Magnetron Molybdenum Sputtering Target
Magnetron molybdenum sputtering target purity is 99.95% and density is 10.2g/cm3. The melting point of it is 2610℃ and boiling point is 5560℃. The types of it include rectangle magnetron molybdenum sputtering target, rotatable magnetron molybdenum sputtering target and cylindrical magnetron tube molybdenum sputtering target. Magnetron molybdenum sputtering target has a lot of advantages such as high strength, high temperature resistance, wear resistance, corrosion resistance and other advantages. So it is widely used in two-dimensional display, thin-film solar cells, wiring material and barrier material of semiconductor.
The operating principle of magnetron molybdenum sputtering target is that electron affected by electric field so the electron in the process of flying to substrate will crash with argon ion to produce new ion. Then the new ion fly to substrate but due to affected by electric field so argon ion fly to cathode target and hit surface of target with high strength to make target sputtering.
During sputtering particle, the neutral target ion or molecule will depose in the substrate to form films. And secondary electron which produce in the process affect by the electric filed and magnetic field drifting direction toward E (electric filed) × B (magnetic filed) called E×B drifting and the movement locus is similar to a cycloid of magnetron sputtering. If the magnetic field is toroidal then the electron will do circling motion at the target surface in cycloid form. So the motion path not only long but also constraint in the plasma region which near with the target surface. In this region ionize lots of argon ions crashing target to realize high deposition rate. With the collision number increase the powder of secondary electron use up and far away from target surface to finally deposit in the substrate by electric effect. Due to the power of electron is little so the power delivers to substrate little as well then substrate temperature rise is low.
Magnetron molybdenum sputtering target is the process of incidence particle and target collision. Incidence particle will go through complicate process during scattering and it will crash with target ion to pass some momentum to target ion. Then the target ion crash with other target ion to form cascade process. In this cascade process some target ion which near surface will get enough momentum to leave the target by sputtering.
Magnetron molybdenum sputtering target’s use rate can be a parameter of magnetron sputtering source engineering design and production cost accounting. Until 2012, there were a few professional and system report about use ratio of magnetron molybdenum sputtering target so to discuss the approximate calculation of target has importance significant. For static rectangle direct-cooling plane sputtering target which is mean there are not relative movement between target and magnet and target material can direct contact with cooling water. Besides, the use ratio of it is about 20%~30% (maximum). In order to improve target’ use ratio so has done a lot of researcher on different form dynamic target and the rotatable magnetron cylinder target was known and widely used in industry. It is said that this target use ratio more than 70% but without enough research data and theoretical identification.