Homogeneous deposition of high purity silicon thin films with highest rates above 30 µm/min

We demonstrate currently reached results for depositing silicon thin films by crucible-free electron beam physical vapor deposition (EB-PVD). The feasibility of a crucible-free EB-PVD could successfully be demonstrated in experiments with different configurations of evaporation material. The process could be improved regarding the critical aspects, e.g. occurrence of cracks during heating up and spill out of the melt on the melting pool edges. Deposition rates above 500 nm/s, corresponding to 30 mm/min, have been reached. By using a double-ingot arrangement and superposing vapor from multiple sources the relative deviation of layer thickness could be reduced to < ±5 % on a substrate width of 200 mm (8 ). Furthermore, we investigated impacts of process parameters on layer stress.