2.3 Target Materials Properties

For ion implantation it is very important to distinguish between single crystalline materials, poly-crystalline materials, which consist of small crystals, called grains and amorphous materials, because the isotropy of the material has a strong influence on the penetration depth of the implanted particles. A semiconductor device consists of several materials, a crystalline semiconductor substrate (in this work only silicon is considered), poly-crystalline semiconductor layers, amorphous isolation layers (silicon dioxide, silicon nitride) and amorphous metal layers (aluminum, copper). The following sections summarize the physical properties related to ion implantation of the most important materials.