Abstract:
An improved memory module and method of manufacture are presented. The memory module takes on the same outer dimensions as conventional memory cards. The memory module includes an integrated circuit and a conductor encased within molded resin. The conductor can be taken from a tape or a lead frame, and can include bumps or wires extending from the conductor to corresponding bonding pads on the integrated circuit. The bonded integrated circuit can thereafter be placed within a cavity formed inside a mold housing, where resin may be injected to form the memory module. The conductor can also be shaped so as to extend on multiple planes from the connection point on or near the bonding pad to an edge connector residing near one edge only of the memory module. The conductor thereby serves as an integrated signal carrier which receives connection to the integrated circuit and provides slide-in, releasable coupling to a receptor normally designed to receive conventional memory cards. The portion of the conductor that suffices as the edge connector is configured as a pad that has an outer surface substantially flush with an outer surface of the memory module for abutment against planar conductive elements within the receptor.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to integrated circuit packaging and, more particularly, to semiconductor memory encased within a molded resin to form a memory module having edge connectors aligned substantially within a row near the edge of the module. The edge connectors are configured as substantially planar pads extending along an outer surface of the module, where the outer, exposed surface of the edge connectors frictionally contact against an outer surface of corresponding pads arranged within a receptor. The receptor thereby receives the memory module dimensioned according to standards adopted by compact flash card, smart media card, flash path card, multimedia card and secure digital card manufacturers, including the standardized dimensions offered by JEIDA and PCMCIA, for example.  
           [0003]    2. Description of the Related Art  
           [0004]    The following descriptions and examples are not admitted to be prior art by virtue of their inclusion within this section.  
           [0005]    An electronic system is typically known as any device that can receive, transmit, and process electronic signals. Examples of popular electronic systems include the personal computer, personal digital assistant (PDA), digital camera, or any other electronic-based appliance used in a consumer setting. A commonality among all electronic systems is that they employ an interconnection of one or more circuits. Depending on the amount of integration, the circuits can be formed on a single monolithic substrate, often a silicon substrate, henceforth referred to as an integrated circuit.  
           [0006]    Typical electronic systems use one or more integrated circuits connected to each other by conductors. Thus, circuits within one integrated circuit can communicate with circuits within another integrated circuit. In order to protect the functionality of the circuits, each integrated circuit is often placed in a package which seals the integrated circuit from the environment. In addition to it being used to protect an integrated circuit, a package can also help distribute signals sent to and from the integrated circuit and, depending on the materials used, the package may also help dissipate heat that occurs during operation of the integrated circuit.  
           [0007]    There are numerous types of integrated circuit packages, basically categorized as either ceramic packages or plastic packages. Ceramic packages surround the encased integrated circuit with air, while plastic packages generally employ a resin that fills the space between the integrated circuit and the surrounding package. Plastic packages are often less expensive than ceramic packages. Regardless of whether ceramic or plastic is used, there are numerous package configurations and lead arrangements extending from the package. The leads serve to communicate signals to and from the integrated circuit and, thus, are electrically connected to corresponding bonding pads on the integrated circuit in one of possibly three ways: wire bonds, Tape-Automated Bonding (TAB), or flip-chip. Each of these arrangements are relatively well-known and are used in differing applications based on cost constraints and the density of the integrated circuit bonding pads.  
           [0008]    Once the integrated circuit is bonded to the leads and a package is formed about the integrated circuit, the matter of connecting one packaged integrated circuit to another packaged integrated circuit generally involves a printed circuit board or “card.” A card is a rigid, substantially planar backbone element that employs one or more layers of trace conductors separated by a dielectric. The trace conductors extend along one ore more of the conductive layers and, through vias, connect leads of one integrated circuit to leads of another integrated circuit. The printed circuit board can have plated-through holes to accommodate downward extending leads of a packaged integrated circuit, or can simply have a square or rectangular pad on which planar surfaces of the packaged integrated circuit leads can be surface-mounted. The card serves not only to interconnect signals between integrated circuits, but also provides mechanical support for multiple integrated circuits arranged within a chassis of the electronic system. The card thereby suffices to arrange the bonded integrated circuits a spaced distance from each other within the confines of the chassis.  
