Abstract: A system and method for dividing a single mass flow into secondary flows of desired ratios to total flow. Each secondary flow line includes a pressure drop element, an absolute pressure sensor and a differential pressure sensor. The nonlinear relationship between flow and pressures can be transformed into a function of the absolute and differential pressures that has a linear relationship with the flow.

Abstract: Devices and methods for mass flow verification are provided. A mass flow verifier includes a chamber configured to receive a fluid, a critical flow nozzle upstream of the chamber, a chamber valve, a downstream valve, and a bypass valve. The chamber valve is configured to selectively enable fluid flow from the critical flow nozzle to the chamber. The downstream valve is configured to selectively enable fluid flow from the chamber to a downstream location. The bypass valve is configured to selectively enable fluid flow from the critical flow nozzle to a dump location. The mass flow verifier further includes a controller configured to verify flow rate of the fluid based on a rate of rise in pressure of the fluid as detected by a pressure sensor in the chamber.

Abstract: Mass flow controllers that can provide for improved bleeding time and can be manufactured with less complexity and cost are provided. A mass flow controller includes a body having a valve outlet bore defining a flow path and an adjustable valve configured to control flow of a gas through the flow path. A valve element includes an outlet orifice of the adjustable valve and is disposed within the bore. The mass flow controller further includes a pressure drop element disposed coaxially with the valve element within the bore. An upstream pressure sensor is configured to detect a pressure at a location in the flow path between the adjustable valve and the pressure drop element, and a controller is configured to determine a flow rate through the flow path based on pressure as detected by the upstream pressure sensor.

Abstract: Systems and methods for detecting a composition of a binary gas mixture are provided. Such methods and systems include, with a species-dependent mass flow meter, sensing a mass flow rate of a binary gas mixture comprising gases of differing gas correction factors and, with a species-independent pressure sensor, sensing a total pressure of the binary gas mixture. An output representative of a relative concentration of one gas of the binary gas mixture is provided. The relative concentration is determined as a function of the sensed mass flow rate and the sensed total pressure.

Abstract: A gas delivery system and associated method includes a flow channel, a control valve, a downstream pressure sensor, and a controller. The control valve controls flow of gas in the flow channel. The downstream pressure sensor, located downstream of the control valve, measures gas pressure in the flow channel. The controller has an external trigger input to receive a trigger signal applied to a shutoff valve downstream from the control valve. The controller operates in separate modes based on a state of the trigger signal. In a non-triggered mode, the controller controls pressure at the pressure sensor via the control valve in accordance with a first gain schedule. In the triggered mode, the controller controls the pressure at the pressure sensor via the control valve in accordance with a second gain schedule that is distinct from the first gain schedule.

Abstract: A system and method provides a more precise mole delivery amount of a process gas, for each pulse of a pulse gas delivery, by measuring a concentration of the process gas and controlling the amount of gas mixture delivered in a pulse of gas flow based on the received concentration of the process gas. The control of mole delivery amount for each pulse can be achieved by adjusting flow setpoint, pulse duration, or both.

Abstract: A system and method for dividing a single mass flow into secondary flows of desired ratios to total flow. Each secondary flow line includes a pressure drop element, an absolute pressure sensor and a differential pressure sensor. The nonlinear relationship between flow and pressures can be transformed into a function of the absolute and differential pressures that has a linear relationship with the flow.

Abstract: A system and method provides a more precise mole delivery amount of a process gas, for each pulse of a pulse gas delivery, by measuring a concentration of the process gas and controlling the amount of gas mixture delivered in a pulse of gas flow based on the received concentration of the process gas. The control of mole delivery amount for each pulse can be achieved by adjusting flow setpoint, pulse duration, or both.

Abstract: A fluid control system and associated method for pulse delivery of a fluid includes a shutoff valve and a mass flow controller (MFC) upstream of the shutoff valve. The MFC includes a flow channel, a control valve to control flow of fluid in the flow channel, a flow sensor to measure flow rate in the flow channel, and a controller having a valve input from the shutoff valve indicating opening of the shutoff valve. The controller is configured to respond to the valve input to control flow of fluid through the control valve to initiate and terminate a pulse of fluid from the flow channel to the shutoff valve to control a mass of fluid delivered during the pulse of fluid. The valve input can be a pressure signal, and the MFC can include a pressure sensor to sense the pressure signal.

Abstract: In a pulse gas delivery system, a chamber is pre-charged to a prescribed pressure through an upstream valve. Thereafter, a downstream control valve is opened to control flow of the gas during a gas pulse. A dedicated controller may control the downstream control valve in a feedback loop during the pulse based on pressure and temperature detected during the pulse.

