| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

Glossary of Lithography Terms - Q


Quadrupole Illumination A type of off-axis illumination where four circles or arcs of light are used as the source. These four circles are spaced evenly around the optical axis.

Example: Quadrupole illumination is especially useful for improving the depth of focus of small dense lines oriented in the x- or y-directions.


Quantum Efficiency Referring to photoresist exposure, the quantum efficiency is the average number of exposure reaction products produced when one photon is absorbed by the photoreactive species.

Example: Reasonably good photoacid generators show quantum efficiencies of about 0.5.