KR20070038706A - Apparatus for cleaning a reticle and apparatus for exposing a substrate having the same - Google Patents

Abstract

In the reticle cleaning apparatus, the inspection unit acquires the positional information of the foreign substances present on the reticle. The cleaning unit removes the foreign matters by sequentially spraying the cleaning gas on the respective foreign matters using the location information of the foreign matters. Therefore, the reticle cleaning process for removing the foreign matters can be efficiently performed by spraying the cleaning gas concentrated on the foreign matters present on the reticle.

Description

Reticle cleaning apparatus and substrate exposure apparatus having the same {Apparatus for cleaning a reticle and apparatus for exposing a substrate having the same}

1 is a schematic diagram illustrating a reticle cleaning apparatus according to an embodiment of the present invention.

2 is a schematic diagram illustrating a reticle.

FIG. 3 is a schematic diagram illustrating a substrate exposure apparatus having the reticle cleaning apparatus illustrated in FIG. 1.

Explanation of symbols on the main parts of the drawings

100: cleaning unit 112: foreign matter

120: drive unit 122: chuck

130: cleaning gas supply unit 132: cleaning tube

134: cleaning gas line 136: cleaning gas tank

140: exhaust part 142: exhaust tube

144: exhaust line 146: pump

150: inspection unit 160: robot arm

170: storage unit 200: exposure unit

R: reticle P: pellicle

The present invention relates to a reticle cleaning apparatus and a substrate exposure apparatus having the same. More particularly, the present invention relates to a reticle cleaning apparatus for removing foreign substances present on the reticle using a cleaning gas and a semiconductor substrate exposure apparatus having the same.

In general, a semiconductor device includes a Fab process for forming an electrical circuit on a silicon wafer used as a semiconductor substrate, and an electrical die sorting (EDS) process for inspecting electrical characteristics of the semiconductor devices formed in the fab process. Each of the semiconductor devices is manufactured through a package assembly process for encapsulating and individualizing the semiconductor devices.

The fab process includes a deposition process for forming a film on a wafer, a chemical mechanical polishing process for planarizing the film, a photolithography process for forming a photoresist pattern on the film, and the photoresist pattern using the photoresist pattern. An etching process for forming the film into a pattern having electrical characteristics, an ion implantation process for implanting ions into a predetermined region of the wafer, a cleaning process for removing impurities on the wafer, and inspection of defects in the film or pattern Inspection process, and the like.

The photolithography process includes a coating process for forming a photoresist composition layer on a silicon wafer, a bake process for curing the photoresist composition layer to form a photoresist film, and a reticle pattern of the photoresist film. And a developing process for forming the transferred reticle pattern into a photoresist pattern.

Here, the reticle used in the exposure process has a very flat plate shape and has a projection pattern corresponding to the image to be transferred onto a plurality of regions set on the wafer. The reticle is generally made of quartz, and the pattern image of the reticle may be formed to be smaller than or the same as the image transferred onto the wafer. Typical transcription magnifications are 1, 5 or 10 times.

However, when contaminants such as particles are present on the reticle, poor patterns may be formed on the wafer due to the contaminants. Since the semiconductor device formed on the wafer has a high incidence of defects, it is preferable to be reprocessed or discarded.

Typically, dozens of reticles with different projection patterns are used to complete a semiconductor device. Accordingly, the reticles are stored in a receptacle library, and reticles necessary for each exposure process are selected and loaded into the exposure apparatus. As such, the reticle is likely to be exposed by particles or contaminants contained in air or the like.

To this end, the exposure apparatus is provided with an inspection unit for inspecting the contamination level. The inspection unit detects particles present on the reticle. If the particles are found to be above a predetermined range, there is a difficulty in stopping the exposure process and manually removing the foreign objects while the operator visually checks the foreign substances. This results in a loss of manpower and an economic loss of stopping the exposure process until the foreign matters are removed.

Therefore, there is a need for the development of an improved exposure apparatus that can suppress the time loss of the exposure process by employing the apparatus in addition to the apparatus capable of automatically cleaning contaminated reticles.

A first object of the present invention for solving the above problems is to provide a reticle cleaning device that can effectively remove the foreign substances present on the reticle.

In addition, a second object of the present invention is to provide an exposure apparatus capable of reducing the time loss required for the reticle cleaning process and improving the reliability of the exposure process by providing the reticle cleaning apparatus.

Reticle cleaning apparatus according to an aspect of the present invention for achieving the first object, by using the inspection unit for obtaining the location information of the foreign matter present on the reticle, and the location information of the foreign matter, the respective foreign matter And a cleaning unit for removing the foreign matters by sequentially spraying the cleaning gas onto the field.

