ION-BEAM ANALYSIS OF PLASMA IMMERSION IMPLANTED SILICON FOR SOLAR-CELL FABRICATION

Phosphorus ions were implanted using plasma immersion ion implantation (PII) to create shallow pn junctions in solar cells. Depths of PII ph osphorous were shallow enough to be analyzed by Rutherford Backscatter ing Spectrometry (RBS) combined with the channeling technique. It was shown that PII is able to produce a high enough surface concentration of phosphorous (several times 10(21) cm(-3)) for shallow pn junctions. RBS revealed that after 5 minutes of implantation phosphorus surface concentrations remained almost unchanged due to the balance of implant ation and surface sputtering. A heavily damaged layer was found at the surface, the thickness of which was comparable to the range of the co -implanted hydrogen depth profile, Electrical activation of the implan ted phosphorus and junction depth measured by Spreading Resistance Pro filing (SRP) were favourable for short time PII of about 1-5 minutes.