JP2003050468A - Exposure system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure system capable of achieving relative positioning of a support frame and a photomask with a high degree of precision as an exposure system for photolithography for forming the pattern of a large- sized photomask as a latent image in a photosensitive material disposed on the surface of a substrate for working by irradiating the photomask from the rear face side with no formed pattern after the photomask is erected in a nearly vertical direction and attached to a support frame. SOLUTION: An attraction part for fixing a photomask is disposed on a support frame along the frame shape over the whole circumference of the frame, and a photomask is attracted and fixed over the whole periphery by the attraction part. The attraction part comprises flat platelike packing, the attraction face that attracts the photomask is flat and attraction holes for evacuation are pierced in the attraction part up to the attraction face over the whole circumference of the support frame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized photomask, which is mounted in a support frame while standing in a substantially vertical direction.
For photolithography for exposing from the back surface side where the pattern of the photomask is not formed and exposing the pattern of the photomask as a latent image on the photosensitive material provided on the front surface of the processing base material. The present invention relates to an exposure apparatus, and more particularly to an exposure apparatus for plate making in a photo-etching process step in which the positional accuracy of a photomask with respect to a support frame can be determined well.

[0002]

2. Description of the Related Art In recent years, shadow masks for color TVs (CRTs) have been mass-produced with an increase in the amount of use, and depending on the purpose of use, higher definition, larger size, etc. are required. Such a shadow mask is generally produced in an integrated line in which a band-shaped metal plate material is used as a material and etching is performed by a photoetching method. Briefly, while moving the strip-shaped metal plate material continuously or intermittently, usually, a plate making process is performed, and etching resistant resist images are formed on both sides of the plate-shaped metal plate material, and the strip-shaped metal plate material is used as an etching mask. An etching step for etching is performed so that the outer peripheral portion of the product portion of each shadow mask is held by a strip-shaped metal plate material, and
The outer shape was processed with the shadow mask facing the strip-shaped metal plate material. Then, after that, a trimming process for separating each shadow mask is performed to obtain a target shadow mask.

In the plate-making process in the shadow mask production line, a strip-shaped metal plate material having a photosensitive resist film applied and formed on both surfaces thereof is intermittently moved in a substantially stretched state, and is stopped when stopped. In the photosensitive resist film on both sides of the metal plate material, a pair of photomasks formed of a large-sized glass dry plate, are aligned so as to face each other, and each is adhered from both sides of the strip-shaped metal plate material. In this state, an exposure method has been adopted in which the photosensitive resist films on both sides of the metal plate material are exposed through the respective photomasks to form a latent image. And after exposure, develop,
An etching resistant resist image was formed.

Conventionally, for the exposure in the plate making process, an exposure apparatus for photolithography of a type in which a large-sized photomask is mounted on a supporting frame and the exposure is performed from the back surface side on which the pattern of the photomask is not formed is provided. Was used. In this exposure apparatus, a photomask is attached to a support frame in a substantially vertical direction, and a packing 25 is provided along the frame on the support frame, a part of which is shown in FIG.
A groove-shaped suction portion formed by 0, 257 is provided, and vertical positioning pins for determining the vertical position of the photomask correspond to the lower side of the support frame and the lower side of the photomask. And two horizontal positions for positioning the photomask in the horizontal direction at a position corresponding to the side surface of the photomask on one side in the horizontal direction of the support frame. There was one pin. When the photomask is mounted on the support frame, the photomask is manually pressed against the positioning pins, as shown in FIG.
The photomask was adsorbed by the groove-shaped adsorbing portion and fixed to the support frame.

However, in the case of the exposure apparatus having the support frame as described above, when the photomask is adsorbed, the packings (packings 250 and 257 shown in FIG. 5B) are deformed non-uniformly, and the restoring force of the packings. When the relative position between the support frame and the photomask gradually changes and the photosensitive resist film on both sides of the metal plate is exposed from both sides, the position of the pair of photomasks on the front and back of the metal plate is changed. The alignment accuracy sometimes deteriorated. For this reason, with increasing demand for higher definition and larger size of shadow masks, recently, in exposure for shadow mask manufacturing, the relative position between the support frame and the photomask described above has been The deterioration of the alignment accuracy of the pair of photomasks on the front and back of the metal plate material has been a problem due to the gradual change.

