Low temperature junction growth using hot-wire chemical vapor deposition
A system and a process for forming a semi-conductor device, and solar cells ( 10 ) formed thereby. The process includes preparing a substrate ( 12 ) for deposition of a junction layer ( 14 ); forming the junction layer ( 14 ) on the substrate ( 12 ) using hot wire chemical vapor deposition; and, finishing the semi-conductor device.
1. A process for forming a semi-conductor comprising;
preparing a substrate for deposition of a junction layer;
forming the junction layer using hot wire chemical vapor deposition to deposit the junction layer on the substrate, wherein the deposition of the junction layer is performed at a substrate temperature equal to or less than 220 C and wherein the process for forming a semi-conductor does not include an annealing or diffusion step; and
forming a passivation layer after the forming of the junction layer, the forming of the passivation layer including using a hot-wire chemical vapor deposition technique to form the passivation layer;
wherein the forming of the junction layer and the forming of the passivation layer are performed as a single operation in a single deposition chamber.
2. A process according to claim 1 further including forming a solar cell from the semi-conductor formed by the substrate with the junction layer deposited thereon.
3. A process according to claim 1 wherein in the forming operation, the junction layer deposited is one or the other of an n-type and a p-type semi-conductor.
4. A process according to claim 1 wherein in the forming operation, the junction layer deposited is one or the other of an n-type semi-conductor deposited upon a p-type substrate, and a p-type semi-conductor deposited upon an n-type semi-conductor.
5. A process according to claim 1 wherein the preparing operation includes providing a doped silicon substrate.
6. A process according to claim 1 wherein the forming operation includes forming a doped silicon junction layer.
7. A process according to claim 1 wherein the forming operation includes using a silane gas with a dopant gas to form a doped silicon junction layer.
8. A process according to claim 1 wherein the forming operation includes using a silane gas with a dopant gas to form a doped silicon junction layer, and wherein the dopant gas includes one or more of phosphine, phosphorus, arsenic or boron.
9. A process according to claim 1 wherein the forming operation includes forming a silicon-based passivation layer.
10. A process according to claim 1 wherein the forming operation includes using a silane gas with a passivation gas to form a silicon-based passivation layer.
11. A process according to claim 1 wherein the forming operation includes using a silane gas with a passivation gas to form a silicon-based passivation layer, and wherein the passivation gas includes ammonia.
12. A process according to claim 1 wherein one or both of the preparing and forming operations includes connecting a conductive contact.
13. A process according to claim 1 further including a finishing operation which includes connecting a conductive contact, and wherein the conductive contact is connected to the junction layer.
14. A process according to claim 1 further including a passivation layer forming operation and a finishing operation which includes connecting a conductive contact, and wherein the conductive contact is connected to one or both of the junction layer and the passivation layer.