Mass flow controller for substrate processing

A method for controlling a mass flow controller (MFC), comprising:

• receiving, from a Coriolis sensor of the MFC, a density signal and a mass flow rate signal for a mixture of a process fluid and a carrier fluid, the MFC being connected to both a first flow line of the process fluid and a second flow line of the carrier gas;
• calculating a fluid mix ratio of the mixture based on the density signal;
• adjusting a flow rate of the process fluid entering the MFC based on the fluid mix ratio;
• calculating a mass flow rate of the mixture based on the mass flow rate signal;
• and
• adjusting an output flow rate of the mixture exiting the MFC based on the mass flow rate of the mixture.

A mass flow controller, comprising:

• a mixing and sensing module for mixing a process fluid and a carrier fluid into a mixture, the mixing and sensing module provides a density signal and a mass flow rate signal for the mixture, the mixing and sensing module being connected to both a first flow line of the process fluid and a second flow line of the carrier gas;
• an inlet valve for controlling a flow rate of process fluid entering the mixing and sensing module;
• an outlet valve for controlling an output flow rate of the mixture exiting the mixing and sensing module;
• and
• a controller for calculating a fluid mix ratio of process fluid to carrier fluid based on the density signal and for calculating a mass flow rate of the mixture based on the mass flow rate signal for the mixture, wherein the controller is configured for adjusting the inlet valve based on the fluid mix ratio and for adjusting the outlet valve based on the mass flow rate of the mixture.