           [0009]    There are numerous ways in which to configure a card and the integrated circuits bonded to that card. For example, FIG. 1 illustrates a memory card  10  with edge connectors  12 . Edge connectors  12  can be arranged on the backside surface of card  10  near a forward-leading edge  14  of card  10 . According to this example, edge  14  can be inserted through a slot  16  extending through a chassis  18  of an electronic system  20 .  
           [0010]    Memory card  10  can, therefore, be inserted into a receptor  22  that is electrically connected to, for example, another card  24 . Like card  10 , card  24  may also contain printed conductors and one or more integrated circuits  26  interconnected with each other on a surface of card  24 . However, distinguishable from card  24 , card  10  is used for a specific purpose that can be universally applied to an electronic system, and is obtainable from numerous vendors in the memory technology sector. Card  10  is therefore a memory card, and utilizes edge connectors  12  that can be frictionally engaged with conductive elements  28  arranged within receptor  22 . Connectors  12  are designed to be releasibly inserted into receptor  22 .  
           [0011]    Shown in FIG. 2 is card  10  illustrated in partial breakaway. Card  10  is shown having one or more integrated circuits  30  connected to each other and to edge conductors  12  by trace conductors  32 . A memory card preferably uses some form of memory array. A popular memory array involves an array of non-volatile storage elements. The non-volatile storage elements are preferably configured on a single monolithic silicon substrate, to form a non-volatile memory integrated circuit  30   b . Along with circuit  30   b  is a memory controller  30   a.  In addition to integrated circuits  30 , card  10  may also have mounted thereon discrete devices, such as decoupling or de-bounce capacitors  34 . Capacitors  34  serve to minimize transient noise imputed onto trace conductors  32 .  
           [0012]    In addition to the printed circuit board (or card) on which memory  30   b , memory controller  30   a , and capacitors  34  are secured, card  10  can also take on a covering  36  which surrounds and protects the integrated circuits and capacitors mounted to card  10 . Formed as part of covering  36  is a tab or switch  38  that, when moved, prevents a write operation to the memory integrated circuit. Switch  38  thereby suffices to “write protect” memory card  10 . Any signals sent to edge conductors  12  intended to be written onto the storage elements of memory  30   b  will be prevented from being stored therein if switch  38  is activated. Activation can occur simply by moving switch  38  from one position to another along the sidewall surface of card  10 .  
           [0013]    The memory card  10  shown in the configuration of FIGS. 1 and 2 gained popularity, for example, during the advent of flash memory. Flash memory can be easily erased and reprogrammed. Once reprogrammed, the data within the flash memory is said to be non-volatile and remains until erased or again reprogrammed. Thus, card  10  can be erased and reprogrammed while in receptor  22  provided, of course, that switch  38  is not in the write protect position. Once programmed, any data stored within non-volatile memory  30   b  of card  10  will remain, thereby allowing card  10  to be removed and reinserted at a later time whenever that data is needed—similar to a floppy disk.  
