P-N JUNCTION FORMATION TECHNIQUES
Abstract
Final tests were made on all p-on-n cells implanted investigation of effects of junction depth on cell performance. Indications are that it will be possible to produce cells having a good match to the solar spectrum by reducing junction depth. Cells with junction depths of 0.76 micron have a spectral response peak at 7500 Angstroms (equal energy input) vs. the usual 8500 Angstrom peak for diffusion produced p-on-n-type cells. Cell efficiency was raised to the 7-8% range under 2800 K tungsten illumination. This improvement is apparently due to changes in junction profile. It was shown that high oxygen content (> 10 to the 15th power O atoms/cc is an important factor in reducing cell performance. Reflection electron diffraction studies indicate that lattice damage caused by implantation is completely repaired with 800 C annealing for 16 hours. This heat treatment has no effect on bulk lifetime. Initial investigations on n-on-p cells were made by bombarding 0.4 ohm-cm p-type silicon with phosphorus ions. Results on unfinished cells are analogous to those for p-on-n cells.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1963
- Accession Number
- AD0406704