An ion implanter generates and directs ions towards a target for treatment. An ion implanter may include known beam line ion implanters that generate a well defined ion beam. A beam line ion implanter includes an ion source and an is extraction electrode assembly to extract a well defined ion beam from the ion source. One or more beamline components known in the art may control and modify the ion beam to obtain an ion beam with desired characteristics which is directed towards a surface of the target. The ion beam may be distributed across a surface of the target by ion beam movement, target movement, or a combination of the two. An ion implanter may also include known plasma doping ion implanters that generate plasma in a process chamber. Ions from the plasma are attracted towards a surface of a target during certain time intervals. The target is also positioned in the process chamber of the plasma doping ion implanter. For either type of ion implanter, the target may include, but not be limited to, a semiconductor substrate, a solar cell, a polymer substrate, and a flat panel.
An ion implanter may also be equipped with a mask to provide for selected treatment of the target. A conventional mask has one or more apertures and is sized relative to the target to provide a selected treatment over an entirety of the target. Hence, an application that requires a masked and non-masked ion treatment requires one treatment with the entirety of the target masked and another treatment with the entirety of the target un-masked. One drawback with a conventional ion implanter and mask is the time necessary to move the mask away from the target in between the masked and non-masked ion treatments. This additional time negatively impacts throughput performance. Another drawback is alignment of the mask with the target. Most masking applications require precise alignment of the mask to the target. Yet another drawback is the difficulty in retrofitting an existing ion implanter with such a full sized mask including an associated alignment system to align the mask with the target.
Accordingly, there is a need for an improved masking apparatus, ion implanter, and method that overcomes the above-described inadequacies and shortcomings.