Neodymium micro magnets are commonly founded in both injection molded magnets and compression molded magnets because of the binder is more flexible, but in reality, the material of micro magnet has been already expanded to ferrite magnets, Neodymium magnets, Samarium Cobalt magnets, and AlNiCo magnets. Neodymium miniature magnets are generally offered in micro disc magnets, micro block magnets, and micro ring magnets. Magnetic performance of sintered Neodymium magnets will be deteriorated after machining process, and this is largely due to the nucleation of magnetization reversal which generated by surface oxidation and structural deformation. For Neodymium tiny magnets, damaged area occupies the much larger proportion of the whole volume, that is to say, magnetic performance of Neodymium miniature magnets decreases as the dimension declines. Sagawa found that coercivity of such Neodymium tiny magnets restored after introduced Dy film to the surface and processed a heat treatment. This work is also considered as an illuminating thinking to subsequent grain boundary diffusion (GBD) magnets. Besides conventional metal coating like Nickel or Zinc, biocompatible Parylene coating is also suitable for Neodymium mini-sized magnets. SDM has the capability to ensure tolerance in the range of +/-0.005mm to +/-0.020mm via advanced laser incising and drilling technology.