Abstract: An inductor has a spiral aluminum track deposited on an oxide layer over a silicon substrate. The substrate is etched away to form a trench, which extends around beneath the track and provides an air gap having a low dielectric constant. The oxide layer has an inner region within the track, an outer region outside the track and a bridging region extending between the other regions. The bridging region is comprised of intact bridges and gaps therebetween, which are open to the trench and through which an etchant has access to the silicon substrate to form the trench by etching.

Abstract: The invention describes a thermal cycler which permits simultaneous treatment of multiple individual samples in independent thermal protocols, so as to implement large numbers of DNA experiments simultaneously in a short time. The chamber is thermally isolated from its surroundings, heat flow in and out of the unit being limited to one or two specific heat transfer areas. All heating elements are located within these transfer areas and at least one temperature sensor per heating element is positioned close by. Fluid bearing channels that facilitate sending fluid into, and removing fluid from, the chamber are provided. The chambers may be manufactured as integrated arrays to form units in which each cycler chamber has independent temperature and fluid flow control Two embodiments of the invention are described together with a process for manufacturing them.

Abstract: The present invention significantly reduces charging effects in electrostatic devices due to charge accumulation in or on the insulating materials on the active surfaces of the devices. This has been achieved by replacing the dielectric material that is normally present between the force generating conductor surfaces with a semi-insulating material. This semi-insulating film overcomes the effects of charging, while avoiding short-circuits when the surfaces are pulled into contact. It is not subject to insulation breakdown within the range of voltages used to operate the device. Examples of semi-insulating materials that may be used are semi-insulating polysilicon (SIPOS) and silicon rich silicon nitride.

Abstract: A method for forming bonds between similar and dissimilar material surfaces, particularly the surfaces of silicon wafers having various devices disposed thereon, wherein such bonds can be formed at room temperature and do not require the application of high pressures or voltages. The bonding material is polydimethylsiloxane, which is transparent and bio-compatible.

Abstract: A process has been described which makes use of polysilicon beam as the structural material instead of single crystal silicon for the fabrication of MEMS sensors/actuators. The invention describes the process for fabricating suspended polysilicon beams by using deep trenches etched into silicon substrate as a kind of a mould to form polysilicon beams. The polysilicon beams are subsequently released by isotropically etching away the silicon surrounding the polysilicon beams. This results in free standing polysilicon members, which form the MEMS structures. In addition to the general process, three approaches to making electrical contact to the beams are presented.

Abstract: The present invention significantly reduces charging effects in electrostatic devices due to charge accumulation in or on the insulating materials on the active surfaces of the devices. This has been achieved by replacing the dielectric material that is normally present between the force generating conductor surfaces with a semi-insulating material. This semi-insulating film overcomes the effects of charging, while avoiding short-circuits when the surfaces are pulled into contact. It is not subject to insulation breakdown within the range of voltages used to operate the device. Examples of semi-insulating materials that may be used are semi-insulating polysilicon (SIPOS) and silicon rich silicon nitride.

Abstract: The invention describes a thermal cycler which permits simultaneous treatment of multiple individual samples in independent thermal protocols, so as to implement large numbers of DNA experiments simultaneously in a short time. The chamber is thermally isolated from its surroundings, heat flow in and out of the unit being limited to one or two specific heat transfer areas. All heating elements are located within these transfer areas and at least one temperature sensor per heating element is positioned close by. Fluid bearing channels that facilitate sending fluid into, and removing fluid from, the chamber are provided. The chambers may be manufactured as integrated arrays to form units in which each cycler chamber has independent temperature and fluid flow control. Two embodiments of the invention are described together with a process for manufacturing them.

Abstract: The invention describes a thermal cycler which permits simultaneous treatment of multiple individual samples in independent thermal protocols, so as to implement large numbers of DNA experiments simultaneously in a short time. The chamber is thermally isolated from its surroundings, heat flow in and out of the unit being limited to one or two specific heat transfer areas. All heating elements are located within these transfer areas and at least one temperature sensor per heating element is positioned close by. Fluid bearing channels that facilitate sending fluid into, and removing fluid from, the chamber are provided. The chambers may be manufactured as integrated arrays to form units in which each cycler chamber has independent temperature and fluid flow control. Two embodiments of the invention are described together with a process for manufacturing them.

Abstract: An inductor has a spiral aluminum track deposited on an oxide layer over a silicon substrate. The substrate is etched away to form a trench, which extends around beneath the track and provides an air gap having a low dielectric constant. The oxide layer has an inner region within the track, an outer region outside the track and a bridging region extending between the other regions. The bridging region is comprised of intact bridges and gaps therebetween, which are open to the trench and through which an etchant has access to the silicon substrate to form the trench by etching.

