TW559895B - Exposure system and exposure method thereof - Google Patents

Abstract

The present invention discloses an exposure system and an exposure method thereof, in which a liquid is provided between the wafer to be exposed and the lens to increase the refractive index in the exposure path. The exposure system at least comprises: a liquid container to carry the liquid; a wafer supporting device installed inside the liquid container to support the wafer, so that the wafer surface contacts the liquid; and an exposure device having a lens, which is installed on top of the wafer inside the liquid container, so that the lens surface contacts the liquid.

Description

559895

FIELD OF THE INVENTION The present invention relates to a semiconductor manufacturing apparatus and a method of using the same, and more particularly, to an exposure system and an exposure method thereof. Relevant technical description: In the manufacturing process of semiconductor integrated circuits, the lithography process occupies a very important position. I can use this process to accurately define the designed pattern on the photoresist layer. 9 Then The pattern of the photoresist layer is transferred to the semiconductor substrate by using a remaining process to obtain a desired circuit structure. Generally speaking, the lithography process mainly includes priming, coating, pre-baking (or soft baking), exposure (exposure), post-exposure processing, development, and hard baking, etc. Several steps. Among them, the resolution of the exposure program is a key factor in whether the component accumulation can be further improved. All major semiconductor manufacturers have actively invested in research and development in order to achieve a higher level. Based on the analysis of optical principles, the resolution of the exposure machine is proportional to the wavelength of the light source used, that is, the shorter the wavelength of the exposure light source, the smaller the resolution. In terms of the current commercial semiconductor manufacturing process, exposure equipment has evolved from using light sources with wavelengths of 436nm (g-line) and 365nm (i-line) to deep ultraviolet light with a wavelength of 248nm or shorter (193nm) Deep UV) range of light sources, even research and development towards the wavelength of 157 [1111, in response to the increasing demand for component accumulation. When entering the new era of optical lithography (p0st-Optical Lithography), an ultra-short ultraviolet light (EUV) with a wavelength of 13nm has been developed (also known as point light source X-ray, soft X-ray). The resolution can be improved below about 50nm.

559895 V. Description of the invention (2) Ren Qin 'As the element size will continue to shrink, the gap of the mask pattern will become as small as a grating, and the effect of the light wave diffraction effect will be more obvious than in the past. The resist layer also withstands a certain amount of light intensity, resulting in a decrease in exposure contrast (Contrast), which is not conducive to the subsequent development step. Generally speaking, the resolution (resolution) R is proportional to the wavelength of the incident light and is inversely proportional to the numerical aperture NA. 0 λ / NA (i) and NA = n * sin0 (2) can be obtained h · A / (n.sin (3), where 'kl is a constant, n is the radiosity of the optical transmission medium, and 0 is the angle of incidence. In order to improve the resolution R, the wavelength of the light source is reduced only. Can not meet the semiconductor needs of high integration, therefore, an immersion lithography technology (Cummers ion lithography) was proposed, simply drop a drop of liquid with a high refractive index on the wafer surface and the surface of the exposure lens to improve the numerical aperture NA, further Increase exposure resolution R. In addition to improving the resolution R, another optical tube needs to be considered at the same time: I depth of focus, D〇F = k3 · A / (sin2 Θ / 2) (4) From formula (3) and formula (4) The following results can be calculated:

559895

Article i Ί 牛 Ί n ON sin6〇 ^ TrT ^ Θ ^ imme r / R a ir DOFimM € r / DOFiir ΙΕΙφΊ; ~ 1 1.5 0. 9 " oTl ~ 〇. 67 0. 67 1 lT. 5 0 9 ΓΓ. 6 1 1 · 88 IT 〇1 1.5 0. 9 " 〇T7 0. 857 1. 316 Among them, n. Indicates the refractive index of air; 11 indicates the refractive index of liquid; Θ. Is the angle of incidence when air is the light transmission medium; 0 is the angle of incidence when air is the light transmission medium;

