glass substrate, wherein the substrate includes a metal film. In other words, for example, the first portion 20 may include a substrate 22 provided from or as a part of a wafer and the second portion 40 may include a substrate 42 provided from or as a part of a wafer.


As shown in FIGS. 1A-1C, the substrate 22 may include a substrate surface 23 located opposite a connection surface 25 of the first portion 20. The first portion 20 further includes one or more layers 24 formed on the substrate 22 terminating at the connection surface 25 (e.g., a planar connection surface, a connection surface orthogonal to the at least one side surface 21, etc.). Also, the first portion 20 includes at least one side surface 21 (e.g., one side surface, four side surfaces, etc.) extending between the substrate surface 23 and the connection surface 25 (e.g., defined by the substrate 22 and the one or more layers 24).


At least in one embodiment, the second portion 40 may only include a substrate (e.g., substrate 42). In the embodiment depicted, the second portion 40 is substantially similar to the first portion 20. For example, the substrate 42 may include a substrate surface 43 located opposite a connection surface 45 of the second portion 40. The second portion 40 may further include one or more layers 44 formed on the substrate 42 terminating at the connection surface 45 (e.g., a planar connection surface, a connection surface orthogonal to the at least one side surface 41). Also, the second portion 40 may include at least one side surface 41 (e.g., one side surface, four side surfaces, etc.) extending between the substrate surface 43 and the connection surface 45 (e.g., defined by the substrate 42 and the one or more layers 44).


At least in one embodiment, the connection surfaces 25, 45, which may be defined at least partly by one or more layers; may include oxide material. For example, such oxide material may be oxide material formed, deposited or grown as part of one or more processing steps (e.g., oxides such as borophosphosilicate glass, silicon dioxide, native oxide, etc.).


The apparatus 10 may include one or more circuit devices 90 (e.g., at least one circuit device 90) encompassed by (e.g., within, surrounded by, etc.) at least portions of the first and the second portions 20, 40. In at least one embodiment (as shown in FIGS. 1A-1C), the first portion 20 and/or the second portion 40 may be processed to form one or more circuit devices 90 by fabricating (e.g., using any known fabrication processes including deposition, patterning, and/or etching) the one or more circuit device 90 within the one or more layers 24, 44 fowled on the substrates 22, 42. In other words, the one or more circuit devices 90 may be formed as part of the one or more layers 24, 44 of the first and second portions 20, 40, respectively.


The first and second portions 20, 40 may further include one or more contact pads 30, 50, respectively, electrically coupled to the one or more circuit devices 90 using one or more interconnects 32, 52 (represented schematically with dashed lines) and located at the connection surfaces 25, 45. When the first portion 20 is assembled (e.g., bonded) with the second portion 40, the contact pads 30, 50 are electrically coupled to each other such that the one or more circuit devices 90 are electrically coupled to each other. Further, although not depicted, the apparatus 10 (e.g., the first portion 20 and/or the second portion 40) may include one or more additional interconnects extending between the circuit devices 90 and any other surface (e.g., outside surface) or any other location of the apparatus 10 for any purpose.


Further, although not depicted, one or both of the first and second portions 20, 40 (e.g., the one or more layers 24, 44) may define a cavity and at least one of the one or more circuit devices 90 may be located within the cavity. As used herein, the one or more circuit devices 90 may be any device or devices that include electrical circuitry that performs one or more functions (e.g., die containing circuitry). In such embodiments, the one or more circuit devices 90 may be directly electrically coupled to the one or more contacts pads 30, 50 without the use of interconnects (e.g., interconnects 32, 52). For example, at least in one embodiment, the second portion 40 defines a cavity extending into the connection surface 45. A circuit device 90 may be located within the cavity and electrically coupled to the contact pads 30 of the first portion 20.


The one or more circuit devices 90, the one or more interconnects 32, 52, and the one or more contact pads 30, 50 may be formed using standard microelectronic fabrication processing techniques (e.g., such as etching of materials, deposition of materials, and photolithographic patterning process steps, etc.). Further, various portions of first and second portions 20, 40 may be formed during the same or different processing steps. The present disclosure is not limited to any particular processing, or timing or order, of such process steps. However, some types of processing and order thereof may be beneficial over other types.


