| abstract |
System and method for controlling the thickness profile of deposited thin film layers over three-dimensional topography are disclosed, wherein low pressure chemical vapor deposition conditions are employed with the reactant beam collimated and chosen to impinge at a specific angle onto the surface, such that the reactive sticking coefficient s r with the deposition surface is <1. Compared with conventional approaches, this method permits new shapes of the deposited thin film layer to be achieved over topography (such as trenches), including (i) tapered rather than re-entrant shapes (i.e., thicker at bottom rather than at top), (ii) enhanced sidewall and/or bottom coverage of trench structures (cf. the top surface), (iii) voidless, seamless filling of trench or via structures even at high aspect ratio (depth/width), and (iv) asymmetric sidewall coverage. |