摘要:
An integrated sputtering method and reactor for copper or aluminum seed layers in which a plasma sputter reactor initially deposits a thin conformal layer onto a substrate including a high-aspect ratio hole subject to the formation of overhangs. After the seed deposition, the same sputter reactor is used to sputter etch the substrate with energetic light ions, especially helium, having an energy sufficiently low that it selectively etches the metallization to the heavier underlying barrier layer, for example, copper over tantalum or aluminum over titanium. An RF inductive coil generates the plasma during the sputtering etching while the target power is turned off. A final copper flash step deposits copper over the bare barrier field region before copper is electrochemically plated to fill the hole. The invention also includes a simultaneous sputter deposition and sputter etch, and an energetic ion processing of the copper seed sidewall.
摘要:
An integrated sputtering method and reactor for copper or aluminum seed layers in which a plasma sputter reactor initially deposits a thin conformal layer onto a substrate including a high-aspect ratio hole subject to the formation of overhangs. After the seed deposition, the same sputter reactor is used to sputter etch the substrate with energetic light ions, especially helium, having an energy sufficiently low that it selectively etches the metallization to the heavier underlying barrier layer, for example, copper over tantalum or aluminum over titanium. An RF inductive coil generates the plasma during the sputtering etching while the target power is turned off. A final copper flash step deposits copper over the bare barrier field region before copper is electrochemically plated to fill the hole. The invention also includes a simultaneous sputter deposition and sputter etch, and an energetic ion processing of the copper seed sidewall.
摘要:
A lift mechanism for and a corresponding use of a magnetron in a plasma sputter reactor. A magnetron rotating about the target axis is controllably lifted away from the back of the target to compensate for sputter erosion, thereby maintaining a constant magnetic field and resultant plasma density at the sputtered surface, which is particularly important for stable operation with a small magnetron, for example, one executing circular or planetary motion about the target axis. The lift mechanism can include a lead screw axially fixed to the magnetron support shaft and a lead nut engaged therewith to raise the magnetron as the lead nut is turned. Alternatively, the support shaft is axially fixed to a vertically moving slider. The amount of lift may be controlled according a recipe based on accumulated power applied to the target or by monitoring electrical characteristics of the target.