RU2415521C1 - X-ray beam image generator - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: in general case, proposed generator comprises source of exposing X-ray radiation, radiolucent shutter-interrupter to control exposing beam, coordinate table to support processed substrate and set of diaphragms to set light spot sizes. Proposed set of diaphragms is made up of two X-ray templates with radiolucent round or slit-shaped orifices with sizes made with preset spacing. Above design allows fast formation of topology of resistive mask in thick layer of X-ray resist to sub micrometer accuracy.

EFFECT: higher accuracy of formation of resistive mask topology using X-ray beam generator.

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Description

The present invention relates to X-ray lithography, and more specifically to a device for direct “drawing” of topological drawings by a spatially formed beam of exposure X-ray radiation - to an X-ray image generator. The device can be used in the technology of manufacturing X-ray templates for deep X-ray lithography, as a tool for forming a topological pattern in a thick layer of X-ray resist.

Selected as an analogue [described in: Bydin Yu.F., Vendik OG, Ivanov SA, Lesish Yu.K., Popov V.F. Electron-ionic methods of submicron technology. - Reviews on electronic technology. Series 3. Microelectronics. Issue 1 (1101), 1985, 40 pp.] The design of a raster-type electron beam image generator used to create a topological pattern on semiconductor and other substrates by direct drawing with a sharply focused electron beam. The device contains plates placed on the propagation path of the electron beam for interrupting the beam and lenses for focusing the beam, specifying the dimensions of its projection in the working plane, where the resist layer deposited on the surface of the processed substrate is located. During operation, such an image generator scans a “beam spot” over the entire surface of the processed substrate and the control system “turns it on” and “turns it off” in accordance with the program, the purpose of which is to form a topological pattern with a given geometry. The main and due to the algorithm of its operation, the disadvantage of image generators of this type are the relatively large exposure times of one substrate.

As a prototype selected [described in: B.G. Goldenberg, T. N. Goryachkovskaya, BC Eliseev, N. A. Kolchanov, V. I. Kondratiev, G. N. Kulipanov, V. M. Popik, S. E. Peltek, E.V. Petrova, V.F. Pindyurin. Production of LIGA templates for creating microfluidic analytical systems. - The surface. X-ray, synchrotron and neutron studies, 2008, No. 8, pp. 1-4] design of a vector-type X-ray image generator used to create LIGA patterns by direct dynamic X-ray lithography. The device contains a beam-chopper located on the path of X-ray propagation and a block of interchangeable diaphragms defining the projection of the exposure beam, with which a topological pattern is formed, in the working plane, where an X-ray resist layer deposited on the surface of the processed substrate is placed. The block consists of two slotted diaphragms, mutually perpendicularly arranged (in manual or automatic mode). In vector-type installations, unlike raster “ray spots”, not all points of the substrate are scanned, but move, shape and modulate it so that the exposure process is as time-efficient as possible, that is, the “spot” corresponding to the geometry moves only in those Substrate locations where exposure is required.

The disadvantage of the prototype is the insufficient (component of more than 10 micrometers) accuracy with which the apertures of the slotted diaphragms (the edges of which are the milling ground surfaces of metal plates) are installed, which leads to a decrease in the accuracy of formation of the topology of the resistive mask.

In order to increase the accuracy of forming the topology of the resistive mask using an X-ray image generator, it is proposed that its block of diaphragms be made in the form of two X-ray patterns containing sets of X-ray transparent holes of a slit shape made with a certain step in size to be moved in the plane of the orthogonal axis of the x-ray beam.

As a result of the implementation of the above proposals, the proposed device acquires the ability to form the aperture of the exposure beam with the accuracy specified by the step of manufacturing a set of x-ray transparent holes.

The following describes an example of the operation of the proposed device - x-ray image generator, the block of diaphragms which is made in the form of two x-ray templates containing sets of x-ray transparent holes of a slotted shape.

A typical x-ray image generator comprises an exposure x-ray source; operational opaque shutter-chopper for controlling a beam of exposure x-ray radiation; an automated block of diaphragms that sets the dimensions of the "light spot"; coordinate table on which the processed substrate is located.

The x-ray exposure, propagating from the source, passes on its way a block of diaphragms located in close proximity (to reduce diffraction effects) from the treated substrate. The drawing schematically illustrates the principle of operation of the block diaphragms. The diaphragm block contains two X-ray patterns (pos. 2 and 3) that are precision movable in the plane of the orthogonal axis of the x-ray beam (pos. 1), which include sets of x-ray transparent holes of a slotted shape made with a certain step in size, for example, with step 0, 5 microns. Each of the patterns defines the aperture of the exposure beam in its coordinate. The beam aperture during their sequential passage becomes (in the corresponding coordinate) with a certain accuracy equal to the size of the slit holes that are currently installed on its route (item 4). Propagating further, the beam of the exposure radiation falls on a certain section of the X-ray resistive layer deposited on the working surface of the processed substrate, set in accordance with the program for drawing the topological drawing using the coordinate table of the substrate, and exposes this section. Further, the process continues according to the program: either the beam of a given size is continued to be drawn, or the “light spot” is rebuilt to another size by installing the image of other slit holes on the x-ray templates on the center line of the X-ray generator. Depending on the sensitivity of the resist and the tuning time, it can be performed both with the closure of the operational X-ray opaque shutter-interrupter that impedes the propagation of the exposure x-ray beam, or without it.

In those cases when the topological pattern formed in the resist includes elements in the form of a circle, they can be drawn using a special X-ray pattern diaphragm block, which contains a set of circular transparent X-ray holes made with a certain step in size, by setting the hole the right size on the axis of the beam.

Claims (1)

X-ray image generator for use in the technology of manufacturing X-ray templates for deep X-ray lithography, as a tool for forming a topological pattern in a thick X-ray resist layer, containing a block of diaphragms, forming a beam of exposure X-ray radiation incident on the processed substrate, characterized in that the block of diaphragms is made in the form of moving apertures in the plane orthogonal to the x-ray beam, two x-ray patterns containing x-ray transparent sets x slotted holes made with a certain step in their size.