Abstract: The invention is directed to a device for obtaining flow rate measurements including a sensor assembly and a housing. The sensor assembly includes a body defining a first fluid flow passage having an inlet, an outlet, a flow restricting element in the first fluid flow passage between the inlet and the outlet, an upstream fluid pressure sensor, a downstream fluid pressure sensor, an upstream signal contact connected to the upstream fluid pressure sensor, and a downstream signal contact connected to the downstream fluid pressure sensor. The housing has an upstream portion defining an upstream port, a downstream portion defining a downstream port, and a probe access port configured to provide access of a probe to at least one of the upstream signal contact and downstream signal contact. The housing can also define a second fluid flow passage in parallel with the first fluid flow passage. The device can be disposable.

Abstract: In a cosed-loop process, a controller uses a flow sensor to monitor the flow of a medicinal fluid being infused into a patient, to achieve a desired rate of flow. A relatively inexpensive peristaltic pump or electronically controlled valve can be used to vary the flow of the medicinal fluid through a fluid line. A Y site within the fluid line includes an integral flow sensor having an orifice. The flow sensor includes proximal and distal pressure sensors disposed on opposite sides of the orifice to monitor the distal and proximal pressure, producing a signal indicative of the rate of flow of the medicinal fluid through the fluid line. A signal produced by the controller is input to a motor driving the pump or to the valve to vary the rate of flow as required to achieve the desired infusion rate of the medicinal fluid.

Abstract: The present invention provides a microneedle incorporating a base that is broad relative to a height of the microneedle, to minimize breakage. The microneedle further includes a fluid channel and a beveled non-coring tip. Preferably arrays of such microneedles are fabricated utilizing conventional semiconductor derived micro-scale fabrication techniques. A dot pattern mask is formed on an upper surface of a silicon substrate, with each orifice of the dot pattern mask corresponding to a desired location of a microneedle. Orifices are formed that pass completely through the substrate by etching. A nitride pattern mask is formed to mask all areas in which a nitride layer is not desired. A nitride layer is then deposited on the bottom of the silicon substrate, on the walls of the orifice, and on the top of the silicon substrate around the periphery of the orifice. The nitride layer around the periphery of the orifice is offset somewhat, such that one side of the orifice has a larger nitride layer.

Abstract: The invention is directed to a device for obtaining flow rate measurements including a sensor assembly and a housing. The sensor assembly includes a body defining a first fluid flow passage having an inlet, an outlet, a flow restricting element in the first fluid flow passage between the inlet and the outlet, an upstream fluid pressure sensor, a downstream fluid pressure sensor, an upstream signal contact connected to the upstream fluid pressure sensor, and a downstream signal contact connected to the downstream fluid pressure sensor. The housing has an upstream portion defining an upstream port, a downstream portion defining a downstream port, and a probe access port configured to provide access of a probe to at least one of the upstream signal contact and downstream signal contact. The housing can also define a second fluid flow passage in parallel with the first fluid flow passage. The device can be disposable.

Abstract: The invention is directed to a device for obtaining flow rate measurements including a sensor assembly and a housing. The sensor assembly includes a body defining a first fluid flow passage having an inlet, an outlet, a flow restricting element in the first fluid flow passage between the inlet and the outlet, an upstream fluid pressure sensor, a downstream fluid pressure sensor, an upstream signal contact connected to the upstream fluid pressure sensor, and a downstream signal contact connected to the downstream fluid pressure sensor. The housing has an upstream portion defining an upstream port, a downstream portion defining a downstream port, and a probe access port configured to provide access of a probe to at least one of the upstream signal contact and downstream signal contact. The housing can also define a second fluid flow passage in parallel with the first fluid flow passage. The device can be disposable.

Abstract: The invention is directed to a device for obtaining flow rate measurements including a sensor assembly and a housing. The sensor assembly includes a body defining a first fluid flow passage having an inlet, an outlet, a flow restricting element in the first fluid flow passage between the inlet and the outlet, an upstream fluid pressure sensor, a downstream fluid pressure sensor, an upstream signal contact connected to the upstream fluid pressure sensor, and a downstream signal contact connected to the downstream fluid pressure sensor. The housing has an upstream portion defining an upstream port, a downstream portion defining a downstream port, and a probe access port configured to provide access of a probe to at least one of the upstream signal contact and downstream signal contact. The housing can also define a second fluid flow passage in parallel with the first fluid flow passage. The device can be disposable.

Abstract: The present invention provides a microneedle incorporating a base that is broad relative to a height of the microneedle, to minimize breakage. The microneedle further includes a fluid channel and a beveled non-coring tip. Preferably arrays of such microneedles are fabricated utilizing conventional semiconductor derived micro-scale fabrication techniques. A dot pattern mask is formed on an upper surface of a silicon substrate, with each orifice of the dot pattern mask corresponding to a desired location of a microneedle. Orifices are formed that pass completely through the substrate by etching. A nitride pattern mask is formed to mask all areas in which a nitride layer is not desired. A nitride layer is then deposited on the bottom of the silicon substrate, on the walls of the orifice, and on the top of the silicon substrate around the periphery of the orifice. The nitride layer around the periphery of the orifice is offset somewhat, such that one side of the orifice has a larger nitride layer.

