Liquid dispensing system

Abstract

A control system employed for dispensing liquid to a process via a flow passage from a container including an outer container and an inner container. The inner container is made of a flexible material and occupied by the liquid so that pressurized fluid in a compression space between the outer container and the inner container forces liquid out of the inner container to the manufacturing process via the flow passage. A pressure sensor is positioned to sense pressure in the flow passage. A controller that is responsive to the pressure sensor controls flow of the liquid in the flow passage by controlling the pressure of the pressurized fluid in the compression space.

1 . In a system for dispensing liquid to a process from a container via a flow passage, the container including an outer container and an inner container, the inner container made of a flexible material and occupied by the liquid so that pressurized fluid in a compression space between the outer container and the inner container forces liquid out of the inner container to the manufacturing process via the flow passage, a control system comprising: 
 a pressure sensor positioned to sense pressure in the flow passage; and    a controller, responsive to the pressure sensor, adapted to control flow of the liquid in the flow passage by controlling the pressure of the pressurized fluid in the compression space.    
   
   
       2 . The control system of  claim 1 , wherein the controller is programmable with a dispense recipe comprising recipe components selected from the group consisting of: a recipe amount of liquid to be dispensed to the process, a dispense duration within which the recipe amount of liquid is to be dispensed to the process, liquid properties, process environment properties, and combinations thereof.  
   
   
       3 . The control system of  claim 2 , wherein the controller controls flow of the liquid in the flow passage based on the dispense recipe.  
   
   
       4 . The control system of  claim 1 , and further comprising: 
 a fluid controller responsive to a signal from the controller to adjust a pressure in the compression space.    
   
   
       5 . The control system of  claim 4 , wherein the fluid controller comprises a block valve.  
   
   
       6 . The control system of  claim 5 , wherein the block valve comprises a solenoid valve.  
   
   
       7 . The control system of  claim 6 , wherein the controller controls the pressure of the pressurized fluid in the compression space by providing a pulse width modulated drive signal to the solenoid valve.  
   
   
       8 . The control system of  claim 7 , wherein the controller includes a proportional feedback component to determine an error signal used for modulating the drive signal to the solenoid valve, the error signal based on the pressure in the flow passage sensed by the pressure sensor.  
   
   
       9 . The control system of  claim 7 , wherein the controller includes a proportional-integral-derivative (PID) feedback component to determine an error signal used for modulating the drive signal to the solenoid valve, the error signal based on the pressure in the flow passage sensed by the pressure sensor.  
   
   
       10 . The control system of  claim 1 , and further comprising: 
 a pressure release valve connected between a pressure release drain and the compression space to facilitate release of pressure in the compression space.    
   
   
       11 . The control system of  claim 10 , wherein the pressure release valve comprises a block valve.  
   
   
       12 . The control system of  claim 11 , wherein the block valve comprises a solenoid valve.  
   
   
       13 . The control system of  claim 1 , and further comprising: 
 a stop valve for terminating dispensing of the liquid to the process when a recipe amount of liquid has been dispensed to the process.    
   
   
       14 . A method for dispensing liquid to a process from a container via a flow passage, wherein the container includes an outer container and a flexible inner container, the flexible inner container containing the liquid, the method comprising: 
 sensing pressure of the liquid from the inner container in the flow passage between the inner container and the process; and    controlling pressure of pressurized fluid in a compression space between the inner container and the outer container as a function of the pressure of the liquid sensed in the flow passage to force liquid from the inner container to the process.    
   
   
       15 . The method of  claim 14 , wherein the controlling step further comprises controlling pressure of the pressurized fluid as a function of information related to the process.  
   
   
       16 . The method of  claim 14 , wherein controlling pressure of the pressurized fluid comprises: 
 adjusting at least one fluid control valve connected between a pressurized fluid source and the compression space.    
   
   
       17 . The method of  claim 16 , wherein adjusting at least one fluid control valve comprises providing a pulse width modulated drive signal to the at least one fluid control valve.  
   
   
       18 . The method of  claim 14 , and further comprising: 
 terminating dispensing of the liquid to the process when a recipe amount of liquid has been dispensed to the manufacturing process.    
   
   
       19 . A liquid handling system comprising: 
 a container for dispensing liquid from an inner container to a process in response to fluid pressure applied to an outer wall of the inner container; and    a controller for providing a control signal to control the fluid pressure applied to the inner container as a function of pressure of the liquid sensed downstream of the inner container.    
   
   
       20 . The liquid handling system of  claim 19 , and further comprising: 
 a connector attachable to the container.    
   
   
       21 . The liquid handling system of  claim 20 , wherein the connector comprises a probe insertable into the inner container and defining a portion of a flow passage from the container to a process tool.  
   
   
       22 . The liquid handling system of  claim 21 , and further comprising: 
 a pressure sensor for sensing pressure of the liquid at a location in the flow passage downstream of the inner container.    
   
   
       23 . The liquid handling system of  claim 19 , wherein the controller further provides the control signal to control the fluid pressure applied to the inner container as a function of a dispense recipe.  
   
   
       24 . The liquid handling system of  claim 23 , wherein the dispense recipe comprises recipe components selected from the group consisting of: a recipe amount of liquid to be dispensed to the process, a dispense duration within which the recipe amount of liquid is to be dispensed to the process, liquid properties, process environment properties, and combinations thereof.  
   
   
       25 . The liquid handling system of  claim 19 , and further comprising: 
 a stop valve for terminating dispensing of the liquid from the inner container to the process.    
   
   
       26 . The liquid handling system of  claim 19 , and further comprising: 
 a suckback valve for drawing liquid back into the inner container after terminating dispensing of the liquid.