Abstract: Embodiments of the present invention include various mounting systems (referred to herein as “carriers”) on which multiple matched inertial sensors (e.g., gyroscopes or accelerometers) can be mounted in a fixed, optimized arrangement that allows for multiple-axis sensing, while maintaining the position of the inertial sensors over the life of the product.

Abstract: Microelectronic-device assemblies and methods are provided that enhance operation of microelectronic devices because they exclude extraneous elements from sensitive device areas. They are especially suited for devices that carry a plurality of bonding pads on a circuit face that has a sensitive area. A lead frame defines a paddle that has an area less than that of the device face. The paddle is spaced from the face and positioned to cover the sensitive area and expose the pads. A plastic ring is arranged to surround the sensitive area and abut the face and the paddle. Encapsulation in an overmold thus forms a void within the ring and between the device face and the paddle and extraneous elements are excluded from this void.

Abstract: A stress relief substrate having a pair of ball grid arrays (BGAs) is interposed between a PC board and an electrical component. The BGAs are electrically connected through vias in the stress relief substrate to connect component circuitry to the PC board. In one embodiment, the BGAs are offset on a flexible substrate so that there is some open space between the edges of electrically connected solder balls. This allows the substrate to warp during thermal cycling and absorb the stress caused by TCE mismatch. In another embodiment, the BGAs are aligned on a rigid substrate that is formed with holes interposed between the solder balls. This reduces the amount of material that interconnects the solder balls so that the substrate tends to flex rather than transfer the TCE stress to the solder balls.

Abstract: A test socket for a surface mount IC chip includes an array of double-ended spring contacts that extend out from opposite sides of a substrate, with a positioning frame on top of the substrate for aligning a chip and its leads with the upper contact heads. The spring contacts preferably have hollow elongate bodies with contact heads extending out from opposite sides under an internal spring bias. The socket can be formed from two laminates which have a series of aligned openings for the spring contacts, with expanded midsections on the spring contacts press-fit into the laminate openings and thereby securing holding the laminates together. A standoff on the upper socket surface vertically positions the IC chip, and provides the proper contact pressure between its leads and the spring contacts. The test socket can be removably mounted to a PC test board, with a releasable clamping device such as an air cylinder used to hold a chip to be tested in place within the socket.

Abstract: A wet etching process wherein the etchant bath is ultrasonically vibrated, preferably while a carrier member holding the workpiece to be etched is slightly agitated. An apparatus for practicing the process includes a first vessel for holding a coupling fluid; a second vessel for holding an etchant solution; means for suspending the second vessel in the coupling fluid of the first vessel; and an ultrasonic generator means coupled to the first vessel to impart ultrasonic vibrations to the coupling fluid and, via the coupling fluid and second vessel, to the etchant solution.

Abstract: A wet etching process wherein the etchant bath is ultrasonically vibrated, preferably while a carrier member holding the workpiece to be etched is slightly agitated. An apparatus for practicing the process includes a first vessel for holding a coupling fluid; a second vessel for holding an etchant solution; means for suspending the second vessel in the coupling fluid of the first vessel; and an ultrasonic generator means coupled to the first vessel to impart ultrasonic vibrations to the coupling fluid and, via the coupling fluid and second vessel, to the etchant solution.