Low temperature deposition of phase change memory materials
View Patent ↗A system and method for forming a phase change memory material on a substrate, in which the substrate is contacted with precursors for a phase change memory chalcogenide alloy under conditions producing deposition of the chalcogenide alloy on the substrate, at temperature below 350° C., with the contacting being carried out via chemical vapor deposition or atomic layer deposition. Various tellurium, germanium and germanium-tellurium precursors are described, which are useful for forming GST phase change memory films on substrates.
1. A method of forming a germanium-containing film on a substrate, comprising use of a Ge(II) compound of the formula Ge(Cp(R 2 ) 5 ) 2 wherein Cp is cyclopentadienyl having R 2 substituents on the cyclopentadienyl ring carbon atoms, wherein the R 2 substituents are the same as or different from one another, and each R 2 is independently selected from among H, C 1 -C 8 alkyl, C 1 -C 8 fluoroalkyl, C 1 -C 8 alkylamino, C 6 -C 12 aryl, C 6 -C 12 fluoroaryl, C 3 -C 8 cycloalkyl, and C 3 -C 8 cyclo-fluoroalkyl, in chemical vapor deposition or atomic layer deposition.
2. The method of claim 1 , wherein said chemical vapor deposition or atomic layer deposition is carried out at temperature below 350° C.
3. The method of claim 1 , wherein said chemical vapor deposition or atomic layer deposition is carried out at temperature below 300° C.
4. The method of claim 1 , further comprising use of an antimony precursor.
5. The method of claim 4 , further comprising use of a tellurium precursor.
6. The method of claim 5 , wherein chemical vapor deposition or atomic layer deposition is employed to form a phase change memory material.
7. The method of claim 6 , comprising fabricating the phase change memory material into a phase change memory device.
8. The method of claim 1 , wherein the method of forming a germanium-containing film on a substrate comprises use of the Ge(II) compound in chemical vapor deposition.
9. The method of claim 8 , wherein the chemical vapor deposition comprises delivering the Ge(II) compound to the substrate in a carrier gas stream including a vapor of the Ge(II) compound.
10. The method of claim 1 , wherein the method of forming a germanium-containing film on a substrate comprises use of the Ge(II) compound in atomic layer deposition.
11. The method of claim 1 , wherein at least one R 2 is C 1 -C 8 alkyl.
12. The method of claim 1 , wherein at least one R 2 is C 1 -C 8 fluoroalkyl.
13. The method of claim 1 , wherein at least one R 2 is C 1 -C 8 alkylamino.
14. The method of claim 1 , wherein at least one R 2 is C 6 -C 12 aryl.
15. The method of claim 1 , wherein at least one R 2 is C 6 -C 12 fluoroaryl.
16. The method of claim 1 , wherein at least one R 2 is C 3 -C 8 cycloalkyl.
17. The method of claim 1 , wherein at least one R 2 is C 3 -C 8 cyclo-fluoroalkyl.
18. The method of claim 1 , wherein at least one R 2 is H.
19. The method of claim 1 , wherein the Ge(II) compound is dissolved or suspended in a compatible solvent medium.