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AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsKouichirou Tsujita, Atsumi Yamaguchi, Junjiro Sakai, Kouji Oda, Koichiro Narimatsu
Estimating the term…
An antireflection coating has two-layer structure including lower and upper silicon nitride films (p-SiN films) formed by plasma CVD. For the lower p-SiN film, the real part of its complex index of refraction is set in the range not less than 1.9 nor more than 2.5, the imaginary part is set in the range of not less than 0.9 nor more than 1.7, and the film thickness is set in the range of not less than 20 nm nor more than 60 nm. For the upper p-SiN film, the real part of its complex index of refraction is set in the range not less than 1.7 nor more than 2.4, the imaginary part is set in the range of not less than 0.15 nor more than 0.75, and the film thickness is set in the range of not less than 10 nm nor more than 40 nm.
An antireflection coating provided between an underlying layer and a resist in a semiconductor device manufacturing process, said antireflection coating comprising:
A semiconductor device manufacturing method comprising the steps of:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Of dielectric parts comprising thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers: of multilayered…
Characterised by structural details, e.g. supports, auxiliary layers: characterised by antireflection means or light filtering or absorbing means,…
Characterised by the conductor: aspects related to lithography, isolation or planarisation of the conductor
For Group IV materials or Group III-V materials: characterised by their composition, e.g. multilayer masks or materials
Term ended 3 Nov 2021 (estimated)
1. Field of the Invention
The present invention relates to an antireflection coating used in a semiconductor device manufacturing process and to a semiconductor device manufacturing method including a process of forming the same.
2. Description of the Background Art
FIG. 1 is a schematic diagram used to explain the reflection of light.
FIG. 2 is a schematic sectional view used to explain a semiconductor device to which an antireflection coating according to a first preferred embodiment is applied.
FIG. 3 is a diagram showing the correlation between the imaginary part k and the real part n in the complex indices of refraction of the upper and lower p-SiN films of the first preferred embodiment.
<First Preferred Embodiment>
First, FIG. 1 is a schematic diagram used to explain the reflection of light. As shown in FIG. 1, the first and second layers 201 and 202 are in contact with each other, where the first layer 201 has a complex index of refraction (n1−i×k1) and the second layer 202 has a complex index of refraction (n2−i×k2). The characters n1 and n2 are the real parts of the complex indices of refraction, which determine the light velocity in the substance. The characters k1 and k2 are the imaginary parts of the complex indices of refraction, which correspond to the absorption coefficient of the light. A larger value of the imaginary part indicates a higher light blocking property and a smaller value of it indicates a higher transmittance. Hereinafter the complex index of refraction may simply be called an index of refraction.
Light traveling in the second layer 202 to the first layer 201 is reflected at the interface between the layers 201 and 202, where the reflectance R is given as: R = ( n 1 - n 2 ) 2 + ( k 1 - k 2 ) 2 ( n 1 + n 2 ) 2 + ( k 1 + k 2 ) 2