           [0014]    At present there are numerous types of memory cards having the aforesaid characteristics. Popular such memory cards include: Sony&#39;s memory stick, compact flash, smart media, PC cards, flash path, multimedia cards and secure digital. All of the well-known memory cards typically have both a memory controller and non-volatile memory mounted on the card itself, or have the controller form a part of the memory interface, all of which are interconnected to the edge connectors. In order to be usable in multiple electronic systems made by different manufacturers, the industry has imposed a standard on the size of many memory cards. For example, Personal Computer Memory Card International Association (PCMCIA) or Japanese Electronic Industry Development Association (JEIDA) implemented a standard dimension for what are dubbed as Type I, Type II or Type III cards. A Type I memory card measures approximately 2.126×3.37 inches, and is approximately 3.3 mm thick. A Type II memory card is approximately 5.0 mm thick, yet has the same length and width measurements as the Type I card. Under development is a further standard, known as Type III memory card, which is slated to be approximately 10.5 mm thick. All such types of cards are approximately 3.3 mm thick along their guide rails so thinner cards can fit newer, thicker slots. The Type I, Type II, and Type III memory cards are oftentimes referred to as PC cards since the memory cards are sometimes used as a slide-in memory for a personal computer. In addition, multimedia memory cards and secure digital memory cards are often dimensioned 32 mm ×24 mm, with a thickness of 1.4 mm or 2.1 mm, respectively. A smart media card is, however, made approximately 45 mm×37 mm, with a thickness of about 0.70-0.88 mm.  
           [0015]    Regardless of whether the memory card is dimensioned according to PCMCIA or JEIDA standards, or is dimensioned as a multimedia card, a secure digital card, a compact flash card, a smart media card or a flash path card, the memory card is one that must fit in a receptor specifically designed to receive a memory card manufactured by one of numerous manufacturers. Additionally, the memory card is considerably larger than a conventional packaged integrated circuit, which generally has no defined outer dimension since a packaged integrated circuit does not bear edge connectors placed only at one edge of the integrated circuit package for slide engagement into a receptor of an electronic system. Such systems include digital cameras, laptap computers, handheld PDAs that often have a slot to receive additional memory afforded by the memory card. The secure digital memory card can have a mechanical switch mounted on the outer covering to prevent writing of data to the integrated circuit. Various other memory cards may or may not have such a switch.  
           [0016]    It would be desirable to be able to manufacture a memory card using a conventional edge connector arrangement employed by memory cards, and dimensioned according to standards used by legacy memory card manufacturers. The desired memory card would, however, avoid using a printed circuit board or card for electrical routing or as a backbone for mechanical stability. The desired memory card could be classified as a memory module made of less expensive materials and in less time than conventional memory cards. The desired memory module avoids the most expensive component of a memory card by eliminating the cost and lead time needed to form package material about an integrated circuit, form printed conductors upon and within a card, and form the connection between leads of the integrated circuit and printed conductors upon (or within) the card.  
         SUMMARY OF THE INVENTION  
         [0017]    The problems outlined above are in large part solved by a memory module having the dimensions and characteristics of a conventional memory card absent the expense and time in making such a card. The memory module is dimensioned the same as conventional memory cards and functions similar to conventional memory cards, yet can be readily manufactured using essentially a two-step process: mount an un-packaged integrated circuit onto printed conductors absent a mechanical support of a card, and then encase the leads in a material configured according to a conventional memory card standard dimensions.  
           [0018]    The memory module uses an integrated circuit that embodies the memory circuits, the memory controller, and any capacitive elements needed to decouple signal lines on a single monolithic substrate. The first step in processing the memory module entails bonding conductors to bonding pads of the integrated circuit similar to techniques used to bond leads to the integrated circuit when forming a packaged integrated circuit. However, instead of merely packaging the integrated circuit, the bonded conductors can then be encased within an encapsulate that has an outside dimension similar to conventional memory cards. The edge connectors attributable to a memory card are arranged in similar fashion on the memory module, where the conductors serve not only to connect to the integrated circuit bonding pads, but also a portion of each conductor is presented as a substantially planar surface (i.e., pad) that forms the corresponding edge connector.  
