Low vapor pressure high purity gas delivery system

Abstract

Systems, apparatuses and methods for vapor phase fluid delivery to a desired end use are provided, wherein the conditions of the system are monitored to determine when the water concentration or supply vessel surface temperature exceeds a specified value or when the low vapor pressure fluid pressure falls below a specified value for the purpose of removing a first supply vessel from service by discontinuing vapor flow from the first supply vessel and initiating vapor flow from a second supply vessel.

1 . A method for delivering vapor phase fluid under pressure from a vessel comprising the steps of:
 providing at least a first and second vessel having a fluid therein, each vessel having a vessel wall;   providing a heater in communication with each of the first and second vessel;   heating the vessel to achieve a predetermined pressure within the first and second vessel;   providing a controller in communication with the heater;   withdrawing an amount of vapor phase fluid from the first or second vessel;   providing a sensor to monitor at least one condition in the first and second vessels, said condition selected from the group consisting of: vapor phase fluid pressure; vessel wall temperature, vapor phase fluid low vapor pressure contaminant concentration, and combinations thereof, to determine the key fluid level in the first and second vessels;   monitoring the condition in the first and second vessels to determine the key fluid level in the first and second vessels;   providing a controller in communication with the sensor and a valve having an on/off position, said valve directing flow from the first or second vessel to an end use, said sensor optionally activating the valve on/off position.   
     
     
         2 . The method of  claim 1 , further comprising the step of:
 activating a first valve in communication with the first vessel to the off position, said valve diminishing the flow of vapor phase fluid from the first vessel to an end use when the condition reaches a predetermined level; and   activating a second valve in communication with the second vessel to the on position, said valve increasing the flow of vapor phase fluid from the second vessel to an end use when the condition reaches a predetermined level.   
     
     
         3 . The method of  claim 1 , wherein the vapor phase fluid is a non-air based gas selected from the group consisting of: ammonia, boron trichloride, carbon dioxide, chlorine, dichlorosilane, halocarbons, hydrogen bromide, hydrogen chloride, hydrogen fluoride, methylsilane, nitrous oxide, nitrogen trifluoride, trichlorosilane and mixtures thereof. 
     
     
         4 . The method of  claim 1 , wherein the low vapor pressure contaminant is water. 
     
     
         5 . The method of  claim 1 , wherein the first and second vessels are made from a material selected from the group consisting of: 304 stainless steel, 316 stainless steel, Hasteloy, carbon steel and mixtures thereof. 
     
     
         6 . The method of  claim 1 , wherein the first and second vessels are selected from the group consisting of: ISO container vessels, ton container vessels and drum container vessels. 
     
     
         7 . The method of  claim 1 , wherein the heater is an electrical resistance heater selected from the group consisting of: silicon blanket heaters, band heaters, heating bars, heating tape and combinations thereof. 
     
     
         8 . The method of  claim 1 , wherein the vapor phase fluid is selected from the group consisting of: high purity vapor phase fluid, ultra-high purity vapor phase fluid, and combinations thereof. 
     
     
         9 . The method of  claim 1 , further comprising the steps of:
 substantially controlling the amount of heat delivered to the first or second vessel; and   maintaining a substantially constant pressure within the first or second vessel.   
     
     
         10 . The method of  claim 2 , wherein the end use is the manufacture of a device, said device selected from the group consisting of: a semiconductor, a liquid crystal display, a light emitting diode and a solar cell. 
     
     
         11 . A device made according to the method of  claim 2 , selected from the group consisting of: a semiconductor, a liquid crystal display and a light emitting diode.