Radio-frequency coil for use in an ionized physical vapor deposition apparatus

DETAILED DESCRIPTION The present invention addresses the above-described need by providing a cooling structure and/or a reinforcing structure for an RF coil in which deformation of the RF coil due to thermal expansion is reduced or avoided.
In accordance with a first aspect of the present invention, a cooling structure including a portion for carrying coolant is provided for the RF coil; the cooling structure is proximate to the RF coil along the outer circumference thereof.
The cooling structure is at a lower temperature than the RF coil, and may have thermal expansion properties different from those of the RF coil.
Furthermore, the cooling structure is shaped relative to the RF coil so that thermal expansion of the RF coil causes the RF coil to be in close contact with the cooling structure, thereby facilitating heat transfer from the RF coil to the coolant.
The RF coil also may be demountable from the cooling structure.
The cooling structure is shielded by the RF coil from sputtering during the IPVD process.
In accordance with a second aspect of the invention, a reinforcing structure is provided which gives mechanical reinforcement for the RF coil.
The reinforcing structure is proximate to the RF coil along the outer circumference thereof.
The reinforcing structure and the RF coil are of materials having different thermal expansion properties and are shaped so that thermal expansion of the RF coil causes the RF coil to be in close contact with the reinforcing structure.
Furthermore, the cooling structure may be shaped to provide mechanical reinforcement for the RF coil, so that the cooling structure and the reinforcing structure are integrated.
In accordance with another aspect of the invention, the RF coil (or cooling or reinforcing structure) is mounted on a fixed portion of the IPVD device by a mounting post having a first portion and a second portion slidably connected thereto.
This arrangement permits the mounting post to telescope in accordance with thermal expansion of the RF coil