Optically matched trilevel resist process for nanostructure fabrication

Abstract

A novel trilevel resist process has been developed which enables high-contrast imaging of periodic structures with spatial periods down to 200 nm in thick resist on highly reflective substrates, using ϭ351.1 nm argon-ion laser exposure. The process utilizes a 200-nm-thick, high-contrast, imaging resist layer, a thin ͑ϳ15-nm͒ evaporated dielectric interlayer, and a 300-600-nm-thick bottom antireflection coating ͑ARC͒ which suppresses reflections from the substrate. Our trilevel resist scheme has been implemented in a manufacturing process which utilizes a high-contrast interferometric lithography system for the formation of large-area, 200-1000 nm period grating and dot array images. The choice of interlayer is the most critical feature of this process. This material must have good deposition and adhesion properties, must be optically matched to the resist and ARC, must etch quickly during the reactive-ion etching ͑RIE͒ pattern transfer from the resist into the interlayer, must display very high selectivity to the ARC during the RIE pattern transfer into the bottom layer, and must be easily stripped after the trilevel resist structure has served its purpose. We also report on computer modeling which elucidates the factors influencing standing wave formation and present results of tests with several interlayer materials which display good optical matching and selectivities of up to 240:1 during RIE of the ARC.

Fabrication of patterned magnetic nanodots by laser interference lithography

“…In the work reported here, XHRi-16 (produced by Brewer Science, Inc.) was used as an ARC. In order to be able to transfer the PR pattern through the ARC layer, a Trilevel Resist Process can be applied [8]. In this process a hard etch mask is deposited between the ARC and the PR.…”

Fabrication of nanoscale plasmonic structures and their applications to photonic devices and biosensors

“…Furthermore, it allows mass production of particle arrays in large and uniform areas at a much lower cost compared to the EBL method [38,39]. LIL can be simply performed using Lloyd's configuration [40]. The Lloyd holder is attached on a rotating stage with a high angle precision to have a fine control of the periodicity.…”

Laser precision engineering: from microfabrication to nanoprocessing

“…The plasmon resonance properties of the metallic structures fabricated can be modified by this simple sample-rotation approach [91]. After the transfer of the nanopatterns by chemical etching or lift-off, this nanostructure can be used for the patterned media in high-density data storage, microsieves for microfiltration and submicrometer perforated membranes, nanotemplate for self-assembly and field emission flat-panel displays [92][93][94].…”