TWI220536B - Exposure method and apparatus for improving defects formed by proximity print - Google Patents

Abstract

An exposure method and apparatus for improving defects formed by proximity print is disclosed, in which a photo resist layer is formed on a glass, a strip pattern is formed on a photo mask and the photo mask is located on top of the glass with a specific gap. The dynamic exposure method is to make the glass and the photo mask move with respect to each other when exposing the photo resist layer.

Description

1220536 V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a dynamic exposure method and device, and more particularly to a method capable of improving defects caused by proximity exposure (prOximity print). Exposure method and device. [Prior art]

The lithography process can be said to be the key process of the semiconductor process. The purpose of lithography is to make the structure pattern of 5 people on a photomask (ph〇t〇mask), and then transfer the pattern on the photomask to a coated organic photoresist (ph〇t〇resis1 :, pr ) On the glass of the film, after the irradiation and development of light passing through the photomask, the photoresist layer can exhibit the same pattern structure as that on the photomask. The formation of the photomask is to use an electron beam exposure system to make the pattern on the chromium film (graphics of the design circuit) on glass or quartz, and then use the metal chromium film on the photomask to block the light without the metal chromium film. The light will penetrate the glass and reach the organic photoresist. The difference between transparent and opaque light on the photomask can be used to define the exposed and non-exposed areas on the photoresist coating, and then through appropriate development steps, the photomask circuit pattern can be defined.

Photoresist is a kind of photosensitive material, which is made of a mixture of sensitizer (S e n s i t i z e r), resin (Resin) and solvent (Solvent). According to material characteristics, photoresist can be divided into two types: positive photoresist and negative photoresist. After the positive photoresist is irradiated with light, the molecular bonds are cut off, so it is easily soluble in the developing solution. The negative photoresist is the opposite. After being irradiated with light, the molecular bonds will be interactively linked (c r 0 s s — 1 i n k e d), so it is difficult to dissolve in the developer. / Glass exposure in lithography technology depends on whether the mask is connected to the glass

TW1103F (Chimei) .ptd Page 4 1220536 V. Description of the invention (2) The touch knife is exposed by contact print, proximity (, ΓΓχ 1mity Print) exposure and projection (pr〇jrcti〇n print) exposure Wait for a big class. The figure exposed by contact exposure is closest to the pattern on the mask. The ratio of the size of the image on fma to the figure on the mask is 丨: 1, the resolution is not "good, but because the mask and the glass surface are exposed during exposure. With contact, as the number of exposures increases, particles or damage are gradually deposited, and the quality of the transfer pattern is no longer used by large integrated circuit factories. The projection exposure method uses a projector-like method to project the ratio of the size of the I cover on the photomask onto the photoresistor. The advantage is that it is on the glass: ^ The graphic on the mask can be explained by a suitably designed optical system ?: Magnification adjustment, Therefore, the size of the graphic on the photomask can be enlarged and produced :; The circular resolution on the junk field is relatively high, and the size of the graphic can be 'i_ The disadvantage is the optical system used, ff 4 * 4 s, and the contact exposure method Principle: The exposure type is basically "... · < phase r, the figure on the glass and the figure on the reticle. *, But the reticle is not in direct contact with the glass, which avoids the 艏 // near π z analysis projection exposure However, ^ contact exposure does not require the use of expensive optical systems. Therefore, in the balance of resolution and cost, the proximity exposure is a common process. Proximity exposure is commonly used in semiconductor rm contact exposure. Time'—the distance (factory) between the general reticle and the glass, the force is 50 ~ 50 0❹, the best is about 10. Be careful of the photoresist, or the particles brought in when the product is transported, and Make the surface of the reticle correct in the shape of the object. Please refer to Figure i, ^ Shows that the photomask is stained = Do not ring Figure 1220536 5. In the description of the invention (3), a schematic diagram of the pattern transfer that affects the negative photoresistor. = The pattern formed by the slit T when the second narrow is long, and its order is narrow. The slit is contaminated with-the particle mλ line will pass through the slit and reach the photoresist on the base 6. The Renxian line cannot pass through the particle 104. If the coated photoresist is a negative photoresist (MgaUve PR), Partial development will be left after the development, the part without the first line will be washed away after development, and the two positions of the particle 104 are illuminated by the t method to form a small blank area *, this is called White defect (white defect) 11 〇 (as shown on the right side of Figure 1). Please refer to Figure 2, which shows a schematic diagram of the pattern transfer that affects the positive photoresist when the mask is contaminated with foreign objects. "Cover 2 〇2 has a pattern of a plurality of long opening ^ slits, and one of the slits is contaminated with a particle 204. When exposed, light will pass through the slit to reach the photoresist on the substrate, but the light cannot pass through. Particle 2 04. If the coated photoresist is a positive photoresist (p0sitive pR), the part exposed to the light will be washed away after development, and there is no light. Part of it will remain after development, but the photoresist at position 204 relative to the particles is left behind due to inability to illuminate, forming a small protruding area. This is called a black defect 210 (as shown in Figure 2). (Shown on the right). In addition, after using the photomask for a period of time, the light-shielding film such as the metal chromium film may be scratched or detached, so light will penetrate the glass to the photoresist, causing defects similar to the above. Once a defect is found during product inspection, if the size of the defect exceeds the allowable specification, a new photomask needs to be replaced, and this piece of product also needs to be scrapped. However, if the size of the defect is on the edge of the allowable specification or less than the allowable specification, traditional The solution is to remove the photomask for cleaning. However, the cleaning time is at least

