Method and apparatus for local fluorine and nitrogen trifluoride production

Abstract

The present invention relates to a process for production, shipment, and treatment of a NH 4 F(HF) x feedstock for local production of fluorine and NF 3 for semiconductor chamber cleaning without the need for storage of large quantities of dangerous feeds and intermediate products.

1 . An apparatus for the production of NF 3  and F 2  comprising:
 an HF production unit having a source for an NH 4 F(HF) x  solution connected thereto;   an F 2  production unit connected to said HF production unit;   an F 2  purification unit connected to said F 2  production unit;   an NF 3  production unit connected to said F 2  purification unit and to said HF production unit; and   an NF 3  purification unit connected to said NF 3  production unit.   
     
     
         2 . An apparatus according to  claim 18 , further comprising:
 a facility abatement unit connected to each of said HF production, said F 2  production unit; said F 2  purification unit; said NF 3  production unit; and said NF 3  purification unit.   
     
     
         3 . An apparatus according to  claim 18 , wherein said HF production unit is a reactor constructed to contain a bath of said NH 4 F(HF) x  solution and a NH 3 —HF vapor space;
 said reactor including a heater for heating said bath of said NH 4 F(HF) x  solution to produce NH 3 —HF vapor which occupies said NH 3 —HF vapor space.   
     
     
         4 . An apparatus according to claim  20 , wherein said heater is located on the wall of said reactor. 
     
     
         5 . An apparatus according to claim  20 , wherein said heater is submerged in said bath of said NH 4 F(HF) x  solution. 
     
     
         6 . An apparatus according to claim  20 , wherein said heater is a series of pipes using a gaseous or liquid heating medium. 
     
     
         7 . An apparatus according to claim  20 , wherein said heater is an electrical resistance element heater. 
     
     
         8 . An apparatus according to claim  20 , wherein said operating temperature for said bath of said NH 4 F(HF) x  solution is from 200° C. to 240° C. 
     
     
         9 . An apparatus according to claim  20 , wherein said NH 3 —HF vapor is at a pressure from 1 atmosphere to 2 atmospheres. 
     
     
         10 . An apparatus according to claim  20 , wherein said NH 3 —HF vapor is at a pressure from 1.05 atmospheres to 1.5 atmospheres. 
     
     
         11 . An apparatus according to claim  20 , wherein said NH 3 —HF vapor is at a pressure from 1.1 atmospheres to 1.25 atmospheres. 
     
     
         12 . An apparatus according to claim  20 , wherein said bath of said NH 4 F(HF) x  solution is provided to said reactor from said source of NH 4 F(HF) x  solution. 
     
     
         13 . An apparatus according to claim  20 , wherein said bath of said NH 4 F(HF) x  solution is provided from said NF 3  production unit. 
     
     
         14 . An apparatus according to claim  20 , wherein said bath of NH 4 (HF) x  solution is preheated using a heat exchanger prior to being introduced to said reactor and said heating medium used in said heat exchanger is said NH 3 —HF vapor. 
     
     
         15 . An apparatus according to claim  20 , further including a source for F 2  connected to said reactor. 
     
     
         16 . An apparatus according to claim  32 , further including a heat exchanger in said reactor for transferring the heat of reaction between NF 3  vapor and F 2  provided to said reactor, to the bath of said NH 4 F(HF) x  solution. 
     
     
         17 . An apparatus according to claim  20 , further including an HF purification column connected to a product outlet of said reactor, said HF purification column. 
     
     
         18 . An apparatus according to claim  34 , wherein said HF purification column is a rectifying distillation column having packing and a condenser.