Abstract: The present invention is a motion sensor apparatus for use as a general mechanical amplifier, a gyroscope, or other resonant sensor such as an accelerometer. In accordance with the invention, the motion sensor apparatus includes a primary mass and a primary flexure structure. The primary flexure structure supports the primary mass to experience driven motion against a bias of the primary flexure structure. The apparatus further includes a secondary mass which is less massive than the primary mass. A secondary flexure structure interconnects the secondary mass with the primary mass, and supports the secondary mass to experience sensing motion relative to the primary mass against a bias of the secondary flexure structure. The stiffness ratio between the primary and secondary flexure structures is equal to the mass ratio between the primary and secondary masses.

Abstract: A pressure sensor fabricated onto a substrate using conventional CMOS fabrication processes. The pressure sensor is built on a substrate having a first conductivity type and has defined in it a well of an opposite conductivity type. This well defines a membrane. Resistors are diffused into the well. Source/drain regions are provided for leadouts for the resistors. An n-cap is provided for the resistors. Metalization contacts may be provided to connect the membrane to a positive bias during a membrane etching process. A cavity is provided on the underside of the substrate through which pressure is applied to the membrane. Signal conditioning circuitry, such as an operational amplifier, may also be fabricated on the same substrate preferably using the same IC processes.

Abstract: A pressure sensor fabricated onto a substrate using conventional CMOS fabrication processes. The pressure sensor is built on a substrate having a first conductivity type and has defined in it a well of an opposite conductivity type. This well defines a membrane. Resistors are diffused into the well. Source/drain regions are provided for leadouts for the resistors. An n-cap is provided for the resistors. Metalization contacts may be provided to connect the membrane to a positive bias during a membrane etching process. A cavity is provided on the underside of the substrate through which pressure is applied to the membrane. Signal conditioning circuitry, such as an operational amplifier, may also be fabricated on the same substrate preferably using the same IC processes.

Abstract: A novel process for fabricating an integrated circuit sensor/actuator is described. Silicon islands are created by forming deep trenches in a substrate and lining the trenches with oxide. This forms silicon islands substantially surrounded by electrically isolating oxide. The anchor portion of the sensor/actuator beams is connected to the islands and is released from the substrate and therefore is also electrically isolated from the substrate. The IC sensor/actuator is manufactured by forming deep trenches in a substrate.

Abstract: A pressure sensor is provided in which the pressure sensing components are isolated from a portion of an attached buffer member which is connected to a fluid conduit. The offset characteristic of the pressure sensor isolates stress from being transmitted between an attached external fluid conduit and the sensitive components of the pressure sensor. One embodiment of the pressure sensor solders a fluid conduit structure to a buffer member that is attached to a pressure sensor die. An alternative embodiment of the present invention avoids the need for making solder connections between the sensor structure and external components by utilizing elastomeric conductors and pressure seals in association with the pressure sensor composite structure and first and second housing structures. These elastomeric conductors also provide improved stress isolation. The housing structures are used to compress to the seal and the elastomeric conductor against selected portions of the composite sensor.

Abstract: A method is provided for assuring good electrical contact between a power supply and appropriate regions of silicon wafers to assure proper etching during the micromachining of the silicon die locations on the wafer. A plurality of conductors are disposed in the interstices between rows and columns of die locations and each die location that is to be etched is provided with a conductive extension connecting its relevant region with one of the interstice conductors. A preselected number of die locations are dedicated to the purpose of providing conductive pads against which contacts of a power supply can be disposed. The many interconnections between the row interstice conductors and the column interstice conductors assures good electrical distribution across the entire surface of a first side of the wafer.

Abstract: Disclosed is a Hall effect element formed in a single crystal semiconductor chip with the direction of bias current flow aligned parallel with the <100> cyrstallographic direction and also parallel with edges of the chip. The orientation described is selected to minimize piezoresistive effects produced by packaging-induced physical stress on the semiconductor chip.

Abstract: The marginal adhesion of platinum to silicon nitride is a serious issue in the fabrication of microbridge mass air flow sensors. High temperature stabilization anneals (500.degree.-1000.degree. C.) are necessary to develop the properties and stability necessary for effective device operation. However, the annealing process results in a significant reduction in the already poor platinum/silicon nitride adhesion. Annealing at relatively high temperatures leads to the development of numerous structural defects and the production of non-uniform and variable sensor resistance values. The use of a thin metal oxide adhesion Layvr, approximately 20 To 100 angstromw in thickness is very effective in maintaining platinum adhesion to silicon nitride, and through the high temperature anneal sequence.