JPH09236907A - Pattern forming device and lithography device formed by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the technique capable of processing a sufficient number of sheets of wafers for the specified time like a photolithographic technique with the high degree of freedom like electron beam photolithography by inducing the displacement of displaceable electrodes in correspondence to prescribed patterns by dealing with the potential impressed between these electrodes. SOLUTION: The mechanical displacement by the attraction force among reflection plates 20 around supporting beams 21 is induced by impressing the voltage between the reflection plates 20 and the electrodes 22. The parts where the light reflected by the reflection plates 20 is made incident on the lens of a lithographic device are determined by such mechanical action. Namely, the reflection plates 20 with which the mechanical displacement is induced by impressing the voltage between the reflection plates 20 and the electrodes 22 reflects the incident light in the direction different from the case the voltage is not impressed, thereby not supplying the light to the lens. The reflection plates 20 not impressed with the voltage reflects the light in a perpendicular direction and, therefore, the light is supplied to the lens by the reflected light. Then, the patterns corresponding to the displacement of the reflection plates 20 are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for forming a desired pattern by an electric signal, and more specifically, it relates to a technique for forming a pattern by a minute movable structure created by a micromachine technique. .

[0002]

2. Description of the Related Art A conventional pattern forming apparatus uses a reticle on which a pattern has already been formed, such as a stepper used for a photolithography process, and transfers the pattern on the wafer all at once by light. Alternatively, as in electron beam lithography, an electron beam is scanned based on a design pattern to form a pattern on a wafer.

[0003]

However, these conventional methods have the following problems and need a solution.

(1) In the stepper used in the photolithography process, the number of wafers that can be processed in a fixed time can be increased sufficiently, but there is no freedom to change the pattern, and it is necessary to create a corresponding reticle each time.

(2) In electron beam lithography, although there is a degree of freedom in changing patterns, the number of wafers that can be processed in a fixed time is small, and it is not suitable for mass production.

[0006]

The present invention has been made to solve the above-mentioned problems of the prior art, and the integrated pattern forming apparatus produced by the micromachine technique allows the degree of freedom as in electron beam lithography. It is possible to realize a technique in which the number of wafers that can be processed in a fixed time is sufficiently large, such as the photolithography technique. That is, an integrated pattern forming apparatus and a lithography method using the same are disclosed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A lithographic apparatus using an integrated pattern forming device produced by a micromachine technique according to the present invention is, as shown in FIG. 1, an integrated pattern forming device 5 and light supplied from a light source 6. And a reduction mirror 3 and a wafer stage 1. Wafer stage 1
The light corresponding to the pattern obtained from the integrated pattern forming device 5 is applied to the wafer 2 placed on the substrate 2 via the reduction lens 3.

The integrated pattern forming apparatus 5 is composed of, for example, an electrode 22, a conductive reflection plate 20 and a conductive support beam 21 formed on a substrate 100 as shown in FIG.
The reflector 20 is provided with necessary wiring via the support beam 21 and the substrate 100. By applying a voltage between the reflection plate 20 and the electrode 22, a mechanical displacement due to an attractive force between the reflection plates 20 around the support beam 21 is caused. Due to this mechanical movement, the portion of the light reflected by the reflection plate 20 is incident on the lens 3 of the lithographic apparatus shown in FIG. That is, a voltage is applied between the reflection plate 20 and the electrode 22 to cause a mechanical displacement, and the reflection plate reflects incident light in a direction different from that in the case where no voltage is applied to the lens 3. Since the reflector that does not supply light, while the voltage is not applied, reflects light in the direction perpendicular to the surface, these reflected light supplies light to the lens 3. Therefore, the integrated pattern forming device 5 forms a pattern corresponding to the displacement of the reflection plate.

An example is shown in plan view in FIG.
Among the reflectors 20 formed on the substrate 100 of the integrated pattern forming device 5 composed of a matrix of a plurality of reflectors, the reflector 12 shown by hatching with a rough interval in the drawing shows a voltage between the electrodes 22. It is applied and causes mechanical displacement to deflect light. On the other hand, in the reflection plate 11 shown by hatching closely spaced, no voltage is applied to the electrode 22,
Reflects light as it is. Therefore, the light reflected by the reflector 12 does not reach the wafer 2, whereas the light reflected by the reflector 1
The light reflected by 1 reaches the wafer 2 so that an inverted L-shaped pattern is formed on the wafer 2 in the example of FIG. The minimum size is the size of one reflector 20 and the lens 3
Is determined by the reduction ratio of. For example, when the size of one reflection plate 20 is 2 μm and the reduction ratio of the lens 3 is ⅕, the minimum size is 0.4 μm, and the size of one reflection plate 20 is 1 μm and the reduction ratio of the lens 3. Is 1/4, 0.2
5 μm. Therefore, the size of one reflector 12 is 4μ.
If m and the reduction ratio of the lens 3 are ¼, and 1000 × 1000 reflection plates 12 are arranged, the area that can be exposed by one integrated pattern forming device 5 is a 1000 μm square area.

