| Popis: |
Currently there are no in-line TSV (through silicon via) etch profile metrology tools suitable for use in high volume manufacturing. Cross-section SEM analysis can be utilized for process development, but it is a destructive technique. In our research, a dark-field optical microscope tool is developed to in-line non-destructively measure the via profile. It is capable of measuring images with high contrast between the measuring object and the surrounding background field. As the name implies, the background is dark and the measuring object is relatively bright. Thus, a tiny structure of object can be more clearly resolved compares to the conventional bright-field optical microscope method. Analysis algorithms are developed to analyze the bottom profile and the sidewall profile of the vias separately. In this paper, vias with CDs (critical dimensions) from 30 um to 200 um are measured, and the experimental results are verified by the cross-section SEM results. |
