Abstract
We observe that under certain conditions, hydrogenated amorphous silicon grown by the hot-wire chemical-vapor deposition technique has dark conductivities varying by several orders of magnitude across the same film. Similarly, the ambipolar diffusion lengths fluctuate significantly in these films, yet there is not much evidence of a corresponding structural change. We attribute this electronic nonuniformity to electrons from the filament reaching insulating substrates and charging the substrate negatively in some regions, thus causing films to grow with inferior material properties in those regions. The effect diminishes with increasing substrate temperature, where the film itself may be conductive enough to remove charge reaching the growing surface. Well-grounded, conducting substrates seem to be immune from this effect. We reduce this effect by putting a conductive grid on insulating substrates, of close enough spacing to remove the charge, and measure the material properties of the film grown between the conductive elements of the grid.
Original language | American English |
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Pages | 927-932 |
Number of pages | 6 |
State | Published - 1999 |
Event | Proceedings of the 1998 MRS Spring Meeting - San Francisco, CA, USA Duration: 14 Apr 1998 → 17 Apr 1998 |
Conference
Conference | Proceedings of the 1998 MRS Spring Meeting |
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City | San Francisco, CA, USA |
Period | 14/04/98 → 17/04/98 |
NREL Publication Number
- NREL/CP-520-24525