SU481145A1 - Device for projection printing and registration of photomask patterns with substrate - Google Patents

Description

The invention relates to the field of the technology of manufacturing integrated circuits and semiconductor devices, in particular, to automatic projection photolithography devices — photo repeaters, photo-type devices and installations — projection matching and exposure for making photo masks and engraving masking micro-reliefs on the surface of semiconductor substrates by photo photographic methods.

Devices are known for projection printing and combining patterns of photomasks with a substrate, which contain an optical projection system, a three-channel photoelectric microscope. an electronic measuring unit, an exposure unit, a tracking system of relative orientation and movement of the substrate and photo gage, and a reading two-coordinate unit.

A disadvantage of the known devices is that the photoelectric tracking systems, due to the mutual masking of the reference signs of alignment in their local representation, and "dead zones" in their discriminatory characteristics, which leads to a decrease in their field of view, disruption of mutual monitoring. the position of the combined reference marks and the decrease in the accuracy of the base and alignment of the photogamelace with the substrate.

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To expand the field of view of the photoelectric tracking system and increase the accuracy of combining, the proposed device is equipped with autonomous light sources located behind the photo plate that serve to illuminate the surface of the substrate, and each optical channel of the photoelectric microscope is also equipped with independent light sources for illuminating the photo plate sections, and the aforementioned light sources through power supply and power amplifiers are connected to separate units comparing the amplitudes of the signals from the rep image Black marks of the substrate and the photo.

FIG. Figure 1 shows the optical layout of the described projection printing device and a block diagram of its photoelectric tracking system; in fig. 2 - diagrams of output pulse signals of a photoelectric microscope.

A device for projection printing of a photographic substrate 1 onto a substrate 2 comprises a projection lens 3, coordinate tables with a micromanipulator 4 for orientation and movement of the plate during image multiplication on its surface using a follower-controlled photoelectric microscope (FEM) signals, which consists of logic block 5 controls not

complementary engines 6 for micromanipto torus II xorodat tables, the unregistration of which is registered by the county dvuhkoorshim iklokom 7. The device contains also trico ordinates kjjiii croji and for izirovi ryf the image of the image), and i ay ayr ayr ayr ayr a ı а аr а а а а а а а а а а а а а а а а а іr а а а аn а аn а іn а ı аr а а а а а а а а а а а а а а а 3); US, K11 Koropoio is performed by DIHI / SLI; but with: ia, new block l or oisratirol, ipCAi c.iiu.:buy;o with a system to illuminate reamer signs lU alignment i the substrate 2, each channel of which is supported by light bctoiiuhv light il, condenser i, solr /. c on the figures q: l COST of the LILIA 1, field apertures 13, behind which there are three channels of channels ii, projecting together with condensate i2 of the light source of the light sources 11 into the pupil of the active component 3, and the luRozer is a case of the designer, and the lu-rus r ove r i r o c o The first stage of Photochabel 1 is an extensional unit consisting of an ID condenser and a light source 17, as well as a three-channel Foch-.1, each channel of which consists of a unit of the module (6, team IV, field diaphragms: 2.. Bccfc FEM unite 11Y . ooschim length AKH scanning disc with an Lpji pyiouj, ii: 4n radiaLo11V1Mk scheleBbiMii phrenic 2 ;, for which three usganovlepv fotoir11eylp; Single 26 elektrnchesk -1e kotorve output signals; x usilizayuts amplifiers 2h: n further enter the device elektroiiv1e nzmerntslpv1e 2 about each channel FEL1. Output information from these measuring devices it is processed by a private unit 6, which controls the tracking system of the automatic base and combines the photomask and the substrate. 1 Each photoelectric channel of the PV: 1 is equipped with an independent lighting device to illuminate the sections of the photo stack of 1 with the reference signs 26 the combined 1) I, i- The ioTopoe consists of a light source 27, a coidecore 2 and a semi-cut mirror 29. The device contains a block for adjusting the amplitudes of signals from images of hHppHBix alignment marks on a photo pattern on a semiconductor substrate during of this technological cycle of the manufacture of devices i: a of the surface of the slide, it consists in each channel of the Felch from block 30 injected signals from the picker} of the sign of the 26 sign combined on (rotoschable 1, block 31 for the disconnection of the signal from the reprinted sign of 10 substrate 2, integrators (peak detectors) 32 and 33, comparison units 34 n 35 aggplits indicated signals: OB with support at multi-levels UQ and, with power sources 36 and 37, signals from the input come to power sources 38 and 39 , OILNZIROVSIN code so me: l. to 1 and the illumination field channel of the device for printing a printing device, its operation of the device of the system and the blocking of photoelectric stabilization of the amplitudes of sigals from images of repellent signs; In the process of combining, the rendered signs of the 10 alignment, performed on the substrate in the form of single or double 1 st marks, are illuminated by ns junior scores II and their obstruction mirrored by the comfort of flat-foschsabloya i, and the distunted mirrors were replaced by a distunted mirrored shapes on the surface of the distant shapes. penepHBix marks 26 of photomask 1, BBIs filled in with internal strokes and illuminated with light sources 27 FEM, are projected in each channel of the ICI lenses into the illumination of the aperture 20, and in this plane the image is scanned with the slit analog The rotating diaphragms 22 of the rotating 21. From the input of the photoreceivers 23 of each channel of the FEM follow the signals (Fig. 2). representing in time the distribution of illumination in the joint image combines the rendered signs of the photomask and the substrate, as they shift relative to each other (olig. 2a), so iri; 1 mutual fixation (Fig. 26, 2c). In this case, the signals 40 follow from the image of the optical diaphragms 20, the signals from 41 and 42, respectively, from the alignments of the reversed stroke marks and the photo mask. Mutual arrangement of repetitive signs in the field of view of the FEM is determined by the appropriate time to reliably segregate sigals from the indicated signs on the form of dyscreens (characteristics) of the characteristics of each channel of the following system, you need to go to the program, you will need to go to the program, you will need to go to the program, you will need to go to the phone, you will need to go to the phone), the program will have to go to the program, then you will need to go to the program, you will need to go to the program, you will need to go to the system, you will need to go to the program, you will have to go to the program, you will need to go to) lay above the level 43 of the signal determined by the reflection coefficient of the mirror surface of the substrate and the signal 42 from the image of the renal sign 26 of the photomask 1 must lie at the level 43. The violation of this Conditions, when working with a metallized (coated with aluminum film) substrate, when the signal 42 (Fig. 26) from the image of the renalized substrate substrate lies above level 43, excludes its separation from the common signal of intermittent repetitive signs and this in its turn but This is one of the “dead zoiv’s discriminatory characteristics of the photovoltaic system. The fulfillment of this condition, i.e. the bleaching of the necessary photometric contrast, combining the red signs for different values of the reflection coefficients ioverh1 yustey audio-on-1 kotopBix ONL arranged in ustro; 1stve provided a system of automatic control of the amplitudes of signals from an image reperpyh characters which controls the level osveN ennostn fiducials (}) N otoshablona