The method further includes bonding (e.g., oxide bonding, plasma-enhanced direct wafer bonding, etc.) the first portion 20 to the second portion 40 to form an interface 12 defining at least one interface edge 14 about the perimeter of the interface 12 (e.g., the interface 12 between the planar connection surfaces 25, 45 of the first and the second portions 20, 40) (see FIG. 1B). The interface 12 between the connection surfaces 25, 45, of the first portion 20 and the second portion 40 may be hermetic. As used herein, an interface that is hermetic is an interface that restricts (e.g., substantially limits, slows, prevents, etc.) moisture from passing, diffusing, pervading, infiltrating, and/or leaking through itself (e.g., the interface 12 may restrict moisture from passing, diffusing, pervading, infiltrating, and/or leaking through itself). As used herein, “moisture” may be defined as any material capable of ingressing into semiconductor devices. For example, moisture may include water, biological liquids, vapors, gases, etc.


In one or more embodiments, bonding the first and second portions 20, 40 together to assemble the apparatus 10 may be implemented using any wafer or die bonding process (e.g., bonding a wafer including the first portions with a wafer including the second portions, which also refers to the bonding of an individual die to a full wafer, an individual die to another individual die, etc.), such as chemical bonding processes (e.g., those using adhesion promoters, high temperature bonding processes, hydrogen bonding processes, plasma-enhanced bonding processes, oxide bonding processes, etc.). For example, use of plasma-enhanced bonding permits oxide surfaces (e.g., portions of the connection surfaces 25, 45 of the first and second portions 20, 40 including a dioxide material, such as silicon oxide or native oxide) to be bonded together.


Further, for example, in one or more embodiments, the connection surfaces 25, 45 may be each etched, polished, or planarized (e.g., using a chemical mechanical planarization or polishing) to expose any conductive portions thereof (e.g., the contact pads 30, 50 at connection surfaces 25, 45) to be exposed. For example, when the oxide portions and the conductive portions (e.g., contact pads 30) located at the connection surface 25 (e.g., a planar surface) are aligned with the oxide portions and the conductive portions (e.g., contact pads 50) located at the connection surface 45 (e.g., a planar surface), plasma-enhanced bonding may be performed. Further, plasma-enhanced bonding processes may form a bond between oxide portions of the connection surfaces 25, 45 of the first and second portions 20, 40 without the need for adhesives or other intermediate layers. For example, at least in one embodiment, the bonding at the interface 12 may be formed by driving off any existing water present between the connection surfaces 25, 45 and forming silicon-oxygen bonds throughout the structure such that a covalent bond is formed.


The method further includes providing one or more seal portions 60 at least covering the at least one interface edge 14 that, e.g., restricts moisture from entering the interface between the connection surfaces 25, 45 (e.g., planar connection surfaces) of the first and second portions 20, 40, respectively. As shown in FIG. 1C, the one or more seal portions 60 include a layer covering the entire exterior surface (e.g., the substrates surfaces 23, 43, the at least one side surfaces 41, 21, the interface 14, etc.). In at least one embodiment, the one or more seals portions 60 only cover a portion of the exterior surface of the apparatus 10 (e.g., one or more portions of one or both of the at least one side surface 21, 41 defined by either or both of the one or more layers 24, 44 of the first and the second portions 20, 40; one or more portions of one or both of the at least one side surface 21, 41 defined by either or both of the substrates 22, 42 of the first and the second portions 20, 40; one or more portions of the substrate surfaces 23, 43 of the first and the second portions 20, 40; etc.).


The one or more seal portions 60 may be provided by forming or depositing (e.g., physical deposition, chemical deposition, etc.) the one or more seal portions 60 as part of one or more processing steps (e.g., masking and depositing). For example, in at least one embodiment, the one or more seal portions 60 are provided by sputtering metals or polysilicon. Further, for example, in at least one embodiment, the one or more seal portions 60 are provided by chemical-vapor deposition.