Rair is the resolution when air is used as the light transmission medium;

Rimmer is the resolution when air is used as a light transmission medium; D〇Fair is the depth of focus when air is used as a light transmission medium; D〇Fair is the depth of focus when using air as a light transmission medium. / Yan According to the results in Table 1, under the condition 1, it shows that although the immersion lithography technology can improve the resolution R, it can not improve the depth of focus [) 〇1? However, in the conditions 2 and 3, the use of immersion Lithography technology, together with adjusting the incident angle Θ ', can change the focal depth dof and the resolution r at the same time. By appropriately adjusting the incident angle < 9, the results of simultaneously improving the focal depth Dof and the resolution R can be obtained ( If condition 3) ^ It can be seen that the immersion lithography technology can break through the optical limitation 'will open a new era for the semiconductor lithography process. However, the practical application of immersion lithography as described above in semiconductors

0503-8206T ^ f; TSMC2002-0119; Felicia.ptd page 6 559895

V. Explanation of the invention (4) The following problems will occur during the manufacturing process: 1. During the exposure process, when light enters the photoresist, it will cause the photoresistance to react and release gas to generate bubbles, making the liquid homogeneity. Worse, distort the image, and reduce the refractive index. 2. Since the exposure machine must move quickly to scan or step the wafer during the exposure, it often causes frictional heat generation, which makes the homogeneity of the liquid worse, which distort the image and cause the refractive index to be unstable. 3. Impurities and pollutants will fall into the liquid, and will be exposed in the exposure path, causing defects. In view of this, in order to solve the above problems, the main object of the present invention is to provide an exposure system using immersion lithography technology, so as to avoid the above problems. SUMMARY OF THE INVENTION One of the objectives of the present invention is to provide a new exposure system by which the immersion lithography technology can be implemented. In order to achieve the above object, the present invention provides an exposure system and an exposure method thereof. The device mainly includes: a liquid tank for carrying the liquid; a wafer supporting device provided inside the liquid tank to support the wafer so that the surface of the wafer is in contact with the liquid; and an exposure device A lens is provided above the wafer inside the liquid tank, so that the surface of the lens is in contact with the liquid. As mentioned above, the liquid tank further includes: a protective cover provided on the top of the liquid tank to seal the liquid tank; a liquid inlet for introducing the liquid; a liquid outlet for discharging the liquid; Reflow

559895 V. Description of the invention (5) The pipeline 'circulates the liquid between the liquid tank and the return pipeline; a pump is used to drive the liquid to circulate between the liquid tank and the return pipeline A filtering device provided inside the above-mentioned return line to 'transition bubbles and impurities generated by liquid flow; a temperature adjusting device connected to the liquid tank to adjust the temperature of the liquid' to maintain the liquid at a constant temperature And a measuring system for chaos, which is arranged on the inner wall of the liquid tank to detect the position of the exposure device. As mentioned above, the wafer supporting device further includes: a vacuum system for holding the wafer. And an inclination adjusting device for adjusting the inclination of the surface of the wafer so that the surface of the wafer is parallel to the surface of the lens. As described above, the above-mentioned exposure device may be a scan-and-stepper (scan-and- repeat mask aligner), step-and_repeat mask aligner, or mask aligner, and the exposure device can be moved vertically for focusing or horizontally for exposure. As mentioned previously, the exposure device of the present invention may be a 1: 1 exposure system. The above exposure device includes a photomask, which replaces the lens with a photomask, and must be in direct contact with the liquid. The present invention also provides an exposure method using the above-mentioned exposure system. The main steps of the method include: first, providing a liquid Zhao trough. Next, a substrate is set inside the liquid tank. Next, a liquid is injected into the liquid tank to cover the surface of the substrate. Then, an exposure device is set above the substrate, wherein the exposure device has a lens, and the above