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substrate using autonomous light sources.

Block the pulse signals 41 are drawn from the image of the reference mark of the pollozhki above the level 43, and the block 31 separates the signals 42 from the image of the reference mark 26 of the photomask 1 lying 43. The integrators 32 and 33 measure the amplitude of these signals, the blocks 34 and 35 compare them with the established G7o levels and, and the error signals from these blocks through power amplifiers 36 and 37, arrive at the control of the inputs of the stabilized power supplies 38 and 39, changing the intensity of the light sources And and 27 in the corresponding LEM and illuminator channels floor conductor plate, thereby varying illuminance is fiducials so that the amplitude and, tt Us signals 41 and 42 remain constant and equal to the set UROVT1YAM.

Such a system of automatic adjustment of the photometric contrast of the reference marks of the photomask and the substrate in their joint image makes it possible to reliably record these signs throughout the entire field of view of the FEM during the entire technological cycle from the construction of devices on the semiconductor

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substrate, its integral coefficient of reflection varies in n Spropels m.lR-n.85V

Subject invention

DEVICE d.-t projection p.ch tp and combining FIGURES of the stabilizer with the substrate containing the optical projection system. three-channel Lotoedextry horizontal microscope with electronic measuring unit, display unit. It is a matter of a mutual syllable of 1NOCH that focuses on the whispering of the substrate and the display and the readout of the two-coordinate system, which differs from the tel. what. in order to expand the field of view of the odoedektri eskoczd syshey sistelta tt ttvttn i r o r o ry j o r o ry j o r o r o r h o r o r o r h o r o r o r o h o r o r o r o r h o r o h o r o r o h o r o l o r o l o r o l o r o l o r o l o r o l o r o l o r o l o r o r h o r o h o r o ект s h-l o r ı h источ l o источ t a s света t h ц t t. t. s. источ источ , dd of illumination of Lotoit Bond sites, and the aforementioned lights, through power sources and power amplifiers, are connected to separate units for comparing the amplitudes of signals from the image of reference marks of a spoon and (b then: iablona.

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