TW1103F Emi) .ptd

1220536 V. Description of the invention (4) More than 30 minutes, it is very time-consuming. [Summary of the Invention] In view of this, the object of the present invention is to provide a dynamic exposure method and an exposure device thereof, which can not only improve the defects caused by proximity exposure (proximity pr int), but also save the cost of removing and cleaning the photomask. time. According to a first object of the present invention, a dynamic exposure method is provided to improve defects caused by proximity printing, such as mask pattern defects and mask membrane defects. defect). One of the glasses has a photoresist layer, and a mask has a strip pattern, and the mask is located a certain distance above the glass. The dynamic exposure method is: When the photoresist layer is exposed, the glass and the photomask are moved relative to each other. When the defect to be improved is a mask pattern defect (such as a white defect or a black defect), ', the relative movement direction of the glass and the mask is parallel to the stripe pattern of the stripe pattern' to adhere to the mask The photoresist portion of the foreign object compensates the exposure area. According to the second object of the present invention, a dynamic exposure method is proposed to change the line width of the photoresist after close exposure. One of the 4 glass has a photoresist layer and a photomask. It has a strip-shaped pattern on it, and the mask is ^ {立 U > a ^ 万 —definite distance. The dynamic exposure method is as follows: when the photoresist layer is exposed, the relative movement of the glass and the photomask is relative, and the movement direction is perpendicular to the stripe direction of the stripe to change the line width of the photoresist. According to a third object of the present invention, a proximity exposure device is provided.

TW1103F Emei) .ptd Page 7 1220536 V. Description of the invention (5) tm: Color filter substrate for exposure ', which uses-mask first through 詈 = cymbal substrate to form a pattern with a plurality of long photoresistors When this exposure exposes mi, the photomask and the substrate are moved relative to each other to block the ° area; the photoresist is compensated for the exposure amount to form at least -compensated light for the purposes, features, and advantages of the present invention. Ming such as the "Wente cite a preferred embodiment, and in conjunction with the attached drawings, a detailed description [Implementation] Dynamic exposure method is used at the time '" so that the glass and the mask in the exposure == relative to, for the transfer pattern Or the defect of the light-shielding film of the photomask is compensated. The following is a detailed description with preferred embodiments. ’The embodiment does not limit the scope of the invention to be protected. …, The kite photo is shown in FIG. 3, which shows the intention of the method according to the first embodiment of the present invention. The mask 302 is provided with a plurality of elongated slits, and one of the slits is attached with a foreign object, such as particles 304. Advance = day ^, and quickly cause relative displacement between the photomask 3 02 and the glass. If the shutter time is about 3 seconds, the photomask 30 can be moved upwards within 3 seconds to produce d. During exposure, the light will pass through the slit and reach the light cloth on the substrate 360: the photoresist \ Negative photoresist 308, the transfer pattern generated after development is as shown in Figure 3. The compensation area 3 10 is displayed. Since the photomask 30 moves, the negative photoresist relative to the particle position of 304 can receive at least one-eighth of the exposure energy, so it will not be completely removed after development.

