Abstract:
A pressure for a chamber is regulated by controlling either the exhaust pressure at the exhaust side of a first vacuum pump or the internal pressure at a compression stage of the first vacuum pump, where the first vacuum pump is directly communicating with the chamber. The pressure of the chamber can be regulated by combinations of the following: controlling the variable rotational frequency of a roots vacuum pump, a pre-vacuum pump, or a high compression pump; controlling a control valve between a pre-vacuum pump and the first vacuum pump; controlling a control valve for injecting gas into the exhaust side of the first vacuum pump or into the compression stage of the first vacuum pump; and controlling a control valve or control valves for bypassing the first vacuum pump or a compression stage or compression stages of the first vacuum pump. To regulate the pressure in the chamber, several types of control rules can be used, including: a PID control rule, a gain scheduler, and a threshold comparison control rule.
Abstract:
The present invention provides methods and apparatus for controlling gas flow to a semiconductor-processing chamber. The invention includes deactivating ratio setpoint feedback control in a flow ratio controller; initiating gas flow through the flow ratio controller; moving valves of the flow ratio controller to a preset position based on a stored position when an upstream pressure reaches a stored upstream pressure value, wherein the stored position and the stored upstream pressure value were stored during a prior process run; determining that steady state flow ratio controller output flows have been reached; and activating ratio setpoint feedback control in the flow ratio controller. Numerous additional features are disclosed.
Abstract:
Methods and apparatus are disclosed herein. In some embodiments, methods of controlling process chambers may include predetermining a relationship between pressure in a processing volume and a position of an exhaust valve as a function of a process parameter; setting the process chamber to a first state having a first pressure in the processing volume and a first value of the process parameter, wherein the exhaust valve is set to a first position based on the predetermined relationship to produce the first pressure at the first value; determining a pressure control profile to control the pressure as the process chamber is changed to a second state having a second pressure and a second process parameter value from the first state; and applying the pressure control profile to control the pressure by varying the position of the exhaust valve while changing the process chamber to the second state.
Abstract:
A method and apparatus that solve the problem of accurate measurement of gas flow so that the delivery of gases in semiconductor processing may be performed with greater confidence and accuracy by performing real-time characterization of a lead-line for mass flow controller (MFC) flow verification are provided. In one embodiment a mass flow verifier (MFV) provides rate of rise information to a controller via a digital interface without correcting for lead-line influences. After receiving the rate of rise data, the tool host computer computes a gas mass correction factor in real-time based on at least one of the following: MFC temperature sensor data, lead-line temperature sensor data, lead-line pressure transducer data, and lead-line volume. The rate of rise data and gas mass correction factor are used to compute accurate mass flow. The accurate mass flow information may be used to calibrate the MFC.
Abstract:
A method and apparatus are provided for a cost effective pressure dampening device used in a fluid delivery system for substrate processing. In one embodiment, the pressure dampening device is disposed between a mounting substrate and a control valve within a fluid control assembly in fluid communication with a substrate processing chamber. The pressure dampening device is capable of dampening small pressure perturbations in a process fluid which is used for substrate processing.
Abstract:
A method and apparatus are provided for a cost effective pressure dampening device used in a fluid delivery system for substrate processing. In one embodiment, the pressure dampening device is disposed between a mounting substrate and a control valve within a fluid control assembly in fluid communication with a substrate processing chamber. The pressure dampening device is capable of dampening small pressure perturbations in a process fluid which is used for substrate processing.