A probe card assembly includes a probe card, a space transformer having resilient contact structures (probe elements) mounted directly to (i.e., without the need for additional connecting wires or the like) and extending from terminals on a surface thereof, and an interposer disposed between the space transformer and the probe card. The space transformer and interposer are “stacked up” so that the orientation of the space transformer, hence the orientation of the tips of the probe elements, can be adjusted without changing the orientation of the probe card. Suitable mechanisms for adjusting the orientation of the space transformer, and for determining what adjustments to make, are disclosed. The interposer has resilient contact structures extending from both the top and bottom surfaces thereof, and ensures that electrical connections are maintained between the space transformer and the probe card throughout the space transformer's range of adjustment, by virtue of the interposer's inherent compliance. Multiple die sites on a semiconductor wafer are readily probed using the disclosed techniques, and the probe elements can be arranged to optimize probing of an entire wafer. Composite interconnection elements having a relatively soft core overcoated by a relatively hard shell, as the resilient contact structures are described.

Probe card assembly and kit, and methods of making same

Microelectromechanical systems (MEMS) devices are made of doped single-crystal silicon, LPCVD polysilicon films, and other ceramic films. Very little is understood about tribology and mechanical characterization of these materials on micro- to nanoscales. Micromechanical and tribological characterization of p-type (lightly boron-doped) single-crystal silicon (referred to as “undoped”), p+-type (boron doped) single-crystal silicon, polysilicon bulk, and n+-type (phosphorous doped) LPCVD polysilicon films have been carried out. Hardness, elastic modulus, and scratch resistance of these materials were measured by nanoindentation and microscratching using a nanoindenter. Friction and wear properties were measured using an accelerated ball-on-flat tribometer. It is found that the undoped silicon and polysilicon bulk as well as n+-type polysilicon film exhibit higher hardness and elastic modulus than the p+-type silicon. The polysilicon bulk and n+-type polysilicon film exhibit the lowest friction and highest resistance to scratch and wear followed by the undoped silicon and with the poorest behavior of the p+-type silicon. During scratching, the p+-type silicon deforms like a ductile metal.

Micromechanical and tribological characterization of doped single-crystal silicon and polysilicon films for microelectromechanical systems devices

A method of reducing the area of MCMs that are integral to a flexible carrier is provided. A locally complex area, i.e. multilayer MCM carrier is constructed on a flex carrier, along with other components to form a subsystem. The flex carrier provides the interface between the MCM and the system that is utilizing the function. Also, the flex carrier will receive non-complex portions of the function, e.g. low I/O devices, not required to be mounted on the complex area (MCM) of the subsystem. The locally complex functional area will contain the high performance DCA mounted components, such as custom ASICs, processors, high frequency analog parts and other high I/O chips. The MCM on flex is constructed by obtaining an appropriate flexible carrier, such as a dielectric material having electrically conductive signal lines circuitized on both sides. A photoimageable dielectric layer is then placed over the appropriate portion of the circuitized carrier and vias are formed therein and filled with electrically conductive material. The top side of the dielectric layer is then circuitized and electrically connected to the flex carrier wiring layers as required. Additional layers are then built as needed by an identical process. Electrically conductive pads are formed on the top circuitized dielectric layer in order to provide an interconnection point for the chip I/Os that will be directly attached thereto.

Formulation of multichip modules

A connection component for electrically connecting a semiconductor chip to a support substrate incorporates a preferably dielectric supporting structure defining gaps. Leads extend across these gaps so that the leads are supported on both sides of the gap. The leads therefore can be positioned approximately in registration to contacts on the chip by aligning the connection component with the chip. Each lead is arranged so that one end can be displaced relative to the supporting structure when a downward force is applied to the lead. This allows the leads to be connected to the contacts on the chip by engaging each lead with a tool and forcing the lead downwardly against the contact. Preferably, each lead incorporates a frangible section adjacent one side of the gap and the frangible section is broken when the lead is engaged with the contact. Final alignment of the leads with the contacts on the chip is provided by the bonding tool, which has features adapted to control the position of the lead.

Semiconductor connection components and methods with releasable lead support

A barrier layer is deposited over a layer of passivation including in an opening to a contact pad created in the layer of passivation. A column of three layers of metal is formed overlying the barrier layer and aligned with the contact pad and having a diameter that is about equal to the surface of the contact pad. The three metal layers of the column comprise, in succession when proceeding from the layer that is in contact with the barrier layer, a layer of pillar metal, a layer of under bump metal and a layer of solder metal. The layer of pillar metal is reduced in diameter, the barrier layer is selectively removed from the surface of the layer of passivation after which reflowing of the solder metal completes the solder bump of the invention.

