@inproceedings{91c7c82861084054b0e27c36173766fb,
title = "Micro projection lithography inside deep trenches using microlens on a mask",
abstract = "This paper presents a micro projection lithography process which enables the patterning of photoresist at the bottom surface of deep cavities, using microlenses formed directly on the mask. Arrays of cylindrical plano-convex microlenses on conventional photomasks have been fabricated by a photoresist melting and reflow technique, thereby augmenting the proximity lithography performance of these masks. Patterning results inside deep trenches have been analyzed. A maximum pattern width reduction of 64% for a 60μm rectangular pattern at the bottom of a 216μm-deep trench has been achieved with a microlens with a focal length of 267μm. The effect of the focal length variation on the pattern size variation has been analyzed.",
keywords = "Microlens, Projection lithography, Three-dimensional packaging",
author = "Ji, {Chang Hyeon} and Florian Herrault and Allen, {Mark G.}",
year = "2009",
doi = "10.1109/SENSOR.2009.5285691",
language = "English",
isbn = "9781424441938",
series = "TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems",
pages = "1908--1911",
booktitle = "TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems",
note = "TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems ; Conference date: 21-06-2009 Through 25-06-2009",
}