초록 ▼

A fluid mass flow controller, particularly adapted for controlling mass flow rates of toxic and reactive gases used in semiconductor device fabrication, includes a control circuit connected to pressure sensors for sensing the differential pressure across a flow restrictor in the mass flow controller

A fluid mass flow controller, particularly adapted for controlling mass flow rates of toxic and reactive gases used in semiconductor device fabrication, includes a control circuit connected to pressure sensors for sensing the differential pressure across a flow restrictor in the mass flow controller for controlling a valve to control the fluid mass flow rate to a setpoint. The control circuit compares the differential pressure with the downstream pressure at a measured temperature with a data set of a gas passing through the flow controller for a range of differential pressures and downstream pressures and adjusts the flow control rate accordingly. The flow controller is mechanically uncomplicated including a two part body for supporting the pressure sensors, a remotely controllable flow control valve and the flow restrictor. The flow restrictor may comprise an orifice or nozzle but preferably comprises a sintered metal plug having a predetermined porosity for the expected materials and flow conditions to which the flow controller will be exposed. Process gases to be controlled by the flow controller are tested to provide data sets of mass flow rates at selected temperatures for a range of differential pressures across a flow restrictor and a range of downstream pressures.

대표청구항 ▼

A fluid mass flow controller, particularly adapted for controlling mass flow rates of toxic and reactive gases used in semiconductor device fabrication, includes a control circuit connected to pressure sensors for sensing the differential pressure across a flow restrictor in the mass flow controller

A fluid mass flow controller, particularly adapted for controlling mass flow rates of toxic and reactive gases used in semiconductor device fabrication, includes a control circuit connected to pressure sensors for sensing the differential pressure across a flow restrictor in the mass flow controller for controlling a valve to control the fluid mass flow rate to a setpoint. The control circuit compares the differential pressure with the downstream pressure at a measured temperature with a data set of a gas passing through the flow controller for a range of differential pressures and downstream pressures and adjusts the flow control rate accordingly. The flow controller is mechanically uncomplicated including a two part body for supporting the pressure sensors, a remotely controllable flow control valve and the flow restrictor. The flow restrictor may comprise an orifice or nozzle but preferably comprises a sintered metal plug having a predetermined porosity for the expected materials and flow conditions to which the flow controller will be exposed. Process gases to be controlled by the flow controller are tested to provide data sets of mass flow rates at selected temperatures for a range of differential pressures across a flow restrictor and a range of downstream pressures. cuted in a client-server distributed data processing system. 57. The computer program product of claim 40, wherein the setting is an optimal setting. 58. A method of controlling the operation of a plurality of implantable devices implanted in a human user, comprising: obtaining configuration information from the plurality of implantable devices; and determining a setting for a selected implantable device of the plurality of implantable devices taking into consideration possible interactions of the operation of the selected implantable device on the operation of the other implantable devices of the plurality of implantable devices.