Low fabrication cost, fine pitch and high reliability solder bump

The storage capacities and areal densities found in magnetic disk drives are increasing very rapidly. Data is recorded in ever-narrower tracks which must be followed with extreme precision. Also, the advent of portable applications exposes these smaller drives to higher levels of vibration and shock. A description is given of the many factors which contribute to recording track misregistration (TMR) in today's drives. The mechanics of the drive and actuator and the architecture of the servo control system are also described. A projection is made for the TMR sensitivities and control system at an areal density of 10 Gb/in/sup 2/, having roughly 25000 tracks/in. A two-stage servo may be needed to achieve such track densities. This would comprise a high bandwidth microactuator for rapid position corrections of the recording head, coupled with a conventional actuator. The characteristics of such a microactuator are discussed, and operational examples of fabricated electroplated microactuators, driven electrostatically, are shown. The mechanical behavior of the devices and some of the factors which would affect their implementation are also described. >

Magnetic recording-head positioning at very high track densities using a microactuator-based, two-stage servo system

A semiconductor chip carrying integrated circuits has lead lines terminating in conductive terminal pads exposed to the exterior through openings in a passivation layer. The pads include pedestals or bumps extending up from them. Each of the pedestals includes a thin metallic adhesion layer deposited on the pad. A thick metallic layer of aluminum or an alloy of aluminum is deposited upon said thin metallic adhesion layer. The thick metallic layer includes at least one metal selected from the group consisting of aluminum, aluminum plus a small percentage of Cu, Ni, Si, or Fe. Several other alternative metals can be added to aluminum to form an alloy. The thick metallic layer forms the bulk of the height of the pedestal. An adhesion layer is deposited on the bump of aluminum composed of a thin film of titanium or chromium. A barrier layer is deposited on the adhesion layer composed of copper, nickel, platinum, palladium or cobalt. A noble metal consisting of gold, palladium, or platinum is deposited on the barrier layer. In a variation of the top surface, a thick cap of a reworkable bonding metal is deposited above the metallic bump as the top surface of said bump. The bump can be composed of a number of metals such as gold, copper, nickel and aluminum in this case with aluminum being preferred. In place of the adhesion and barrier metals one can employ a layer of titanium nitride deposited on said thick layer of metal.

Aluminum bump, reworkable bump, and titanium nitride structure for tab bonding

A method and apparatus for controlling a multiple-stage actuator for a disk drive which does not require an additional sensor for measuring the relative position between adjacent actuator stages. In a two-stage actuator system, a position-type secondary actuator (SA) rides piggyback on a primary actuator (PA). The repeatable runout is measured and used as a feedforward signal to the PA. If the PA is a rotary actuator, the feedforward signal is preferably arc corrected for the arc that the head transverses from the inner radius to the outer radius of the disk. Added to the feedforward signal is the moving average of the drive signal applied to the SA. Because the SA is of the position-type having a neutral position, this moving average is proportional to the time cumulative drift present in the two-stage actuator system, and forces the PA in a direction that minimizes deviation of the SA from its neutral position. This minimizes the range requirement for the SA, the main purpose of which is to reduce non-repeatable runout.

Method and apparatus for controlling a multiple-stage actuator for a disk drive

An integrated circuit device package in which integrated circuit devices are mounted with active faces placed facing each other to form a double-device structure. Input/output terminals on the active faces of each device can be electrically interconnected by placing an interconnection means between the chips to electrically interconnect input/output terminals on the active faces of the first and second device. Beam leads, each having an inner and outer lead bond site, project outwardly from between the devices where each of the inner lead bond site is solderlessly bonded between conducting patterns on each device bonded. A series of double-device structures can be formed on a tape having a plurality of sets of beam lead patterns thereon. Each beam lead of each set having an inner and outer lead bond site, projects outwardly from between the double-device structure, the inner lead bond site being solderlessly bonded between conducting patterns on each device.

Double electronic device structure having beam leads solderlessly bonded between contact locations on each device and projecting outwardly from therebetween

A bistable micromechanical switch that includes a substrate, at least two anchor points formed on the substrate, and a beam structure that includes a two-material beam attached to at least two anchor points The two-material beam has a first portion, a second portion and a center portion The first portion of the two-material beam is formed from a first layer of a first material and a second layer of a second material such that the first layer of the first portion is proximate to the surface of the substrate and the second layer of the first portion is remote from the surface of the substrate The first material has a first coefficient of thermal expansion and the second material has a second coefficient of thermal expansion such that the second coefficient of thermal expansion is greater than the first coefficient of thermal expansion The second portion of the two-material beam is formed from a first layer of the second material and a second layer of the first material such that the first layer of the second portion is proximate to the surface of the substrate and the second layer of the second portion is remote from the surface of the substrate The beam structure has a first and a second stable state such that the center portion of the beam structure is deflected toward the surface of the substrate for the first stable state and is deflected away from the surface of the substrate for the second stable state

Timothy Clark Reiley

Papers

Magnetic recording-head positioning at very high track densities using a microactuator-based, two-stage servo system

Aluminum bump, reworkable bump, and titanium nitride structure for tab bonding

Method and apparatus for controlling a multiple-stage actuator for a disk drive

Double electronic device structure having beam leads solderlessly bonded between contact locations on each device and projecting outwardly from therebetween

Bistable micromechanical switches