X-ray dose density: a new radiation damage modeling tool (Poster Paper)

摘要

We report on a new modeling tool for the prediction of the cumulative dose delivered to any given layer of a semiconductor process involving x-ray lithography (XRL) steps. In such a process, the layers receive various doses at different steps in the manufacturing. In order to determine the total dose delivered at any given level it is necessary not only to compute the dose for the lithographic step of that particular level, but also to keep track of the past history of the process in order to accumulate the total radiation. For this, one must know the full process, including sacrificial layers, resist layers and layout geometries, since different areas of the surface being patterned will receive different doses because of shielding by other layers. We apply the model to the case of a standard 0.5 $mu@m NMOS device process and to an advanced 0.1 $mu@m NMOS process. Results will be presented and discussed in detail, for the various assumptions of the lithographic process. The program, written in C under UNIX, is compatible with standard process modeling tools and device layouts.