JPH01155347A - Exposing device - Google Patents

Abstract

PURPOSE:To obtain an exposing device which does not need an operation for adjusting masks and also obtains high yield by using a transmission type plane display, which draws a displayed image as a mask pattern, as a mask pattern transfer device. CONSTITUTION:The transmission type liquid crystal display 10 which is a matrix driving type is disposed on an optical path between a condenser lens 3 and a reduction projecting system lens 6 disposed in a reduction projecting exposing device main body 1. And pattern data is accumulated in the memory in a controller 11 and the pattern data on a first mask is transmitted to the transmission type liquid crystal display 10 from the controller 11 through an interface line 12, so that a first mask pattern is drawn on the transmission type liquid crystal display 10 according to the principle of the action of an active matrix driving liquid crystal display. By radiating light beams from a light source 2 in such a state, the first pattern is printed on a wafer 8 with the pattern on the transmission type liquid crystal display 10 as a mask.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a mask pattern applied to the formation of thin film integrated circuits including semiconductor integrated circuits, printed wiring boards of electronic circuits, etc. The present invention relates to an exposure device that transfers images onto a substrate.

[Conventional technology]

In general, (1) film deposition technology is used to form printed wiring boards for thin film integrated circuits and electronic circuits such as semiconductor integrated circuits, optical integrated circuits, and thin film transistor integrated circuits.

Three technologies are essential: (2) mask pattern transfer technology and (3) etching technology to remove unnecessary parts of the film.
These techniques are used repeatedly to produce desired thin film integrated circuits and the like.

The film deposition technology of (1) is S1 wafer, GaAs wafer.

This is a technique for uniformly depositing films of various materials on flat substrates such as glass substrates, ceramic substrates, and glass epoxy substrates. In addition, the mask pattern transfer technology (2) uniformly coats a deposited flat film with a resist that is sensitive to light (including not only visible light but also ultraviolet light and deep ultraviolet light), and then draws a pattern with a click. This is a technique in which a desired pattern is printed onto the resist by shining light onto it through a photomask made of quartz glass or the like. The etching technique (3) is a technique for removing unnecessary portions while leaving a desired batten film after transferring a mask pattern. The present invention is based on (2) of the above three techniques.
The present invention relates to an exposure apparatus applied to mask pattern transfer technology.

Conventional mask pattern transfer devices include a full-size projection exposure device that prints a pattern of the same size as the mask pattern onto the substrate, a contact exposure device that brings the photomask and substrate into close contact, and a mask pattern transfer device that prints a pattern with the same size as the mask pattern on the substrate. There are reduction projection exposure apparatuses that reduce and project a pattern to 1710, etc., and divisional exposure apparatuses that divide and expose a pattern to print a pattern over a large area. Both devices use a photomask on which a desired pattern is drawn using an electron beam or the like on a transparent substrate such as quartz glass. Light is exposed to the substrate coated with resist through this photomask, and the mask pattern is transferred. Is going.

FIG. 5 is a sectional view showing the configuration of a reduction projection exposure apparatus most commonly used in the manufacture of semiconductor integrated circuits.

In the figure, light from a light source 2 disposed at the upper part of the reduction projection exposure apparatus main body 1 is transmitted through a condenser lens 3. Photomask 4. It passes sequentially through the photomask holder 5 and the reduction projection system lens 6 and reaches the sea urchin 8 on the XY stage T.

9 is the optical path of light.

Normally, the manufacturing of semiconductor integrated circuits requires several to ten or more photomasks, and the photomasks 4 are replaced and replaced one after another.
It is necessary to install it. This photomask installation operation is performed in the following steps.

First, the photomask 4 is fixed to the photomask holder 5 while maintaining a predetermined dimensional accuracy. Next, the photomask holder 5 to which the photomask 4 is fixed is aligned with the reduction projection exposure apparatus main body 1 with a predetermined accuracy and fixedly installed. Depending on the type of reduction projection exposure apparatus, there are those in which the photomask holder 5 is not provided and the photomask 4 is directly installed in the apparatus main body 1.

