San Jose, CA — Olympus Integrated Technologies America, Inc. (Olympus-ITA) has introduced its latest 3DIR Metrology and Defect Review System. The system uses confocal IR laser scanning microscopy technology for measuring post-bond parameters of three-dimensionally stacked integrated circuits (3DS-ICs).
|3D infrared metrology system. |
Confocal IR laser scanning microscopy is a non-destructive, through-silicon metrology technique that monitors a variety of post-bond parameters — overlay alignment accuracy, bonding interface thickness variations, and bonding interface quality including pre- and post-bond defect inspection and review.
Automated measurement of a sampling of bonded wafer overlay alignment points will quickly characterize the wafer bonding alignment accuracy as well as provide indications of bond quality problems. The company's DIR metrology system measures alignment points at selected die of bonded wafers, stores images and data, and summarizes results. Correlation of overlay alignment offset data to electrical yield provides the customer with an early indication of bonded wafer yield. Software tools are provided to display data in the form of vector maps for further review and analysis.
The confocal capability of the microscope allows thin optical sectioning in Z and construction of 3D images of the bonded wafer interface and structures. The 3D reconstructions can be used to create sections in the XZ plane to provide a measurable profile of an imaged structure or feature. Using the confocal capability of the microscope to take XZ measurements at various points on the wafer provides information on the bond interface thickness uniformity. Using the system's IR microscope imaging capability, bonded wafers are automatically scanned at low magnification. Images are stitched together to form a single wafer image. When the overlay vector map is superimposed on the scanned wafer image, correlation of many of the failed overlay measurement points to bonded interface anomalies can be seen.
Because the wafer scan is done using an IR microscope, the stitched image can be viewed and zoomed for more detail. In addition, any site can be revisited and the image reviewed or rescanned and imaged using the IR microscope with objective magnifications up to 90X and 0.14µm pixel resolution.
Contact: Olympus Integrated Technologies America, Inc., 180 Baytech Drive, San Jose, CA 95134 408-514-3918 fax: 408-946-3841 firstname.lastname@example.org Web: http://www.olympus-ita.com