According to one embodiment of the invention, the cleaning unit comprises a chamber for providing a closed space for performing the reticle cleaning process, a cleaning gas supply for injecting a cleaning gas onto the reticle, the inside of the chamber A driving unit for supporting the reticle and moving the reticle so that the foreign matter is positioned adjacent to the cleaning gas supply unit according to the positional information of the foreign matter, and the gas remaining in the chamber and the exhaust for discharging the foreign matter removed from the reticle Contains wealth.

The cleaning gas supply unit may include a cleaning tube that injects the cleaning gas at an angle of about 40 to 50 ° with respect to the front or rear surface of the reticle on the reticle supported by the driving unit.

A substrate exposure apparatus according to another aspect of the present invention for achieving the second object, the inspection unit for obtaining the position information of the foreign matter present on the reticle, and the respective foreign matters using the position information of the foreign matter A cleaning unit for removing the foreign matters by sequentially spraying a cleaning gas on the surface, and a reticle inspected by the inspection unit or a reticle cleaned by the cleaning unit for performing an exposure process on a substrate to be processed. And an exposure unit.

According to the above, by automatically removing the foreign matters by using the position information (coordinates) of the foreign matter on the reticle, it is possible to reduce the manpower loss and time loss due to the manual removal of the foreign matter on the reticle by the operator by the naked eye. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments and may be implemented in other forms. The embodiments introduced herein are provided to make the disclosure more complete and to fully convey the spirit and features of the invention to those skilled in the art. In the drawings, the thickness of each device or film (layer) and regions has been exaggerated for clarity of the invention, and each device may have various additional devices not described herein.

1 is a schematic diagram illustrating a reticle cleaning apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the reticle cleaning apparatus includes a test unit 150 for detecting a foreign matter present on the reticle R and a cleaning unit 100 for removing the foreign matter.

Prior to describing the reticle cleaning apparatus, a reticle R used in a conventional semiconductor exposure process (see FIG. 2), the reticle R 10 transmits light provided by a light source of the exposure apparatus. It has a plate 12 made of a material that can be made. For example, the plate 12 is made of glass. The plate 12 is formed with an exposure pattern 14 for selectively projecting or blocking the light provided to the plate. In addition, on the plate 12 on which the exposure pattern 14 is formed, a thin film collectively referred to as a pellicle 16 for protecting the exposure pattern is provided so that the exposure pattern is not contaminated by foreign matter such as dust. The pellicle 16 may be fixed to the plate 12 by the pellicle frame 18.

Referring back to FIG. 1, the inspection unit 150 of the reticle cleaning apparatus uses a conventional IRIS system (Integrated Reticle Inspection System) for detecting surface defects of the reticle (R). That is, the inspection system may inspect both the front and rear surfaces of the reticle R 10, that is, the pellicle surface 10a and the glass surface 10b. The inspection unit 150 may include a monitor (not shown) that displays the positions of the foreign substances present on the surfaces. Through the surface defect inspection, it is possible to determine the size and number of foreign matters in addition to the locations of the foreign matters.

The cleaning unit 100 connected to the inspection unit 150 includes a chamber 110 for performing the reticle R cleaning process, a driver 120 for supporting and moving the reticle R, and the reticle R. ) And a cleaning gas supply unit 130 and an exhaust unit 140 for injecting the cleaning gas onto the exhaust gas.

The chamber 110 has a gate (not shown) for accommodating the reticle R which has been inspected in the inspection unit 150 at one side thereof. The gate blocks the outside air after the reticle R is loaded to provide a closed cleaning space.

The driving unit 120 may include a chuck 122 for supporting the reticle R and a driving unit 120 for moving the chuck 122 such that the reticle R is horizontal. For example, the chuck 122 may hold the pellicle surface 10a or the glass surface 10b of the reticle R using a vacuum force. The driving unit 120 is a multi-axis rectangular coordinate robot for moving the reticle R supported by the chuck 122 in the horizontal direction according to the position information (coordinate) of the foreign matters obtained by the inspection unit 150. It may include. Here, the reticle R is moved so that the coordinates of the foreign matter to be removed coincide with the reference coordinates at which the cleaning gas injected from the cleaning tubes 132 and 132 to be described below arrives.

The cleaning gas supply unit 130 may include a cleaning tube 132 for injecting the cleaning gas at a high pressure, a cleaning gas tank 136 for supplying the cleaning gas, and a connection between the cleaning tube 132 and the cleaning gas tank 136. A cleaning gas line 134 is provided.

In order to more effectively remove the foreign matter adsorbed on the reticle R, the cleaning tube 132 has a reticle R supported by the chuck 122 in the direction of the cleaning gas injected from the cleaning tube 132. It is preferable to have angle (theta) of about 40-50 degrees with respect to the pellicle surface 10a (or glass surface 10b) of (). More preferably, the jetting direction of the cleaning gas has an angle θ of about 45 ° with respect to the plane of the reticle R.

