Sputter deposition for semiconductor manufacturing

Sputter deposition, also known as physical vapor deposition, or PVD, is a w idely used technique for depositing thin metal layers on semiconductor wafe rs. These layers are used as diffusion barriers, adhesion or seed layers, p rimary conductors, antireflection coatings, and etch stops. With the progre ssion toward finer topographical dimensions on wafers and increasing aspect patios, the broad angular distribution of depositing, sputtered atoms lead s to poor or nonexistent coverage in deep features. This has been partially addressed using directional sputtering techniques such as collimated sputt ering or long-throw sputtering, More recently, work originating in IBM has moved toward the deposition of films from metal-rich plasmas fed by sputter ing, a technique known as I-PVD (for ionized PVD), This technique, based on fairly minor modifications of existing PVD systems, solves many of the int rinsic problems of PVD and appears headed for widespread manufacturing appl ications.