[Problem that the invention seeks to solve]

In order to manufacture thin film integrated circuits such as semiconductor integrated circuits using conventional exposure equipment, it is necessary to use several to ten or more photomasks 4, each costing between 10,000 yen and several million yen, which is extremely uneconomical and expensive. Instead, it takes several days to several weeks to make photomask 4,
There was a problem in that even after manufacturing began, it took time to replace and install the photomask 4. Furthermore, if the photomask 4 is not placed within the desired accuracy, the positional relationship between the multiple masks may become inconvenient, resulting in the thin film integrated circuit not operating properly after manufacturing. There is also the problem that the installation accuracy of the photomask 4 affects the yield. Furthermore, since the mask must be replaced frequently, the photomask 4 cannot be installed in a sealed structure that does not allow dust to enter, and dust that falls on the photomask 4 may cause defects.
There is a problem in that the yield may be lowered.

The purpose of the present invention is to eliminate photomasks that are expensive, take a long time to manufacture, and require replacement and installation operations, and to provide an exposure apparatus that is economical, does not require mask alignment operations, and provides high yields. It is about providing.

[Means for solving problems]

The present invention uses a transmissive flat display instead of a photomask as a mask pattern transfer device.

[Effect]

In the present invention, a display image drawn on a transmissive flat display is used as a mask pattern, and the display image is transferred onto a substrate coated with resist.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of an exposure apparatus according to the present invention, and the same parts as in the previous figures are given the same reference numerals. In the figure, a matrix-driven transmissive liquid crystal display 10 is disposed on the optical path between a condenser lens 3 and a reduction projection system lens 6 disposed inside a reduction projection exposure apparatus main body 1, and further A control device 11 for driving the transmissive liquid crystal display 10 and transmitting drawing data is disposed outside the exposure apparatus main body 1, and the two are airtightly connected by an interface line 12. Furthermore, sealing plates 13 are provided around the condenser lens 3 and the transmissive liquid crystal display 10 disposed inside the exposure apparatus main body 1 to prevent dust from entering.

FIG. 2 is a sectional view showing the structure of the above-mentioned IJ drive type transmissive liquid crystal display 10. As shown in FIG.

In the figure, 20 is a TN liquid crystal layer, 21a and 21b are molecular alignment layers that twist and align the liquid crystal molecules in the TN liquid crystal layer 20, 22m and 22b are transparent electrodes, and 23 is a thin film transistor (TP) constituting an active matrix.
T) layer 24 & , 24b is a transparent glass substrate 25
is the peripheral sealing personnel for sealing the TN liquid crystal layer 20, 26m;
26b is a polarizing plate whose polarization directions are different from each other by 90 degrees.

In such a configuration, when an electric field is applied to the liquid crystal cell corresponding to each intersection of the matrix, the liquid crystal molecules are aligned with the direction of the electric field and perpendicular to the polarizing plates zsa, 26b, so that the liquid crystal molecules incident on the TN liquid crystal layer 20 are The light is blocked by the lower polarizing plate 26b and cannot pass through the liquid crystal display 10. On the other hand, in a liquid crystal cell to which no electric field is applied, the upper polarizing plate 26
The light that has passed through m travels along the alignment state of the liquid crystal molecules, is twisted by 90 degrees, reaches the lower polarizing plate 26b, and passes through the polarizing plate 26b for the tth time. That is, when no electric field is applied, light can pass through the liquid crystal cell.

Next, the operation shown in FIG. 1 will be explained using a semiconductor integrated circuit manufacturing process as an example. First, the button data for all the masks necessary for manufacturing the semiconductor integrated circuit is stored in the memory in the control device 11, and the button data for the first mask is sent from the control device 11 to the transmissive liquid crystal display via the interface line 12. 10, and a first mask pattern is drawn on the transmissive liquid crystal display 10 according to the operating principle of an active matrix liquid crystal display. In this state, light is irradiated from the light source 2 to print a first pattern on the sea urchin 8 using the pattern on the transmissive liquid crystal display 10 as a mask. In the case of mass production, projection exposure is repeated in the same manner while replacing the wafer 8. Thereafter, the wafer 8 to which the first mask pattern has been transferred is subjected to etching processing, film deposition processing, and cleaning processing, after which a resist is applied and the wafer 8 is again installed in the exposure apparatus as shown in the same figure. Thereafter, the same process as performed for the first photomask 4 is repeated for the second mask.

That is, the control device 11 sends the button data for the second mask to the transmissive liquid crystal display 10, draws the second mask pattern on the transmissive liquid crystal display 1θ, and draws this pattern again on the sea urchin 8. Burn it. The exposure process is repeated in the same manner until the last mask.