TW1103F (Chimei) .ptd Page 8 1220536 V. Description of the invention (6) The defects of the invention become smaller or even non-existent. In this embodiment, it is a negative-type photoresist material that can generate molecular bonds by selecting the exposure energy, but will not dissolve in the liquid. It is worth noting that the direction of movement at this time should be parallel to the direction of the pattern on the mask. For example, in Fig. 3, the long slit on the photomask 30 is in the X direction, and the moving direction must also be + X or -X direction 'to achieve the purpose of repairing the exposed area. If allowed by the exposure machine, + X and-x can be moved at the same time, which is not limited in the present invention. ^ As for the setting of displacement d, it depends on the allowable range of product specifications. Under normal circumstances, most manufacturers hope to be able to save the products in the specifications. If the maximum diameter of the foreign body is D, the displacement is d. Therefore, it depends on the capability of the specification. Γ previous chapter \ Λ depending on the application situation and machine movement m. It is worth noting that \ 界 用 ’二? The maximum tolerance value is about 15〇 #, which is too large, so as not to make the border of the black matrix (BM) move the rails around. It is not possible to cause problems in the future when two pieces of glass are glued.夕 k first blocks, so that in addition, during relative movement, it can move, but the mask does not move; the base of the loader glass is not restricted in the movement of the base: d cover moves, the base does not, Please refer to FIG. 4 for the hair, which shows the objects depending on the function of the exposure machine. Schematic illustration of the method. The photoresist coated on the exposure plate of the second embodiment of the first embodiment is the same as that of the positive photoresistance m-light method, except that there are a plurality of long slits TW1103F on the base. Ptd $ 9 pages 1220536

And with the pattern light composed in it, ㈣4G2 and glass are quickly produced ^ pair of grains = 4G4 °, the exposure line of Jinshi will pass through the slit to reach t on the substrate, exposure 7, light to grain = position Λ to light The movement of the army 4 ° 2, so that the positive photoresistor at the relative / sub 404 position can be received at least this summer, so it will be completely moved after development. Exposure energy can generate molecular bonds that are broken, and a positive photoresist material dissolved in the developer. The setting of the displacement d 'depends on the tolerance of the product specification. If the maximum diameter of the foreign object is D, displacement will occur. Is d, the difference between the two (D '-d') must be less than the black defect value s allowed by the specification. Therefore, if the black defect value allowed by the specification is 8 〇 # m, the maximum diameter of the foreign body is 2 〇〇 # m, the displacement d 'can be set to 1 2〇 # m. The actual setting value depends on the application conditions and the force of machine movement. At present, the maximum tolerance value of black defects in the industry is about 2 5 〇β m 〇 In the second embodiment, the direction of the relative movement must also be parallel to the pattern direction on the photomask. As for the movement + χ or -The X direction or both directions depends on the capabilities of the exposure machine. In addition, whether the moving object is a photomask or a substrate depends on the function of the exposure machine, which is not limited in the present invention. In the above two embodiments, the photoresist pattern after the transfer is longer than the length of the slit on the photomask. Therefore, if the head and tail sections of the photoresist pattern have an impact on the product, the final required transfer pattern can be used. To modify the picture on the mask

TW1103F (Chimei) .ptd Page 10 1220536 V. Description of Invention (8). For example, reduce the length of the slits in the photomask to match the length of the stripe photoresistor. The dynamic exposure method of the present invention can be used to improve mask pattern defects, such as white defects or black defects caused by foreign matter adhering to the mask pattern, and can also be used to improve the mask light-shielding film. Defect (mask membrane defect). After the photomask is used for a period of time, the upper light-shielding film such as the metal chromium film may be scratched or detached, so light will penetrate the glass to reach the photoresist, causing similar defects as described above. In the present invention, the photomask and the substrate The relative displacement can also be used to compensate the exposure area by 4 °. The principle of compensation is the same as that of the first or second embodiment, and will not be repeated here. In addition, the dynamic exposure method of the present invention can also be applied to change the photoresistance line width (Jine ^ width). Please refer to FIG. 5, which illustrates a schematic diagram of an exposure method according to the present invention. There are multiple long patterns on the photomask 502. During exposure, the photomask 5 ° 2 and glass ^ „are quickly shifted to a vertical direction perpendicular to the pattern on the previous mask. + Γ direction) is moved to produce 'Λmask 502 in 3 To the right within a second (that is, a displacement y is generated. Expose the day guard, assuming that the photoresist applied is a negative photoresist, the soil blocking pattern after development is shown in Figure 5, and the negative 1 In the first resistance 508 transfer, the system chooses to receive two minutes of feed and see the increase of y. This embodiment will not dissolve = visible, liquid negative photoresist material. The knife is linked, and it is important to note that this type of The application is applied to the long photoresistor, and the exposure method that sees the first line is the same, so the corresponding one is a magic mask with a plurality of long shapes.

