Circulating tumor cell clusters (CTCCs) are significantly more likely to form metastases than single tumor cells. We demonstrate the potential of backscatter-based flow cytometry (BSFC) to detect unique light scattering signatures of CTCCs in the blood of mice orthotopically implanted with breast cancer cells and treated with an anti-ADAM8 or a control antibody. Based on scattering detected at 405, 488, and 633 nm from blood samples flowing through microfluidic devices, we identified 14 CTCCs with large scattering peak widths and intensities, whose presence correlated strongly with metastasis. These initial studies demonstrate the potential to detect CTCCs via label-free BSFC.

No abstract

As optical lithography approaches the 0.25 im performance 1eve1, overlay performance approaches 75 nanometers (mm). This in turn requires alignment systems to work to tighter budgets. This paper presents the theory ofoperation behind the AXIOM off-axis alignment system. We have examined the advantages ofusing the AXIOM system, and have implemented a trade-offstrategy. Our discussion includes an overview ofthe AXIOM alignment sensor head (sensor head) system. We also provide the benefits ofthe sensor's broadband incoherent light source illumination when used to achieve process insensitivity. In addition, we provide the benefit ofbeing a bright and dark field system. We perfonned modeling to evaluate how various alignment targets interact with illumination. Modeling assessments highlighted the advantages of separately detecting the left and right diffiacted orders ofa target. The sensor head can examine a target by using both bright field, left and right orders simultaneously. Examining a target helps us obtain more information and further reduces process sensitivity. Finally, we verified performance with multilevel data and compared it to industry standards.