The invention relates to the technical field of
photovoltaics, and discloses a back contact photovoltaic
cell and a preparation method thereof. The preparation method comprises the following steps: performing
laser grooving on an N region and a P region on the back surface of a
silicon wafer by adopting
infrared laser to form a first cambered surface groove and a second cambered surface groove respectively; after the
laser damage layer is removed, an
amorphous silicon layer is deposited on the back surface of the
silicon wafer; respectively printing N-type doped
slurry and P-type doped
slurry in the first cambered surface groove and the second cambered surface groove in the back surface of the
amorphous silicon layer; aerobic annealing is carried out, so that the
amorphous silicon layers at the first cambered surface groove and the second cambered surface groove are converted into N +
polycrystalline silicon and P +
polycrystalline silicon respectively, and protection
layers are formed on the back surfaces of the N-type doped
slurry and the P-type doped slurry; and after the protective layer and the N and P type doped slurry are removed, plating a
passivation film, and performing metallization to prepare an N type
electrode and a P type
electrode which are in contact with the N +
polycrystalline silicon and the P + polycrystalline
silicon respectively. According to the preparation method, the BC
cell production process can be simplified, the productivity can be improved, the production cost can be reduced, the carrier collection efficiency can be improved, the back light receiving area can be increased, the series resistance can be reduced, and the
photoelectric conversion efficiency and the double-sided rate can be improved.