With this configuration, there is no need to actually manufacture photomasks, and no matter how many masks are needed, there is no need to replace or install masks. In addition, a common coordinate origin for each mask is determined on the transmissive liquid crystal display 10,
If all Ω masks are drawn based on this, each mask pattern can be drawn on the transmissive liquid crystal display 10 without causing mask displacement. Furthermore, since there is no need to replace masks, the transmissive liquid crystal display 10 can be enclosed in a sealed structure and protected from dust, thereby significantly improving yield.

FIG. 3 is a cross-sectional view of the structure of another embodiment of the exposure apparatus according to the present invention, and the same parts as in the previous figures are given the same reference numerals. The difference between this figure and FIG. 1 is that on the optical path between the condenser lens 3 and the reduction projection system lens 6,
A thermal writing phase change type transmissive liquid crystal display 14 and a half mirror 15 are provided, and the half mirror 15
A slam writing mechanism 16 is disposed opposite to. Also, a thermal writing control device 1 is provided outside the exposure apparatus main body 1.
7 and a button erase circuit 18 are provided, each of which is electrically connected to the interface M12.

FIG. 4 is a cross-sectional structural diagram of the thermal writing phase change type transmission type liquid crystal display 14 described above. In the figure, 30 is a liquid crystal layer 31m in which smethic liquid crystals or cholesteric liquid crystals are regularly arranged.

31b is a transparent electrode, and 32m and 32b are transparent glass substrates.

In such a configuration, the display principle of the thermal writing phase change type liquid crystal display is that when the liquid crystal molecules in the liquid crystal layer 30 are in a regular arrangement state, the input light 33 is transmitted through the liquid crystal layer 30 and is projected as projection light 34. However, the input light 33 cannot pass through the liquid crystal layer 30 because the input light 33 is not transmitted through the liquid crystal layer 30 because it is irradiated with the laser beam 35 and the alignment of the liquid crystal molecules is disturbed. Based on this principle, a mask pattern can be drawn on the liquid crystal layer 30 by irradiation scanning with the laser beam 35. Also,
By applying an alternating current voltage between the transparent electrodes 31m and 31b, the drawn image can be erased and the liquid crystal layer 30 can be returned to its original regularly arranged state.

Next, the operation of the exposure apparatus according to the present invention shown in FIG. 3 will be explained using the semiconductor integrated circuit process as an example, similar to FIG. 1. First, the thermal writing control device 17 transfers pattern data for all masks necessary for manufacturing the semiconductor integrated circuit.
and sends the first mask's baton data to the baton writing mechanism 16. The button writing mechanism 16 performs irradiation scanning with the laser beam 35 according to the button data, and while the laser beam 35 is reflected by the bar 7mi 9-15, the first image is written on the thermal writing phase change transmissive liquid crystal display 14. Draw a mask pattern. In this state, light is irradiated from the light source 2, and the transmissive liquid crystal display 1 is
The pattern on 4 is transferred onto wafer 8. For mass production,
Repeat the projection exposure in the same manner while replacing 8 with the sea urchin. Thereafter, after performing various processes on the sea urchin to which the first mask pattern has been transferred, it is placed in the main exposure apparatus again, and a command is issued from the thermal writing control device 17 to the pattern erasing circuit 18.
The previous pattern on the transmissive liquid crystal display 14 is erased. Thereafter, the thermal writing control device 17 sends the baton data of the second mask to the baton writing mechanism 16, and the pattern is drawn on the transmissive liquid crystal display 14 and transferred onto the wafer 8. Similarly, the exposure operation is repeated for the third and subsequent masks. Here, the half mirror 15 located on the optical path of the projected light can transmit the projected light without any particular problem.

In the embodiment shown in FIG. 1 described above, since the addressing method of the liquid crystal display is a matrix addressing method, the drawn image is expressed as a collection of dots, and unless it is reduced and projected, it will be a continuous line with overlapping adjacent dots. However, in the embodiment shown in Figure 3, the addressing method is a scanning method using a laser beam, so it is possible to draw continuous lines or any arbitrary pattern that is all black on the liquid crystal display. 1-size projection exposure method.

