A solar cell, comprising: a substrate having a front surface and a back surface opposite to the front surface; a first passivation layer, a second passivation layer and a third passivation layer sequentially formed on the front surface of the substrate and in a direction away from the substrate; wherein the first passivation layer includes a dielectric material; the second passivation layer includes a first silicon nitride material, and a ratio of a number of nitrogen atoms to a number of silicon atoms in the first silicon nitride material is in a range of 1.3 to 1.7; and the third passivation layer includes a silicon oxide material, and a ratio of a number of oxygen atoms to a number of silicon atoms in the silicon oxide material is in a range of 1.9 to 3.2; and a tunneling oxide layer and a doped conductive layer sequentially formed on the back surface of the substrate and in a direction away from the back surface, wherein the doped conductive layer and the substrate are doped to have a same conductivity type; characterized in that the third passivation layer includes a first silicon oxide sub-layer, a second silicon oxide sub-layer, and a third silicon oxide sub-layer stacked in the direction away from the substrate, wherein the first silicon oxide sub-layer, the second silicon oxide sub-layer, and the third silicon oxide sub-layer each includes a silicon oxide material, and refractive indices of the first silicon oxide sub-layer, the second silicon oxide sub-layer, and the third silicon oxide sub-layer gradually decrease; and wherein a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the first silicon oxide sub-layer is in a range of 1.9 to 2.2, a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the second silicon oxide sub-layer is in a range of 2.2 to 2.7, and a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the third silicon oxide sub-layer is in a range of 2.7 to 3.2. a substrate having a front surface and a back surface opposite to the front surface; a first passivation layer, a second passivation layer and a third passivation layer sequentially formed on the front surface of the substrate and in a direction away from the substrate; wherein the first passivation layer includes a dielectric material; the second passivation layer includes a first silicon nitride material, and a ratio of a number of nitrogen atoms to a number of silicon atoms in the first silicon nitride material is in a range of 1.3 to 1.7; and the third passivation layer includes a silicon oxide material, and a ratio of a number of oxygen atoms to a number of silicon atoms in the silicon oxide material is in a range of 1.9 to 3.2; and a tunneling oxide layer and a doped conductive layer sequentially formed on the back surface of the substrate and in a direction away from the back surface, wherein the doped conductive layer and the substrate are doped to have a same conductivity type; characterized in that the third passivation layer includes a first silicon oxide sub-layer, a second silicon oxide sub-layer, and a third silicon oxide sub-layer stacked in the direction away from the substrate, wherein the first silicon oxide sub-layer, the second silicon oxide sub-layer, and the third silicon oxide sub-layer each includes a silicon oxide material, and refractive indices of the first silicon oxide sub-layer, the second silicon oxide sub-layer, and the third silicon oxide sub-layer gradually decrease; and wherein a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the first silicon oxide sub-layer is in a range of 1.9 to 2.2, a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the second silicon oxide sub-layer is in a range of 2.2 to 2.7, and a ratio of a number of oxygen atoms to a number of silicon atoms of the silicon oxide material of the third silicon oxide sub-layer is in a range of 2.7 to 3.2.