20 × 2 of the integrated pattern forming device 5
When 0 pieces are arranged and exposed, a 20 mm square area can be exposed at one time. When the minimum processing size becomes smaller, the area that can be exposed by one integrated pattern forming apparatus becomes smaller. However, if the number of integrated pattern forming apparatuses arranged in parallel is increased, the exposure area can be sufficiently large and the throughput becomes sufficient.
Since the price of the integrated pattern forming apparatus is manufactured by the micromachine technology, it is possible to manufacture the integrated pattern forming apparatus at a cost of several hundred yen, which is economically sufficient.

If this combination is formed into a predetermined shape, an arbitrary pattern can be rapidly formed, and high-speed and highly flexible pattern transfer can be performed by using the lithographic apparatus using the integrated pattern forming apparatus shown in FIG. become.

The lithographic apparatus using the integrated pattern forming apparatus according to the present invention has a high engineering value because it provides an advanced lithographic technique having both the high speed of conventional optical lithography and the degree of freedom of electron beam lithography. .
The present technology is particularly effective when used in the following lithography process.

(1) Gate array wiring process.

(2) Trial manufacture of test lots for many types of devices and circuits.

(3) Read Only Me
mory: ROM) manufacturing.

(4) Manufacturing of a wafer in which chips having various circuits are mixedly mounted in one wafer.

For example, in the case of forming five types of circuits in one wafer, it was necessary to prepare five different types of mask sets in the prior art, but according to the present invention, one trial production is required. Therefore, the labor can be significantly reduced.

Embodiment 1 This embodiment discloses the structure of an integrated pattern forming device. Not only the reflective type shown in FIG. 2 but also a transmissive type is possible. FIG. 4 shows an example of a transmissive type, in which a transparent electrode 27 made of an oxide of indium-tin is formed on a transmissive type substrate 26 made of quartz glass, and aluminum is further provided via a conductive support beam 25. The state which formed the reflecting plate 28 consisting of is shown. A transparent electrode 24 made of indium-tin oxide is formed on the substrate 23 made of quartz glass with a distance of about 5 μm from this structure. By applying a voltage between the reflection plate 28 and the electrode 24, the reflection plate 28 is attracted to the electrode 24 side and moved from a position parallel to the substrate 26 so that light can pass therethrough. After passing light for a certain period of time and ending the exposure, the applied voltage is returned to the ground potential or the reflection plate 2
8 and the transparent electrode 27 to apply a voltage to the reflector 28
To the original position. The transparent electrode 27 is not always necessary, but it is effective for high-speed operation of restoration of the reflection plate 28.

FIG. 5 is a diagram showing another example of the transmission type integrated pattern forming apparatus. Transparent electrode 32 on glass substrate 33
After forming, the conductive transparent plate 30 is formed through the conductive support beam 31. By applying a voltage between the transparent electrode 32 and the transparent plate 30, the transparent plate 30 is displaced with the support beam 31 as a fulcrum. If the distance between the transparent electrode 32 and the transparent plate 30 is set to an integral multiple of 1/2 of the exposure wavelength, the transparent plate 30 is displaced as shown in the example of FIG. If it deviates from an integer multiple of 2, light will pass, but otherwise it will not pass. This is due to the interference effect of light, and since the on / off light intensity ratio is as large as 20 or more, it is possible to generate a pattern with a slight movement of the transparent plate 30.

Embodiment 2 This embodiment discloses a lithographic apparatus using a transmissive integrated pattern forming device produced by the micromachine technology according to the present invention.

FIG. 6 shows an overview of a lithographic apparatus similar to that of FIG. In the configuration including the light source 6, the reduction lens 3, the stage 1, and the wafer 2, the pattern formed by the transmissive integrated pattern forming device 7 is imaged on the wafer 2 by the ultraviolet light from the light source 6. With such a configuration, if a predetermined circuit pattern is input to the transmissive integrated pattern forming device 7, the wafer 2
A predetermined circuit pattern is generated on the top. Therefore, it is possible to eliminate a process that requires a long time such as manufacturing a mask in the conventional optical lithography technique and drawing in the electron beam lithography technique, and it is possible to realize high production efficiency.

In general, the transmission type integrated pattern forming apparatus has a lower light intensity and a longer time required for one exposure than the reflection type, but the contrast can be increased. Also, the switching time is faster in the reflective type. Therefore, it is necessary to decide whether the integrated pattern forming apparatus is of a transmissive type or a reflective type in consideration of these factors.