           [0019]    According to one embodiment, a plurality of conductors form the edge connectors and receptors for coupling to corresponding bondings pads. The conductors therefore are used to connect electrical signals sent to and from the bonding pads via the edge connectors. Thus, a first end of each of the plurality of conductors are connected to corresponding bonding pads, and a second end of each of conductor is shaped similar to edge connectors of a conventional memory card. Unlike conventional integrated circuit packaging, the present plurality of conductors extend only in one direction from the integrated circuit, thereby, forming a row of second ends near an edge of the memory module. The second ends of the plurality of conductors extend flush with, or possibly extend slightly above or below, the outer surface of the memory module so that, when inserted into a receptor, the second ends which comprise the edge connectors, will be retained only in surface contact with a corresponding planar conductive surfaces within the receptor. The second ends therefore have a planar outer surface that releasibly contacts with a corresponding planar outer surface of conductive elements within the receptors so that the memory module can be slid into and be removed (i.e., released) from the receptor. Meanwhile, the second ends maintain electrical communication with the conductive elements so that the memory module communicates with the electronic system.  
           [0020]    The plurality of conductors can be fingers extending into an opening created within a conductive tape or lead frame. The fingers therefore form a part of the tape or the lead frame used in TAB or wire bond processes, respectively. Thus, the first end of one or more of the plurality of conductors can be secured directly to a corresponding bonding pad using, for example, solder bumps placed on the distal end of the TAB fingers. Alternatively, a wire can be imposed between the lead frame post, or “bond finger,” and a bonding pad on the integrated circuit.  
           [0021]    If a lead frame is used, the post that is coupled to the bonding pad by a wire bond is specially designed. The post (or conductor) can extend, for example, in two planes whereby a first plane can be above or coplanar with a first portion (or paddle) on which the integrated circuit is secured. A second part of the conductor can be configured parallel to the first plane, and below the first plane such that the post (or conductor) extends along the first plane downward at an angle to the second plane. According to one example, the downward angle is less than ninety degrees, and preferably less than 60 degrees from a horizontal plane. The second part, as well as the angled joinder of the first and second parts is encompassed entirely within the resin. The part of the conductor which occupies the second plane forms the edge connector and, therefore, is brought flush with the outer surface of the memory module. The part that extends along the first plane is dimensioned to receive a wire bond. In this fashion, the conductor or lead frame suffices not only to convey signals to and from the integrated circuit, but also is shaped to extend both within the memory module encapsulate material and outside the encapsulate material.  
           [0022]    The memory module can be formed using a simple pair of mold housings, and the integrated circuit purposely avoids having to rest upon any mechanical support other than, for example, a first portion (or “paddle”) of a lead frame. The pair of mold housings will thereby form a cavity which surrounds the TAB-bonded or lead frame-bonded integrated circuit, and liquid resin can be inserted into the cavity. The inner walls of the pair of mold housings which form the cavity are dimensioned as a memory card device with associated width, height, and length configuration of a convention memory card. Thus, the mold cavity is much larger than the silicon substrate of an un-packaged integrated circuit, wherein the mold cavity forms the memory module using flowable encapsulate surrounding solely a lead frame and attached integrated circuit. No intervening card or substrate is needed to support the integrated circuit as in conventional designs where packaged integrated circuits are mounted on a card, or flip-chip secured to a substrate that may be mounted to a card. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]    Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which:  
         [0024]    [0024]FIG. 1 is a perspective view of a memory card having one edge with edge connectors adapted for insertion through a slot of an electronic system and into a receptor, according to one memory card attachment methodology;  
         [0025]    [0025]FIG. 2 is a perspective view of the memory card with packaged integrated circuits mounted upon a rigid printed circuit board and shrouded within a covering;  
         [0026]    [0026]FIG. 3 is a perspective view of a conductive tape containing an opening into which fingers extend in registry above bonding pads of an integrated circuit;  
