Today KLA-Tencor Corporation
introduced the die-to-database version of its latest mask inspection technology,
Wafer Plane Inspection(TM) (WPI). WPI allows leading-edge logic and foundry
mask makers to concurrently detect defects on the mask and assess whether the
defects are likely to print on the wafer. For the first time, this capability
is available for single-die reticles and multiple-die reticles with non-repeating
fields.
“Several applications will benefit from WPI’s new die-to-database
capability,” noted Zain Saidin, chief engineering officer and general
manager of KLA-Tencor’s Reticle and Photomask Inspection Division. “High-end
graphics chips and high-end programmable devices tend to be manufactured on
single-die reticles because the chips are so large. Photomasks containing different
chips for multiple customers are often utilized by foundries as a means of improving
efficiency. To facilitate faster learning during development, mask makers place
multiple versions of a die on a single reticle. Finally, some defects repeat
in the same location of every die. Die-to-die and cell-to-cell modes don’t
work in these situations. With die-to-database capability, WPI enables detection
of printable defects on all reticles—not just those with repeating structures.”
The unparalleled resolution of the images generated by KLA-Tencor’s TeraScan
reticle inspection system allows WPI to calculate not only how the light illuminates
the top surface of the photoresist on the wafer (the ‘aerial-plane image’),
but also how the photoresist responds (the ‘wafer-plane image’).
The wafer-plane image more accurately predicts which defects are likely to print
on the wafer.
Photomask makers in Taiwan, Japan and the United States have installed WPI
on their TeraScan inspection systems, and have benefited from its power to accelerate
mask development, production and qualification. WPI’s new die-to-database
capability is part of a broad portfolio of products from KLA-Tencor designed
to address the metrology and inspection issues of advanced patterning.