Proximity effect (electron beam lithography)

About: Proximity effect (electron beam lithography) is a research topic. Over the lifetime, 940 publications have been published within this topic receiving 8508 citations.

Reactive Ion Etching of Multi-Layer Resist

Abstract: Multi-layer resist has been utilized commonly in optical and E-beam lithography for its ability to resolve submicron feastures over topography. In addition, the use of a low-Z(atomic number) material as the intermediate layer reduces the proximity effect. This paper describes the development of etching process used to pattern a tri-level resist based on polyimide, an inorganic intermediate layer, and positive resist as top image layer. A highaspect-ratio image can be anisotropically transfered from the inorganic intermediate layer into the polyimide planarizing layer by oxygen RIE. Directionality, profile control, and backsputtering residue are the primary considerations during the pattern transfer etching. The influence of pressure, power and self-bias voltage on the etching process are described. The residue is caused by sputtering of the electrode material and the etch barrier material. Backsputtering residue from electrode can be prevented by covering all exposed conducting surfaces with an organic dielectric material, in this case an ardel plate. Etch residue contributed by the intermediate layer is quantified according to its pattern density and the influence of the pressure. Sidewall profiles and their relationship to planarizing layer thickness are also discussed.

Inspection method of resist pattern

Abstract: PURPOSE:To precisely inspect the sectional shape of a resist pattern, without breaking a substrate, by a method wherein a punched-out test pattern after lithography is inclined, and, in this state, the section of a resist pattern is exposed and inspected. CONSTITUTION:A convex type punched-out test pattern composed of a pattern part 13 for managing dimension and a rectangular pattern part 14 whose width and depth in contact with the end portion of the pattern part 13 are, e.g. 10mum, in which test pattern proximity effect to an electron beam is taken into account is subjected to lithography irradiation of a resist pattern by an ordinary substrate resist forming process. In the state that the punched-out test pattern in a resist pattern 17 subjected to lithography in the above manner is inclined, the pattern part 13 for managing dimension is observed from the rectangular pattern part 14 side, and a resist pattern section 15 is exposed to a substrate surface 16 and inspected. Thereby the sectional shape of the resist pattern can be highly precisely inspected without breaking the substrate.

Icp etching of tungsten for x-ray masks

Abstract: In this article the effects of process parameters of inductively coupled plasma etching with //Ar mixture gas and mask materials on the etched profile of W were investigated. While the etched profile was improved by -addition, low working presure, and reduced flow rate, the etching selectity (W against SAL resist) was decreased. Due to the difficulty of W etching with single layer resist, sputter deposited film was used as a hardmask. Reduction of required EB resist thickness through mask application could reduce proximity effect during e-beam patterning, but the etch anisotropy was degraded by decreased sidewall passiviation effect.

Lateral spreads of energy dissipation profiles of 20-kV electrons in polymethylmethacrylate: Functional representation and its application to proximity effect

Abstract: Monte Carlo calculations have been used extensively to study the energy dissipation of electrons penetrating into solid materials both in the direction of the initial electron trajectory and lateral to it. Knowing the lateral energy dissipation is important for the prediction of proximity effects in electron‐beam lithography and limiting resolution in scanning electron microscopy. The Weibull probability density functions are shown to approximate the lateral energy dissipation profiles determined by Monte Carlo calculations of 20‐keV electrons in polymethylmethacrylate (PMMA), and their application to simple line and square patterns of electron‐beam exposure are also discussed.

Method for reducing fogging effect

Abstract: PROBLEM TO BE SOLVED: To provide a method for correcting reliability of the irradiation parameters in an electron beam lithography system by taking the impact of fogging effect into account. SOLUTION: In the method for reducing the fogging effect in an electron beam lithography system, exposure is controlled in order to obtain a pattern matched to design data after processing. A model for fogging effect is fitted by varying at least the basic input parameters of a control function. The function type is selected depending on a kernel type being used in a proximity correction unit. Proximity effect is also taken into account, and an optimal set of parameters is obtained in order to get a common control function for proximity effect and fogging effect. Pattern writing by the electron beam lithography system is controlled by single proximity effect control function and fogging effect control function coupled in one data processing step using the same algorithm as that being executed in a standard proximity correction unit. COPYRIGHT: (C)2006,JPO&NCIPI