Tiled substrates for deposition and epitaxial lift off processes
View Patent ↗Embodiments of the invention generally relate to epitaxial lift off (ELO) films and methods for producing such films. Embodiments provide a method to simultaneously and separately grow a plurality of ELO films or stacks on a common support substrate which is tiled with numerous epitaxial growth substrates or surfaces. Thereafter, the ELO films are removed from the epitaxial growth substrates by an etching step during an ELO process. The tiled growth substrate contains the epitaxial growth substrates disposed on the support substrate may be reused to grow further ELO films. In one embodiment, a tiled growth substrate is provided which includes two or more gallium arsenide growth substrates separately disposed on a support substrate having a coefficient of thermal expansion within a range from about 5×10 −6 ° C. −1 to about 9×10 −6 ° C. −1 .
1. A gallium arsenide substrate assembly, comprising:
a support substrate comprising a coefficient of thermal expansion within a range from about 5×10 −6 ° C. −1 to about 9×10 −6 ° C. −1 ;
an adhesion layer disposed on the support substrate; and
at least two gallium arsenide growth substrates separately disposed on the adhesion layer and next to each other, wherein a gap extends between and separates the gallium arsenide growth substrates from each other.
2. The gallium arsenide substrate assembly of claim 1 , wherein the coefficient of thermal expansion is within a range from about 5.2×10 −6 ° C. −1 to about 8.5×10 −6 ° C. −1 .
3. The gallium arsenide substrate assembly of claim 1 , wherein the at least two gallium arsenide growth substrates comprise 4 or more gallium arsenide growth substrates.
4. The gallium arsenide substrate assembly of claim 3 , wherein the at least two gallium arsenide growth substrates comprise 12 or more gallium arsenide growth substrates.
5. The gallium arsenide substrate assembly of claim 1 , wherein the support substrate comprises a material selected from the group consisting of niobium, niobium alloys, titanium carbide, magnesium silicate, steatite, tungsten carbide, tungsten carbide cermet, iridium, alumina, alumina ceramics, zirconium, zirconium alloys, zirconia, zirconium carbide, osmium, tantalum, hafnium, molybdenum, molybdenum alloys, oxides thereof, silicates thereof, alloys thereof, derivatives thereof, and combinations thereof.
6. The gallium arsenide substrate assembly of claim 1 , wherein the support substrate has no porosity or substantially no porosity.
7. The gallium arsenide substrate assembly of claim 1 , wherein the support substrate is resistant or substantially resistant to hydrogen fluoride or hydrofluoric acid.
8. The gallium arsenide substrate assembly of claim 1 , wherein the adhesion layer comprises an optical adhesive or a UV-curable adhesive.
9. The gallium arsenide substrate assembly of claim 8 , wherein the adhesion layer comprises a mercapto ester compound.
10. The gallium arsenide substrate assembly of claim 9 , wherein the adhesion layer further comprises a material selected from the group consisting of butyl octyl phthalate, tetrahydrofurfuryl methacrylate, acrylate monomer, derivatives thereof, and combinations thereof.
11. The gallium arsenide substrate assembly of claim 1 , wherein the adhesion layer comprises silicone or sodium silicate.
12. A gallium arsenide substrate assembly, comprising:
an adhesion layer disposed on a support substrate; and
at least two gallium arsenide growth substrates separately disposed on the adhesion layer and next to each other, wherein the support substrate comprises a coefficient of thermal expansion for providing a maximum strain of about 0.1% or less within the gallium arsenide growth substrates at a temperature of about 650° C. or less, and a gap extends between and separates the gallium arsenide growth substrates from each other.
13. The gallium arsenide substrate assembly claims 12 , wherein the coefficient of thermal expansion is about 9×10 −6 ° C. −1 or less.
14. The gallium arsenide substrate assembly of claim 13 , wherein the coefficient of thermal expansion is within a range from about 5×10 −6 ° C −1 to about 8×10 −6 ° C. −1 .
15. The gallium arsenide substrate assembly of claim 12 , wherein the coefficient of thermal expansion is within a range from about 5.2×10 −6 ° C. −1 to about 8.5×10 −6 ° C. −1 .
16. The gallium arsenide substrate assembly of claim 12 , wherein the at least two gallium arsenide growth substrates comprise 4 or more gallium arsenide growth substrates.
17. The gallium arsenide substrate assembly of claim 16 , wherein the at least two gallium arsenide growth substrates comprise 12 or more gallium arsenide growth substrates.
18. The gallium arsenide substrate assembly of claim 12 , wherein the support substrate comprises a material selected from the group consisting of niobium, niobium alloys, titanium carbide, magnesium silicate, steatite, tungsten carbide, tungsten carbide cermet, iridium, alumina, alumina ceramics, zirconium, zirconium alloys, zirconia, zirconium carbide, osmium, tantalum, hafnium, molybdenum, molybdenum alloys, oxides thereof, silicates thereof, alloys thereof, derivatives thereof, and combinations thereof.
19. The gallium arsenide substrate assembly of claim 12 , wherein the support substrate has no porosity or substantially no porosity.
20. The gallium arsenide substrate assembly of claim 12 , wherein the support substrate is resistant or substantially resistant to hydrogen fluoride or hydrofluoric acid.
21. The gallium arsenide substrate assembly of claim 12 , wherein the adhesion layer comprises an optical adhesive or a UV-curable adhesive.
22. The gallium arsenide substrate assembly of claim 21 , wherein the adhesion layer comprises a mercapto ester compound.
23. The gallium arsenide substrate assembly of claim 22 , wherein the adhesion layer further comprises a material selected from the group consisting of butyl octyl phthalate, tetrahydrofurfuryl methacrylate, acrylate monomer, derivatives thereof, and combinations thereof.
24. The gallium arsenide substrate assembly of claim 12 , wherein the adhesion layer comprises silicone or sodium silicate.