The one or more seal portions 60 may include various materials such as, e.g., oxide materials, semiconductor materials, conductor materials, insulator materials, polysilicon, metals, phosphosilicate glass, borophosphosilicate glass, silicon nitride, tetraethyl orthosilicate, silox, etc. Further, such material of the one or more seal portions 60 may be biocompatible (e.g., such as for use in implantable medical devices). The one or more seal portions 60 may have a thickness of about 1 angstrom. Further, the one or more seal portions 60 may have a thickness of about 1 angstrom or more (in other words, at least about 1 angstrom), about 2 angstroms or more, about 5 angstroms or more, about 10 angstroms or more, about 50 angstroms or less, about 25 angstroms or less, about 10 angstroms or less, about 7 angstroms or less, about 5 angstroms or less, about 2 angstroms or less, or about 1 angstroms or less, etc. In at least one embodiment, the one or more seal portions 60 have a thickness that is thicker than the thickness of any material that may naturally form or grow on the first and second portions 20, 40 (e.g., native oxide).


In at least one embodiment, the one or more seal portions 60 may include one or more layers of the same or various materials formed in the same or different process. Further, each layer of the one or more layers forming the one or more seal portions 60 may have a thickness of at least about 1 angstrom. For example, the one or more seal portions 60 may include atomic layer deposition of dielectrics, sputtering of metals, chemical-vapor deposition of silicon nitride, etc


The apparatus 10 as shown in FIG. 1C may be utilized as a standalone package (e.g., apparatus 10 may not need any additional integrated circuit packaging or encapsulation). In at least one embodiment, however, one or more barrier layers (not shown) may be provided (e.g., formed) over the apparatus 10 after the one or more seal portions 60 have formed thereon. For example, the apparatus 10 may be encapsulated in silicone, medical adhesive, titanium, etc.


The process flow presented in FIGS. 1A-1C is only an exemplary method that may be used to implement the apparatus described herein and is not to be taken as limiting to the scope of the disclosure provided herein. Various modifications to the process and/or timing or order of the process steps may be made to the method while still providing the benefits of apparatus described herein.


Although not limited thereto, in one or more embodiments, the apparatus 10 is beneficial circuitry for packaging used in implantable medical devices. For example, the one or more circuit devices 90 of the apparatus 10 may be a part of an implantable medical device. Further, the apparatus 10 may be biocompatible. For example, the implantable medical device may be a device implantable in a body near a human heart. For example, the implanted medical device may be any implantable cardiac pacemaker, defibrillator, cardioverter-defibrillator, or pacemaker-cardioverter-defibrillator (PCD). Further, for example, the implantable medical device may be an implantable nerve stimulator or muscle stimulator, an implantable monitoring device (e.g., a hemodynamic monitoring device), a brain stimulator, a gastric stimulator, a drug pump, or any other implantable device that would benefit from moisture protection. Therefore, the apparatus 10 may find wide application in any form of implantable medical device. As such, any description herein making reference to any particular medical device is not to be taken as a limitation of the type of medical device which can benefit from and which can employ apparatus 10 as described herein.


Further, although the apparatus 10 may be beneficial for implantable medical devices, such structure is in no manner limited to such applications. For example, such testing structure may be beneficial for many different types of circuitry (e.g., whether for medical use or not, whether for an implantable medical device or not). For example, one or more types of circuits that may benefit from such testing structure may include circuits such as sensor circuits, pacing circuits, timing circuits, telemetry circuits, etc.



FIGS. 2A-2D and 3A-3B are illustrative cross-sectional views of exemplary embodiments of electrical circuit apparatus such as generally shown in FIGS. 1A-1C. Each embodiment depicted in each of FIGS. 2A-2D and 3A-3B utilizes many of the same components/portions, and as such, utilizes the same reference numbers in the description provided herein. However, each embodiment depicted in each of FIGS. 2A-2D and 3A-3B is constructed in different configurations.


