Zero-Footprint Optical Metrology Wafer
John Gerling and Nathan W. Cheung
Using a heterogeneous integration approach, we have encapsulated prefabricated monolithic components, a photodiode, and LED inside a silicon wafer form factor to achieve a self-contained, environmentally sealed system. We have demonstrated the utility of the metrology wafer for data mapping and process monitoring in hostile environments such as plasma, CMP, and chemical etching. Our work now focuses on quantitative verification of copper end-point etching and lateral feature monitoring with modeling. We are also working on prototyping data acquisition and extending the capability of the zero-footprint optical metrology wafer to include spectroscopy. We are exploring potential application areas in biology and chemical detection.