[0006]

As described above, when exposing the photosensitive resist films on both sides of the metal plate material from both sides like the exposure in the plate making process of the shadow mask, a large size photomask is used. While mounted on the support frame, exposure is performed from both sides of the metal plate material by exposing from the back side where the pattern of the photomask is not formed, but recently, the relative position between the support frame and the photomask is gradually increasing. The deterioration of the alignment accuracy of the pair of photomasks on the front and back of the metal plate material caused by the change has become a problem, and it has been demanded to cope with it. The present invention corresponds to this, and in a state in which a large-sized photomask is set up in a substantially vertical direction and mounted on a support frame, exposure is performed from the back surface side on which the pattern of the photomask is not formed, and the photomask An exposure device for photolithography for exposing and forming a pattern as a latent image on a photosensitive material provided on a surface portion of a processing substrate,
It is an object of the present invention to provide an exposure apparatus for photolithography in which the relative positional change between the support frame and the photomask is extremely small. Specifically, it is intended to provide an exposure apparatus for producing a shadow mask, which is capable of performing exposure from both sides of a metal plate material, which can cope with the recent increase in definition and size of shadow masks. is there.

[0007]

In the exposure apparatus of the present invention, a large-sized photomask is set up in a substantially vertical direction and mounted on a support frame, and exposure is performed from the back surface side where the pattern of the photomask is not formed. Is an exposure device for photolithography for exposing and forming the pattern of the photomask on the photosensitive material provided on the surface of the processing base material as a latent image. The adsorption part for fixing is provided along the entire frame shape along the frame shape, and the photomask is adsorbed and fixed on the entire periphery of the frame by the adsorption part. The adsorption surface for adsorbing the photomask is a flat surface, and the adsorption portion is provided with adsorption holes for evacuation reaching the adsorption surface all around the support frame. Characterized by Than it is. And, in the above, the suction holes for vacuum suction provided on the suction surface are:
It is characterized in that a large number of small holes are provided all around the support frame. Further, in the above description, the adsorption surface of the adsorption portion for adsorbing the photomask is made of a rubber material having a high coefficient of static friction. Further, in the above, using a photomask held by a supporting frame for each of the photosensitive materials provided on the front and back surfaces of the processing base material, from the back surface side of the photomask, the photomask and the processing base material, respectively. A double-sided exposure device used in a plate making process for producing a shadow mask, which forms a latent image by exposing a photosensitive material disposed on the surface of a material in vacuum and exposing the material substantially at the same time. To do. In addition, here, "large size photo mask"
Is a photomask of such a size that it is burdensome to carry by hand, usually a photomask having a size of 24 inches in width and 32 inches in height or more.

[0008]

With the exposure apparatus of the present invention having such a structure, the back side of the photomask on which the pattern is not formed is in a state in which a large-sized photomask is set up in a substantially vertical direction and mounted on the support frame. An exposure device for photolithography for exposing and exposing a pattern of a photomask as a latent image on a photosensitive material provided on a surface portion of a substrate for processing, which comprises a support frame and a photomask. It is possible to provide an exposure apparatus for photolithography, which has an extremely small change in position relative to. Specifically, the support frame is provided with an adsorption portion for fixing the photomask along the entire frame circumference along the frame shape, and the adsorption portion adsorbs the photomask over the entire periphery. For fixing, the suction part is made of a flat plate-shaped packing,
The adsorption surface that adsorbs the photomask is flat, and the adsorption portion is provided with adsorption holes for vacuuming that reach the adsorption surface over the entire circumference of the support frame.
You have achieved this. That is, the suction portion is made of a flat plate-like packing, and the suction surface for sucking the photomask is made flat so that the suction portion can be uniformly deformed at each position when the photomask is sucked. ,result,
It is possible to suppress the relative positional change between the support frame and the photomask due to the non-uniform deformation of the suction portion at each position. Further, since the suction holes for vacuum suction provided on the suction surface are a large number of small holes arranged over the entire circumference of the support frame, the hole portion can be manufactured by using a cutting die. It is supposed to be possible. Further, when the suction surface of the suction portion for sucking the photomask is made of a rubber material having a high static friction coefficient, the relative positional change between the support frame and the photomask can be reliably reduced.