Embodiment 3 This embodiment discloses an arrangement example of the integrated pattern forming apparatus.

FIG. 7 shows the structure of a one-dimensional integrated pattern forming apparatus. Also in this example, similarly to the example of FIG. 3, among the reflectors 20 formed on the substrate 100, the reflector 12 shown by hatching with a rough interval in the figure applies a voltage between the electrodes 22 and mechanically The light is deflected by causing various displacements. On the other hand, the reflection plate 11 shown by hatching closely spaced,
No voltage is applied between the electrodes 22 and the light is reflected as it is. By arranging a plurality of such one-dimensional integrated pattern forming devices in parallel and transferring the pattern generated by each one-dimensional integrated pattern forming device to the wafer while scanning in the width direction, the two-dimensional integrated pattern forming device shown in FIG. Lithography similar to that using an array is possible.

The advantage of the one-dimensional array is that the switching speed is fast and that one side can be made longer as compared with the two-dimensional array, so that the final pattern transfer speed can be made relatively fast.

Embodiment 4 This embodiment discloses a method of manufacturing an integrated pattern forming device. The structure disclosed in this embodiment is the reflective structure shown in FIG. 2, but a transmissive structure can be realized by almost the same method. The manufacturing method shown in the present embodiment uses ordinary integrated circuit technology, and it is easy for a skilled engineer to give optimum values for the forming method, film thickness and the like.

In FIG. 8A, an insulator 52 made of silicon oxide and having a thickness of 2 μm is formed on a silicon substrate 51.
Wiring layer 5 made of aluminum and having a thickness of 1 μm and a width of 2 μm
3 shows a state in which 3 is formed in the direction parallel to the drawing, and further an insulator 54 of silicon oxide having a thickness of 2 μm is formed so as to planarize the surface. FIG. 8B shows a structure prepared in this way, which is again made of aluminum and has a thickness of 1 μm and a width of 3
After forming the wiring layer 55 of μm in the direction perpendicular to the drawing, the thickness 10
A state in which a 0 nm silicon nitride film 56 is deposited is shown. This wiring layer 55 is for functioning as the electrode 22 in FIG. FIG. 8 (c) shows a further CVD
Method, a silicon oxide film 57 is deposited to a thickness of 2 μm, the surface is flattened, a through hole is formed by a lithography technique, and the hole is filled with tungsten formed by a CVD method to form a conductive support beam 58. The state which formed the structure which should become is shown. In FIG. 8D, a structure to serve as the reflection plate 59 is formed of polycrystalline silicon on the surface of the substrate thus prepared by using a lithography technique, and the silicon oxide film 57 is covered with hydrofluoric acid (fluorine). Acid) shows the state removed in the solution. Gold having a thickness of 100 nm was deposited on the surface of the reflection plate 59 to increase the reflectance.

The aluminum wiring layer 53 and the aluminum layer 55 form a so-called matrix-structured electrode relationship, and a necessary reflection plate 59 is tilted by selectively applying a voltage between them. You can It is known that the interaction between pixels can be avoided by devising a voltage application method, and this is not the essence of the present invention.

Although the integrated pattern forming device can be manufactured by the method disclosed in the above embodiments, it goes without saying that the method is not limited to the above method in order to realize the structure of the present invention.

Fifth Embodiment In the fourth embodiment, in order to tilt the reflecting plate 59, a method of applying a voltage between electrodes which are orthogonal to each other is used. However, a portion for storing charges is formed under each reflecting plate 59, This allows the reflector to be tilted.

In FIG. 9A, an insulator 62 made of silicon oxide and having a thickness of 2 μm is formed on a silicon substrate 61, and a wiring layer 63 made of aluminum and having a thickness of 1 μm and a width of 2 μm is formed.
Are formed in a direction parallel to the drawing, and an insulator 64 made of silicon oxide and having a thickness of 2 μm is formed so as to flatten the surface, and an island structure 65 made of polycrystalline silicon and having a thickness of 0.1 μm is formed again. It is formed at a position where a reflection plate is to be formed for each pixel. The island structure 65 has a continuous structure in which polycrystalline silicon is connected to each other. After depositing a silicon nitride film 66 having a thickness of 100 nm on the structure thus prepared, a wiring layer 67 having a width of 0.3 μm to serve as a gate is formed in the vertical direction of the drawing, and the same method as in Example 4 is performed. 2 shows a state in which the structure to be the tungsten supporting beam 68 and the structure to be the reflecting plate 69 formed by the CVD method are formed of polycrystalline silicon. Gold having a thickness of 100 nm was deposited on the surface of the reflection plate 69 to increase the reflectance.

