Planarizing material for reverse-tone step and flash imprint lithography

Abstract

Reverse-toneStep and Flash Imprint Lithography (S-FIL/R) requires materials that can be spin coated onto patterned substrates with significant topography and that are highly-planarizing. Ideally, these planarizing materials must contain silicon for etch selectivity, be UV or thermally curable, have low viscosity, and low volatility. One such novel material in particular, a branched and functionalized siloxane (Si-12), is able to adequately satisfy the above requirements. This paper describes a study of the properties of epoxy functionalized Si-12 (epoxy-Si-12) as a planarizing layer. An efficient synthetic route to epoxy-Si-12 was successfully developed, which is suitable and scalable for an industrial process. Epoxy-Si-12 has a high silicon content (30.0 %), low viscosity (29 cP @ 25 °C), and low vapor pressure (0.65 Torr @ 25 °C). A planarizing study was carried out using epoxy-Si-12 on trench patterned test substrates. The material showed excellent planarizing properties and met the calculated critical degree of planarization (critical DOP), which is a requirement for a successful etch process. An S-FIL/R process using epoxy-Si-12 was demonstrated using, an Imprio ® 100 (Molecular Imprints Inc., USA) imprint tool. The results indicate that epoxy-Si-12 works very well as a planarizing layer for S-FIL/R.

Nanoimprint lithography: 2D or not 2D? A review

“…The typical pattern transfer process in NIL is the residual layer (window opening, breakthrough) etch, followed by the transfer into the substrate [106][107][108][109][110][111][112][113][114][115][116][117][118][119][120][121][122]. This can be done by anisotropic proportional etching, as long as a sufficient ''resist height budget'' is provided.…”

Ultraviolet curable branched siloxanes as low-k dielectrics for imprint lithography

“…Si-12 was synthesized as previously describe, 13,17 and methacrylate substituents were appended through a platinum catalyzed hydrosilylation to obtain MA-Si-12. Octa[(methacryloylpropyl)dimethylsilyloxy]silsesquioxane (MA-POSS) was synthesized from Octakis(dimethylsiloxy)octasilsesquioxane (available from Gelest, USA) via a platinum catalyzed hydrosilylation in toluene.…”

“…16,17 This application demands a photocurable organosilicon compound with low viscosity and low vapor pressure, a combination of properties that is not common. 16,17 This application demands a photocurable organosilicon compound with low viscosity and low vapor pressure, a combination of properties that is not common.…”

Nanoimprinting of TiO 2 –SiO 2 photocurable materials with high titanium concentration for CF 4 /O 2 etch selectivity

“…The methodology used in the above studies is useful in conducting the work reported in this Letter. In our previous studies, fluorinated SiO 2 -based resist materials and eco-friendly sugar derivative resist materials as natural compounds were developed in step and flash nanoimprint lithography [14][15][16]. However, little is known about nanoimprint lithography using TiO 2 -SiO 2 photocurable materials with high titanium concentration for CF 4 /O 2 etch selectivity with a pattern transferring carbon layer in nanoimprinting as a bi-layer process.…”