1.The major metal minerals recycled include tantalum niobite, fine spar, tantalum aeschynite, wolframite and scheelite, which have large density of generally 5 to 7.
7.That is possible because this part of the transistor is made of tantalum pentoxide, a material whose atoms are arranged in a lattice which contains holes large enough for copper atoms to squeeze through.
8.But essentially there are 3 key groups of materials that are added or deposited onto the wafer: metals such as copper or tantalum, insulators which are typically called oxides, and crystalline layers of silicon.