An exposure apparatus uses a photomask held by a support frame for each of the photosensitive materials provided on the front and back surfaces of a processing substrate, and the photomask and the processing are performed from the back surface side of the photomask. In the case of a double-sided exposure device used in a plate making process for producing a shadow mask, which forms a latent image by exposing a photosensitive material provided on the surface portion of a substrate for vacuum to a vacuum and exposing at substantially the same time. Is particularly effective. still,
The double-sided exposure apparatus used in the plate-making process for producing the shadow mask is usually one in each of the two lower sides of the support frame so as to be substantially horizontal to each other, in the vertical direction of the photomask. Vertical positioning pins are provided to determine the position. Of course, such an exposure apparatus of the present invention can also be applied to exposure in a plate making process when photoetching a lead frame.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described. FIG. 1A is a schematic view of an example of an embodiment of an exposure apparatus of the present invention, and FIG.
FIG. 2 is a diagram showing a state in which the supporting frame portion on the first side is vacuum-adhered to the processing base material coated with the photosensitive material 170, and FIG.
FIG. 3 is a schematic view seen from the direction A2 in FIG.
FIG. 4A is a view of the support frame portion shown in FIG.
FIG. 4B is a diagram of an arrangement example of suction holes (also referred to as vacuum suction holes) of the suction unit 112, and FIG. 5 is a diagram for explaining a relative position change between the photomask and the support frame.
FIG. 5A is a partial cross-sectional view including the adsorption portion of the present application, and FIG.
FIG. 6 is a partial cross-sectional view of a conventional photomask fixing portion. still,
FIG. 1A is a view seen from A3-A4 in FIG. Figure 5
In (a), the suction hole 152 and the vacuum suction hole 155.
Are omitted. 1 to 5, 110 and 115
Is a support frame, 110A is an inner position of the support frame, 111, 11
6 are vertical positioning pins, 112 and 117 are lateral positioning pins, 120 and 125 are light source parts, 121 and 126 are light sources, 122 and 127 are mirrors, 130 and 135 are support frame holding control parts, and 140 and 145 are A packing, 150 is a suction part (also a packing), 151 is a suction surface, 152 is a suction hole (also referred to as a vacuum suction hole), 155 is a vacuum suction hole, and 160 and 165 are photomasks (also referred to as pattern plates). , 170 is a processing substrate, 175 is a photosensitive material, 1
80 is a rail, 185 is a rail receiving portion, 190 is a vacuum region, 210 is a support frame, 210a and 210b are groove portions, 25
0 and 257 are packings, 255 is a vacuum drawing hole, 260 is a photomask, and 280 is a space.

An embodiment of the exposure apparatus of the present invention will be described with reference to FIG. In the exposure apparatus of this example, the large-sized photomasks 160 and 165 are mounted on the support frames 110 and 115 while standing in a substantially vertical direction, respectively. Used in the plate-making process of photo-etching processing for exposing and exposing the patterns of the photomasks 160 and 165 as latent images on the photosensitive material 175 disposed on the surface of the processing substrate, respectively. In the exposure apparatus for double-sided exposure, the support frame 110, the support frame holding control unit 130, and the light source unit 120 are provided on one surface side of the processing base material 170 coated with the photosensitive material 175 material. The support frame 115, the support frame holding control unit 135, and the light source unit 125 are provided on the other surface side of the processing base material 170. At the time of exposure, the support frames 110 and 115 are controlled by the support frame holding control unit, respectively, and are vacuum-adhered to the photosensitive material 170 on each surface of the processing substrate 170 coated with the photosensitive material 175 material. The exposure is performed in the exposed state.

In the support frame 110, two vertical positioning pins are provided at two lower sides thereof so as to be substantially horizontal to each other and to determine the vertical position of the photomask in the vertical direction. 111 is provided, and while holding the vertical position of the photomask in the vertical direction at a predetermined position, one side surface portion of the photomask in the lateral direction is brought into contact with the photomask, and the photomask is aligned along the support frame. It has a lateral locating pin 112 for determining the lateral position. When mounting the photomask 160, the support frame 110 first presses the photomask against each positioning pin,
The suction part 150 sucks the periphery of the photomask. Similarly, the support frame 115 has two lower positions,
One vertical positioning pin 116 is provided to determine the vertical position of the photomask in the vertical direction so that they are substantially horizontal to each other. While holding the directional position at a predetermined position, one lateral side portion of the photomask is applied to the lateral side portion, and a lateral locating pin 117 for determining the lateral position of the photomask along the support frame is provided. It is a thing. The support frame 115 has basically the same structure as the support frame 110, and in the same manner as the support frame 110, the suction part sucks the periphery of the photomask.

