Influence of RF power on c-Si surface passivation by amorphous a-SiC/sub x/:H layers deposited by PECVD

Surface passivation of p-type crystalline silicon (c-Si) wafers has been achieved by depositing phosphorus-doped amorphous silicon carbide films (a-SiC/sub x/:H) in a PECVD reactor. We explored the dependence of effective surface recombination velocity (S/sub eff/) on the RF power supplied to the reactor during film deposition. The effective lifetime (/spl tau//sub eff/) as a function of excess carrier concentration (/spl Delta/n) was measured by quasi steady state-photoconductance (QSS-PC) technique in order to extract the surface recombination rate. We fitted the experimental /spl tau/eff(/spl Delta/n) curve by an insulator/semiconductor model resulting in the determination of the fixed charge density at the interface (Q/sub f/) and the fundamental recombination velocity of holes (S/sub po/). Additional experiments to determine the uniformity of the films along the PECVD reactor plate were carried out.