Abstract: A method and structure for forming a spring structure that avoids undesirable kinks in the spring is described. The method converts a portion of a release layer such that the converted portion resists etching. The converted portion then serves as an anchor region for a spring structure deposited over the release layer. When the non-converted portions of the release layer are etched, the spring curls out of the plane of a plane.

Abstract: A method of forming spring structures using a single lithographic operation is described. In particular, a single lithographic operation both defines the spring area and also defines what areas of the spring will be uplifted. By eliminating a second lithographic operation to define a spring release area, processing costs for spring fabrication can be reduced.

Abstract: A curved transmission-line spring structure formed by self-bending materials (e.g., stress-engineered materials, intermetallic compounds and/or bimorphs) that are layered to form a stripline or microstrip transmission line. A dielectric layer is sandwiched between two conductive layers, which form the signal and ground lines of the structure. The various layers are etched to form an elongated spring structure, and then one end of the spring structure is released from the underlying substrate, causing the tip of the released end to bend away from the substrate for contact with a second device. One or both of the conductive layers is fabricated using self-bending spring metals to facilitate the bending process, and plated metal is utilized for conductivity. Alternatively, or in addition, the dielectric layer is formed using a stress-engineered dielectric material. Two-tip and three-tip structures are used to facilitate connection of both the ground and signal lines.

Abstract: An out-of-plane micro-structure which can be used for on-chip integration of high-Q inductors and transformers places the magnetic field direction parallel to the substrate plane without requiring high aspect ratio processing. The photolithographically patterned coil structure includes an elastic member having an intrinsic stress profile. The intrinsic stress profile biases a free portion away from the substrate forming a loop winding. An anchor portion remains fixed to the substrate. The free portion end becomes a second anchor portion which may be connected to the substrate via soldering or plating. A series of individual coil structures can be joined via their anchor portions to form inductors and transformers.

Abstract: A spring contact has a post-release outer upper surface in compression and a post-release outer lower surface in compression. A compressive lower layer of spring material may be formed at a thickness that is three-eighths or less of a tensile upper layer of spring material. A low modulus of elasticity cladding material may also be applied to the outer surface of the spring contact with a lower surface of the cladding material being formed with a compressive stress.

Abstract: Fluidic conduits, which can be used in microarraying systems, dip pen nanolithography systems, fluidic circuits, and microfluidic systems, are disclosed that use channel spring probes that include at least one capillary channel. Formed from spring beams (e.g., stressy metal beams) that curve away from the substrate when released, channels can either be integrated into the spring beams or formed on the spring beams. Capillary forces produced by the narrow channels allow liquid to be gathered, held, and dispensed by the channel spring probes. Because the channel spring beams can be produced using conventional semiconductor processes, significant design flexibility and cost efficiencies can be achieved.

Abstract: Methods are disclosed for fabricating spring structures that minimize helical twisting by reducing or eliminating stress anisotropy in the thin films from which the springs are formed through manipulation of the fabrication process parameters and/or spring material compositions. In one embodiment, isotropic internal stress is achieved by manipulating the fabrication parameters (i.e., temperature, pressure, and electrical bias) during spring material film formation to generate the tensile or compressive stress at the saturation point of the spring material. Methods are also disclosed for tuning the saturation point through the use of high temperature or the incorporation of softening metals. In other embodiments, isotropic internal stress is generated through randomized deposition (e.g., pressure homogenization) or directed deposition techniques (e.g., biased sputtering, pulse sputtering, or long throw sputtering). Cluster tools are used to separate the deposition of release and spring materials.

Abstract: An electrical interconnect structure that includes a spring portion that extends out of a plane. The electrical interconnect including curved regions to improve the lateral compliance of the interconnect. The curved region may be incorporated into a release region of the spring. The release region may include either or both an uplifted region and a planar region. The curves in the release region are arranged to improve the spring contact with a mating surface and also improve lateral compliance compared to prior art spring designs.

Abstract: An alternating current (AC) solar power apparatus includes a photovoltaic cell and a circuit or device for causing a signal generated by the photovoltaic cell to oscillate in a negative differential resistance range, thereby producing an AC output voltage. The photovoltaic cell exhibits negative differential resistance in its current/voltage (IV) curve in the presence of high flux illumination, wherein when the output voltage is within a negative differential resistance range, an incremental increase in the output voltage produces an associated decrease in generated current. By connecting the terminals of the photovoltaic cell to a resonator (e.g., an inductive-capacitive circuit) or other device that produces oscillation within the negative differential resistance range, the photovoltaic cell is caused to produce AC power.

Abstract: A data transmission interconnect assembly capable of transmission speeds in excess of 40 Gbps in which, for example, a line-card is detachably coupled to a backplane using flexible flat cables that are bent to provide a continuous, smooth curve between the connected boards, and connected by a connection apparatus that employs cable-to-cable interface members that are transparent to the transmitted signal waves. Microspring interface members are formed on the contact structure pressed against the cables to provide interface arrangements that are smaller than a wavelength of the transmitted signal. A connector apparatus uses a cam mechanism to align the cables, and then to press the contact structure, having the microspring interface members formed thereon, against the cables. An alterative contact structure uses anisotropic conductive film.