1220536 V. Description of the invention (9) Pattern composed of slits. After the exposure, the edge of the glass forms a compensation photoresistance area, which is caused by the relative movement with the glass. In summary, the relative movement of the dynamic exposure glass and the photomask of the present invention compensates for the shortcomings of insufficient exposure areas or the disadvantages of too large exposure areas. Among them, when the exposure is insufficient due to foreign matter adhesion, it will cause damage and make the exposure area too large, which will cause a black photoresist on the glass. However, if the foreign matter adheres, 1¾, but if the exposure area is damaged, the exposed area will be damaged. However, the present invention can be used for both white defects and black defects. In addition, in a general exposure process, exposure is performed. That is to say, the substrate must be displaced from the photomask or photomask, re-aligned, and exposed. The traditional process is to solve the alignment and white exposure time, such as white defects or black defects. Compared with this time, the substrate, the photomask, and other processes such as displacement, alignment, and exposure can be rapidly generated. Therefore, it can be seen from the above that the defect of the dynamic exposure daylight mask pattern of the present invention (mask patt stuck in the photomask) The white defects or mask membrane defects caused by the above method can also be used to change some line widths, thereby reducing the number of long photoresistance compensation photoresistance areas on the glass using the exposure method, which is used during exposure. Foreign matter adheres to the mask pattern to compensate for the white defect on the glass caused by the negative photoresist caused by the damaged mask, but if the mask is defective. Conversely, when the positive exposure is insufficient, the black defect will be too large. White defects. Exposure compensation. The process of stepwise alignment, exposure, etc. of the substrate is used. If the problem is 'then need to go through twice, the present invention moves in one exposure' without having to go through again. The advantage of moving can save time. The light method can improve the proximity exposure, such as the trapping of foreign matter, and the improvement of the light-shielding film defect becomes smaller or does not exist. The number of discarded substrates, so

1220536 V. Description of the invention (ίο) Has the advantage of reducing production costs. In summary, although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Retouching, so the scope of protection of the present invention shall be determined by the scope of the attached patent application.

TW1103F (Chimei) .ptd Page 13 1220536 Brief description of the drawings [Simplified description of the drawings] Figure 1 shows the schematic diagram of the pattern transfer that affects the negative photoresist when the mask is contaminated with foreign objects; Figure 2 shows the mask contamination In the case of foreign matter, the pattern transfer of the positive photoresist is not intended. FIG. 3 is a schematic diagram of the exposure method according to the first embodiment of the present invention. FIG. 4 is a schematic diagram of the exposure method according to the second embodiment of the present invention. And FIG. 5 is a schematic diagram of an exposure method according to a third embodiment of the present invention. Description of figure numbers 102, 202, 3 02, 402, 502 ······················································· 208, 408 · Positive photoresistor 11 0: White defect φ 2 1 0: Black defect 3 1 0: Compensation area 41 0: Tiny black defect

TW1103F (Chi Mei) .ptd Page 14

Claims (1)

