Abstract
We show that the bombardment of densified chemical vapor deposited SiO2 by hydrogen ions induces fluorescent defects. A proton dose of 6×1014 /cm2 saturates the fluorescence yield at approximately 0.6 photons/100 keV of absorbed proton energy. A beam rocking technique was used to obtain a fluorescence alignment signal corresponding to the registration of a stencil mask pattern with a corresponding SiO2 mark on a wafer. Simulation of an optimized alignment system implies that 50 nm (3σ) registration can be achieved with a 1 s settling time. This direct approach to alignment has the advantages of being simple, relatively insensitive to resist coating of the marks, and compatible with conventional integrated circuit processing.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have