Abstract: An ion source for an analytical instrument is described. The ion source comprises a capillary tip and counter-electrode interface and a feedback loop control device connected to the capillary tip and counter-electrode interface. The feedback loop control device comprises a transimpedance amplifier, a DC de-coupler, a frequency to voltage converter, a controller, and a voltage-controlled high-voltage power supply that provides a tip to counter-electrode voltage to the capillary tip and counter-electrode interface. The feedback loop control device measures the modulation frequency of ionization currents and provides a feedback adjustment of the tip-to-counter-electrode voltage to maintain ionization efficiency.

Abstract: A microfluidic structure having an electrostatic sealing device is disclosed. The electrostatic sealing device includes a first electrode and a second electrode opposite the first electrode. At least one of the electrodes has an elastic layer facing the other electrode. The second electrode is capable of moving toward the first electrode and forming a seal with the first electrode in response to a voltage difference between the two electrodes. The electrostatic sealing device eliminates the need for mechanical components that are traditionally used for generating a mechanical force between two components of a microfluidic structure and thus reduces complexity of the microfluidic structure and possible interference with optical interrogation of the microfluidic structure. Moreover, the seal can be established or removed simply by turning the voltage on or off.

Abstract: The fluid flow rate within a microfluidic passageway of a microfabricated device is determined by measuring the time-of-flight of a heat pulse coupled into the fluid. Since the propagation velocity of the heat trace is generally slower than the mean flow rate of the flow, additional processing provides the appropriate scaling needed to obtain an accurate fluid flow rate measurement. The scaling factor is based on the geometry of the structure and the thermal properties of the fluid and the materials used for the device.

Abstract: The present invention relates to a microfluidic device for separating the components of a fluid sample. A cover plate is arranged over the first surface of a substrate, which, in combination with a microchannel formed in the first surface, defines a separation conduit for separating the components of the fluid sample. An inlet port in fluid communication with the separation conduit allows a mobile phase containing a gradient of a selected mobile-phase component to be introduced from an integrated gradient-generation means to the separation conduit. A method is also provided for separating the components of a fluid sample using a mobile phase containing a gradient of a selected mobile-phase component, wherein the gradient is generated within a small volume of mobile phase.

Abstract: An erase operation is performed on a non-volatile memory cell with an oxide-nitride-oxide structure by using a negative gate erase voltage during an erase procedure to improve the speed and performance of the non-volatile memory cell after many program-erase cycles. During the erase procedure, an erase cycle is applied followed by a read cycle until the cell has a threshold erased below a desired value. For the initial erase cycle in the procedure, an initial negative gate voltage is applied. In subsequent erase cycles, a sequentially decreasing negative gate voltage is applied until the threshold is reduced below the desired value. In one embodiment, after erase is complete, the last negative gate voltage value applied is stored in a separate memory. After a subsequent programming when the erase procedure is again applied, the initial negative gate voltage applied is the negative gate voltage value for the cell stored in memory.

Abstract: A programming operation using hot carrier injection is performed on a non volatile memory cell having an oxide-nitride-oxide structure by applying a first train of voltage pulses to he drain and a second train of voltage pulses to the gate. The programming method of the present invention prevents over-programming, minimizes programming time, and increases memory cell endurance and reliability.

Abstract: A method of manufacturing a flash memory device with a controllable amount of gate edge lifting including etching the ends of the tunnel oxide forming a cavity at each end of the tunnel oxide and anisotropically depositing and etching an oxide to form spacers on the sides of the gate stack. The spacers have a predetermined thickness that controls the amount of gate edge lifting. The predetermined thickness is determined during a characterization procedure that can be a computer modeling procedure or it can be determined empirically.

Abstract: A method of programming a memory cell with a substrate that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes applying a constant first voltage across the gate, applying a second constant voltage across the first region and applying a third voltage that is constant and negative to the substrate so that the effect of spillover electrons is substantially reduced when compared with when the third constant voltage is absent.

Abstract: A system and method for providing a memory cell on a semiconductor is disclosed. In one aspect, the method and system include providing at least one gate stack on the semiconductor, depositing at least one spacer, and providing at least one source implant in the semiconductor. The at least one gate stack has an edge. A portion of the at least one spacer is disposed along the edge of the at least one gate stack. In another aspect, the method and system include providing at least one gate stack on the semiconductor, providing a first junction implant in the semiconductor, depositing at least one spacer, and providing a second junction implant in the semiconductor after the at least one spacer is deposited. The at least one gate stack has an edge. A portion of the at least one spacer is disposed at the edge of the at least one gate stack.

