Abstract:
A deflection element operating under control of selectively applied energy is used to achieve low insertion loss between mating elements. Once the elements are in proper relationship the deflection element is allowed to settle to its stable position thereby serving to lock the elements together.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is related to commonly assigned U.S. patent application Ser. No. 09/570,170, filed May 11, 2000, entitled “SYSTEM AND METHOD FOR COUPLING MICROCOMPONENTS”; Ser. No. 09/569,328, filed May 11, 2000, entitled “RIBBON CABLE AND ELECTRICAL CONNECTOR FOR USE WITH MICROCOMPONENTS”; and Ser. No. 09/643,011, filed Aug. 21, 2000, entitled “SYSTEM AND METHOD FOR COUPLING MICROCOMPONENTS UTILIZING A PRESSURE FITTING RECEPTACLE”; incorporated by reference herein 

   FIELD OF THE INVENTION 
   This invention relates to micro/nanotechnology connectors and more particularly to a system and method for achieving low insertion force by controlled deformation of mating elements. 
   BACKGROUND OF THE INVENTION 
   In the above-referenced co-pending patent applications there are disclosed systems and methods for achieving low insertion force while bringing mating elements together in a micro/nanotech environment. Typically, to accomplish low, or ideally zero, insertion force between mating elements, some deflection of one of the mating elements must be achieved. This deflection comes about by using ‘tweezers’ that grab and squeeze a mating element. Using the tweezers, the deflected element to be mated is guided into a location where, when the force is removed, the friction that results from the undeflected element latches the parts together. 
   Such a procedure has an advantage since the element must be guided anyway, therefore applying pressure to deflect the element is a logical step in the guiding process. However, applying deflection forces in this manner presents some disadvantages, particularly when there are several connections to be made between elements. In such a situation, the element must be “grabbed” or deflected in several places at the same time. 
   Another problem is that the requirement to squeeze an clement imposes constraints on the gripper mechanism and complicates the assembly tools and procedures. One such constraint is that the assembly gripper must then be designed for each individual element so as to achieve the proper gripping force, rotation, and mating relationships. 
   When the gripper device that is being used to position the element also supplies the deflection force it follows that when the deflection force is removed the maneuvering force is also removed, or lessened. In some situations, this is not desirable. 
   Also, self-centering and minor adjustments are necessary when elements are to be mated. Thus, any system that is designed to achieve the smooth mating of elements must also be designed to allow for slight adjustments. It follows then that when an element is being deflected by the tool that is also positioning that element any change in the pressure on the tool (release of the deflection) can also result in a change to the spatial orientation of the element. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention is directed to a system and method in which energy is applied to an element to be mated and the energy causes one or more of the mating elements to deflect enough to provide a low, or zero, insertion force Removal of the energy causes the element, or elements, to assume their static, or rest, shape, thereby increasing the friction (or other attractive force), or latching between the parts enough to cause the elements to resist separation. Positional adjustments can be made, either during the mating process or thereafter, by the selective application of energy to cause selective deformation. 
   The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which: 
       FIG. 1  shows a conceptual view of a device being mated to a surface using the system and method of our invention; 
       FIG. 2  shows one embodiment of our invention; 
       FIG. 3  shows the embodiment of  FIG. 2  arranged in a multiple configuration; 
       FIG. 4  shows the multiple configuration of  FIG. 3  being used to position other elements; and 
       FIG. 5  shows a conceptual view of a device being mated to a surface where electrical connections are made. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  shows system  10  with a conceptual view of actuator  11  which, for example, can be a snap connector of the type shown in the above-identified patent applications. At the top of actuator  11  is handle  16  used, if desired, to grip the connector and move it about. Shown on handle  16  are electrical (or other energy source) contacts  107 ,  108 , and  109 . In the embodiment shown, contact  108  is a direct ohmic contact to the electrically conducting body  19  (doped Si in this instance) of the connector. Contacts  107  and  109  as well as electrical traces  20  and  21  are separated from the body of connector  19  by a dielectric layer such as SiO 2 . Electrical traces  20  and  21  cross over dielectric trenches  102  and  103  and connect to contacts  22  and  23 , respectively, so as to make electrical contact with conductor  101 . 
   Electric current can be made to flow through connector  11  from contact  108  to  107  and  109 . Because of the bilateral symmetry of the connector, we will only describe the electrical path from contact  109  to  108 . With a potential difference between contacts  109  and  108 , a current will flow from contact  109  through electrical trace  20  and contact  22  through conductor  101 , through hot arm  18 , back up through cold arm  19 , into body  19  of activator  11 , to contact  108 . This current path is forced by dielectric filled trench  102  and air gap  12 . Element  14  (and  13 ) is a thermal actuator which moves when hot arm  18  expands more than does cold arm  19  because of the larger current density in the hot arm leading to higher temperatures therein. 
   These elements  13  and  14  are designed to deflect inward a distance such that element  13  is centered within receptacle  13 ′ of substrate  17 , while element  14  is centered within receptacle  14 ′. If desired, stops  104  can be positioned to control the depth of the insertion within substrate  17 . In the embodiment shown, the application of power to elements  12  cause legs  13  and  14  to deflect. 