FIG. 9B shows the relationship between the island-shaped structure 65 and the wiring layer 67 to be the gate in a plan view of only one pixel. In this figure, the silicon nitride film 66 is omitted. The island structure 65 includes a wiring layer 67 that is to be a gate for each pixel.
Thus, the island-shaped structure 65 of each pixel can be equivalently separated from the associated conductive portion. In order to apply the voltage to the island-shaped structure 65, the voltage may be applied to the conductive portion connecting the island-shaped structures while applying the voltage to the gate 67. In this way, charges can be stored in the island structure 65. When a voltage is applied to the aluminum wiring layer 63, a force acts between the aluminum wiring layer 63 and the island-shaped structure 65 in which the charges are accumulated, and the reflection plate 5
It is possible to tilt 9 to form a pattern.

FIG. 9C shows the overall structure of one pixel in a plan view. Also in this case, the insulating layer was omitted.

[0034]

As shown in the above embodiments, according to the present invention, it is possible to realize an integrated pattern forming apparatus, which has a greater degree of freedom than conventional optical lithography. And because it is possible to realize a high-performance lithographic apparatus with a higher throughput than electron beam lithography,
The economic effect is great.

[Brief description of drawings]

FIG. 1 is a diagram showing the concept of the structure of a lithographic apparatus using an integrated pattern forming apparatus according to the present invention.

FIG. 2 is a view showing the concept of an integrated pattern forming device.

FIG. 3 is a diagram showing a concept of a basic structure of a two-dimensional integrated pattern forming device including a matrix of reflecting plate rows.

FIG. 4 is a view showing the concept of the structure of a transmissive integrated pattern forming device.

FIG. 5 is a view showing the concept of another example of the structure of the transmissive integrated pattern forming device.

FIG. 6 is a diagram showing a concept of a structure of a lithographic apparatus using a transmissive integrated pattern forming apparatus.

FIG. 7 is a view showing the concept of the configuration of a one-dimensional integrated pattern forming device.

8A to 8D are views showing the concept of a manufacturing procedure of the integrated pattern forming device according to the present invention.

9A to 9C are views showing another example of the manufacturing procedure of the integrated pattern forming apparatus according to the present invention.

[Explanation of symbols]

1: Wafer stage, 2: Wafer, 3: Lens, 4: Half mirror, 5: Reflective integrated pattern forming device, 6:
Light source, 7: Transmission type integrated pattern forming device, 10, 1
3, 41: Substrate, 20: Reflector, 21, 25, 31, 4
8: Support beams, 22, 24, 27, 32, 43, 45, 4
9: electrode, 42, 44, 47: silicon oxide film, 51,
61: silicon substrate, 52, 62: silicon oxide, 5
3, 63: wiring layer, 54, 64: insulator, 55, 67:
Wiring layers, 56 and 66: silicon nitride film, 57: silicon oxide film, 58 and 68: support beams, 59 and 69: reflector plate, 6
5: Island structure.

Claims (5)

[Claims] 1. A plurality of electrodes formed on a substrate, a displaceable electrode arranged at a position corresponding to the electrodes and configured to reflect or transmit light emitted to the electrodes, both electrodes. And an electric circuit for selectively applying a potential between the electrodes, wherein the displaceable electrodes are displaced corresponding to a predetermined pattern in response to the potential selectively applied between the electrodes. Integrated pattern forming apparatus. 2. The integrated pattern forming apparatus according to claim 1, wherein the substrate on which the plurality of electrodes are formed and the electrodes are transparent, and the displaceable electrodes are transparent. 3. A plurality of electrodes formed on a substrate are configured into a plurality of islands that are electrically connected but structurally independent, and charges can be stored in each island structure. The integrated pattern forming apparatus according to claim 1, wherein the displacement of the displaceable electrode is controlled as a control. 4. A plurality of electrodes formed on a substrate, a displaceable electrode arranged at a position corresponding to the electrodes and capable of reflecting or transmitting light irradiated to the electrodes, both electrodes. An integrated circuit forming an electric circuit for selectively applying a potential between the electrodes, wherein the displaceable electrodes are displaced corresponding to a predetermined pattern in response to the potential selectively applied between the electrodes. A device, means for irradiating the displaceable electrode with light, and means for holding a wafer that is irradiated with a pattern obtained by reflecting or transmitting the light irradiated on the displaceable electrode. A lithographic apparatus comprising: 5. The lithography according to claim 4, wherein the integrated pattern forming devices having an electrode array for pattern formation having a one-dimensional structure are arranged in parallel to form an integrated pattern forming device having an equivalent two-dimensional structure. apparatus