Abstract: A process for forming a junction-isolated, electrically conductive via in a silicon substrate and a conductive apparatus to carry electrical signal from one side of a silicon wafer to the other side are provided. The conductive via is junction-isolated from the bulk of the silicon substrate by diffusing the via with a dopant that is different than the material of the silicon substrate. Several of the junction-isolated vias can be formed in a silicon substrate and the silicon wafer coupled to a second silicon substrate of a device that requires electrical connection. This process for forming junction-isolated, conductive vias is simpler than methods of forming metallized vias, especially for electrical devices more tolerant of both resistance and capacitance.

Abstract: A differential variable capacitance acceleration sensor includes a sandwich structure having three stacked plates of silicon with the center plate mounted such that its center portion is enabled to move in a sealed cavity with each side thereof moving toward and away from a fixed cooperating plate forming the opposite side of a capacitive circuit. The center portion or mass of the center plate is suspended from its rim by means of a large number of integral fingers extending from the rim to the top and bottom surfaces of the center portion. This center mass includes a number of through holes to permit the passage of air from one side to the other and may also include grooves to aid in the flow of air. The fixed top plate or lid and the base also have, or may have, grooves to assist in the passage of air. An alternative embodiment includes a smaller number of more compliant fingers to provide a more compliant structure.

Abstract: A strain sensitive element for use in a system for converting mechanical movement of relatively movable portions of the element into electrical signals, includes a substantially planar substrate comprising an N-type silicon crystal material wherein the substrate includes one or more grooves extending into the substrate defining an integral hinge portion between at least two relatively movable parts. At least one unitary strain gage extends across a groove without any separate support so that the strain gage and the hinge portion are spaced apart. The strain gage is a unitary member derived from the same silicon crystal material of the substrate and comprises P-type silicon material. The strain gage is joined to two of the relatively movable parts of the substrate. At least one unitary conductor extends across a groove without separate support so that the conductor and the hinge portion are spaced apart.

Abstract: A strain sensitive element for use in a system for converting mechanical movement of relatively movable portions of the element into electrical signals, includes a substantially planar substrate comprising an N-type silicon crystal material wherein the substrate includes groove means extending into the substrate defining an integral hinge portion between at least two relatively movable parts. At least one unitary strain gage extends across the groove means without any separate support so that the strain gage and the hinge portion are spaced apart. The strain gage is a unitary member derived from the same silicon crystal material of the substrate and comprises P-type silicon material. The strain gage is joined to two of the relatively movable parts of the substrate. At least one unitary conductor extends across the groove means without separate support so that the conductor and the hinge portion are spaced apart.

Abstract: A strain sensitive element for use in a system for converting mechanical movement of portions of the element which are movable relative to each other into electrical signals, includes a planar substrate including an N-type silicon material wherein the substrate includes grooves extending into the substrate defining an integral hinge portion between at least two relatively movable parts. At least one strain gage extends across a groove without any separate support so that the strain gage and the hinge portion are spaced apart. The strain gage is joined to two of the relatively movable parts of the substrate. At least one elongate frangible link extends across a concave pit in the substrate. The frangible link is derived from the same silicon material as the substrate. The midportion of the frangible link is spaced from the lower surface of the pit and the end portions of the frangible link are joined to the substrate. At least one resistor is provided.

Abstract: A structure is provided, such as a capacitive transducer, utilizing two or more layers of semiconductor material wherein a highly insulating low capacitance bond is achieved by the invention herein between two adjacent layers by forming an inlay of glass in one layer and anodically bonding the other layer to the polished surface of the previously formed inlay.

Abstract: An electromechanical transducer is provided, and the process for making it, which utilizes a piezoresistive element or gage which is crystallinally the same as the base or substrate upon which it is supported. The gage of the invention is a force gage, and is derived from its substrate by etching in a series of steps which, ultimately, provide a gage with substantially reduced strain energy requirements, because the volume of the gage may be as small as 3.times.10.sup.10 cubic centimeters of stressed material. In its most preferred form, the element or gage is etched free of its substrate to provide, in effect, a "floating gage." This is achieved by defining the gage in its substrate or in material rigidly bonded to its substrate, etching away immediately adjacent material, and leaving the gage free in space, while supported at each end on the substrate.

Abstract: A capacitive transducer is provided having a plate mounted therein to move in a piston-like manner in a sealed cavity toward and away from a fixed cooperating plate forming the other side of the capacitive circuit. The movable plate is etched in a unique fashion from a single crystal silicon wafer in a batch process forming a plurality of capacitive sensors simultaneously. The movable plate is etched in unique fashion with a plurality of spaced passages, allowing passage of fluid such as air contained in the cavity therethrough, thus damping plate movement by such fluids. The surfaces of the plate are further etched with special grooves to direct fluid flow to the passages. Moreover, a plurality of spaced stops are included in the plate surface during the etching process to overcome both electrostatic latch-up, wherein electrical attraction exceeds membrane restoring force, and pneumatic latch-up, wherein membrane restoring force is inadequate to draw gas between plates in close proximity.

Abstract: An electromechanical transducer is provided, and the process for making it, which utilizes a piezoresistive element or gage which is crystallinally the same as the base or substrate upon which it is supported. The gage of the invention is a force gage, and is derived from its substrate by etching in a series of steps which, ultimately, provide a gage with substantially reduced strain energy requirements, because the volume of the gage may be as small as 33.times.10.sup.10 cubic centimeters of stressed material. In its most preferred form, the element or gage is etched free of its substrate to provide, in effect, a "floating gage. " This is achieved by defining the gage in its substrate or in material rigidly bonded to its substrate, etching away immediately adjacent material, and leaving the gage free in space, while supported at each end on the substrate.

Abstract: The invention is concerned with a pressure diaphragm that is composed of a nonmetallic material that has been sculptured by etching a plate to form thick motes, or islands, and a thick rim interconnected by thin sheet material. The thick portions are separated by thin flexures in which the deflection of the diaphragm is concentrated, whereby the deflection yields a high value of electric output per unit pressure.

Abstract: A diaphragm for a miniature pressure transducer has its surface sculptured by anisotropic etching to provide gauge areas in the form of narrow thin flexure areas between thick areas in the form of islands or motes. The thick areas act to constrain or stiffen the flexure areas from bending along their lengths while facilitating the bending thereof about axes parallel to their lengths when the diaphragm deflects in response to a pressure change. Linear piezoresistive gauges diffused into the gauge areas are responsive to the bending of said flexure areas to change resistance by an amount corresponding to the pressure change.