         [0027]    [0027]FIG. 4 is a detailed block diagram of the integrated circuit of FIG. 4;  
         [0028]    [0028]FIG. 5 is a cross-sectional view along plane  5  of FIG. 4 after the fingers are bonded to the bonding pads and a pair of mold housings are configured around the suspended integrated circuit such that resin is flowed into the space between the mold housings and the integrated circuit;  
         [0029]    [0029]FIG. 6 is cross-sectional view along plane  5  of FIG. 4 after a covering is placed around the ensuing memory module and a portion of hardened resin is removed to expose the conductive fingers arranged in a row along the backside of the memory module;  
         [0030]    [0030]FIG. 7 is a perspective view of a lead frame having first and second portions coplanar to each other, where the first portion is adapted to receive an integated circuit, and the second portion forms one or more conductors spaced laterally from the first portion for receiving a wire bond;  
         [0031]    [0031]FIG. 8 is a cross-sectional view along plane  8  of FIG. 7 after one or more conductors are wire bonded to the bonding pads and a pair of mold housings are configured around the suspended integrated circuit such that resin is flowed into the space between the mold housings and the integrated circuit;  
         [0032]    [0032]FIG. 9 is a cross-sectional view along plane  8  of FIG. 7 after and a portion of hardened resin is removed to expose the conductors arranged in a row along the backside of the memory module;  
         [0033]    [0033]FIG. 10 is a cross-sectional view along plane  8  of FIG. 7 according to an alternative arrangement whereby at least one of the conductors is bent downward to form a conductive surface that is flush with or extends beyond an outer surface of the memory module to avoid backlapping the module;  
         [0034]    [0034]FIG. 11 is a cross-sectional view along plane  8  of FIG. 7 according to an alternative arrangement whereby two or more stacked integrated circuits are bonded to at least one of the conductors that is is bent downward to form a surface of the first and second portions of the lead frame flush or extending beyond an outer surface of the memory module to form a thermally enhanced memory module arrangement; 
     
    
       [0035]    While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.  
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0036]    Turning now to the drawings, FIG. 3 illustrates one example of which bonding pads  40  of integrated circuit  42  are connected to fingers  44  extending from a laminated tape  46 . Tape  46  can be arranged around a spool (not shown), and drawn from that spool to a position above corresponding integrated circuits. For example, tape  46  can be made of tin-plated copper tape using either an additive or subtractive process. Tape  46  can be made of a single layer, such as copper, aluminum, or a combination alloy of each. The tape can alternatively be made of multiple layers, where the electrically conductive layer is bonded to, for example, a polymide dielectric film. Additional layers can also be applied, such as chromium that promotes adhesion between the polymide and copper. The tape can also contain bumps. At the distal end of fingers  44  may be a downward (or upward) extending protrusion, or bump. For example, the bumps can be formed by plating gold over the conductive layer. Alternatively, the integrated circuit can be “bumped.” A bumped integrated circuit is one having solder material “screened” on the bonding pads  40 . Alternatively, gold can be placed on bonding pads  40  extending upward in registry with the distal end of fingers  44 . In either situation, the bumps effectuate solder contact and a highly reliable electrical connection when pressure and heat is applied to tape  46  upon the upper surface of integrated circuit  42 . The process of aligning coplanar fingers within a tape over corresponding bonding pads of integrated circuits and applying heat and pressure to wave solder the fingers to pads can be automated, and is generally regarded as Tape Automated Bonding (TAB).  
         [0037]    In addition to heat and pressure, other mechanisms may also be used to form the connection in a TAB process. For example, adhesives or carbon-filled silicon rubber may be used between the fingers and bonding pads. This can minimize fatigue on the tape caused by heat and pressure. In addition, the bumps can be made either of a solder-based material or tin-lead composite. Alternatively, the bumps can be made mostly of gold which has a much higher conductivity than aluminum, tin, or lead. All of the various improvements for making tape  46 , fingers  44 , bumps on fingers  44  or pads  40 , and securing fingers to corresponding pads are herein contemplated, provided such improvements effectuate a highly reliable and highly conductive connection between the conductive fingers  44  and circuits within integrated circuit  42 .  
