High Purity Ethylenediamine for Semiconductor Applications

Abstract

Ethylenediamine (EDA) compositions and methods for making the EDA that is suitable for use in thin-film semiconductor processing applications, are disclosed. The EDA is purified to remove water and trace metals. Water levels below about 50 ppm by weight are achieved by passing liquid through 3A type molecular sieve in a packed bed. Metallic impurities are removed by distillation and the resulting product is packaged in specially dried and optionally pre-conditioned containers.

1 . Ethylenediamine wherein the ethylenediamine is greater than about 99.9 weight percent pure and contains less about 50 ppm water and less than about 100 ppb trace metals. 
     
     
         2 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 50 ppb of aluminum, chromium, copper, iron, magnesium, manganese, molybdenum, nickel, titanium and zinc. 
     
     
         3 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 10 ppm of water. 
     
     
         4 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 5 ppm of water. 
     
     
         5 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 1 ppm of water. 
     
     
         6 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 5 ppm of halides. 
     
     
         7 . The ethylenediamine of  claim 6  wherein the halide is chlorine. 
     
     
         8 . The ethylenediamine of  claim 1  wherein the ethylenediamine contains less than about 5 ppb of alkali metals. 
     
     
         9 . The ethylenediamine of  claim 8  wherein the alkali metal is sodium. 
     
     
         10 . A composition comprising the ethylenediamine of  claim 1 . 
     
     
         11 . A method for treating ethylenediamine comprising contacting ethylenediamine with a molecular sieve comprising type 3A zeolite under conditions sufficient to reduce the amount of water in the ethylenediamine to less than about 50 ppm; and, distilling the ethylenediamine under conditions sufficient to reduce the amount of trace metals to less than about 100 ppb. 
     
     
         12 . The method of  claim 11  wherein the ethylenediamine is greater than about 99.9 weight percent pure. 
     
     
         13 . The method of  claim 11  wherein the ethylenediamine flows through a bed of type 3A zeolite 
     
     
         14 . A method for treating a container comprising introducing an inert gas into the container while heating the container to a temperature of greater than about 120° C., introducing the ethylenediamine of  claim 9  into the container; and removing the ethylenediamine. 
     
     
         15 . The method of  claim 14  wherein the container comprises stainless steel. 
     
     
         16 . A container containing the ethylenediamine of  claim 2 . 
     
     
         17 . The container of  claim 16  comprising an inert headspace gas selected from helium, nitrogen, argon, and mixtures thereof.