0503-8206TW: TSMC2002-0119; Felicia.ptd page 8 559895 V. Description of the invention (6) The lens surface is in contact with the above liquid. Finally, an exposure process is performed on the substrate by using a light source to pass through the lens and the liquid. As mentioned above, the liquid system is any liquid with a refractive index greater than 1 (air), such as water, glycerine or perfluorinated polymers. As mentioned before, before performing the above-mentioned exposure procedure, it further includes: adjusting the position height of the above-mentioned exposure device for focusing. As mentioned before, before performing the above-mentioned exposure procedure, it is also included to adjust the horizontal position of the exposure device 'to align the predetermined position of the wafer. As mentioned before, before implementing the exposure procedure, the method further includes: adjusting the inclination of the wafer surface so that the wafer surface is parallel to the lens surface. As mentioned above, wherein the substrate can be fixed inside the liquid tank by a vacuum system. Example: Hereinafter, an embodiment of the present invention will be described with reference to the sectional view of the exposure system in FIG. 1 and the top view of the exposure system in FIG. 2, and another embodiment of the present invention will be described with reference to a partial sectional view of the exposure system in FIG. 3. example. The exposure system of the present invention includes a liquid tank 100 through which a liquid 10 can be injected through a liquid inlet 104, and a liquid outlet 10 is provided to discharge the liquid 10 described above, so that the liquid inside the liquid tank 100 can Update regularly and keep clean. The liquid 10 can be any liquid with a high refractive index (air), such as water, glycerine or perfluoropolymers, and water is preferred. Provide the above liquid

559895

The purpose of i〇 is to use the above liquid as a light transmission medium, increase the refractive index of the exposure path, and at the same time increase the resolution and depth of focus of the exposure process. ^ Seal the liquid tank 100 to prevent any contaminants from falling into the liquid tank 100, change the refractive index of the liquid 10, or affect exposure on the light transmission path. In addition, the protective cover 102 is connected to an exposure device 500, and the thickness of the protective cover 102 increases as it approaches the exposure device 500, that is, the closer to the protective cover 102 of the lens 300, the thicker the protective cover 102 can be. The liquid 10 flows easily. And 'the liquid tank 100 is connected to a return line 108, and a pump 110 is set in the return line 10 to drive the' liquid 10 'and the liquid 10 is placed in the liquid tank 100. It circulates with the return line 108. In addition, a filtering device jj 2 ′ such as a filter screen or foam can be provided inside the above-mentioned return line 丨 〇8, and the bubbles released from the chemical reaction of the photoresist during the exposure process through the flowing liquid 〇 and from the outside The dropped impurities are filtered and removed together to maintain the homogeneity of the liquid and keep the refractive index stable. Furthermore, a temperature regulating device 114 may be provided and connected to the liquid tank 100 to adjust the temperature of the liquid 10 to maintain the liquid 10 at a constant temperature. The temperature of the liquid can be controlled by the above-mentioned temperature adjusting device 114, and the heat generated by the friction caused by the rapid movement of the exposure device 500 over different wafer positions to avoid affecting the homogeneity and refractive index of the liquid can be avoided. The exposure system of the present invention further includes a wafer supporting device 200, for example, a wafer supporting table is disposed inside the liquid tank 100 to support a wafer 20 so that the surface of the wafer 20 and the wafer 20 The liquid 10 was in contact. Above crystal