The electrical circuit apparatus 210 may be similar to the electrical circuit apparatus 10 and components thereof described herein with reference to FIGS. 1A-1C. For example, electrical circuit apparatus 210 includes a first portion 220 (e.g., including a substrate 222, a substrate surface 223, one or more layers 224, a connection surface 225, at least one side surface 221, a circuit device 290, contact pads 230, and interconnects 232 (represented schematically with dashed lines)), a second portion 240 (e.g., including a substrate 242, a substrate surface 243, one or more layers 244, a connection surface 245, at least one side surface 241, a circuit device 290, contact pads 250, and interconnects 252 (represented schematically with dashed lines)), an interface 212 defining at least one interface edge 214 about the perimeter of the interface 212, and a one or more seal portions 260. As such, for simplicity, further description on some of the details of the electrical circuit apparatus 210 shall not be provided.


The one or more seal portions 260 are located in various locations on the exemplary electrical circuit apparatus 210 depicted in FIGS. 2A-2D. For example, the one or more seal portions 260 cover a portion of the at least one side surface 221 of the first portion 220 and at least a portion of the at least one side surface 241 of the second portion 240 of the electrical circuit apparatus 210 in FIG. 2A. More specifically, the at least one interface edge 214 and portions of the side surfaces 221, 241 defined by portions of both of the one or more layers 224, 244 are covered by the one or more seal portions 260 such that the one or more seal portions 260 restrict moisture ingress (e.g., movement of moisture) into the electrical circuit device 290 (e.g., through the interface 212), e.g., to protect the circuit devices 290. The one or more seal portions 260 may extend around the entire interface edge 214 or one or more portions of interface edge 214 (e.g., one or more sides so as to restrict moisture ingress from particular directions).


Further, the apparatus 210 depicted in FIG. 2A includes interconnects 232, 252 extending within the one or more layers 224, 244, respectively, between the circuit devices 290 and the contact pads 230, 250. The contact pads 230, 250 are located within the one or more layers 224, 244 proximate the respective side surfaces 221, 241 without being covered by the one or more seal portions 260 such that, e.g., they may electrically connected to any other device. Although only two contact pads 230, 250 and two interconnects 232, 252 are depicted in FIG. 2A, the electrical circuit apparatus 210 may include more or less than two contact pads and two interconnects electrically coupled to the circuit devices 290. As a result of interconnects 232, 252 and contact pads 230, 250, the circuit devices 290 may be in electrical communication with a device located outside of the electrical circuit apparatus 210 by electrically coupling such device to the contact pads 230, 250. Further, the circuit devices 290 of the first and second portions 220, 240 may be electrically coupled to each other by the use of interconnects (not shown) similar to the electrical circuit devices 90 depicted in FIGS. 1A-1C.


The formation of interconnects 232, 252 and the contact pads 230, 250 may be formed using standard microelectronic fabrication processing techniques (e.g., such as etching of materials, deposition of materials, photolithographic patterning process steps, etc.). Further, interconnects 232, 252 may be formed of various structures including, e.g., stacked vias, through-silicon vias, metal layers, etc. Various portions of first and second portions 220, 240 may be formed during the same or different processing steps. For example, a portion of an interconnect 232 may be formed within a layer of the one or more layers 224 during formation of device 290. Still further, for example, process steps to form interconnects 232, 252 may be completely separate therefrom, such as in the formation of a through-silicon via after other layer processing is completed. The present disclosure is not limited to any particular processing, or timing or order, of such process steps. However, some types of processing and order thereof may be beneficial over other types.


Still further, in one or more embodiments, the first and second portions 220, 240 may not include interconnects or vias connecting the circuit devices to contact pads on the outside of the apparatus 210. For example, in at least one embodiment, the apparatus 210 may include various apparatus and/or structures to wirelessly communicate to other devices/apparatus outside of apparatus 210.


One or more seal portions 260 cover a larger portion of the side surfaces 221, 241 of the electrical circuit apparatus 210 in FIG. 2B than in FIG. 2A. More specifically, the interface edge 214, portions of side surfaces 221, 241 defined by the one or more layers 224, 244, and a portion of the substrates 222, 242 are covered by the one or more seal portions 260 such that one or more seal portions 260 restrict moisture ingress (e.g., movement of moisture) into the electrical circuit apparatus 210 (e.g., through the interface 212, one or more layers 224, 244, etc.), e.g., to protect the circuit devices 290.


