Methods of growing CdTe-based materials at high rates
View Patent ↗Systems and methods for growing high-quality CdTe-based materials at high growth rates are provided. According to an aspect of the invention, a method includes depositing a first CdTe-based layer on a CdTe-based template at a rate of greater than 1 μm/min. Each of the first CdTe-based layer and the CdTe-based template has a single-crystal structure and/or a large-grain polycrystalline structure. The depositing is performed by physical vapor deposition.
1. A method comprising:
depositing a first CdTe-based layer on a CdTe-based template at a rate of between 1 μm/min to 8 μm/min, wherein:
each of the first CdTe-based layer and the CdTe-based template has at least one of a single-crystal structure or a large-grain polycrystalline structure, and
the depositing is performed by physical vapor deposition while maintaining a temperature of a substrate on which the first CdTe-based layer is deposited between 400° C. and 650° C. during the depositing.
2. The method according to claim 1 , wherein the physical vapor deposition comprises close-spaced sublimation (CSS) or vapor transport deposition (VTD).
3. The method according to claim 1 , wherein the first CdTe-based layer comprises CdTe or CdZnTe.
4. The method according to claim 1 , wherein the CdTe-based template comprises CdTe, CdZnTe, CdMgTe, CdMnTe, HgCdTe, or an alloy thereof.
5. The method according to claim 1 , further comprising maintaining a temperature of a source of the first CdTe-based layer between 500° C. and 700° C. during the depositing.
6. The method according to claim 1 , wherein the CdTe-based template is deposited by molecular beam epitaxy (MBE), Bridgman growth, or a traveling heater method (THM).
7. The method according to claim 6 , wherein the CdTe-based template is deposited on a ZnTe layer, which is deposited on a Si substrate.
8. The method according to claim 1 , wherein the CdTe-based template has a thickness between 10 nm and 1 mm.
9. The method according to claim 1 , wherein an average grain size of the first CdTe-based layer is greater than twice a thickness of the first CdTe-based layer.
10. The method according to claim 1 , further comprising doping the first CdTe-based layer.
11. The method according to claim 10 , wherein the first CdTe-based layer is doped with As or P.
12. The method according to claim 10 , further comprising annealing the first CdTe-based layer at a temperature between 400° C. and 700° C. for a duration between 30 seconds and 30 minutes.