Abstract: A method for preparing a grounding substrate for a semiconductor device, the method including: 1) polishing the surface of a matrix of a grounding substrate to remove a carbon layer therefrom, and washing the surface of the matrix with anhydrous ethanol; 2) providing a cold spray system including a spraying device, a spray chamber, and a special fixture disposed in the spray chamber; and disposing the matrix on the special fixture; 3) using the cold spray system to spray a compressed gas carrying aluminum powder on the surface of the matrix at the supersonic speed to form an aluminum coating, thus obtaining the grounding substrate; 4) disposing the grounding substrate in a heat treatment furnace, raising the temperature therein to between 100 and 500° C., and maintaining the temperature for between 1 and 5 hrs; and 5) wet polishing the grounding substrate.