Institute For Physics Of Microstructures Research Articles

Maskless X-Ray Lithography Based on Microoptical Electromechanical Systems and Microfocus X-Ray Tubes

The main advantages and problems of maskless X-ray lithography (MXRL) are discussed. Consideration is given to two concepts of lithography in which the chip of a microoptical electromechanical system (MOEMS) of micromirrors and a microfocus X-ray tube chip with a “breakthrough” thin-film target are used as dynamic masks. Each of them can occupy its own niche in a research area or in the mass production of microchips. A description of the project of a MXRL facility (demonstrator of technologies), which is based on the concept of MOEMS, developed at the Institute for Physics of Microstructures, Russian Academy of Sciences, is presented for the first time.

Current status and development prospects for multilayer X-ray optics at the Institute for Physics of Microstructures, Russian Academy of Sciences

A real opportunity for applying traditional optical methods to soft X-ray and extreme UV (ultraviolet) radiation bands has appeared thanks to recent successes in the area of multilayer-mirror deposition and procedures for fabricating supersmooth and highly precise substrates of mirrors. The implementation of this opportunity opens up fundamentally new prospectss in the nanodiagnostics of substances, micro- and nanoelectronics, microbiology, solar astronomy and other applications. The main directions in multilayer X-ray optics developed at the Institute for the Physics of Microstructures, Russian Academy of Sciences, are presented and the aspects of the use thereof in science and technology are considered. The main problems arising during the fabrication of multilayer interference structures for the soft X-ray and extreme UV bands are discussed. The main results obtained recently in the scope of each direction of investigation are presented. Plans for the future development of these directions are discussed.

Comparative characteristics of optical methods for measuring the surface shape at the institute for physics of microstructures, Russian Academy of Sciences

Several optical methods for measuring the shape of a mirror surface are presented. Their advantages, disadvantages, and fields of applications are indicated. The results of measurements conducted for the same spherical mirror with the use of these methods are given. Good agreement between the results is obtained.

Precision imaging multilayer optics for soft X-rays and extreme ultraviolet bands

Optical methods that provide high diffraction image quality with a spatial resolution of several to tens of nanometers and are in demand in such areas as projection lithography, X-ray microscopy, astrophysics, and fundamental research on the interaction of matter (vacuum) with ultrahigh (– W cm) electromagnetic fields are reviewed in terms of fabrication and testing technologies and possible use in the – nm wavelength range. The current worldwide status of and recent achievements by the Institute for Physics of Microstructures of the Russian Academy of Sciences (RAS) in the field are discussed.

Reflective mask for projection lithography operating at a wavelength of 13.5 nm

This work is devoted to the technology of mask manufacturing and investigation of the characteristics of the reflective mask employed in the extreme ultraviolet lithography test bench designed at the Institute for Physics of Microstructures, Russian Academy of Sciences. The mask’s structure and composition have been optimized. The antireflecting (absorbing) coating and stop-layer materials that are used to etch the mask structure and the multilayer interference system, which reflects radiation at the operating wavelength, have been selected. The mask manufacturing technology is described. The measured reflective and geometrical characteristics of a mask (absorbing layer thicknesses, line widths, and line-edge roughnesses) are presented. A new direct method for certifying mask defects of 30 nm or more is proposed.

Bandpass microwave filters based on YBCO high-temperature superconductor films

The experimental characteristics and results of a simulation of four-pole filters based on high-temperature superconductor films fabricated by the Theva firm (Munich) and the Institute for Physics of Microstructures, Russian Academy of Sciences (Nizhnii Novgorod) are presented. The model parameters and surface resistance of the investigated films are determined from the characteristics obtained. For direct measurements of the films’ surface resistance, a disc resonator with a frequency of 10 GHz has been developed at the Institute for Physics of Microstructures.

Diffraction-limited short-wavelength optics: Analysis, fabrication, and application

The fundamental physical and technological problems of fabrication and testing, as well as new optics applications providing diffraction-quality images (with spatial resolutions varying from tens of nanometers to several nanometers) at wavelengths of 3–60 nm, are analyzed. This type of optical systems is required in the mass production of very large-scale integrated circuits (ICs) (projection nanolithography), nanocertification (high-resolution X-ray microscopy), macrodiagnosis (extraterrestrial astronomy), and in fundamental investigations of the interaction between a material (vacuum) and superstrong electromagnetic fields (1020−1023 W/cm2). The current state of interaction studies around the world has been reviewed. The latest developments implemented in this area at the Institute for Physics of Microstructures, Russian Academy of Sciences, have been discussed.

Features of technology of high-temperature superconductor films for microwave filters

The characteristics of fourth-order bandpass microwave filters based on high-temperature super-conductor (HTS) films have been numerically simulated and experimentally measured for the devices based on YBCO films purchased from Theva GmbH (Munich) and manufactured at the Institute for Physics of Microstructures (Nizhni Novgorod). Experimental data were used to determine the parameters of the surface impedance model for the HTS films. The results show that HTS-based filters with high performance characteristics can be obtained using HTS films manufactured by different technologies.

A stand for a projection EUV nanolithographer-multiplicator with a design resolution of 30 nm

An original stand for a nanolithographer-multiplicator with an operating wavelength of 13.5 nm and a design spatial resolution of 30 nm has been developed in Russia at the Institute for Physics of Microstructures, Russian Academy of Sciences. A detailed description of basic principles and approaches used when constructing the stand and its key elements is given. The experiments planned to be performed using the stand are discussed.

On creating multilayer X-ray focusing mirrors

We review the recent studies and results obtained in the last five years at the Institute for Physics of Microstructures (IPM) in the field of multilayer mirror construction for hard X-ray wavelength range ( 7n = 0.05—0.25 nm), E = 25—5 keV)). Mirrors with cylindrical and spheroidal shapes as well as Kirkpatrick-Baez cross systems are considered.

Activity in manufacturing and characterization of X-ray optical elements and ultrahigh-resolution systems at IPM RAS

The latest developments in the field of metrology and correction of high-ratio substrates for X-ray optics with a subnanometer scale accuracy, carried out at the Institute for Physics of Microstructures (IPM), Russian Academy of Sciences, are reported. A scheme of an interferometer with a diffracted reference wave, based on a single-mode fiber with a narrowed exit aperture, is reported. Some methods for shape correction are described.

Testing and correction of optical elements with subnanometer precision

The paper is devoted to the fundamental physical and technological problems of manufacturing and testing high-precision optical elements and wave fronts of complex optical systems with subnanometer accuracy. The features of using a point diffraction interferometer (PDI) for measurements of high-numerical-aperture (NA ∼ 0.3) optics with generally aspherical surfaces are considered. A new type of PDI reference sphericalwave source used in the interferometer of the Institute for Physics of Microstructures (IPM) is described. The main technical characteristics of the IPM interferometer and the interferometer at the ALS synchrotron (United States) are compared. Some schemes of using the spherical reference wave interferometer for studying aspherical surfaces and their applications for testing the aspherical mirrors of a nanolithographic objective with an operating wavelength of 13.5 nm are considered. The techniques developed at the Institute for Physics of Microstructures for high-precision surface-shape correction are described, and the corresponding results are reported.

Shortwave projection nanolithography

The article below is dedicated to research into nanolithography in the ultrashort spectral region that was conducted at the RAS Institute for Physics of Microstructures and discussed at an RAS Presidium meeting. These findings, according to the participants in the meeting, can actually be used to revive the Russian microelectronic industry.