   When the elements are positioned as desired, the energy can be fully, or partially, removed, allowing the deflected elements to assume their rest condition. In the embodiment shown, element  13  would then become positioned against side wall  110 , while element  14  would be come positioned against side wall  111 . 
   In an alternate embodiment, connector  11 , or substrate  17 , could be designed such that legs  13 ,  14  assume their steady-state condition. Further deflection, by one or more of legs  13 ,  14 , could be achieved so as to increase the bonding (friction) forces. Also, selective additional deflection could be used to reposition the alignment of the connector. 
   Also note that during the insertion process, one or more elements to  13 ,  14  could be deformed and the deformation could be by selective amounts. 
   Also note, in the embodiment shown, the energy is an electrical current which causes a thermal (or other) change in the deflection element. The current can be removed while pressure is still being applied to handle  16 . Other sources of energy could be used, such as, for example, thermal, and hydraulic. 
   In operation, once the current is removed, activator  11  becomes locked to substrate  17  by the outwardly applied restoring forces from elements  13 ,  14 . Elements  13  and  14  will lock into mating slots  13 ′ or  14 ′, respectively, by friction, bonding (chemical or glue) or by latching, or a combination thereof. If it is desired to later separate the connector from the substrate, energy can be reapplied to terminals  107 - 109  (or by some other means) again causing the elements to deform to aid in the separation. 
   Also in operation, it is necessary to be able to send energy, such as electricity, through the conducting silicon so there needs to be a channel or pathway  101 ,  18 ,  19  through the silicon that separates one portion from another. Dielectric  102 ,  103  serve this function. Dielectric elements  102  and  103  are trenches etched in the body of the connector and filled with dielectric to provide a rigid connection between sections  101  and  19 . To accomplish this, the process starts off as a flat piece of silicon, for example, SOI silicon, as a top layer. An offset is constructed underneath by etching or other process and dielectric  102 ,  103  is filled back into the etched channel. The dielectric can be an oxide or a nitride, which provides the mechanical contact between  101  and  19 , and which provides the electrical isolation between the parts to allow for the deformation process. 
   Elements  13  and  14  can be thought of as a thermal bi-morph and operated because they have different cross-sections causing them to heat differently and thus bend as discussed above. 
     FIG. 2  shows connector  20  which is more in keeping with the type of connectors envisioned. Connector  20  includes power supply connectors  203 A and  203 B for delivering energy to deformable (movable) elements  202 . 
   In operation, when energy is supplied, elements  202 , on both sides of element  22  move upward under control of the supplied energy. Typically, this movement would be thermally induced. When these elements move upward they move element  22  upward, which, in turn, pulls bar  24  upward. Bar  24  moving upward causes arms  201 A and  201 B to pivot around points  23 . As the arms pivot, mating elements  201 A and  201 B (which can be any shape) move closer together, in preparation, if so desired, for mating with another element (not shown). This type of bent beam actuator can be thought of as a thermally amplified actuator. 
     FIG. 3  shows device  30  where two (or more if desired) connector  20 &#39;s are ganged together both physically and electrically. Note that each pair of movable connector legs  201 A and  201 B can be moved either together with the other pair or individually, depending upon how they are electrically or mechanically interconnected. 
     FIG. 4  shows device  40  which has two pairs of controllably movable elements  201 A and  201 B, which can be two snap connectors as shown on  FIG. 3  which latch into mating structures  201 A′ and  201 B′, respectively of structure  410 . In addition, device  40  shows that device  40  can act to position another element, such as element  41 , via plates  401  under control of arms  402 . Arms  402 , in turn, are actuators for moving plate  401  up and down. 
     FIG. 5  shows conceptual device  51 , which is essentially the same as device  11 , except that passive contact pad  53  has been added to allow for bringing connector  51  into electrical contact with substrate  17  via contacts  502 A- 502 D. Also, if desired, there could be added electrical contact pads  501 A and  501 B which mate with contacts  504 A and  504 B, respectively. Note that one use for pads  501 A and  501 B would be to reenergize elements  14  to further expand elements  14 , if and when necessary. This would be akin to using a feedback loop to maintain proper contact. Contact  511 (A/B) can be used to supply power to contact  501 (A/B) via powerline  510  (A/B). The expansion could be controlled by making a “reverse” bi-morph from sections of elements  13  and  14  such that elements  13  and  14  move outward upon the application of power to terminals  511 A and  511 B. The current connection for this could be, for example, from terminal  504 A through arm  14  to and via connector  19  to arm  13  and terminal  504 B. Connection between contacts  511 A and  501 A can be accomplished, for example, by making  510 A a metal overlay running up side wall  111  and extending  501 A to the surface. 
   The connectors shown in the FIGURES could, if desired, be constructed using the MEMS process. If MEMS is used, the addition of deformable sections can be incorporated into the manufacturing process for little additional cost. In addition, it should be noted that the actuators can be positioned in various locations around a connector, all of which need not be activated at one time. This would allow for the connection to multiple different structures at different times. 
   Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compostions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.