The supporting portions 110 and 115 are suction portions for sucking by vacuuming the entire periphery of the surfaces of the photomasks 160 and 165 opposite to the pattern forming layer side (FIG. 1B).
No. 150) is provided along the entire frame shape along the entire frame shape. The suction portion 150 is provided with a large number of small holes (corresponding to the suction holes 152 in FIG. 4), and the support frame 11
The holes 0 and 115 for vacuuming the suction unit 150 (see FIG.
Vacuum drawing hole (15 in FIG. 1B) subsequent to 152 in FIG.
(Corresponding to No. 5), a vacuuming pipe or groove (not shown) is provided over the entire circumference. And
A large number of small holes (corresponding to the suction holes 152 in FIG. 4) of the suction portion 150 reaching the suction surface 151 vacuum the entire periphery of the photomask. A large number of small holes (corresponding to the suction holes 152 in FIG. 4) of the suction portion 150 are usually shown in FIG.
Although the hole shape is as shown in FIGS. 4A and 4B, the shape is not limited to this.

As shown in FIG. 1B, the suction portion 150
Is made of a flat plate-like packing, and the suction surface 151 for sucking the photomask is flat, so that when the photomask is sucked, the deformation of the suction portion at each position can be made uniform. As a result, when adsorbing the photomask,
The deformation of the suction portion at each position can be made uniform, and the relative positional change between the support frame and the photomask due to the non-uniform deformation of the suction portion at each position can be suppressed to an extremely small level. The suction surface 151 preferably has a large friction coefficient from the viewpoint of preventing slippage, and a rubber material is generally used, but the suction surface 151 is not limited to this. Packing 14 for this vacuum
Numerals 0 and 145 are packings for preventing vacuum leakage when performing main vacuuming when the photomasks 160 and 165 on both surfaces of the processing base material 170 are adhered to each other after adsorbing the photomask.

The support frame portions 110, 115 are
The supporting photomask is brought into close contact with the photosensitive material 175 of the processing base 170. Incidentally, a stainless material, a resin material or the like is usually used as a base material of the support frame portion. The support frame holding control units 130 and 135 respectively support the support frame unit 11.
0 and 115 are held, and vacuum suction to the support frame portion of the photomask, vacuuming between the support frame portions 110 and 115, or vacuuming or releasing the vacuum between the support frame portions 110 and 115 and the processing substrate 170 are performed. To control. The support frame portion 110 (11
5) The area of the support frame holding control unit 130 (135) corresponding to the window (the inside area of 120A in FIG. 1B) for transmitting the exposure light from the inner light source 120 (125) is the window portion or the exposure light transmissivity. Composed of material. As shown in FIG. 2, the support frame portions 110 and 115 respectively include the support frame holding control portion 13
Via the rail receiving portion 185 of 0, 135, the rail 18
It is possible to change the distance from the processing substrate 170 coated with the photosensitive material 175 by this movement. As the light sources 121 and 126,
A Xe lamp, a metal halide lamp, a mercury lamp, etc. are used.

The processing base material 170 is a continuous metal sheet in the shape of a strip, and a photosensitive material 175 is coated on the front and back surfaces of the metal base sheet, and the exposure is performed in a stretched state. When the product is a shadow mask, low carbon steel or iron-nickel alloy (for example, amber material, 36% nickel-iron alloy) is used, and when the product is a lead frame, copper material or iron-nickel alloy (for example 42 Alloy, 42% nickel-iron alloy)
Etc. are used. And as the photosensitive material 175,
Usually, various types such as casein type and PVA type are used.

As the photomasks 160 and 165, a silver salt dry plate having a width of 24 inches and a height of 32 inches or a size larger than this, on which a pattern is formed, is usually used. A frame and a light source are prepared.