0503-8206TWf; TSMC2002-0119: Felicia.ptd Page 10 ---- 559895 V. Description of the Invention (8) "-The round branch device 200 can use a vacuum system 202 to suck the wafers. And, a tilt adjusting device 204 is provided to adjust the tilt of the surface of the wafer 20 described above. The exposure system of the present invention still includes an exposure device 500, which can be any conventional exposure machine, such as a scan-and-repeat mask aligner, step — and — repeat mask aligner) or mask aHgner, and the exposure device 500 can be moved vertically, adjusted to an appropriate position for focusing, or moved horizontally. 'Select an appropriate position corresponding to the above-mentioned wafer 20 to perform Exposure 'or by adjusting the tilt adjustment device 204 so that the surface of the wafer 20 is parallel to the surface of the lens 300. The exposure device 5'00 is disposed above the wafer 20, and includes at least a light source, a photomask, and a lens 300, and the lens 300 must be in contact with the liquid 10. It should be noted that it is necessary to fill the liquid 10 between the surface of the wafer 20 and the surface of the lens 300, and use the liquid 10 as a light transmission medium for exposure. In addition, if the exposure device uses 1: 1 exposure By way of example, another embodiment of the exposure apparatus 500 described above includes a photomask 600, as shown in FIG. 3. Similarly, it is necessary to fill the liquid 10 between the surface of the wafer 20 and the surface of the mask 600, and use the liquid 10 as a light transmission medium during exposure. As mentioned above, the exposure system of the present invention may be provided with a debt measurement system 400 as required. For example, a conventional detection system is provided with a detection mirror surface around the inner wall of the liquid tank above, and the above can be observed through the mirror surface. Wafer 2 0 and above

0503-8206W; TSMC2002-0119; Felicia.ptd page 11 559895

Mask The position of the lens 300 or mask 600 mentioned above is convenient to detect the position of the upper lens 300 or 600, so as to ensure that the lens 300 or mask 600 accurately corresponds to the position on the wafer 20 where exposure is desired. When using the exposure system as described above, the exposure device 500 will provide a light source to pass through the lens 300 or the mask 300, pass through the liquid 20, and use the liquid as a light transmission medium. The above-mentioned crystal applies an exposure procedure. Only the advantages of the invention: the above-mentioned invention has the following advantages: 1. According to the exposure system and the exposure method of the invention, a liquid is added between the wafer surface and the lens surface, so that the exposure path is increased. The refractive index is increased, Furthermore, the resolution and depth of focus of the exposure process are improved at the same time. According to the pump and filter device of the present invention, can impurities and wafers be removed? It prevents the release of gas due to a chemical reaction during exposure to maintain the homogeneity of the liquid and maintain a stable refractive index. 3 · According to the stability, to move quickly. 4 · According to the liquid, within the spirit and scope of the present invention. When the temperature adjusting device of the present invention, the temperature of the liquid can be controlled. The heat generated by friction above the circular position affects the homogeneity and refractive index of the liquid. The protective cover of the liquid tank of the present invention can prevent pollutants from falling into the light path to form defects and affect the exposure result. Although the above is disclosed in the preferred embodiment, it is not intended to limit the scope. Any person skilled in the art can do various modifications and retouches without departing from the present invention. Therefore, the present invention is attached as follows. The ones defined in the scope of patent application shall prevail.

559895 Brief description of the drawings In order to make the above-mentioned objects, features, and advantages of the present invention more obvious and easy to understand, a preferred embodiment is given below, and in conjunction with the attached drawings, the detailed description is as follows. Sectional view of an exposure system according to a preferred embodiment of the invention. Figure 2 is a top view of an exposure system according to a preferred embodiment of the present invention. FIG. 3 is a partial cross-sectional view of an exposure system according to another preferred embodiment of the present invention. Explanation of symbols: 10 ~ liquid; | 2 0 ~ wafer; 100 ~ liquid tank; 102 ~ protective cover; 104 ~ liquid inlet; 106 ~ liquid outlet; 108 ~ return line; 11 ~~ pump; 11 2 ~ filter device; 114 ~ temperature adjustment device; 200 ~ wafer support device; 202 ~ vacuum system; 204 ~ tilt adjustment device; (300 ~ lens;

0503-8206W; TSMC2002-0119; Felicia.ptd page 13 559895 Simple description of the drawings 4 0 ~ detection system; 500 ~ exposure device; 600 ~ photomask.

