NOVELTY - Making an anti-reflection film of a solar cell comprises passivating the laminate with SiCNO:Ar plasma in a plasma-enhanced vapor deposition device, thus filling the dangling bonds of the silicon atoms at the surface of the n type poly-silicon emitter, the dangling bonds of the silicon grains at the grain boundaries of the p type poly-silicon light-soaking film and the dangling bonds of the silicon atoms in the p type poly-silicon back surface field; and coating the n type poly-silicon emitter with an anti-reflection film of silicon cyanide (SiCN)/silicon dioxide (SiO2).    USE - The method is useful for making an anti-reflection film of a solar cell (claimed).    ADVANTAGE - The present invention provides a method for using SiCNO:Ar plasma to passivate a poly-silicon laminate to fill dangling bonds of silicon on the surface and at internal grain boundaries, thus providing an anti-reflection film of SiCN/SiO2 for a solar cell.    DETAILED DESCRIPTION - Making an anti-reflection film of a solar cell comprises providing a laminate comprising a ceramic substrate; a titanium-based compound film coated on the ceramic substrate; a p type poly-silicon back surface field coated on the titanium-based compound film in a high-temperature atmospheric pressure chemical vapor deposition system; a p type poly-silicon light-soaking film coated on the p type poly-silicon back surface field in the high-temperature atmospheric pressure chemical vapor deposition system; and an n type poly-silicon emitter coated on the p type poly-silicon light-soaking film; passivating the laminate with SiCNO:Ar plasma in a plasma-enhanced vapor deposition device, thus filling the dangling bonds of the silicon atoms at the surface of the n type poly-silicon emitter, the dangling bonds of the silicon grains at the grain boundaries of the p type poly-silicon light-soaking film and the dangling bonds of the silicon atoms in the p type poly-silicon back surface field; and coating the n type poly-silicon emitter with an anti-reflection film of SiCN/SiO2.