Semiconductor imaging solutions

With their multiple layer architecture and the increasing demand to generate more yield (usable devices per wafer), semiconductor wafer inspection demands minimal wafer handling and versatile, high quality imaging using a microscope designed specifically for wafer inspection, such as the Olympus MX Series of inspection microscopes.

In-process semiconductor inspection requires special attention to several critical steps in the manufacturing flow. The most important areas are the after photo inspection, after etch inspection, and general process review.

The photo area of the process normally requires a few key inspection steps.The most basic is the verification of the correct layer being printed, and also to verify that the resist has been effectively removed. Sometimes, it is also necessary to do some basic alignment check by imaging the test die that were made on each wafer. Another helpful technique performed during the piloting of new process is the inspection for extra photo resist. All of these techniques can be done with any of the MX series inspection microscopes.

The etch area also has some important optimal inspection requirements to determine if the etch has been successful; for example, looking inside the wells to see if the etching was complete with no evident defects. Additional checking is done to see if the etch process has gone out of control causing "over-etch", where lines or smaller structures have been broken. An inspection microscope such as our MX Series is ideal for this because the inspections need to be carried out over the entire surface of the wafer on both active and test die.

If you need to perform mask or reticle inspection to detect large-scale defects on masks your microscope must be equipped with transmitted light capabilities to provide excellent contrast and to visualize those defects. In addition, long working distance objectives (optics) are required to prevent touching or damaging the protective pellicle. The microscope also must also have the correct mask holder to prevent contamination and offer fail-safe free transfer of masks on and off the microscope.

The MX Series microscopes and the AL110 Autoloaders to automate the wafer loading process and minimize handling are both highly reliable and ergonomic wafer handling and visual inspection tools for wafer of most thicknesses and sizes from 50mm to 300mm.

LEXT – ideal for next-generation micro fabrication devices like MEMS, for new materials development, and for today’s thinner devices, with more compact surface mounting requirements.

In addition, Olympus’ LEXT OLS-3000 Laser Confocal microscope can provide high-resolution 3D images as well as precise measurements to meet the metrology needs of today’s fabs. Also offered in this line is the OLS-3000 LEXT IR tool providing laser confocal inspection through silicone.

Olympus Industrial America has launched LEXT OLS3100, a new Confocal Laser Scanning Microscope designed for sub-micron imaging, with outstanding 0.12um resolution and accurate three-dimensional measurement capability.

Olympus LEXT OLS-3100 Winner Of 2008 Semiconductor International Magazine’s Editors’ Choice.

With inspection options such as backside macro inspection, manual or motorized stages, DUV, I/R, Confocal, DIC imaging, and Auto-focus, Olympus can configure a system that meets or exceeds the most demanding wafer inspection requirements.

Whether during the etch and deposition process where higher magnifications are required, or pre-package inspection where lower magnifications are typically used, the MX series and AL110 offer the imaging and wafer handling capabilities needed for critical wafer inspection.