1 results about "Seed crystal" patented technology

The invention discloses a forming method of a flash memory unit. The forming method comprises the following steps: providing a semiconductor substrate; forming a tunneling oxide layer on the semiconductor substrate; forming nanocrystalline silicon particles on the tunneling oxide layer; forming an isolation insulating layer on the tunneling oxide layer and the nanocrystalline silicon particles; and forming a control grid on the isolation insulating layer, wherein the step of forming the nanocrystalline silicon particles on the tunneling oxide layer comprises: forming an amorphous silicon layer on the tunneling oxide layer; and performing repeated seed crystal particle forming processes on the amorphous silicon layer, wherein surface annealing treatment is performed between two adjacent seed crystal particle forming processes, and an annealing process is performed after the last seed crystal particle forming process. The flash memory unit can be used for storing a large quantity of electrons, and has high performance.