         [0038]    [0038]FIG. 4 indicates the various components that can be found on a single integrated circuit. More specifically, the integrated circuit is a single dice within multiple dies arranged across a semiconductor wafer. The integrated circuit  42  represents the culmination of multiple processes applied to a single crystalline silicon base material. Those processes include implant, deposition, etch, clean, and polish steps, among others. Integrated circuit  42  is, however, not placed in a package after it is scribe-removed from the wafer. According to one example, integrated circuit  42  is highly integrated as having the various circuits needed to store data and recall data. Those circuits include an array of memory cells which, according to one example, can be based on non-volatile memory cells  50 . The mechanism in which to direct data to the memory cells and to retrieve data from the memory cells involves a memory controller  52 . Whatever data is sent to and from the memory cells must be kept substantially free of noise. Therefore, decoupling capacitors  54  may be used to maintain a more pristine characteristic of the data sent to and from the storage cells  50 . Conductors which bear data and control signals extend to bonding pads, and are noted as conductors  56 . Conductors  56  terminate at the bonding pads  40 .  
         [0039]    It may be necessary to have certain active bonding pads arranged on one side of each integrated circuit. Preferably, arranged on the opposing side of the integrated circuit could be dummy bonding pads which have bond capability, yet are not connected to any internal circuitry of the integrated circuit. For example, only one side of an integrated circuit can have active bonding pads, and the other three sides of the integrated circuit can have dummy bonding pads. The dummy bonding pads are necessary only for mechanical and assembly reasons, yet do not serve to communicate with internal circuitry of the integrated circuit.  
         [0040]    As shown in FIG. 5, a cross-sectional view along plane  5  of FIG. 3 indicates that an active bonding pad  40   a  is placed near one side of integrated circuit  42 , and a dummy bonding pad  40   b  is placed on the opposed side. Only the active bonding pad  40   a  is connected to internal circuitry of integrated circuit  42 . Active bonding pad  40   a  serves as a connection point to the fingers of the metal foil or metal-laminated tape. The fingers which connect to active bonding pad  40   a  are noted as conductors  60   a.  There are multiple conductors extending in a single direction, as shown in FIG. 3. However, in the cross-section view of FIG. 5, only one conductor is shown. Similar to conductors  60   a , there are other conductors  60   b  that connect to dummy bonding pads  40   b . In this fashion, conductors  60   b  serves merely to support integrated circuit  42  within a cavity formed by a pair of mold housings  62   a  and  62   b . The mold housings  62  clamp toward one another and on opposite sides of conductors  60  that had been previously coupled to integrated circuit  42 . Accordingly, integrated circuit  42  is suspended within the cavity between the inner surfaces of mold housings  62 , yet only conductors  60   a  will eventually extend to the edge connectors of the ensuing memory module.  
         [0041]    [0041]FIG. 5 indicates that after the conductors  60  of the tape are secured and electrically connected to corresponding bonding pads on integrated circuit  42 , the conductors are retained between a pair of mold housings  62 , and liquid resin  66  is injected into the air-filled space surrounding integrated circuit  42 . Contrary to ceramic packaging techniques which leave an air-filled space between the integrated circuit and the package inner surface, the present technique purposely fills that space with an encapsulate that also suffices as the memory module encasement. Thus, the resin itself extends outward from the integrated circuit to an outer surface after the pair of mold housings  62  are removed.  
         [0042]    The resin can be made of any inert component that is non-conductive, yet may have some thermal conductive properties. For example, the resin can be made of silicones, phenolics, and bisphenol (epoxy). The resin can also contain various curing agents, hardeners, accelerators, inert fillers, coupling agents, flame-retardants, stress-relief additives, coloring agents, and mold-release agents. In whatever form, resin  66  is injected in liquid form into the cavity between the inward-facing surfaces of mold housings  62 . After the liquid resin has had sufficient time to cure, it hardens to the form and dimension of a conventional memory card.  
         [0043]    [0043]FIG. 6 illustrates memory module  70  made of hardened resin material  72  which encompasses integrated circuit  42  and conductors  60 . The hardened resin serves to protect the integrated circuit  42  from ingress of moisture, and provides a mechanical support for integrated circuit  42 .  