1220536 6. Scope of Patent Application1. A dynamic exposure method is used to improve the mask pattern defect caused by proximity printing. One substrate has a photoresist layer and one photoresist layer. The mask has a strip pattern, the mask is located at a certain distance above the substrate, and a foreign object is adhered to the strip pattern. The method includes the following steps: When exposing the photoresist layer, the The substrate and the photomask are relatively moved, and the moving direction is parallel to the stripe direction of the stripe pattern, so as to compensate the exposure area of the photoresist layer on the photoresist layer relative to the foreign object. 2. The dynamic exposure method as described in item 1 of the scope of patent application, wherein the photoresist layer is a negative photoresist (negative PR), which can improve a white defect caused by proximity exposure. 3. The dynamic exposure method as described in item 1 of the scope of patent application, wherein the photoresist layer is a positive photoresist (positive PR), which can improve a black defect caused by proximity exposure. 4 · A dynamic exposure method is used to improve the mask film defect caused by proximity exposure. Among them, there is a photoresist layer on the substrate, and a mask on one of the masks with a special pattern. (protective membrane), the photomask is located at a certain distance above the substrate, and the light shielding film is damaged to cause at least one light-transmitting area at the photomask. The exposure method includes the following steps: when the photoresist layer is exposed, The substrate and the photomask are caused to move relative to each other, so that the photoresist portion of the photoresist layer with respect to the light transmitting area is compensated for the exposure area. T TW1103F Yimei) .ptd Page 15 1220536 VI. Application for Patent Scope 5. A dynamic exposure method is used to change the line width of the proximity resistance (i Α ^ μ. 丄 ιατη) on one of the substrates There is a photoresist layer, and a strip pattern along a first direction. The photomask is located a certain distance above the substrate. The method includes the following steps: ^ exposing the photoresist layer At this time, the substrate and the photomask are caused to move in a vertical direction in the 4th-direction to change the line I forming the photoresist. 1. According to the dynamic exposure method described in item 5 of the scope of patent application, this layer is a negative photoresist (negative PR), which can increase the green color of the photoresist. 7. The dynamic exposure method as described in item 5 of the scope of the patent application, the ΐ = layer in the bean is a Positive Photoresist (Positive PR), which can reduce the formation of photoresist. 8 · A dynamic exposure method, which is used to improve Defects caused by proximity printing, in which a substrate has a photoresist layer and a photomask has a strip pattern (striP pattern), and the photomask is located a certain distance above the substrate. This method include: When exposing the photoresist layer, the substrate and the photomask are brought into phase.) 9. The dynamic exposure method as described in item 8 of the scope of patent application, in which the movement direction of 4f and the relative movement of the photomask and The stripe pattern = direction, 4 Yu, mask pattern defects on the photoresist layer formed by the adhesion of a stripe to the stripe pattern (mask pattern) TW1103F (Chi Mei) .ptd 1220536 6. The scope of the patent application (defect) 〇 This: The dynamic exposure method described in item 9 of the ΐΠΠΐ Wai, the photoresist layer 1 bis negative resistance (negative pR), which can compensate the white defect caused (white defect) ). φIn the private exposure method described in item 10 of the scope of patent application, one pass: two. : The diameter is D 'The relative distance is s' (DS) is not exceeding the resistance. Please use the dynamic exposure method described in item 9 of the patent scope, which ==: = ::> ritivePR), can compensate the cause Black defect. The dynamic exposure method as described in item 12 of the patent scope in the above paragraph, the diameter of the neutral or foreign object is]), relative to the order and miscellaneous ★ 〇 / times have about 250. The relative movement distance is S. (DS) is not the dynamic exposure method described in item 8 of the middle mask. I: 辄 工 ## Shielding (PrôteCtiVe membrane), and the The relative movement of the base cover can compensate for the defect of the reticle's light-shielding film (mas "embrane deffct; the film is damaged.) 15. The relative movement of the substrate and the photomask as described in item 8 of the scope of patent application ~ + / 'Eight cases have a stripe direction that is perpendicular to change the direction of movement and the line width. The line width of the photoresistor after close-contact exposure is 16 · A color filter substrate, which uses a Shuicheng has a plurality of elongated photoresist patterns, where = = a pattern composed of long slits in the shape of a soil plate, and 1 in _ μ is first covered with a plurality of thousands, and the nail slit is contaminated with a particle, and TW1103F (Chimei) .ptd Page 17 1220536 VI. Scope of patent application The positions of the strips of the elongated light-replenishing photoresistance area of the substrate 1 7 · As for the patent application, the stripe photoresistors are inch series It does not exceed about 150 mm. 1 8 · If you apply for a patent, where the long photoresistors are not more than about 2 50 0 m. 19 · A close-type exposure plate is used for exposure, in which a plurality of elongated photoresistors are used to compensate the exposure amount of the photomask and the substrate, and the shape of the photomask is such that the photomask and the substrate move The direction of the stripes is parallel to carry out 21. If a light-shielding and light-shielding film on the photomask is damaged to cause exposure at least, the photoresist layer can be made opposite to the transparence. 