Monoalkyl tin trialkoxides and/or monoalkyl tin triamides with low metal contamination and/or particulate contamination, and corresponding methods
The purification of monoalkyl tin trialkoxides and monoalkyl tin triamides are described using fractional distillation and/or ultrafiltration. The purified compositions are useful as radiation sensitive patterning compositions or precursors thereof. The fractional distillation process has been found to be effective for the removal of metal impurities down to very low levels. The ultrafiltration processes have been found to be effective at removal of fine particulates. Commercially practical processing techniques are described.
1. A container of a composition comprising a container formed of plastic or dealkalized material and within the container a mixture of a semiconductor grade solvent and a solvated monoalkyl tin triamide (RSn(NR′ 2 ) 3 ), wherein the mixture has a tin concentration from about 0.01M to about 1.4M and a concentration of non-tin metals or metalloid elements of each no more than 5 parts-per-billion (ppb) by mass.
2. The container of claim 1 wherein the semiconductor grade solvent comprises an alcohol or mixture of alcohols.
3. The container of claim 1 wherein the R is a branched alkyl ligand represented by R 1 R 2 R 3 C—, where R 1 and R 2 are independently an alkyl group with 1-10 carbon atoms, and R 3 is hydrogen or an alkyl group with 1-10 carbon atoms.
4. The container of claim 1 wherein the R comprises methyl (CH 3 —), ethyl (CH 3 CH 2 —), isopropyl (CH 3 CH 3 HC—), t-butyl ((CH 3 ) 3 C—), t-amyl (CH 3 CH 2 (CH 3 ) 2 C—), sec-butyl (CH 3 (CH 3 CH 2 )CH—), neopentyl (CH 3 ) 3 CCH 2 —), cyclohexyl, cyclopentyl, cyclobutyl, or cyclopropyl.
5. The container of claim 1 further comprising a monoalkyl tin triaamide (R 1 Sn(NR″ 2 ) 3 ) wherein the R is different from R 1 and the R′ is the same or different from R″.
6. The container of claim 1 wherein R′ comprises a methyl group, ethyl group, isopropyl group, or t-butyl group.
7. The container of claim 1 comprising no more than about 1 mole % dialkyltin compounds.
8. The container of claim 1 , wherein the concentration of non-tin metals or metalloid elements of each no more than 2.5 parts-per-billion (ppb) by mass.
9. The container of claim 8 having a tin concentration from about 0.0125M to about 0.25M and the concentration of non-tin metals or metalloid elements of each no more than 2.5 parts-per-billion (ppb) by mass, wherein the solvent comprises an alcohol or mixture of alcohols.
10. The container of claim 1 , wherein the mixture has a particle contamination of no more than about 40 particles per mL with a particle size of at least about 70 nm as determined by light scattering.