1 ^ 1 0503-8206T ^ f; TSMC2002-0119; Felicia.ptd page 14

Claims (1)

559895 Light, including an exposure system, is suitable for exposing a wafer to a liquid tank through a liquid, and supporting the wafer with a wafer support device, so that the above and an exposure device have the lens surface and the upper surface. The patented liquid tank further includes: a sealed liquid tank. 3. If the patent application fan cover and the above exposure device are close to the above exposure device, and if the patent application fan liquid tank further includes: a liquid inlet, with a liquid outlet, 5 · If the patent application liquid tank further includes: One cycle between the above-mentioned return lines. If the patent application patent liquid tank further includes: A group and the above-mentioned return line carry the liquid; It is arranged inside the liquid tank to support the wafer to be exposed. The surface is in contact with the liquid; a lens is disposed above the wafer, and the liquid is in contact. The exposure system according to item 1, wherein the protective cover is disposed on the top of the liquid tank, and is used to surround the exposure system according to item 1, wherein the devices are connected, and the thickness of the protective cover increases with the increase. The exposure system described in item 1 above, wherein the above-mentioned liquid is introduced; and the above-mentioned liquid is discharged. The exposure system according to item 1, wherein the flow line allows the liquid to flow in the liquid tank and the ring. The exposure system according to item 5, wherein the pump is used to drive the liquid to circulate in the liquid tank. 0503.8206W; TSMC2002.0119: Felicia.ptd Page 15 559895 VI. Patent application scope 7 · The exposure system described in item 6 of the patent application scope, wherein the above liquid tank further includes: a filtering device arranged on the above-mentioned return pipe Inside the circuit, it is used to filter bubbles and impurities generated by liquid flow. 8. The exposure system according to item 1 of the scope of the patent application, wherein the liquid tank further includes: a temperature adjustment device connected to the liquid tank to adjust the temperature of the liquid and maintain the liquid at a constant temperature. 9. The exposure system according to item 丨 of the scope of patent application, wherein the wafer supporting device further includes a vacuum system for holding the wafer. I. The exposure system according to item 1 of the scope of the patent application, wherein the wafer supporting device further includes: an inclination adjusting device for adjusting the inclination of the wafer surface so that the wafer surface is parallel to the above 'Lens surface. II. The exposure system described in item 1 of the scope of patent application, which further includes a debt measurement system, which is arranged on the inner wall of the liquid tank to detect the position of the exposure device. 1 2 · The exposure system described in item 1 of the scope of patent application, wherein the exposure device is a scan — and_repeat mask aligner 〇 1 3 · The exposure described in item 1 of the scope of patent application System, in which the above-mentioned exposure device is a step-and-repeat mask aligner 〇, 14. The exposure system as described in item 1 of the patent application scope, wherein the above-mentioned exposure device is a mask-alignment exposure machine (Mask aligner). 1 5 · The exposure system according to item 1 of the scope of patent application, wherein the exposure device uses vertical movement for focusing. 559895 VI. Scope of Patent Application 16 · The exposure system described in item 1 of the scope of patent application, wherein the above-mentioned exposure device uses horizontal movement for exposure. 17. An exposure method suitable for exposing a substrate through a liquid, including: providing a liquid tank filled with the liquid, and the substrate is disposed inside the liquid tank, and the liquid covers the substrate. A surface to be exposed; an exposure device is provided above the substrate, wherein the exposure device has a lens and the lens surface is in contact with the liquid; and a light source is used to pass through the lens and the liquid to perform an exposure procedure on the substrate. 18. The exposure method according to item 17 of the scope of the patent application, wherein the liquid includes water, glycerine or perfluoropolymers. 19. The exposure method according to item 17 of the scope of patent application, wherein before performing the above-mentioned exposure procedure, it further comprises:-adjusting the position height of the above-mentioned exposure device for focusing. 20 · The exposure method as described in item 17 of the scope of patent application, wherein before performing the above-mentioned exposure procedure, it further comprises: adjusting the horizontal position of the above-mentioned exposure device 'to align the predetermined position of the above-mentioned wafer. 