Abstract: The present invention provides a microneedle incorporating a base that is broad relative to a height of the microneedle, to minimize breakage. The microneedle further includes a fluid channel and a beveled non-coring tip. Preferably arrays of such microneedles are fabricated utilizing conventional semiconductor derived micro-scale fabrication techniques. A dot pattern mask is formed on an upper surface of a silicon substrate, with each orifice of the dot pattern mask corresponding to a desired location of a microneedle. Orifices are formed that pass completely through the substrate by etching. A nitride pattern mask is formed to mask all areas in which a nitride layer is not desired. A nitride layer is then deposited on the bottom of the silicon substrate, on the walls of the orifice, and on the top of the silicon substrate around the periphery of the orifice. The nitride layer around the periphery of the orifice is offset somewhat, such that one side of the orifice has a larger nitride layer.

Abstract: In a closed-loop process, a controller uses a flow sensor to monitor the flow of a medicinal fluid being infused into a patient, to achieve a desired rate of flow. A relatively inexpensive peristaltic pump or electronically controlled valve can be used to vary the flow of the medicinal fluid through a fluid line. A Y site within the fluid line includes an integral flow sensor having an orifice. The flow sensor includes proximal and distal pressure sensors disposed on opposite sides of the orifice to monitor the distal and proximal pressure, producing a signal indicative of the rate of flow of the medicinal fluid through the fluid line. A signal produced by the controller is input to a motor driving the pump or to the valve to vary the rate of flow as required to achieve the desired infusion rate of the medicinal fluid.

Abstract: In a closed-loop process, a controller uses a flow sensor to monitor the flow of a medicinal fluid being infused into a patient, to achieve a desired rate of flow. A relatively inexpensive peristaltic pump or electronically controlled valve can be used to vary the flow of the medicinal fluid through a fluid line. A Y site within the fluid line includes an integral flow sensor having an orifice. The flow sensor includes proximal and distal pressure sensors disposed on opposite sides of the orifice to monitor the distal and proximal pressure, producing a signal indicative of the rate of flow of the medicinal fluid through the fluid line. A signal produced by the controller is input to a motor driving the pump or to the valve to vary the rate of flow as required to achieve the desired infusion rate of the medicinal fluid.

Abstract: Methods and structures are provided which support spacer walls in a position which facilitates installation of the spacer walls between a faceplate structure and a backplate structure of a flat panel display. In one embodiment, spacer feet are formed at opposing ends of the spacer wall. These spacer feet can be formed of materials such as ceramic, glass and/or glass frit. The spacer feet support the corresponding spacer wall on the faceplate (or backplate) structure. Tacking electrodes can be provided on the faceplate (or backplate) structure to assert an electrostatic force on the spacer feet, thereby holding the spacer feet in place during installation of the spacer wall. The spacer wall can be mechanically and/or thermally expanded prior to attaching both ends of the spacer wall to the faceplate (or backplate) structure. The spacer wall is then allowed to contract, thereby introducing tension into the spacer wall which tends to straighten any inherent waviness in the spacer wall.

Abstract: The present invention provides a microneedle incorporating a base that is broad relative to a height of the microneedle, to minimize breakage. The microneedle further includes a fluid channel and a beveled non-coring tip. Preferably arrays of such microneedles are fabricated utilizing conventional semiconductor derived micro-scale fabrication techniques. A dot pattern mask is formed on an upper surface of a silicon substrate, with each orifice of the dot pattern mask corresponding to a desired location of a microneedle. Orifices are formed that pass completely through the substrate by etching. A nitride pattern mask is formed to mask all areas in which a nitride layer is not desired. A nitride layer is then deposited on the bottom of the silicon substrate, on the walls of the orifice, and on the top of the silicon substrate around the periphery of the orifice. The nitride layer around the periphery of the orifice is offset somewhat, such that one side of the orifice has a larger nitride layer.

Abstract: A micro-machined absolute pressure sensor and process for making the same. A semiconductor membrane having a welled portion connected to a planar periphery is formed in recess in a silicon substrate through etching and boron diffusion. A dielectric pad is formed on a portion of the planar periphery, and a bonding layer of polysilicon or amorphous silicon is deposited over the semiconductor membrane and the dielectric pad. After an etching process that defines the outline of the semiconductor membrane, the bonding layer is bonded to a nonconductive substrate in a vacuum using electrostatic bonding or wafer bonding, forming a vacuum-sealed reference cavity. A first and a second conductor are disposed on an upper surface of the nonconductive substrate. The first conductor serves as a capacitor plate disposed within the reference cavity and is connected to a transfer lead that passes from the cavity. The transfer lead is electrically isolated from the semiconductor membrane by the dielectric pad.