Abstract: A socket for solderless connection between a stud-bumped IC chip and a host PCB. The socket includes a three-dimensional (e.g., cylindrical or cubical) hollow metal frame that is either free-standing or supported by an underlying patterned template structure. The metal frame includes side walls that extend away from the host PCB, and a contact structure located at the upper (i.e., free) end of the side walls. The contact structure defines an opening through which a stud bump can be inserted into a central chamber of the metal frame. The side walls and/or the contact structure are formed such that when the tip end of the stud bump is inserted into the central chamber, at least one of the base structure and the sidewall of the stud bump abuts the contact structure at two or more contact points.

Abstract: Lithographically defined and etched spring structures are produced by various methods such that they avoid the formation of a plated metal wedge on an underside of the spring structure after release. A post is utilized to offset the spring from an underlying substrate by a distance greater than the thickness of the plated metal. A trench is etched into the substrate below the spring to provide clearance during deflection of the spring. Another spring includes a knee (bend) that provides the necessary clearance during deflection. A plating process is limited to the upper side of another spring. A released spring is used as a shadow mask for patterning resist that prevents wedge formation during plating.

Abstract: An out-of-plane micro-structure which can be used for on-chip integration of high-Q inductors and transformers places the magnetic field direction parallel to the substrate plane without requiring high aspect ratio processing. The photolithographically patterned coil structure includes an elastic member having an intrinsic stress profile. The intrinsic stress profile biases a free portion away from the substrate forming a loop winding. An anchor portion remains fixed to the substrate. The free portion end becomes a second anchor portion which may be connected to the substrate via soldering or plating. A series of individual coil structures can be joined via their anchor portions to form inductors and transformers.

Abstract: Spring structures are subjected to pre-release and post-release annealing to tune their tip height to match a specified target. Post-release annealing increases tip height, and pre-release annealing decreases tip height. The amount of tuning is related to the annealing temperature and/or time. Annealing schedules are determined for a pre-fabricated cache of unreleased spring structures such that finished spring structures having a variety of target heights can be economically produced by releasing/annealing the cache according to associated annealing schedules. Selective annealing is performed using lasers and heat absorbing/reflecting materials. Localized annealing is used to generate various spring structure shapes. Both stress-engineered and strain-engineered spring structures are tuned by annealing.

Abstract: A data transmission interconnect assembly (e.g., a router) capable of transmission speeds in excess of 40 Gbps in which a line-card is detachably coupled to a backplane using flexible flat cables that are bent to provide a continuous, smooth curve between the connected boards, and connected by a connection apparatus that employs cable-to-cable interface members that are transparent to the transmitted signal waves. Microspring contact structures are formed on the cables, or on a contact structure pressed against the cables, to provide interface arrangements that are smaller than a wavelength of the transmitted signal. A connector apparatus uses a cam mechanism to align the cables, and then to press a contact structure, having micro spring interface members formed thereon, against the cables. An alterative contact structure uses anisotropic conductive film.

Abstract: An out-of-plane micro-structure which can be used for on-chip integration of high-Q inductors and transformers places the magnetic field direction parallel to the substrate plane without requiring high aspect ratio processing. The photolithographically patterned coil structure includes an elastic member having an intrinsic stress profile. The intrinsic stress profile biases a free portion away from the substrate forming a loop winding. An anchor portion remains fixed to the substrate. The free portion end becomes a second anchor portion which may be connected to the substrate via soldering or plating. A series of individual coil structures can be joined via their anchor portions to form inductors and transformers.

Abstract: Methods are disclosed for fabricating spring structures that minimize helical twisting by reducing or eliminating stress anisotropy in the thin films from which the springs are formed through manipulation of the fabrication process parameters and/or spring material compositions. In one embodiment, isotropic internal stress is achieved by manipulating the fabrication parameters (i.e., temperature, pressure, and electrical bias) during spring material film information to generate the tensile or compressive stress at the saturation point of the spring material. Methods are also disclosed for tuning the saturation point through the use of high temperature or the incorporation of softening metals. In other embodiments, isotropic internal stress is generated through randomized deposition (e.g., pressure homogenization) or directed deposition techniques (e.g., biased sputtering, pulse sputtering, or long throw sputtering). Cluster tools are used to separate the deposition of release and spring materials.

Abstract: An out-of-plane micro-structure which can be used for on-chip integration of high-Q inductors and transformers places the magnetic field direction parallel to the substrate plane without requiring high aspect ratio processing. The photolithographically patterned coil structure includes an elastic member having an intrinsic stress profile. The intrinsic stress profile biases a free portion away from the substrate forming a loop winding. An anchor portion remains fixed to the substrate. The free portion end becomes a second anchor portion which may be connected to the substrate via soldering or plating. A series of individual coil structures can be joined via their anchor portions to form inductors and transformers.

Abstract: Several methods and structures for improving the yield of out-of-plane micro-device structures including springs and coils are described. In one method the springs used to form out-of-plane structures are constrained via a tether to avoid bunching and entanglement. The high yield structure may be used in numerous electronic applications such as filter circuits.

Abstract: A stress-balancing layer formed over portions of a spring metal finger that remain attached to an underlying substrate to counter internal stresses inherently formed in the spring metal finger. The (e.g., positive) internal stress of the spring metal causes the claw (tip) of the spring metal finger to bend away from the substrate when an underlying release material is removed. The stress-balancing pad is formed on an anchor portion of the spring metal finger, and includes an opposite (e.g., negative) internal stress that counters the positive stress of the spring metal finger. A stress-balancing layer is either initially formed over the entire spring metal finger and then partially removed (etched) from the claw portion, or selectively deposited only on the anchor portion of the spring metal finger. An interposing etch stop layer is used when the same material composition is used to form both the spring metal and stress-balancing layers.