Deposition of titanium amides
View Patent ↗The present invention is a process for enhancing the chemical vapor deposition of titanium nitride from a titanium containing precursor selected from the group consisting of tetrakis(dimethylamino)titanium, tetrakis(diethylamino)titanium and mixtures thereof, reacted with ammonia to produce the titanium nitride on a semiconductor substrate by the addition of organic amines, such as dipropylamine, in a range of approximately 10 parts per million by weight to 10% by weight, preferably 50 parts per million by weight to 1.0 percent by weight, most preferably 100 parts per million by weight to 5000 parts per million by weight to the titanium containing precursor wherein prior to the reaction, said titanium containing precursor is subjected to a purification process to remove hydrocarbon impurities from the titanium containing precursor. It is shown that addition of small amounts of organic amines enhance the deposition rate of titanium nitride, while the presence of hydrocarbons, such as n-decane, retard the deposition rate of titanium nitride.
1. A process for determining a predicted deposition rate of a batch of a titanium containing precursor in a chemical vapor deposition of a titanium containing compound on a substrate, comprising; analyzing the organic amine content of said batch to determine an analytical amine content, comparing said analytical amine content against an amine content standard and determining said predicted deposition rate from a deposition rate standard based upon the deviation of the analytical amine content from said amine content standard wherein said predicted deposition rate is greater than the deposition rate standard when said analytical amine content is greater than said amine content standard and said predicted deposition rate is less than said deposition rate standard when said analytical amine content is less than said amine content standard.
2. The process of claim 1 wherein said analyzing the organic amine content of said batch is an analysis selected from the group consisting of solid-phase microextraction and short path distillation on a wiped film still.
3. The process of claim 1 wherein said titanium containing precursor is selected from the group consisting of tetrakis(dimethylamino)titanium, tetrakis(diethylamino)titanium and mixtures thereof.
4. The process of claim 1 wherein said batch of a titanium containing precursor is analyzed for the hydrocarbon content of said batch to determine an analytical hydrocarbon content, comparing said analytical hydrocarbon content against an hydrocarbon content standard, determining a second predicted deposition rate from a hydrocarbon deposition rate standard based upon the deviation of the analytical hydrocarbon content from said hydrocarbon content standard and correlating said second predicted deposition rate with said predicted deposition rate to determine a third combined amine/hydrocarbon predicted deposition rate for said batch.
5. The process of claim 4 wherein said titanium containing compound is titanium nitride.
6. A process for determining a predicted deposition rate of a batch of a titanium containing precursor in a chemical vapor deposition of a titanium containing compound on a substrate, comprising; analyzing the hydrocarbon content of said batch to determine an analytical hydrocarbon content, comparing said analytical hydrocarbon content against an hydrocarbon content standard and determining said predicted deposition rate from a deposition rate standard based upon the deviation of the analytical hydrocarbon content from said hydrocarbon content standard.
7. The process of claim 6 wherein said predicted deposition rate is less than the deposition rate standard when said analytical hydrocarbon content is greater than said hydrocarbon content standard and said predicted deposition rate is greater than said deposition rate standard when said analytical hydrocarbon content is less than said hydrocarbon content standard.
8. The process of claim 6 wherein said analyzing the hydrocarbon content of said batch is an analysis selected from the group consisting of solid-phase microextraction and short path distillation on a wiped film still.
9. The process of claim 6 wherein said titanium containing precursor is selected from the group consisting of tetrakis(dimethylamino)titanium, tetrakis(diethylamino)titanium and mixtures thereof.