Sputtering is one of the most widely used techniques for depositing thin films. The target is a plate of the materials to be deposited or the material from which a film is synthesized. Because it is connected to the negative terminal of a dc or RF power supply, the target is also known as the cathode. Typically, several kilovolts are applied to it. The substrate that faces the cathode may be grounded, electrically floating, biased positively or negatively, heated, cooled, or some combination of these.
