Nanoscale Coherent Diffractive Imaging of Integrated Circuit Components and Interfaces with Table-Top Extreme Ultraviolet Light

The project aims to develop new, nanoscale, non-destructive imaging techniques for semiconductor materials and devices based on ptychographic coherent diffractive imaging (CDI). Current imaging techniques may cause damage to devices, thus limiting the amount of in situ measurements on semiconductor stacks. By performing ptychographic CDI with extreme ultraviolet (EUV) light, complex objects that are comprised of the fundamental components of integrated circuits can be imaged with nanometer scale resolution. A high-harmonic generation (HHG) source will be used to produce femto-to-attosecond EUV radiation to perform these imaging experiments. Particular attention will be placed on heterogeneous samples such as photoresists coated on substrates, device stacks, and photomasks. Both transmission and reflection modes will be utilized. By varying experimental parameters, such as the wavelength of the illuminating radiation and the angle of incidence, quantitative chemical/atomic imaging (e.g., dopant profiling) of materials, devices, and stacks will also be explored. Additionally, time-resolved CDI will be explored to study processes of heat flow and the in situ dynamics of the EUV photoresist exposure mechanism.