In addition, the other side of the chamber 110 is provided with an exhaust unit 140 for discharging the gas remaining in the chamber 110 and the foreign matter removed from the reticle (R). The exhaust unit 140 includes an exhaust tube 142, a pump 146, and an exhaust line 144 provided in the chamber 110. For example, the exhaust tube 142 may be disposed to face the cleaning tube 132 of the cleaning supply part so that the cleaning gas may be exhausted immediately after being injected onto the reticle R.

Hereinafter, the foreign material removal process using the reticle cleaning device will be briefly described.

First, the reticle R is loaded into the inspection unit 150 and the surface defect inspection process is performed. As a result of the inspection, the position information of the foreign substances existing on the reticle R is input to the driving unit 120 of the cleaning unit 100 as reticle coordinates. For example, first to third particles having first to third coordinates, respectively, are detected on the pellicle surface 10a of the reticle R, and fourth and third particles are formed on the glass surface 10b of the reticle R. Assume that the fourth and fifth particles having five coordinates, respectively, are detected.

Then, by using a conveying means such as a robot arm (reference numeral 160 of FIG. 2), the reticle R on which the inspection is completed is placed on the chuck 122 disposed inside the chamber 110 of the cleaning unit 100. The pellicle face is loaded upward. The driving unit 120 matches the coordinates (reticle coordinates) of the foreign matters with the reference coordinates (driving unit coordinates) at which the cleaning gas arrives in order to sequentially remove the respective foreign substances. For example, after matching the first coordinates with the reference coordinates to remove the first foreign matters on the pellicle surface, the cleaning agent is sprayed with a gas to remove the first particles and at the same time through the exhaust pipe. To the outside of the chamber 110. The same method may be applied to the second and third foreign matters to remove all foreign matters present on the pellicle surface.

Subsequently, the reticle R may be loaded on the chuck 122 so that the glass surface of the reticle R faces upward, and the third and fourth foreign matters may be removed in the same manner as described above to complete the reticle R cleaning process. .

FIG. 2 is a schematic diagram illustrating a substrate exposure apparatus having the reticle cleaning apparatus illustrated in FIG. 1.

Referring to FIG. 2, a photoresist (not shown) is coated on the silicon substrate W, and the photoresist coating layer is formed into a photoresist pattern through an exposure process and a developing process. The photoresist film is formed on the substrate W through a photoresist composition coating process and a soft bake process, and the photoresist pattern formed through the exposure process and the development process may be used as an etching mask or an ion implantation mask.

A plurality of shot regions are set on the substrate W, and each shot region includes at least one die region. The size of the die region may vary according to the type of semiconductor device desired, and the size of each shot region and the number of shot regions may be determined according to the size of the die region.

The illustrated substrate exposure apparatus includes an accommodation unit 170 for largely storing a plurality of reticles R, an exposure unit 200 for performing an exposure process on a substrate W to be processed using the reticle R, Inspection unit 150 for detecting a foreign matter present on the reticle (R), a cleaning unit for cleaning the reticle (R) when the foreign matter is detected by the inspection unit 150 more than a predetermined range ( 100).

The exposure unit 200 includes a light source 210 for generating illumination light, a reticle R having a first image pattern (or projection pattern) corresponding to the photoresist pattern, and light having a light transmission region having a rectangular ribbon shape. A reticle assembly (not shown) comprising a transmissive member (not shown) and a reticle stage 235 for supporting the reticle R and the light transmitting member, an illumination member for illuminating the reticle R with the illumination light ( 220, a projection member 240 for projecting the illumination light (transparent light) passed through the reticle R onto the substrate W, a substrate stage 250 for supporting the substrate W, and the like. Include.

The first image pattern of the reticle R is similar to an image to be transferred onto the substrate W, and the image corresponds to the desired photoresist pattern. That is, the illumination light illuminated on the reticle R is formed as projection light including image information through the reticle R. The light transmitting member is disposed to be adjacent to one side of the reticle R, and has a second image pattern for forming the illumination light as a scanning light having a cross-section of a rectangular ribbon. The second image pattern has a quadrangular ring formation including a light transmission region of the rectangular ribbon shape, and the light transmission member is used as an auxiliary reticle for exposing die regions bordering an edge portion of the substrate (W). . An excimer laser that emits an excimer laser beam may be used as the light source 210. The light source 210 is connected to the lighting member 220 through a beam matching unit (BMU) (not shown). The lighting member 220 transmits the illumination light generated from the light source 210 onto the reticle R or the light transmitting member, and is illuminated onto the reticle R or the light transmitting member through the lighting member 220. The illuminated light has a cross section of a rectangular ribbon shape.