The apparatus 210 depicted in FIG. 2B includes interconnects 232, 237, 252 extending between the circuit devices 290 and the contact pads 230, 250. In this embodiment, the contact pads 230, 250 are located proximate the substrate surface 243 of the second portion 240. The interconnect 232 extends through the one or more layers 224 of the first portion 220 to a contact pad 234. The contact pad 234 is electrically coupled to contact pad 236 when the first portion 220 is coupled to the second portion 240. The contact pad 236 is electrically coupled to interconnect 237, which extends through the second portion 240 (e.g., the one or more layers 244 and the substrate 242) to the contact pad 230 thereby electrically coupling the contact pad 230 and the circuit device 290 of the first portion 220. The interconnects described herein may also use a similar connection (using contact pads, etc.) between the one or more layers and substrate of a respective portion. Further, interconnect 252 extends through the one or more layers 244 and the substrate 242 and is electrically coupled to contact pad 250. Although only contact pads 230, 250 and interconnects 232, 237, 252 are depicted in FIG. 2B, the electrical circuit apparatus 210 may include more than two contact pads and/or more than three interconnects electrically coupled to the circuit devices 290.


Further, for example, one or more seal portions 260 may cover the substrate surface 243 of the second portion 240 and a portion of the side surfaces 221, 241 of the electrical circuit apparatus 210 as shown in FIG. 2C. More specifically, the interface edge 214, the side surface 221 defined by the substrate 242, the side surfaces 221, 241 defined by the one or more layers 244, the side surface 221 defined by a portion of the substrate 222, and the substrate surface 243 are covered by the one or more seal portion 260 such that one or more seal portions 260 restrict moisture ingress (e.g., movement of moisture) into the electrical circuit apparatus 210 (e.g., through the interface 212, through the one or more layers 224, 244, etc.) to, e.g., protect the circuit devices 290.


The apparatus 210 depicted in FIG. 2C includes interconnects 232, 252 extending between the circuit devices 290 and the contact pads 230, 250. In this embodiment, the contact pads 230, 250 are located proximate the substrate surface 223 of the first portion 220. The interconnect 252 extends through the one or more layers 244 of the second portion 240 and through the one or more layers 224 and substrate 222 of the first portion 220 to the contact pad 250 (e.g., electrically coupled to the contact pad 250). Although not depicted in FIG. 2C, the interconnect 252 may include multiple portions and/or contact pads (e.g., contact pads located proximate each of the connection surfaces 225, 245 so as to complete the interconnect 252 when the first portion 220 is bonded to the second portion 240 similar to contact pads 234, 236 shown in FIG. 2B). Further, interconnect 232 extends through the one or more layers 224 and the substrate 222 to contact pad 230 (e.g., electrically coupled to the contact pad 230). Although only contact pads 230, 250 and interconnects 232, 252 are depicted in FIG. 2C, the electrical circuit apparatus 210 may include more than two contact pads and/or more than two interconnects electrically coupled to the circuit devices 290.


Still further, for example, one or more seal portions 260 may cover at least a portion of the substrate surface 243 of the second portion 240 and a portion of the side surfaces 221, 241 of the electrical circuit apparatus 210 as shown in FIG. 2D. More specifically, the interface edge 214, the side surfaces 221, 241 defined by the one or more layers 224, 244, the side surface 221 defined by least a portion of the substrate 222, the surface 241 defined by the substrate 242, and at least a portion of the substrate surface 243 are covered such that one or more seal portions 260 restrict moisture ingress (e.g., movement of moisture) into the electrical circuit apparatus 210 (e.g., through the interface 212, through one or more layers 224, 244, etc.), e.g., to protect the circuit devices 290.


The apparatus 210 depicted in FIG. 2D includes interconnects 232, 252 extending between the circuit devices 290 and the contact pads 230, 250 in a similar manner to that shown in FIG. 2C but to surface 243 instead of to surface 223.