         [0044]    After resin  72  has hardened, a covering  74  can be placed around the hardened resin. For example, covering  74  can be made of plastic which is heat-shrunk to fit the outer dimensions of the resin, or can be glued or welded at the joint between a two-part assembly of the covering. Memory card  70  may, therefore, be formed either with or without covering  74 . If covering  74  is present, however, a mechanical switch or tab can be formed within the covering, similar to item  38  shown in FIG. 2. Alternatively, the switch can be snap assembled to slots formed in the resin  72 .  
         [0045]    Regardless of whether covering  74  is used, the hardened resin can be partially removed to expose an outer surface of conductor  60   a . Removal  78  can take place either by back-lapping or etching the molded resin in the select region near the edge of memory module  70 . Beneficially, the removal process is employed on the backside surface of the memory module near the forward-leading edge, so that the forward edge can be inserted into a receptor bearing corresponding conductive elements. Alternatively, the molding process can leave the pad areas free of resin by, for example, forming the mold cavity so that a recess can be formed to expose the conductors  60   a.    
         [0046]    [0046]FIG. 7 illustrates an alternative technique for mounting conductors to an integrated circuit. Instead of using a TAB mechanism, FIG. 7 illustrates a lead frame  80 . Lead frame  80  contains a first portion (paddle)  82  that will secure integrated circuit  42  without having to bond the integrated circuit to inoperative (dummy) bonding pads. Lead frame  80  serves to support the molded memory module, and is fabricated from a strip of sheet metal by stamping or chemical milling. Lead frame  80  provides a holding fixture during the assembly process in which bonding pads  40  of integrated circuit  42  are connected to the lead frame. Then after molding, lead frame  80  becomes an integral part of the memory module. The lead frame can be made of numerous materials, such as nickel-iron or copper alloy. Similar to a tape, the lead frame can also be layered as a composite strip, such as a copper alloy placed upon a stainless steel structure.  
         [0047]    Extending outward from the first portion  82  of lead frame  80  are support arms  84 . Support arms  84  thereby secure the position of the first portion  82  relative to a frame  86  which encircles first portion  84 . Extending inward from one side of frame  86  is a series of conductors  88 . Each conductor  88  includes a first portion  90  and a second portion  92 . First portion  90  is relatively thin in upper surface area, while second portion  92  is much wider. Portions  90  and  92  are formed from a single piece of conductive material and extend as an integral piece with items  82 ,  84  and  86 . Thus, support member  84 , first portion  82 , member  86 , and conductors  88  are preferably formed from the same sheet, with each item stamped from that sheet.  
         [0048]    [0048]FIG. 8 illustrates a cross-sectional view along plane  8  of FIG. 7 after integrated circuit  42  is bonded to first portion  82 . For example, the integrated circuit can be bonded using a die adhesive, such as silicon/gold eutectic bonding or by use of a polymer adhesive base. Die adhesive  91  includes any structure that securely fastens integrated circuit  42  to first portion  82 . After integrated circuit  42  is secured, a wire  93  can be ultrasonically or thermosonically welded to one or more conductors  88  and one or more bonding pads  40  upon integrated circuit  42 . After integrated circuit  42  is attached and conductor  88  is electrically connected to a corresponding bonding pad  40 , a pair of mold housings  62  are secured about integrated circuit  42  and a liquid resin  66  is injected into the mold cavity.  
         [0049]    [0049]FIG. 9 illustrates memory module  70  after removal of the pair of mold housings and the back-lapping or etching of the hardened resin to expose conductor  88  as the edge connector. The removal process  78  can be the same as that shown in FIG. 6. Alternatively, the molding process can itself leave the edge connectors exposed. The hardened resin  72  may or may or not be encircled by a covering and, as shown in FIG. 9, no covering need be present.  
