Thin-film devices formed from solid particles
Methods and devices are provided for forming thin-films from solid group IIIA-based particles. In one embodiment of the present invention, a method is described comprising of providing a first material comprising an alloy of a) a group IIIA-based material and b) at least one other material. The material may be included in an amount sufficient so that no liquid phase of the alloy is present within the first material in a temperature range between room temperature and a deposition or pre-deposition temperature higher than room temperature, wherein the group IIIA-based material is otherwise liquid in that temperature range. The other material may be a group IA material. A precursor material may be formulated comprising a) particles of the first material and b) particles containing at least one element from the group consisting of: group IB, IIIA, VIA element, alloys containing any of the foregoing elements, or combinations thereof. The temperature range described above may be between about 20° C. and about 200° C. It should be understood that the alloy may have a higher melting temperature than a melting temperature of the IIIA-based material in elemental form.
1. A method comprising:
providing a first material comprising of at least a solid binary compound of a) a group IIIA-based material and b) a second material comprised of at least one group IA-based material, wherein the second material is included in an amount sufficient so that no liquid phase of the compound is present within the first material in a temperature range between room temperature and a deposition or pre-deposition temperature higher than room temperature, wherein the group IIIA-based material is otherwise liquid in that temperature range,
formulating a precursor material comprising a) particles of the first material and b) particles containing at least one element from the group consisting of: group IB, IIIA, VIA element, alloys containing any of the foregoing elements, or combinations thereof.
2. The method of claim 1 wherein the temperature range is between about 20° C. and about 200° C.
3. The method of claim 1 wherein the compound has a higher melting temperature than a melting temperature of the IIIA-based material in elemental form.
4. The method of claim 1 wherein the second material comprises Na.
5. The method of claim 1 wherein the second material comprises NaF.
6. The method of claim 1 , wherein the second material contains an element chosen from the group consisting of sodium (Na), potassium (K), lithium (Li), Rubidium (Rb), Cesium (Cs), an alloy containing any of the foregoing, or combinations thereof.
7. The method of claim 1 wherein the group IIIA-based material of the first material is In.
8. The method of claim 1 wherein the group IIIA-based material of the first material is Ga.
9. The method of claim 1 wherein the solid compound comprises a binary alloy.
10. The method of claim 1 wherein the solid compound comprises a multinary alloy.
11. The method of claim 1 wherein the solid compound comprises a Ga-Na based alloy.
12. The method of claim 1 wherein the solid compound contains Ga 4 Na.
13. The method of claim 1 wherein the solid compound contains Ga 39 Na 22 .
14. The method of claim 1 wherein the solid compound contains at least about 0.6 weight percent Na.
15. The method of claim 1 wherein the solid compound contains at least about 8 weight percent Na.
16. The method of claim 1 further comprising:
formulating an ink including the precursor material;
solution depositing the ink onto a substrate to form a precursor layer on the substrate; and
reacting the precursor layer in a suitable atmosphere to form a group IB-IIIA based film.
17. The method of claim 16 wherein the film has a Cu/(In+Ga) compositional range of about 0.01 to about 1.0 and a Ga/(In+Ga) compositional range of about 0.01 to about 1.0.
18. The method of claim 16 wherein the film has a Cu/(In+Ga) compositional range of about >1.0 for Cu/(In+Ga) and a Ga/(In+Ga) compositional range of about 0.01 to about 1.0.
19. The method of claim 16 wherein the film has a Cu/(In+Ga) compositional range of about 0.01 to about 1.0 and a Ga/(In+Ga) compositional range of about 0.01 to about 1.0.
20. The method of claim 16 wherein the film has a desired Cu/(In+Ga) molar ratio is in the range of about 0.7 to about 1.0 and a desired Ga/(Ga+In) molar ratio in the range of about 0.1 to about 0.8.