TEXTURING FOR HETEROJUNCTION SILICON SOLAR CELLS

ABSTRACT: Heterojunction solar cells have potential for very high device voltages and currents, yet this relies on correct preparation of wafer surfaces prior to a-Si deposition. This paper investigates the preparation of wafer surfaces by NaOH texturing prior to amorphous silicon intrinsic layer deposition. It is found that with a CP etch or low temperature anneal after texturing, and with correct deposition parameters, effective wafer lifetimes in excess of 1 ms can be achieved, indicating excellent surface passivation. Low reflectance achieved following wafer texturing along with high wafer lifetime led to efficiencies in finished devices as high as 17.6%