Abstract: Pulsed gas delivery is obtained with mass flow control using a thermal mass flow sensor and control valve. The controller is augmented for pressure control with a downstream pressure sensor. In separate control modes of operation, the control valve is controlled in response to the flow sensor during pulse gas delivery mode and controlled in response to the downstream pressure sensor during pressure control mode of operation.

Abstract: A gas delivery system and associated method includes a flow channel, a control valve, a downstream pressure sensor, and a controller. The control valve controls flow of gas in the flow channel. The downstream pressure sensor, located downstream of the control valve, measures gas pressure in the flow channel. The controller has an external trigger input to receive a trigger signal applied to a shutoff valve downstream from the control valve. The controller operates in separate modes based on a state of the trigger signal. In a non-triggered mode, the controller controls pressure at the pressure sensor via the control valve in accordance with a first gain schedule. In the triggered mode, the controller controls the pressure at the pressure sensor via the control valve in accordance with a second gain schedule that is distinct from the first gain schedule.

Abstract: A system and method for dividing a single mass flow into secondary flows of a desired ratio. The system and method include paths for the secondary flows that include a laminar flow element and two pressure sensors. The nonlinear relationship between flow and pressure upstream and downstream of the laminar flow elements can be transformed into a function comprised of the upstream and downstream pressure that has a linear relationship with the flow. This transformation allows for flow ratio control applications using signals from pressure sensors even if there is no information the fluid species and the flow rate into the flow ratio controller.

Abstract: A system and method for dividing a single mass flow into secondary flows of a desired ratio. The system and method include paths for the secondary flows that include a laminar flow element and two pressure sensors. The nonlinear relationship between flow and pressure upstream and downstream of the laminar flow elements can be transformed into a function comprised of the upstream and downstream pressure that has a linear relationship with the flow. This transformation allows for flow ratio control applications using signals from pressure sensors even if there is no information the fluid species and the flow rate into the flow ratio controller.

Abstract: A system and method provides a more precise mole delivery amount of a process gas, for each pulse of a pulse gas delivery, by measuring a concentration of the process gas and controlling the amount of gas mixture delivered in a pulse of gas flow based on the received concentration of the process gas. The control of mole delivery amount for each pulse can be achieved by adjusting flow setpoint, pulse duration, or both.

Abstract: A system for delivering pulses of a desired mass of gas to a tool, comprising: a mass flow controller including flow sensor, a control valve and a dedicated controller configured and arranged to receive a recipe of a sequence of steps for opening and closing the control valve so as to deliver as sequence of gas pulses as a function of the recipe. The mass flow controller is configured and arranged so as to operate in either one of at least two modes: as a traditional mass flow controller (MFC) mode or in a pulse gas delivery (PGD) mode.

Abstract: A mass flow control system can be self verified for its accuracy when controlling a flow to a process. The system comprises: a control valve for controlling the flow of fluid through the system as a function of a control signal; a controller for generating the control signal as a function of measured flow of fluid through the system and a targeted flow set point; a pressure sensor for measuring the controlling fluid pressure for use in measuring and verifying the flow rate; and a source of fluid for providing a known volume of fluid for use in verifying the system accuracy anytime between steps of the flow control process.

Abstract: In a pulse gas delivery system, a chamber is pre-charged to a prescribed pressure through an upstream valve. Thereafter, a downstream control valve is opened to control flow of the gas during a gas pulse. A dedicated controller may control the downstream control valve in a feedback loop during the pulse based on pressure and temperature detected during the pulse.

Abstract: A fluid control system and associated method for pulse delivery of a fluid includes a shutoff valve and a mass flow controller (MFC) upstream of the shutoff valve. The MFC includes a flow channel, a control valve to control flow of fluid in the flow channel, a flow sensor to measure flow rate in the flow channel, and a controller having a valve input from the shutoff valve indicating opening of the shutoff valve. The controller is configured to respond to the valve input to control flow of fluid through the control valve to initiate and terminate a pulse of fluid from the flow channel to the shutoff valve to control a mass of fluid delivered during the pulse of fluid. The valve input can be a pressure signal, and the MFC can include a pressure sensor to sense the pressure signal.

Abstract: A fluid control system and associated method for pulse delivery of a fluid includes a shutoff valve and a mass flow controller (MFC) upstream of the shutoff valve. The MFC includes a flow channel, a control valve to control flow of fluid in the flow channel, a flow sensor to measure flow rate in the flow channel, and a controller having a valve input from the shutoff valve indicating opening of the shutoff valve. The controller is configured to respond to the valve input to control flow of fluid through the control valve to initiate and terminate a pulse of fluid from the flow channel to the shutoff valve to control a mass of fluid delivered during the pulse of fluid. The valve input can be a pressure signal, and the MFC can include a pressure sensor to sense the pressure signal.