Method for preparing packages of semiconductor, and cutting unit

The method for preparing packages of semiconductor includes steps: providing a base plate module with multiple units of base plate; forming packaging colloid for cladding chip of semiconductor on the module chip of the base plate; through a cutting unit with side mill, programmable controlling cutting path of the side mill in order to satisfy needed shape appearance. The cutting unit includes a side mill, and a control module capable of controlling the cutting path. The disclosed method can form packages in shapes of easement, flattening or irregular shapes. The invention avoids increasing cost, or complexity, and issue of environment pollution such as dust and fine sand etc. caused by using water knife or laser. Advantages are: raising service life and reducing cost of cutting tool, lowering consumption, and capable of forming packages of semiconductor in card type without body case.