It is applicable to both a contact exposure method and a reduction projection exposure method. It goes without saying that in the configuration shown in FIG. 3, there is no need to manufacture a conventional photomask, there is no need to replace or install a mask, and the transmissive liquid crystal display can be sealed and kept from dust.

Further, in the above-mentioned embodiments, the present invention has been explained in detail using an active matrix driven transmissive liquid crystal display and a thermal writing phase change type transmissive liquid crystal display as examples of transmissive flat displays. As long as it is a flat display with a high contrast ratio, whether it is a simple matrix liquid crystal display other than the above, a ferroelectric liquid crystal display, or another flat display, the exposure apparatus of the present invention can be used in the same manner as in the above two examples. Can be used.

〔Effect of the invention〕

As explained above, the exposure apparatus according to the present invention draws a necessary mask pattern on a transmissive flat display and uses the displayed image as a mask pattern, a semiconductor integrated circuit, and an optical integrated circuit.

This system eliminates the need for conventional photomasks, which were manufactured in batches of several to ten or more for each type of thin film integrated circuits such as TPT integrated circuits, printed wiring boards for electronic circuits, and thick film integrated circuits such as ceramic wiring boards. , the following extremely excellent effects can be obtained.

First, there is no need to manufacture photomasks that are expensive and take several weeks to manufacture, and the development costs and product costs for the thin film integrated circuits and the like can be significantly reduced, and the development period can also be significantly shortened.

The second problem is the alignment operation between the photomask and photomask holder, which was previously required every time the photomask was replaced, and the alignment operation between the photomask holder and the projection exposure equipment main body during the manufacturing stage of thin film integrated circuits. 7. It is possible to omit any alignment operation, and the manufacturing time can be significantly shortened.

Third, by using a specific coordinate position of the transmissive flat display as a common coordinate origin for each mask pattern, positional deviations between patterns do not occur, and the decrease in yield due to conventional mask alignment errors is avoided. Fourth, the transmissive multi-plane display can be installed in a sealed structure that does not allow dust to enter, greatly improving the manufacturing yield of thin film integrated circuits and the like, and significantly reducing the cost of the product.

Fifth, even if it becomes necessary to modify the drawing pattern, it can be easily handled by modifying the pattern data stored in the memory in the control device, without actually manufacturing a photomask. The turnaround time for verification prototypes of circuits, etc. can be significantly shortened.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a structure using an active matrix driven transmissive liquid crystal display as a transmissive multi-plane display showing an embodiment of an exposure apparatus according to the present invention, and FIG. 2 is a schematic diagram of an active matrix driven transmissive liquid crystal display. FIG. 3 is a cross-sectional view of a configuration using a thermal writing phase change type transmission type display as a transmission multi-plane display showing another embodiment of the exposure apparatus according to the present invention, and FIG. FIG. 5 is an enlarged cross-sectional view of a main part of a transmissive display of a transition type, and is a cross-sectional view showing the configuration of a conventional reduction projection exposure apparatus. 1... e reduction projection exposure apparatus main body, 2φ... light source, 3
-----Condenser lens, 6#---Reduction projection system lens, T...Fist/X-Y stage, 8...Wafer, 9
... optical path, 10... ma) IJ drive type transmissive liquid crystal display, 11... control device, 12...
...Interface line, 13... Sealing plate, 14.
...Thermal writing phase change type transmissive liquid crystal display, 1
5... Half mirror 116... Bang writing mechanism, 1T... Thermal writing control device, 18... Bang erasing circuit, 20... TN liquid crystal layer, 21m, 21b
...Molecular orientation layer, 22a, 22bIII...Transparent electrode, 23. Thin film transistor (TPT) layer,
24m, 24b...transparent glass substrate, 25.
...Peripheral human resources, zsa, 26b...Polarizing plate, 30...Nine liquid crystal layers with regularly arranged smectic liquid crystal or cholesteric liquid crystal, 31m. 31b...Transparent electrode, 32m, 32b...
Transparent glass substrate, 33... input light, 34...
Projection light, 35@-...Laser beam. Patent applicant Nippon Telegraph and Telephone Corporation

Claims (1)

[Claims] In an exposure apparatus equipped with a mask pattern transfer device that transfers a mask pattern by exposing a substrate coated with a resist, the mask pattern transfer device is a transmissive flat display that draws a display image as a mask pattern. Characteristic exposure equipment.