Although not shown, the lighting member 220 includes an illumination system housing, a variable beam attenuator, a beam shaping optical system, and a fly for sealing the interior from outside air. Fly-eye lens system, vibrating mirror, condenser lens system, aperture stop plate, beam splitter, relay lens , A reticle blind mechanism, a plurality of mirrors, and the like. In addition, the substrate exposure apparatus further includes driving units (not shown) for moving the reticle stage 235 and the substrate stage 250 in the horizontal direction.

Additional details of the above components are similar to those already known in the art (US Patent No. 6,331,885, US Patent No. 6,538,719), and thus will be omitted.

The reticle inspection unit 150 is disposed on one side of the exposure unit 200. The inspection unit 150 is a place where a reticle inspection process is performed to prevent defects in the exposure process, and before the reticle R enters the reticle stage 235 of the exposure unit 200, the reticle R Detect foreign substances present in the phase. The inspection is performed by an IRIS system using a laser or the like as described above.

When the inspection detects that the number and size of foreign substances P on the reticle R exceed a predetermined threshold value, the reticle R does not proceed to the exposure unit 200 for an exposure process and the cleaning unit 100 ) Is a cleaning process for the reticle (R). The series of processes leading to the foreign matter inspection process, the cleaning process, the re-inspection process, and the exposure process is preferably performed automatically by an electromechanical system provided in the substrate exposure apparatus. In addition, since the apparatus for cleaning the reticle R is conventionally disposed separately from the substrate exposure apparatus, the time loss required for the cleaning is large, but according to the substrate exposure apparatus according to the present embodiment, the reticle cleaning apparatus Since 100 is integrally provided in the substrate exposure apparatus, time loss required for the exposure process due to the cleaning can be reduced.

The cleaning unit 100 includes a chamber 110, a driving unit 120, a cleaning gas supply unit 130, and an exhaust unit 140. Since the cleaning unit 100 including the components as described above has the same configuration and function as those described above with reference to FIG. 1, further detailed description thereof will be omitted. Here, the cleaning unit 100 is disposed adjacent to the inspection unit 200 to minimize the loss of time required for the exposure process.

The accommodating unit 170 provides a space for accommodating the reticles R having various patterns necessary for performing a series of exposure processes required to complete the semiconductor device in a multilayer manner. Therefore, when the reticle R is selected from the storage unit 170 according to an exposure process, the reticle R is cleaned in the cleaning unit 100, and the cleaned reticle R is inspected. The unit 150 may be loaded into the exposure unit 200. Here, the robot arm 160 for transferring the reticle (R) between the storage unit 170 and the cleaning unit 100 may be provided. Specifically, the robot arm 160 includes a chuck 162 for holding the reticle R, and a driver 164 for driving the chuck 162. Here, the driving unit 164 uses a multi-axis robot including a rotational drive for mounting the reticle (R) on the stage 110 in the chamber 120 in the vertical direction.

As described above, the substrate exposure apparatus according to the present invention is required for manual cleaning by replacing the reticle by the inspection process and replacing the reticle or by using a cleaning apparatus disposed separately outside the substrate exposure apparatus. Time loss can be minimized.

According to the present invention as described above, the reticle cleaning device to check the foreign matter present on the reticle to determine the coordinates of the foreign matter, it is possible to more effectively clean the reticle by spraying the cleaning gas concentrated on the coordinates. Therefore, the reliability of an exposure process can be improved.

In addition, the substrate exposure apparatus including the reticle cleaning apparatus can reduce the time loss required to separately clean the reticle, thereby improving throughput of the exposure process.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (4)

An inspection unit for obtaining location information of foreign objects present on the reticle; And And a cleaning unit for removing the foreign substances by sequentially spraying a cleaning gas on the respective foreign substances using the positional information of the foreign substances. The method of claim 1, wherein the cleaning unit, A chamber for providing an enclosed space for performing the reticle cleaning process; A cleaning gas supply unit for injecting a cleaning gas onto the reticle; A driving unit for supporting the reticle in the chamber and moving the reticle so that the foreign matter is located adjacent to the cleaning gas supply unit according to the positional information of the foreign matter; And And an exhaust unit for discharging the gas remaining in the chamber and the foreign matter removed from the reticle. The cleaning gas supply unit of claim 2, wherein the cleaning gas supply unit comprises a nozzle for injecting the cleaning gas at an angle of about 40 to 50 ° with respect to the front or rear surface of the reticle on the reticle supported by the driving unit. Reticle cleaning device. An inspection unit for obtaining location information of foreign objects present on the reticle; A cleaning unit for removing the foreign matters by sequentially spraying a cleaning gas on the respective foreign matters using the positional information of the foreign matters; And And an exposure unit for performing an exposure process on the substrate to be processed using the reticle inspected by the inspection unit or the reticle cleaned by the cleaning unit.

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