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Experimental results on a stencil mask picture (size 0.1 ωm) are presented which transfer by electron beam into a positive resistance layer (thickness 0.3–1.5 μm). The dependence of pattern profile vs electron energy and radiation dose is investigated. The technology of stencil mask fabrication for electron, ion and X-ray lithography is proposed. The mask pattern multiplication system and the system of image registration for a stencil mask-substrate are also discussed.

Experimental and mathematical modeling methods were used in an investigation of the influence of the degree of coherence at the entry to an optical projection system on the quality of the resultant images. It is shown that laser projection lithography is possible in a system with a nonscanning K?hler-type fly's eye illuminator and an excimer laser as the light source.

The coherence properties of light sources used in the projection lithographic systems strongly affect the photomask image quality reproduced on semiconductor wafer, because they determine the minimum resolvable feature size and the level of speckle in the image. The spatial coherence of excimer laser radiation is measured. A simple relation between the coherence of the excimer laser radiation and its divergency is presented. The dependence of excimer laser coherence on the width of intracavity apertures and the pulse duration is shown. The influence of the spatial coherence on the image quality in the projection system equipped with fly's eye element is considered. The optimization procedure of the radiation parameters and the fly's eye illuminator is described.

An investigation was made of the spatial coherence of excimer lasers in different resonator geometries. Lasing with a spectral width of 5 nm was obtained in a scheme using a grating in the autocollimation regime and a four-prism telescope. A discussion is given of the questions involved in employing excimer lasers having a narrow laser emission line in photolithographic projection systems.

In present time six types of siliconorganic materials are commonly used in microelectronic, technology: polysiloxanes, polysilozanes, polysilmethylenes, polysilphenylenes, organic polymers with silicon getheroathorns and polysilanes [1].

A new resist composition based on PMMA-MAA copolymer with antracene additive was exposed by a single pulse of KrFexcimer laser (X =248 nm). Its contrast was found to exceed significantly the limitdetermined by light absorbtion. Studies of the development kinetics of the resist and correspondingtheoretical reasoning justify the assumption of a thermal activated process (boiling of the residual dissolver).1. INTRODUCTION Recently, a new positive UV-photoresist for pulsed excimer laser exposure at X =193 and 248 nm has been reported1. The new resist composition is based on a PMMA-MAA copolymer dissolved 1:9 inethylcellosolveacetate (ECA) with an additive of 1 to 7% of antracene. The contrast ' and the sensitivity D of the new resist were found to be strongly dependent on the mode of exposure. These parameters were relatively poor (D >0.5 J/cm2, '

The technology of x-ray W-Al multilayer mirrors with an angular reflection width of more than 0.4 degrees at a 1.54-A wavelength is developed. On this basis an x-ray scanner is constructed. We show experimentally the possibility of object-transfer imaging with a resolution of ~20 mum.

In this report the experimental results of the resist silylation and O2‐plasma development are presented. The Soviet commercial novolac based photoresists of both positive and negative type and gas phase silylation in hexamethyldisilazane (HMDS) were used. The flood exposure of the resist films was made by Hg lamp or KrF laser. It is found that the silylated resist film mass growth (per resist surface square) must exceed 15×10−6 g/cm2 to provide the formation of the etching barrier layer under O2‐plasma development. The silylation kinetic is shown to be linear at first period. The dependence of the initial silylation rate on the experimental conditions was studied and results are discussed. Under the silylation of the highly crosslinked resist films the induction effect was observed. For both positive and negative processes the silylation conditions providing selective O2‐plasma development are determined. To enhance the contrast of O2‐plasma development the three‐stage procedure was elaborated.

A Michaelson interferometer was used in determination of longitudinal and transverse correlation functions of the radiation field of an XeCl laser. The coherence of the radiation emitted by this excimer laser was investigated. The coherence lengths, radii, and coefficients were determined. The coherence radii were found to be different for different directions across the aperture of the laser beam. The role of coherence of the radiation in the applications of excimer lasers in projection photolithography was analyzed.

The characteristic features of the use of pulsed ultraviolet lasers in photolithography were studied, including the high pulse power and monochromaticity of laser radiation. An experimental study was made of the photolithographic process carried out using a pulsed nitrogen laser emitting at λ = 337 nm. Structures of (1.2–1.3)λ size were formed in FP-617 photoresist.

The exposure of positive photoresists like AZ-2400 and AZ-2415 with pulsed excimer XeCl laser (λ= 308 nm) results in a thresholdlike growth of sensitivity and contrast of the resists [1]. The effect appears when pulse energy density W is in interval 3.106 - 5.106W/cm2, which is little lower than the ablation threshold of the resists - W = 5.10 W/cm2. We called exposure in this interval of W as preablation mode of exposure.© (1987) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The spatial coherence of the excimer laser radiation seriously affects the quality of the images being reproduced by diffraction limited optics in photolithography. It is shown that the coherence parameters of excimer laser radiation exceed the necessary level in 102–103 times. To decrease the coherence down to the optimal level a fly’s eye element is used. The concept of Kirchhoff integrals has been applied to calculate the mutual intensity function transformation by the illuminator of the projection system equipped with fly’s eye element.

Results of photolithography experiments utilizing the XeCl excimer laser and positive photoresists are reported. Abrupt reciprocity loss resulting in the growth of photoresist contrast and sensitivity was found when laser pulse energy density exceeded a threshold value of about 50 mJ/cm2. Percolation theory is used to derive a model of resist thickness remaining versus dose for development of pulse exposed photoresist. The model accurately describes the change in dissolution of AZ2400 photoresist when the energy is delivered in multiple versus single pulse exposures.