The apparatus 210 depicted in FIGS. 3A-3B includes first portions 220 that are larger than the second portions 240 (e.g., the connection surface 225 of the first portion 220 defines a larger area than the connection surface 245 of the second portion 240). In at least one embodiment, the second portion 240 when bonded to the first portion 220 is centered within the area defined by the connection surface 225 of the first portion 220. The first portion 220 and the second portion 240 may be any size relative to each other so as to provide suitable functionality to the apparatus 210 (e.g., to provide contact pads on various locations of the apparatus 210 for electrically coupling the apparatus 210 to various devices, to reduce the size and/or shape of the apparatus 210, to reduce the amount of material used to form the apparatus 210, etc.).


The apparatus 210 depicted in FIGS. 3A-3B, however, differ from each other in that at least the angle and/or shape of their respective side surfaces 241 of the second portions 240 differ. For example, the second portion 240 depicted in FIG. 3A includes at least one side surface 241 that is substantially perpendicular to the connection surface 245 such that the area of the substrate surface 243 is about equal to the area of the connection surface 245. The second portion 240 depicted in FIG. 3B includes at least one side surface 241 that is not perpendicular but rather is less than 90 degrees (e.g., the angle alpha between the at least one side surface 241 and the connection surface 254 may be about 89 degrees, 85 degrees, 80 degrees, 70 degrees, 60 degrees, 50 degrees, 45 degrees, 40 degrees, 30 degrees, etc.) to the connection surface 245 such that the area of the substrate surface 243 is smaller than the area of the connection surface 245.


The one or more seal portions 260 are located in substantially the same locations on the exemplary electrical circuit apparatus 210 depicted in FIGS. 3A-3B. For example, the one or more seal portions 260 cover the at least one side surface 241 defined by the one or more layers 244 and substrate 242 of the second portion 240, at least a portion of the substrate surface 243 of the second portion 240, and at least a portion of the connection surface 225 of the first portion 220 of the electrical circuit apparatus 210. Further, the at least one interface edge 214 between the connection surface 225 of the first portion 220 and the connection surface 245 of the second portion 240 is covered such that the one or more seal portions 260 restrict moisture ingress (e.g., movement of moisture) into the electrical circuit device 290 (e.g., through the interface 212, through the one or more layers 224, 244, etc.), e.g., to protect the circuit devices 290.


Further, the apparatus 210 depicted in FIGS. 3A-3B includes interconnects 232, 252 extending between the circuit devices 290 and the contact pads 230, 250. The contact pads 230, 250 are located proximate the substrate surface 243 of the second portion and are not covered by the one or more seal portions 260 such that, e.g., they may be electrically connected to any other device. Interconnect 232 extends through the one or more layers 224 of the first portion 220 and the one or more layers 244 and substrate 242 of the second portion 240. Further, interconnect 252 extends through the one or more layers 244 and substrate 242 of the second portion 240. Although not depicted in FIGS. 3A-3B, the interconnect 232 may include multiple portions and/or contact pads (e.g., contact pads located proximate each of the connection surfaces 225, 245 so as to complete the interconnect 232 when the first portion 220 is bonded to the second portion 240 similar to contact pads 234, 236 shown in FIG. 2B). Further, although only two contact pads 230, 250 and two interconnects 232, 252 are depicted in FIGS. 3A-3B, the electrical circuit apparatus 210 may include more than two contact pads and/or interconnects electrically coupled to the circuit devices 290. As a result of these contact pads and interconnects, the circuit devices 290 may be in electrical communication with a device located outside of the electrical circuit apparatus 210 by connecting such device to the contact pads 230, 250. Further, the circuit devices 290 of the first and second portions 220, 240 may be electrically coupled to each other by the use of interconnects (not shown) similar to the electrical circuit device 10 depicted in FIGS. 1A-1C.


Any features, components, and/or properties of any of the embodiments described herein may be incorporated into any other embodiment(s) described herein.