The support frame portion 110 is vacuum-tightly attached, and is shown in FIG.
As shown in (b), the photomask 160 is brought into close contact with the photosensitive material 175. At this time, a vacuum is generated between the support frame portion 110, the photomask 160, and the processing base material 170 coated with the photosensitive material 175. Region 190 is formed.

Next, an example of the exposure operation of the apparatus of this example will be briefly described. First, in a state where the support frame portions 110 and 115 are separated from the processing base material 170, the photomasks 160 and 165 are set to predetermined positions by aligning with the respective positioning pins, and then the suction portions are attached to these. The photomasks 160 and 165 are vacuum-adsorbed and fixed at their peripheral portions. This state corresponds to the state shown in FIGS. Then, in a state in which the processing base material 170 is stretched and stopped, the rail receiving portion 1 of the support frame holding control portions 130 and 135.
By 85, the supporting frame portions 110 and 115 are respectively attached to the processing base material 170 side on the rail, and the supporting frame holding control portion 13 is provided.
0,135 and the photomask 160,
In a state in which the photomasks 165 are in contact with the photosensitive material 175, respectively, a vacuum is drawn between the support frame part 110, the photomask 160 and the support frame part 115, and the photomask 165, and the photomasks 160 and 165 are used as a processing base material. It adheres to the photosensitive material 175 of 170. In the state where the photomask and the photosensitive material 175 are in close contact with each other, the light sources 120 and 125 irradiate the backside of the photomask with exposure light to expose the photosensitive material 170 on both sides of the processing base material 170. , Forming latent images corresponding to the photomasks, respectively. After that, the support frame 110, the photomask 160, and the support frame 1
15. The vacuum is released between the photomask 165 and the photomask 165, and the photosensitive material 1 of the photomasks 160 and 165 and the processing base material 170 is released.
Release the vacuum contact with 75. Next, each support frame portion is moved to a predetermined position on the rail 180 so as to be separated from the processing base material 170, and the processing base material is conveyed. Similarly, the photomask and the processing base material 170 are moved. Photosensitive material 1
The operation of close contact with 75 and exposure is repeated.

After the exposure, if necessary, each supporting frame portion is moved to a predetermined position on the rail 180 to a photomask exchange position so as to be separated from the processing base material 170, and the photomask vacuum of the supporting frame portion is moved. Release the vacuum for suction and remove the photomask from the support frame. Then, another photomask is newly attached to the support frame portion in the same manner, and the same exposure is performed. Thus, the exposure apparatus of this example can operate, but this is an example, and the present invention is not limited to this.

Now, the relative position change between the suction portion 150 and the support frame will be further described with reference to FIG. First, an example of a conventional photomask contact method will be briefly described. The photomask adhesion method mentioned here is such that the photomask is pressed against each alignment pin of the support frame, and a pair of packings are provided along the entire circumference of the frame (Fig. 5).
This is performed by vacuuming the space portion (corresponding to 250 and 257 in FIG. 5B), the photomask, and the support frame (corresponding to the space portion 280 in FIG. 5B). Here, a pair of packings (corresponding to 250 and 257 in FIG. 5B) are
Like the suction unit 150 of the present example, they are provided along the entire circumference of the frame of the support frame, and the evacuation of the space is performed by a pair of packings (250, 25 in FIG. 5B).
7)). As the packings 250 and 257, tube-shaped packings embedded in the grooves 210a and 210b provided in the support frame 210 are used, and when the photomask 260 is not adsorbed, the cross section thereof is set. In the photomask surface direction (left and right direction in FIG. 5B), the shape is left-right symmetrical and substantially circular. However, in this case, the cross-sectional shape of the deformed packing is not uniformly deformed when the photomask is closely attached. Depending on the location, as shown in FIG. 5B, the deformed cross-sectional shape, such as the inner side portions of the packings 250 and 257 that are deformed toward the inner side of the frame, may have a modified cross-sectional shape (see FIG. 5B. ), Left and right direction) is not symmetrical. That is, in the case of this conventional photomask contact method, the deformation of the packings 250 and 257 may become uneven depending on the location, and the relative position of the photomask and the support frame changes due to the restoring force of the packing. I have something to do.
On the other hand, in the case of this example, the contact portion 150 is entirely formed of a flat plate-shaped packing, and the packing itself does not deform unevenly as in the conventional method. Further, since the suction hole 152 and the vacuum suction hole 155 are provided in the suction portion 150 region, the vacuum suction packing may have a simple structure, and may have a circular cross section as in this example. After all, in the case of the present example, the deformation of the packing can be made almost uniform regardless of the position when the photomask is adhered, and the photoinduced deformation of the packing when the photomask is adhered, as in the conventional method described above. It is possible to solve the problem of the change in the relative position of the mask and the support frame. Incidentally, FIG. 5 (b)
The packing 257 of FIG.
(Corresponding to 140 in (a)).