Abstract: A monolithic flow controller for controlling the rate at which a medicinal liquid is administered to a patient. The monolithic flow controller includes one or more virtual valves that, because of their relatively small opening size (less than 0.5 &mgr;m in diameter), only permit fluid to flow through the valve when a forward bias voltage is applied. If a reverse bias voltage or no voltage is applied, fluid flow through the opening is inhibited. The fluid rate through the device is monitored using two pressure sensors or a differential pressure sensor that determine the differential pressure along the flow path through the device or relative to the external ambient pressure. The flow through the device is equal to the product of the differential pressure and the conductance of the channel in the flow controller. A capacitive bubble sensor is optionally provided to detect bubbles in the medicinal liquid being administered to the patient.

Abstract: Methods and structures are provided which support spacer walls in a position which facilitates installation of the spacer walls between a faceplate structure and a backplate structure of a flat panel display. In one embodiment, spacer feet are formed at opposing ends of the spacer wall. These spacer feet can be formed of materials such as ceramic, glass and/or glass frit. The spacer feet support the corresponding spacer wall on the faceplate (or backplate) structure. Tacking electrodes can be provided on the faceplate (or backplate) structure to assert an electrostatic force on the spacer feet, thereby holding the spacer feet in place during installation of the spacer wall. The spacer wall can be mechanically and/or thermally expanded prior to attaching both ends of the spacer wall to the faceplate (or backplate) structure. The spacer wall is then allowed to contract, thereby introducing tension into the spacer wall which tends to straighten any inherent waviness in the spacer wall.

Abstract: A spacer (100 or 600/1000A/1000B) situated between a faceplate structure (301) and a backplate structure (302) of a flat panel display is configured to be self standing. In one implementation, a pair of spacer feet (111 or 113 and 112 or 114) are located over the same face surface, or over opposite face surfaces, of a spacer wall (101) near opposite ends of the wall. An edge electrode (121 or 122) is located over an edge surface of the spacer adjacent to the faceplate structure or the backplate structure. In another implementation, a spacer clip (1000A or 1000B) clamps opposite face surfaces of a spacer wall (600) largely at one end of the wall.

Abstract: A process for manufacturing a vacuum enclosure for a semiconductor device formed on a substrate with leads extending peripherally. Assembly of the enclosure is compatible with known batch fabrication techniques and is carried out at pressures required for optimal device operation. In a first embodiment, an intrinsic silicon shell is sealed to the substrate via electrostatic or anodic bonding with the leads diffusing into the shell. In a second embodiment, a thin interface layer of silicon or polysilicon is deposited on the substrate prior to electrostatic bonding a glass shell thereon. In a third embodiment, tunnels are formed between a lower peripheral edge of the shell and the substrate, allowing leads to pass thereunder. The tunnels are sealed by a dielectric material applied over the enclosure.

Abstract: A micromechanical contact load force sensor is disclosed. The force sensor comprises an array of capacitive load cells on a substrate. The force sensor is able to sense high loads, on the order on 10.sup.9 N/m.sup.2, and distribute the load over a suitable number of the cells of the array while minimizing crosstalk between adjacent cells. The force sensor is useful in biological and robotic applications.

Abstract: A micromechanical tuning fork gyroscope fabricated by a dissolved silicon wafer process whereby electrostatic bonding forms a hermetic seal between an etched glass substrate, metal electrodes deposited thereon, and a silicon comb-drive tuning fork gyroscope. The dissolved silicon wafer process involves single sided processing of a silicon substrate, including the steps of etching recesses, diffusing an etch resistant dopant into the silicon substrate, and releasing various components of the silicon gyroscope by etching through the diffusion layer in desired locations. The glass substrate also undergoes single sided processing, including the steps of etching recesses, depositing a multi-metal system in the recesses, and selectively etching portions of the multi-metal system. One substrate is inverted over the other and aligned before anodic bonding of the two substrates is performed.

Abstract: A high-performance switched-capacitor circuit for electronic read-out of a pressure sensor-based ultrasensitive microflow transducer. The microflow transducer uses a differential capacitive pressure sensor to measure flow. Read-out electronics associated with the transducer feature a clocking speed of 100 KHz and drive loads up to 35 pF. The read-out electronics include a high DC gain that nulls out stray input capacitance, which is beneficial for the multichip realization of the microflow transducer disclosed herein. The uncompensated linearity of the overall read-out electronics is 10 bits, and the pressure/flow resolution is 12 bits. An ultrasensitive membrane associated with the pressure sensor does not respond to a pulsed waveform for frequencies above 50 KHz. But for lower frequencies, it deflects in response to the time-average voltage applied across the capacitor plates of the pressure sensor. A self-test mode is provided which employs an extremely long pre-charge pulse.