22. For example, in the patent application, the photomask and the substrate are moved with a photomask to make the color filter substrate to form a light device, which can be used to form at least one compensation photoresistance area for the elongated photoresistors during exposure. . The close-type exposure device is described. In the pattern of the long photoresist patterns, one of the photoresist of a relatively moving substrate and the photoresistive region is a compensation photoresistive region, and the positions of the particles correspond. . The color filter substrate described in item 16 is a negative type photoresist, and the size of the compensation photoresistance region is the color filter substrate described in item 16 is a positive type photoresist, and the compensation light is The ruler light device in the blocking area is used to compensate the exposure direction of a color filter and the direction of movement of the 19th item of the light film base. The near-type exposure device described in item 19, a protective membrane, and the light-transmitting area is at the photomask, the exposure mask performs a relative movement, so that the limited part of the exposure amount to make up the 19th The proximity exposure device described in the item 'moving direction is related to the pattern of the long photoresist TW11CBF) .ptd Page 18 1220536 6. Scope of patent application Stripe direction is vertical 'to change the line width of photoresist after exposure. 23. A method for compensating an exposed area, wherein a substrate has a photoresist layer and a mask has a mask pattern on the substrate. The mask has a distance from the substrate. The method includes the following steps: When the photoresist layer is exposed, the substrate and the photomask are moved relative to each other to compensate the photoresist on the photoresist layer relative to the photoresist pattern portion. 24. The exposure area compensator according to item 23 of the scope of patent application, wherein the separation distance is about 50 ~ 50 0 # m. 25. The exposure area compensator as described in item 23 of the scope of the patent application, wherein the separation distance is approximately j 〇〜3 〇 〇 # m. 2 6 · The exposure area compensator as described in item 23 of the scope of the patent application, wherein the mask pattern portion is contaminated by a foreign object, resulting in insufficient exposure area. 27. The exposure area compensator described in item 26 of the scope of the patent application is used to compensate a white defect caused by exposure. The photoresist layer is a negative plastic photoresist (negatiVe pr). 28. The exposure area compensation method described in item 26 of the scope of patent application is used to compensate a black defect (b 1 ack defect) caused during exposure, wherein the photoresist layer is a positive pr ). 29. The exposure area compensation method as described in item 23 of the scope of patent application ', wherein the mask pattern portion is a damaged mask and the exposed area is too large. 3 0 · Exposure area compensation method as described in item 29 of the scope of patent application Page 19 lima TW1103F Yimei) .ptd 1220536 VI. Application scope of patents-~~ ______ method, which is used to make up,. Defect), among them a black defect caused by light (black 31 The Kui photoresistor layer is a negative photoresistance (negative PR) method. It is used to compensate for the exposure area compensation effect described in Item 29 of the Ili range), which is a white defect caused by light. (White 32 · Ru Shen ^ Photoresistor> The layer is a positive photoresistor (positive pR). This method is used to complement: 4-member side mask pattern of the exposure area compensator described in item 23 of the Xi range. The line width of the (mask pattern). ° The exposure area compensation method described in item 32 of the scope of patent application ^ 2 The insufficient line width caused by the exposure compensation, wherein the photoresist layer is a negative photoresist (negative PR ). 34. The exposure area compensation method described in Item 32 of the scope of patent application is used to compensate for the excessive line width caused by exposure. The photoresist layer is a positive photoresist (positive PR). ㈢ 35 · A color filter substrate using a photomask to form the substrate with a plurality of elongated photoresists Wherein, the photomask has a pattern composed of a plurality of elongated slits, and the edges of the elongated photoresistors of the substrate are a compensation photoresistance region, and the compensation photoresistance region uses the light during proximity exposure. The cover is moved relative to the substrate. TW1103F Emi) .ptd Page 20