[0022]

As described above, according to the present invention, in the state where a large-sized photomask is set up in a substantially vertical direction and mounted on a support frame, the backside of the photomask on which the pattern is not formed is exposed, An exposure device for photolithography for exposing and forming a pattern of a photomask on a photosensitive material provided on a surface portion of a processing base material as a latent image, the relative position of the support frame and the photomask. It has become possible to provide an exposure apparatus that can determine the position accuracy with high accuracy. In particular, this makes it possible to accurately deal with the recent increase in definition and size of shadow masks in the shadow mask plate making process.

[Brief description of drawings]

1A is a schematic view of an example of an embodiment of an exposure apparatus of the present invention, and FIG. 1B is an A1 of a processing base material 170.
It is the figure which showed the state which carried out the vacuum adhesion of the support frame part of the side to the processing base material which coated the photosensitive material 170.

FIG. 2 is a schematic view seen from the direction A2 in FIG.

FIG. 3 is a view of the support frame portion shown in FIG. 1A as seen from the direction A1.

4 (a) and 4 (b) are diagrams of arrangement examples of suction holes (also referred to as vacuum suction holes) of a suction unit 112. FIG.

5A and 5B are views for explaining a relative position change between the photomask and the support frame, FIG. 5A is a partial cross-sectional view including a suction portion of the present application, and FIG. It is a partial cross section figure of the conventional photomask fixing | fixed part.

[Explanation of symbols]

110, 115 Support frame 110A Inner position of support frame 111, 116 Vertical positioning pin 112, 117 Horizontal positioning pin 120, 125 Light source section 121, 126 Light source 122, 127 Mirror 130, 135 Support frame holding control section 140, 145 Packing 150 Adsorption part (also packing) 151 Adsorption surface 152 Adsorption hole (also referred to as vacuum evacuation hole) 155 Vacuum evacuation holes 160 and 165 Photomask (also referred to as pattern plate) 170 Processing substrate 175 Photosensitive material 180 Rail 185 Rail receiving portion 190 Vacuum region 210 Support frames 210a, 210b Groove portions 250, 257 Packing 255 Vacuum drawing hole 260 Photomask 280 Space portion

Claims (4)

[Claims] 1. A large-sized photomask is set up in a substantially vertical direction and mounted on a support frame, and is exposed from the back surface side on which the pattern of the photomask is not formed to expose the pattern of the photomask to a processing base. An exposure apparatus for photolithography for exposing and forming a latent image on a photosensitive material disposed on a surface portion of a material, wherein a support frame has an adsorption portion for fixing a photomask, and a frame shape thereof. Along the entire circumference of the frame, the photomask is adsorbed and fixed on the entire periphery by the adsorbing part.
The adsorption surface for adsorbing the photomask is made of a flat plate-like packing, and the adsorption portion is provided with adsorption holes for evacuation that reach the adsorption surface over the entire circumference of the support frame. The exposure apparatus is characterized in that 2. The suction hole for vacuum suction provided on the suction surface according to claim 1, wherein a large number of small holes are arranged all around the support frame. Exposure equipment. 3. The exposure apparatus according to claim 1, wherein the suction surface of the suction portion for sucking the photomask is made of a rubber material having a high coefficient of static friction. 4. The photosensitive material provided on the front and back surfaces of the substrate for processing according to claim 1, and a photomask held by a supporting frame for each of the photosensitive materials, from the back surface side of the photomask, respectively. Double-sided exposure used in a plate-making process for producing a shadow mask, in which a photomask and a photosensitive material provided on the surface of a processing substrate are vacuum-contacted and exposed at about the same time to form a latent image. An exposure apparatus characterized by being an apparatus.