         [0050]    [0050]FIG. 10, however, illustrates use of a covering  74  and, more importantly, depicts a bend placed in conductor  88  of the lead frame. Conductor  88  is thereby shown with a first part  90  that receives a wire bond of wire  93 . First part  90  is substantially coplanar with the first portion  82  of the lead frame. Conductor  88 , therefore, extends along a first plane substantially coplanar to the first portion  82 , downward at an angle to a second plane at which the second part  92  resides. Second part  92  has an outer surface which extends flush with the outer surface of the hardened resin  72 . As such, second part  92  is exposed at the forward-leading edge of memory module  70 . By employing a bend within conductor  88 , no back-lapping or etching need take place on the hardened resin material  72  in order to expose an edge of conductor  88 . Additionally, the second part  92  consists of a widened surface (see FIG. 7) that will accommodate conductive elements within, for example, receptors. By bending one or more conductors  88  within a row of conductors, the exposed part  92  of each conductor will form substantially a row of edge connectors at the forward-leading edge of memory module  70 . The edge connectors can be slightly offset from each other along a single axis. Even though one or more edge connectors within a row may be offset from the axis, the edge connectors nonetheless maintain somewhat of an alignment along a line relative to one another. Thus, offset edge connectors can still deemed ones arranged in a row. First portion  82  and integrated circuit  42 , however, remain suspended entirely within the hardened resin  72 . Little if any moisture can, therefore, contact portion  82  or integrated circuit  42 .  
         [0051]    [0051]FIG. 11 illustrates an alternative arrangement, where first part  90  of conductor  88  can be arranged in a plane above first portion  82 . Unlike the arrangement in FIG. 10 where first part  90  is coplanar with first portion  82 , the first part  90  of FIG. 11 is above the plane formed by first portion  82 , and second part  92  is coplanar with first portion  82 . FIG. 11, therefore, illustrates elevating conductor  88  above first portion  82  to serve not only to expose second part  92  as an edge connector, but also to expose the backside surface of first portion  82 . Recall that portion  82  is a conductive element, and that die adhesive  91  may be thermally conductive. This allows any heat build-up within integrated circuit  42  to be transferred downward to the thermally conductive elements  91  and  82 . As such, the thermally conductive portion  82  will operate as a heat sink to remove heat away from integrated circuit  42 .  
         [0052]    It may be desirable that memory module  70  use two or more integrated circuits. For example, one integrated circuit may simply contain the memory storage element, and another integrated circuit be used to contain the memory controller and any decoupling capacitors needed. Alternatively, the first integrated circuit can contain storage elements and a controller, while the second integrated circuit can also contain storage elements and a controller, similar to the first integrated circuit. If, for example, a single integrated circuit does not contain all of the storage elements, controller, and decoupling components, memory module  70  can accommodate one integrated circuit stacked upon another using a die adhesive  91  placed therebetween. The second integrated circuit  42   a  can be shifted or offset laterally from integrated circuit  42 . Alternatively, the second integrated circuit need not be offset if, for example, the second integrated circuit is spaced from the integrated circuit by a spacer that can accommodate wires coupled to the underlying bonding pads. In either instance, measures need be taken to enable a row of bonding pads on the lower integrated circuit to be exposed if, for example, wire bonding is needed. Since only those bonding pads arranged near one side of an integrated circuit are bonded, the second integrated circuit can be placed over the lower integrated circuit possibly offset according to the configuration shown. Wire bonds can emanate from bonding pads of both the upper and lower integrated circuits to corresponding first part  90  of respective conductors  88 .  
         [0053]    It will be appreciated to those skilled in the art having the benefit of this disclosure that the details provided herein are believed to denote a memory module that can be formed without having to first package an integrated circuit, and then bond leads of the packaged integrated circuit to a printed circuit board or card. The memory module thereby avoids using cards as the backbone of mechanical support and electrical connectivity normally employed in conventional memory cards. The improved memory module can have further modifications and alternative forms to include various aspects of the present invention, as will be apparent to those skilled in art after having reviewed this description. It is intended that the following claims be interpreted to embrace all such modifications and changes and, accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.