All patents, patent documents, and references cited herein are incorporated in their entirety as if each were incorporated separately. This disclosure has been provided with reference to illustrative embodiments and is not meant to be construed in a limiting sense. As described previously, one skilled in the art will recognize that other various illustrative applications may use the techniques as described herein to take advantage of the beneficial characteristics of the apparatus and methods described herein. Various modifications of the illustrative embodiments, as well as additional embodiments of the disclosure, will be apparent upon reference to this description.

Claims
  • 1. An electrical circuit apparatus comprising: a first portion comprising: a planar connection surface,a substrate provided from a wafer, wherein the substrate comprises a substrate surface opposite the planar connection surface, andat least one side surface extending between the substrate surface and the planar connection surface;a second portion comprising: a planar connection surface,a substrate provided from a wafer, wherein the substrate comprises a substrate surface opposite the planar connection surface, andat least one side surface extending between the substrate surface and the planar connection surface, wherein the planar connection surface of the first portion is bonded to the planar connection surface of the second portion to foam an interface defining at least one interface edge about the perimeter of the interface between the planar connection surfaces of the first portion and the second portion;at least one circuit device comprising electrical circuitry, wherein the at least one circuit device is encompassed by at least portions of the first portion and the second portion; andone or more seal portions covering at least the at least one interface edge of the interface to restrict moisture from ingressing into the apparatus.
  • 2. The apparatus of claim 1, wherein the one or more seal portions comprise deposited material.
  • 3. The apparatus of claim 1, wherein the one or more seal portions comprise a thickness of at least about 1 angstrom.
  • 4. The apparatus of claim 1, wherein the one or more seal portions comprise oxide material.
  • 5. The apparatus of claim 1, wherein the one or more seal portions cover at least a portion of the at least one side surface of the first portion and the at least one side surface of the second portion to restrict moisture from ingressing into the apparatus.
  • 6. The apparatus of claim 1, wherein at least one of the first portion and the second portion further comprises one or more layers formed on the substrate thereof terminating at the connection surface thereof and defining a portion of the at least one side surface thereof, wherein the one or more seal portions cover the portion of the at least one side surface defined by the one or more layers to restrict moisture from ingressing into the apparatus.
  • 7. The apparatus of claim 1, wherein the one or more seal portions at least partially cover the substrate surface of the first portion, the substrate surface of the second portion, the at least one side surface of the first portion, and the at least one side surface of the second portion to restrict moisture from ingressing into the apparatus.
  • 8. The apparatus of claim 1, wherein the connection surface of the first portion defines a larger area than the connection surface of the second portion.
  • 9. The apparatus of claim 1, wherein the substrate of the first portion and the substrate of the second portion each comprise semiconductor substrates.
  • 10. The apparatus of claim 1, wherein the at least one circuit device forms a part of an implantable medical device.
  • 11. The apparatus of claim 1, wherein the first portion further comprises one or more layers formed on the substrate terminating at the connection surface, wherein the one or more layers of the first portion comprise a circuit device of the at least one circuit device.
  • 12. The apparatus of claim 11, wherein the one or more layers of the first portion further comprise contact pads electrically coupled to the circuit device and located at the connection surface, and wherein second portion further comprises one or more layers formed on the substrate terminating at the connection surface, wherein the one or more layers of the second portion further comprise a circuit device of the at least one circuit device and contact pads electrically coupled to the circuit device and located at the connection surface, wherein the contact pads of the first portion are electrically coupled to the contact pads of the second portion to electrically couple the circuit device of the first portion to the circuit device of the second portion.
  • 13. The apparatus of claim 1, wherein at least one of the first portion and the second portion defines a cavity, wherein a circuit device of the at least one circuit device is located within the cavity.
  • 14. The apparatus of claim 1, wherein the apparatus further comprises: one or more interconnect vias formed in at least one of the first portion and the second portion and terminating at one or more surface contacts at the substrate surface, the connection surface, or the at least one side surface of at least one of the first and second portions; andat least one electrical interconnect extending from the at least one circuit device to at least one of the one or more interconnect vias.
