Abstract
A single thick layer of poly(vinyl phenol) containing onium salt was surface-silylated uniformly through contact with hexamethyl-cyclotrisilazane or hexamethyl-disilazane in solution to obtain a bilevel structure, similarly to a previous silylation study in the vapor phase. Silicon atoms were effectively incorporated into the surface sublayer by limited permeation of the solute and reaction with -OH to form -O-SiR3. The O2 reactive ion etching (RIE) durability of the silylated sublayer of 170-220 nm thickness was 15-38 times as high as that of the unsilylated bulk layer. The resist layer was patterned by 5-10 mJ/cm2 deep ultraviolet exposure, chemically amplified desilylation during postexposure baking, and wet development with alkali to remove the surface sublayer in the exposed area, forming a shallow, recessed image. When the layer, particularly that silylated with hexamethyl-disilazane, was plasma-developed by O2 RIE, the bulk layer in the exposed area was clearly blanked to the substrate to give a positive-tone image with a high aspect ratio.
Original language | English |
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Pages (from-to) | 6658-6662 |
Number of pages | 5 |
Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
Volume | 40 |
Issue number | 11 |
State | Published - 1 Nov 2001 |
Keywords
- Alkaline development
- Bilevel structure
- Plasma blanking
- Positive image
- Pre-exposure silylation
- Top surface imaging