Abstract: An erase operation is performed on a non-volatile memory cell with an oxide-nitride-oxide structure by using an initial negative gate erase voltage to improve the speed and performance of the non-volatile memory cell after many program-erase cycles. By utilizing a negative gate erase voltage, the cell does not require increased erase time to reduce the cell threshold and avoid incomplete erase conditions as the number of program-erase cycles increases.

Abstract: A method of selectively erasing an individual memory cell of an array of non-volatile memory cells by providing an array of non-volatile memory cells that includes a first non-volatile memory cell that is connected in series with a second non-volatile memory cell and erasing the first non-volatile memory cell while not erasing the second non-volatile memory cell.

Abstract: An erase operation is performed on a non-volatile memory cell with an oxide-nitride-oxide structure having charge stored near both the source and drain. During the erase operation, a negative gate erase voltage is applied along with a positive source and drain voltage to improve the speed of erase operations and performance of the non-volatile memory cell after many program-erase cycles.

Abstract: A method for making a ULSI MOSFET chip includes forming a MOSFET gate stack on a substrate, with a tunnel oxide layer being sandwiched between the gate stack and substrate. To prevent thickening of the tunnel oxide layer into a “gate edge lifting” profile during subsequent oxidation-causing steps, at least one protective barrier film is deposited or grown over the gate stack and tunnel oxide layer immediately after gate stack formation. Then, subsequent steps, including forming source and drain regions for the gate stack, can be undertaken without causing thickening of the tunnel oxide layer.

Abstract: A method of erasing a memory cell that includes a first region and a second region with a channel therebetween and a gate above the channel, and a charge trapping region that contains a first amount of charge. The method includes: applying a voltage across the gate and the first region in accordance with a coarse erase sequence of voltages so that a portion of the first amount of charge is removed from the charge trapping region; and applying a voltage across the gate and the first region in accordance with a fine erase sequence of voltages so that a portion of the first amount of charge is removed from the charge trapping region.

Abstract: A system and method for controlling a characteristic of at least one memory cell on a semiconductor is disclosed. The at least one memory cell includes a gate stack, a source, and a drain. The semiconductor includes a surface. In one aspect, the method and system include providing the gate stack on the semiconductor and providing the source including a source dopant having a local peak in concentration. The local peak in concentration of the source dopant is located under the gate stack and in proximity to a portion of the surface of the semiconductor. In another aspect the method and system includes a memory cell on a semiconductor. The semiconductor includes a surface. The memory cell includes a gate stack on the semiconductor, a source, and a drain. The gate stack has a first edge and a second edge. The source is located in proximity to the first edge of the gate stack. The drain is located in proximity to the second edge of the gate stack. A first portion of the source is disposed under the gate stack.

Abstract: The method of fabricating the semi-conductor device includes forming a center dielectric region on a substrate. The center dielectric region has a first thickness and the substrate includes a first conductive material. Then, a first plurality of spacers is formed near the center dielectric region. A second conductive material is implanted into the substrate using the first plurality of spacers for alignment. The second conductive material form sources/drains the first plurality of spacers are then removed and a dielectric layer is formed over the substrate and the source/drain regions. The dielectric layer has a second thickness that is less than the first thickness. A second plurality of spacers is formed near the center dielectric region. The second plurality of spacers are conductive and have a third thickness that is substantially equal to the difference of the first and second thickness'. A gate dielectric layer is formed over the substrate, center dielectric region, and second plurality of spacers.

Abstract: A flash memory device and a method of manufacturing the flash memory device having high reliability in which a gate stack is formed on a tunnel oxide formed on a substrate and a layer of oxide is formed on the surfaces of the gate stack and exposed surfaces of the substrate. Nitrogen is diffused into the layer of oxide.

Abstract: A memory cell that includes a substrate that has a first region and a second region with a channel therebetween, wherein the first region generates hot carriers. The memory cell further includes a gate above the channel and a charge trapping region that contains a first amount of charge. A current limiter that limits the number of the generated hot carriers that can flow into the channel, wherein the current limiter does not control the voltage of the second region.

Abstract: A method for making a ULSI MOSFET chip includes forming a MOSFET gate stack on a substrate, with a tunnel oxide layer being sandwiched between the gate stack and substrate. To prevent thickening of the tunnel oxide layer into a “gate edge lifting” profile during subsequent oxidation-causing steps, at least one protective barrier film is deposited or grown over the gate stack and tunnel oxide layer immediately after gate stack formation. Then, subsequent steps, including forming source and drain regions for the gate stack, can be undertaken without causing thickening of the tunnel oxide layer.

Abstract: A method of manufacturing a flash memory device in which minimal gate edge lifting is accomplished by etching a portion of the ends of the layer of tunnel oxide forming cavities, forming silicon nitride plugs in the cavities and forming a layer of oxide on the surface of the flash memory device wherein the silicon nitride plugs minimize gate edge lifting.