21. The exposure method according to item 17 of the scope of patent application, wherein before performing the above-mentioned exposure procedure, it further comprises: adjusting the inclination of the wafer surface 'so that the wafer surface is parallel to the lens surface. 2 2 · The exposure method described in item 17 of the scope of patent application, wherein the above 0503-8206W; TSMC2002.Q119; Felicia.ptd page 17 559895 6. The scope of the patent application The exposure device is a scan-and-repeat mask aligner ° 23 · If the scope of patent application is 17 According to the exposure method, the exposure device is a step-and-repeat mask aligner ° 2 4 · The exposure method according to item 17 of the scope of patent application, wherein the exposure device is A mask aligner. 25. The exposure method according to item 17 of the scope of patent application, wherein the liquid tank further includes: a protective cover provided on the top of the liquid tank to seal the liquid tank. 26. The exposure method according to item 17 of the scope of the patent application, wherein the liquid tank further includes: a liquid inlet provided at the bottom of the liquid tank; and a liquid outlet provided at the bottom of the liquid tank. 27. The exposure method according to item 17 of the scope of the patent application, wherein the liquid tank further includes: a return line that circulates the liquid between the liquid tank and the return line. 2 8 · The exposure method according to item 27 of the scope of patent application, wherein the liquid tank further includes: a pump for driving the liquid to circulate between the liquid tank and the return line. 29. The exposure method according to item 28 in the scope of the patent application, wherein the liquid tank further includes: a filtering device disposed inside the return line to filter bubbles and impurities generated by the flow of the liquid vessel. 3 0 · The exposure method described in item 17 of the scope of patent application, wherein the above 0503-8206TWf; TSMC2002-0119; Felicia.ptd page 18 559895 6. Scope of patent application --- The liquid tank further includes a temperature adjustment device connected to the liquid tank to adjust the temperature of the liquid , Keep the liquid constant temperature. 31. The exposure method according to item 17 of the scope of patent application, wherein the substrate is fixed inside the liquid tank by a vacuum system. 32 · —An exposure system adapted to expose a wafer through a liquid, including: a liquid tank 'to carry the liquid; a wafer support device disposed inside the liquid tank to support the wafer 'Making the surface of the wafer to be exposed in contact with the liquid and the tooth' and an exposure device having a photomask disposed above the wafer and contacting the surface of the photomask with the liquid. 33. The exposure system according to item 32 of the scope of patent application, wherein the liquid tank further includes: a protective cover provided on the top of the liquid tank to seal the liquid tank. 34. The exposure system according to item 32 of the scope of patent application, wherein the protective cover is connected to the exposure device, and the thickness of the protective cover increases as it approaches the exposure device. 35. The exposure system according to item 32 of the scope of the patent application, wherein the liquid tank further includes: a liquid inlet for introducing the liquid liquid; and a liquid outlet for discharging the liquid. 36. The exposure system according to item 32 of the scope of patent application, wherein the liquid tank further includes: a return line for allowing the liquid to be in the liquid tank 0503-8206W: TSMC2002-0119; Felicia.ptd Page 19 559895 6. Scope of patent application-Circulation flow with the above return pipeline. … 37. The exposure system described in item 36 of the scope of patent application, wherein the upper body tank further comprises a pump for driving the liquid to circulate between the liquid tank and the return line. : 38. The exposure system according to item 37 of the scope of patent application, wherein the liquid tank further includes: a pass device, which is provided inside the above-mentioned return line 'to filter bubbles and impurities generated by the liquid flow. 39. The exposure system according to item 32 of the scope of patent application, wherein the liquid Zhao tank further includes: a temperature adjusting device connected to the liquid tank to adjust the temperature of the liquid and maintain the liquid at a constant temperature. 40. The exposure system described in item 32 of the patent application scope is blunt, wherein the wafer support device further includes: a vacuum system for holding the wafer. 