摘要 |
<p>A chamber (28) comprises a radiation source (58) capable of emitting radiation having a wavelength that is substantially absorbed in a predetermined pathlength in a thickness of a layer (22) on a substrate, and a radiation detector (62) adapted to detect the radiation. The radiation is substantially absorbed in a first thickness of the layer (22), and after at least partial processing of the layer (22), is at least partially transmitted through a second thickness of the layer (22) and reflected by one or more underlayers (24) of the substrate (20).</p> |