  • 15. The apparatus of claim 1, wherein the connection surface of the first portion is plasma-enhanced bonded to the connection surface of the second portion.
  • 16. A method of providing at least one electrical circuit apparatus, wherein the method comprises: providing a first portion, wherein the first portion comprises: a planar connection surface,a substrate provided from a wafer, wherein the substrate comprises a substrate surface opposite the planar connection surface, andat least one side surface extending between the substrate surface and the planar connection surface,providing a second portion, wherein the second portion comprises: a planar connection surface,a substrate provided from a wafer, wherein the substrate comprises a substrate surface opposite the planar connection surface, andat least one side surface extending between the substrate surface and the planar connection surface,providing at least one circuit device comprising electrical circuitry;coupling the planar connection surface of the first portion to the planar connection surface of the second portion to form an interface defining at least one interface edge about the perimeter of the interface between the planar connection surfaces of the first portion and the second portion, wherein the at least one circuit device is encompassed by at least portions of the first portion and the second portion; andproviding one or more seal portions covering at least the at least one interface edge of the interface to restrict moisture from ingressing into the apparatus.
  • 17. The method of claim 16, wherein providing one or more seal portions comprising depositing one or more seal portions.
  • 18. The method of claim 16, wherein the one or more seal portions comprise a thickness of at least about 1 angstrom.
  • 19. The method of claim 16, wherein the one or more seal portions comprise oxide material.
  • 20. The method of claim 16, wherein coupling the planar connection surface of the first portion to the planar connection surface of the second portion comprises oxide bonding the planar connection surface of the first portion to the planar connection surface of the second portion.
  • 21. The method of claim 16, wherein coupling the planar connection surface of the first portion to the planar connection surface of the second portion comprises plasma-enhanced bonding the planar connection surface of the first portion to the planar connection surface of the second portion.
  • 22. The method of claim 16, providing the first portion comprises providing one or more layers formed on the substrate thereof terminating at the connection surface thereof and defining a portion of the at least one side surface thereof, wherein the one or more seal portions cover at least the portion of the at least one side surface defined by the one or more layers to restrict moisture from ingressing into the apparatus to restrict moisture from ingressing into the apparatus.
  • 23. The method of claim 22, providing at least one circuit device comprises forming the at least one circuit within the one or more layers formed on the substrate of the first portion.
  • 24. The method of claim 16, wherein the one or more seal portions at least partially cover each of the substrate surfaces and completely cover the at least one side surfaces of the first portion and the second portion to restrict moisture from ingressing into the apparatus.
  • 25. The method of claim 16, wherein the substrate of the first portion and the substrate of the second portion each comprise semiconductor substrates.
  • 26. The method of claim 16, wherein the at least one circuit device forms a part of an implantable medical device.
  • 27. The method of claim 16, wherein at least one of the first portion and the second portion defines a cavity, wherein a circuit device of the at least one circuit device is located within the cavity.
  • 28. The method of claim 16, wherein the apparatus further comprises: one or more interconnect vias formed in at least one of the first portion and the second portion and terminating at one or more surface contacts at the substrate surface, the connection surface, or the at least one side surface of at least one of the first and second portions; andat least one electrical interconnect extending from the at least one circuit device to at least one of the one or more interconnect vias.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser. No. 61/185,881 filed 10 Jun. 2009, entitled “FARADAY CAGE FOR CIRCUITRY USING SUBSTRATES,” U.S. Provisional Application Ser. No. 61/229,867 filed 30 Jul. 2009, entitled “APPARATUS FOR RESTRICTING MOISTURE INGRESS,” U.S. Provisional Application Ser. No. 61/229,869 filed 30 Jul. 2009, entitled “HERMETICITY TESTING,” and U.S. Provisional Application Ser. No. 61/235,745 filed 21 Aug. 2009, entitled “HERMETICALLY-SEALED ELECTRICAL CIRCUIT APPARATUS,” all of which are incorporated herein by reference in their respective entireties.

Provisional Applications (4)
Number Date Country
61235745 Aug 2009 US
61229869 Jul 2009 US
61229867 Jul 2009 US
61185881 Jun 2009 US