41. The exposure system according to item 32 of the scope of patent application, wherein the wafer supporting device further includes: an inclination adjusting device for adjusting the inclination of the wafer surface so that the wafer surface is parallel to the photomask Surface 0 42. The exposure system as described in item 32 of the scope of patent application, further comprising: a detection system disposed on the inner wall of the liquid tank to detect the position of the exposure device. 43. The exposure system described in item 32 of the scope of patent application 'wherein the above-mentioned exposure device is a scan-and-repeat mask aligner 〇 (4 4 · As stated in item 32 of the scope of patent application The exposure system described above Page 20 0503-8206W; TSMC2200.2.0ii9; Felicia.ptd 559895 6. Application scope of patent --- The exposure device is a step-and_repeat mask aligner. 45. The exposure system according to item 32 of the scope of patent application, wherein the exposure device is a mask aligner. 4 6 · The exposure system according to item 32 of the scope of patent application, wherein the exposure device uses vertical movement for focusing. 4 7 · The exposure system according to item 32 of the scope of patent application, wherein the exposure device uses horizontal movement for exposure. 48 · —An exposure method suitable for exposing a substrate through a liquid, including: providing a liquid tank filled with the liquid, and the base and the bottom are arranged inside the liquid tank, wherein the liquid covers the substrate A surface to be exposed; an exposure device is provided above the substrate, wherein the exposure device has a photomask, and the surface of the photomask is in contact with the liquid; and a light source is used to pass through the photomask and the liquid to implement the substrate An exposure program. 4 9 · The exposure method as described in item 48 of the scope of patent application, wherein the liquid includes water, glycerine or aerobic polymer (perfluoropolymers) 〇 50. The exposure method according to item 48 of the patent application scope, wherein before performing the above-mentioned exposure procedure, the method further comprises: adjusting the position height of the above-mentioned exposure device for focusing. !! 5 1 · The exposure method described in item 48 of the scope of patent application, wherein 0503-8206TWf; TSMC2002-0119; Felicia.ptd page 21 559895 Before performing the above exposure procedure, set the horizontal position of the exposure device in m, +, and B to adjust the position of the exposure device 对准 to align the predetermined position of the wafer. The exposure method described in item 48 of the m patent is applied, wherein the production, so that the above-mentioned method further includes: adjusting the inclination of the surface of the wafer. The circular surface is parallel to the surface of the mask. … 53. The exposure method as described in item 48 of the scope of patent application, wherein the exposure device is a scan-and-stepper (scan-and-: repeat mask aligner) 〇 ... 54 The exposure method according to item 48, wherein the exposure device is a step-and-repeat aligner. 55. The exposure method according to item 48 of the scope of patent application, wherein the exposure device is a photomask. Align the mask aiigner. 56. The exposure method according to item 48 of the scope of patent application, wherein the liquid tank further includes: a protective cover provided on the top of the liquid tank to seal the liquid tank. 57. The exposure method according to item 48 of the scope of patent application, wherein the liquid tank further includes: a liquid inlet provided at the bottom of the liquid tank; and a liquid outlet provided at the bottom of the liquid tank. 58. The exposure method according to item 48 of the scope of application for a patent, wherein the liquid tank further includes: a return line to circulate the liquid between the liquid tank and the return line (5. 9) The exposure method described in item 58 of the patent, wherein the above 0503-8206TlVf; TSMC2002-0119; Felicia.ptd page 22 559895 6. Scope of patent application The liquid tank further includes: a pump for driving the liquid to circulate between the liquid tank and the return line. 60. The exposure method as described in item 59 of the patent scope of Shenyan, wherein the liquid tank further includes: a filtering device disposed inside the above-mentioned return pipe 'to transition bubbles and impurities generated by the liquid flow. 61. The exposure method according to item 48 of the scope of patent application, wherein the liquid tank further includes: a temperature adjusting device connected to the liquid tank to adjust the temperature of the liquid to maintain the liquid at a value temperature. 62. The exposure method according to item 48 of the scope of the patent application, wherein the substrate is fixed inside the liquid tank by a vacuum system. , 0503-8206TWf; TSMC2002-0119; Felicia.ptd page 23