SU966655A1 - Versions of photolythography - Google Patents

Description

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The invention relates to micro and optoelectronics and can be used with a planar technology of transferring the topology of electronic, optical and optoelectronic circuits.

The known method of photolithography includes the exposure of a substrate with a photosensitive layer of actinic radiation through a set of matching photo masks. with different total areas of masking coatings 1.

A disadvantage of the known photolithography method is the different heating of dark-field (80-95% floor) by 2-4 ° C and light-field photo-masks (5-20% floor) by 0, 8 ° C, due to which when using large photo-templates (103 x 103 x X 127 mM) absolute linear displacement of peripheral elements with preliminary alignment of the marks 2.2-4.3 and 0.2-0.6 µm, respectively, while the combination accuracy should be 0.3-0.5 µm.

The closest to the proposed method is photolithography, which involves exposing a substrate with a photosensitive layer to actinic radiation through a set of matching photo masks with different total masking coverage areas and heating the substrate. The substrate is heated to a temperature determined from a formula that takes into account the change in the linear dimensions of the images of photomasks during exposure, as compared with the original, and the need to correct them 2.

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The disadvantage of this method is low productivity of the lithographic process, due to the large time costs due to the need before each exposure, to avoid care

15 pixel sizes, measurements of the initial, and then the establishment, measurement and maintenance (temperature control) of the temperature calculated by the formula, which increases sharply during exposure. In this case, the formula provides only a linear size correction, whereas, depending on the geometry of the general arrangement of the maxiating layer on the template, there may be a barrel or pincushion-like deformation in the plane. The purpose of the invention is to increase the productivity of the process and increase the yield of usable products by eliminating care of the sizes of elements. The goal is achieved by the fact that according to the photolithography method, including exposing a substrate with a photosensitive layer to actinic radiation and cutting a set of matching photo masks with different areas of masking coatings and heating the substrate, heating under the photosensitive layer is carried out during the pattern by applying a layer to the substrate. radiation at intervals of wavelengths, the absorption coefficients of which for the used L1 skimming coating are inversely proportional the total area of absorbing elements of the corresponding photomasks. . According to the second variant, the heating of the substrate with the photosensitive layer is carried out in the process of exposure by selecting the material;

Catching coverings with the total areas of absorbing elements of the respective photo masks, are proportional to the coefficient of absorption of the ground wavelength of the exposure radiation of FIG. 1-3, a diagram of a complex of three matching photomasks with the area ratio of the absorbing elements IS: 2S: 3S and masking coverings of C, Hell and A in FIG. 4-6 is a diagram of a set of three matching photo masks with a ratio of the total areas of absorbing elements IS: 2S: 3s and masking with silver coatings (or FejPs); in fig. 7 graphs of the dependence of the absorption coefficients of various materials on the wavelength Example. The ratio of the total areas of absorbing elements of the photo template kit (Fig. 1-3) IS: 2S:: 3S. Cu, Hell, Af, respectively, were chosen as masking coatings. Exposure is performed by actinized radiation with a dA of 335-345. nm. As can be seen from the graphs (Fig. 7), for the range of wavelengths l X 335-345 nm, the ratio of the absorption coefficients is Cu: Hell: AR 3: 2: which ensures that the dimensions of the elements obtained using this set of LSI and VLSI photo patterns are eliminated various thermal expansion of photomasks with different total

Claims (2)

optical elements and elements of LSI and VLSI due to the unequal thermal expansion of photo patterns with different total areas of absorbing elements 4 areas of absorbing elements under the action of aKjHHH4Horo radiation. Example 2. The total areas of absorbing elements of the photomask kit (Fig. 4-6) with a masking silver coating (or FejOj, d 0.25 µm) are determined using a two-beam spectrophotometer of the Specord uv vis type in the region of 550-650 nm. The ratio of these areas is 1S: 2S: 3S. The ratio of silver absorption coefficients (FejOs) (Fig. 7) for the wavelength intervals 333-337, 340345 and 370-380 nm (350-360, 420-430 and 450-460 nm) is 3: 2: 1. A set of interchangeable interference filters at selected wavelength intervals are inserted into the exposure system. In this way, due to the same total absorption of actinic radiation during exposure, the size of matching photomasks with different 1mN areas of masking coatings and, accordingly, the resulting circuits are avoided. The proposed versions of the photolithography method makes it possible to exclude the departure of dimensions under the action of actinic radiation, provide an absolute combination of the topology of the schemes obtained, they are easy to use and speed up the process of manufacturing an LSI and VLSI 15-20 times. Claim 1. Photolithography method, which includes exposing a substrate with a photosensitive layer of actinic radiation through a set of matching photo-patterns with different areas of the elements of masking coatings and heating the substrate, so that to improve the performance of the process and increase yield of products by - eliminating the departure of the dimensions of the elements, the heating of the substrate with the photosensitive layer is carried out in the process of exposure by exposure to it Niemi in wavelength ranges, absorption coefficients are used for masking coatings are inversely proportional to the total area of the absorbent m zlementy respective photomasks. 2. A method of photolithography, including exposing a substrate with a photosensitive layer of actinic radiation through I set of matching photo masks with different areas of masking coating elements and substrate heating, characterized in that, in order to increase the performance of the process and increase the yield of useful products by eliminating care the dimensions of the elements, the heating of the substrate with a photosensitive layer is carried out in the process of exposure by selecting the first materials of masking coatings with total areas of 4 elements of the respective photo slabs, which are proportional to the absorption coefficients of the wavelength range of the exposure radiation. , Sources of information taken in our opinion 1. Expert introduction to photolithography. Ed. . V.P. Lavrishcheva, M., Energie, 1977, p. 205300. 2. USSR author's certificate №577506, cl. G 03 F 7/20, 1977 (prototype). si FIG. / BUT T / In //// 7 // 7 /: i f .one Al     f f f f fMJLffffff f f Fig.Z A3 (feM    . s j X FIG. five Ag (fetQ3J S SSSS S S S SSSSS f 0ttt.6 "/ 9 / tH9hlOytOl /