Solar cell and preparation method thereof

The invention relates to the field of photovoltaic technology, in particular to a solar cell and a preparation method thereof. Comprising the following steps: providing a textured N-type silicon wafer; boron slurry is printed on the front face of the N-type silicon wafer and dried; boron expansion junction pushing is carried out on the N-type silicon wafer printed with the boron slurry under the heating and oxygen-free conditions, so that a P-N junction with a heavily doped region and a lightly doped region at the same time is formed on the front face of the N-type silicon wafer; cleaning the N-type silicon wafer subjected to boron expansion junction pushing by using an acid solution; heating and oxidizing the front surface of the cleaned N-type silicon wafer to form a first borosilicate glass layer; and performing post-treatment to obtain the solar cell. Therefore, the problems of silicon wafer damage, electric leakage failure, complex process and the like can be solved, the yield and the stability are ensur