JP2008024956A - Alignment device and alignment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alignment device and an alignment method capable of positioning a mask with high accuracy, and enhancing the workability. <P>SOLUTION: The alignment device 1 comprises a substrate holder 2 for supporting a substrate 3, a mask 4 which is positioned with respect to the substrate 3, and has an opening for demarcating a treatment area on the substrate 3, and a shape control means (an electrode 6, a wiring 7, a conduction control plate 8) for partially changing the shape of the mask 4 by heating at least a part of the mask 4. In an alignment process of the mask 4 with respect to the substrate 3, each part (an alignment mark 4M) of the mask is aligned to a plurality of alignment positions (alignment marks 3M) on the substrate 3. When a part of the mask 4 is not matched to the alignment position, the mask 4 is matched to the alignment position by partially changing the shape by heating at least a part of the mask 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an alignment apparatus and an alignment method for accurately aligning a substrate and a mask.

  2. Description of the Related Art An alignment technique for aligning a substrate and a mask with high accuracy is important in a film forming apparatus for forming a film by overlapping a mask on a substrate. For example, in the manufacture of an organic EL (Electro Luminescence) display device using an organic thin film, a predetermined mask pattern (opening) is formed when three types of organic thin films that generate light of three primary colors are formed on the same substrate. A predetermined film forming process such as vapor deposition or sputtering is performed by positioning the mask on which the film is formed with high accuracy on the film forming surface of the substrate.

  By the way, conventionally, in a film forming apparatus used for manufacturing an organic EL display device, a metal mask made of a magnetic material is used as a mask. After the substrate is aligned on the mask, a magnet is formed on the substrate. Are stacked, and the substrate is sandwiched between the magnet and the mask to maintain the contact state between the substrate and the mask aligned with each other (see Patent Document 1 below).

  Further, in Patent Document 2 below, a thin plate-like vacuum deposition mask formed of a magnetic material has a structure having a holding region for a mask holder, a film formation region having an opening, and a region for reducing distortion of the mask. Thus, it has been disclosed that the influence of the distortion and deflection of the mask is suppressed and the adhesion between the vapor deposition mask and the substrate is improved.

JP 2001-358202 A JP 2005-310472 A

  Conventionally, the mask is placed on the substrate by moving the mask to the marker position (alignment position) on the substrate while monitoring with a CCD (Charge Coupled Device) camera or the like. Usually, there are at least two alignment positions, and the alignment between the substrate and the mask is completed by moving the mask so as to match each alignment position.

However, with the recent increase in area of the substrate, it is difficult to perform alignment between the substrate and the mask with high accuracy.
That is, as the substrate becomes larger, the mask becomes larger and deformation tends to occur. In particular, when a fine distortion, deflection, waviness, or the like is generated at the outer edge of the mask, the mask may not be aligned with the alignment position, and high-accuracy alignment may not be performed. Further, if the mask alignment process is not completed, it is not possible to proceed to the next process (film formation process or the like), resulting in an increase in alignment work time and a loss of productivity.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an alignment apparatus and an alignment method capable of aligning a mask with high accuracy and improving workability.

  In solving the above problems, an alignment apparatus of the present invention includes a substrate support means for supporting a substrate to be processed, and a mask that is positioned with respect to the substrate to be processed and has an opening that divides a processing region on the substrate to be processed. And shape control means for partially changing the shape of the mask by heating at least a part of the mask.

  The alignment method of the present invention includes a step of opposingly arranging the mask on a substrate to be processed, and a step of aligning each part of the mask at a plurality of alignment positions provided on the substrate to be processed. When a part of the mask does not conform to the alignment position, the mask is adapted to the alignment position by heating at least a part of the mask and partially changing the shape.

  As described above, according to the present invention, when a part of the mask does not match the alignment position, the mask is positively aligned using the thermal expansion of the mask by heating at least a part of the mask. ing. As a result, the deformation of the mask 4 is corrected, high-accuracy alignment between the mask and the substrate is possible, and the alignment work time can be shortened and the productivity can be improved.

  As the mask heating mechanism, energization heating or lamp heating for the mask can be used. The energization heating includes energization heating to the heater built in the mask in addition to energization heating to the mask constituent material. Although the heating position of a mask is not specifically limited, For example, the local heating with respect to the mask area | region which does not match an alignment position is mentioned.

  As described above, according to the present invention, high-precision alignment between the mask and the substrate is possible, and it is possible to shorten the alignment work time and improve the productivity.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an alignment apparatus 1 according to an embodiment of the present invention. In the present embodiment, the alignment apparatus 1 is installed inside a film forming apparatus (not shown) (evaporation apparatus, sputtering apparatus, etc.).

  A substrate 3 as a substrate to be processed is disposed on a substrate holder 2 as a substrate support means. On the substrate 3, the mask 4 is disposed so as to be opposed to each other in an aligned state. The substrate holder 2 is for supporting the substrate 3, and the configuration is not particularly limited. For example, the substrate holder 2 has a magnet structure such as a permanent magnet material or an electromagnet. On the other hand, the mask 4 is made of a magnetic material, and is magnetized (magnetized) by the substrate holder 2 to sandwich the substrate 3 with the substrate holder 2.

  As the substrate 3, a rectangular large glass substrate or the like is used. Alignment marks 3M for alignment with the mask 4 are provided at the four corner positions of the substrate 3, respectively. Each alignment mark 3M is aligned with each of the four detection holes 2a formed in the substrate holder 2, and each alignment mark 3M is respectively detected by the four CCD cameras 5 arranged below the substrate holder 2 in FIG. Monitored.

  The mask 4 has an opening formation region 4A in which openings for partitioning the processing region on the substrate 3 are formed, and a frame body 4B that supports the opening formation region 4A. The opening forming region 4A is formed of a rectangular thin plate having a shape and size substantially the same as the substrate 3. In the opening formation region 4A, an opening having a predetermined shape is formed that partitions the processing region on the substrate 3, and the substrate is exposed to the surface of the substrate exposed through the opening by being disposed in close contact with the surface to be processed of the substrate 3. Predetermined processing such as film formation and etching is performed on the processing region.

  Alignment marks 4M for alignment with the substrate 3 are provided at the four corner positions of the opening formation region 4A of the mask 4, respectively. Each alignment mark 4M is provided at a position that matches the corresponding alignment mark 3M on the substrate 3 when the mask 4 is properly aligned with the substrate 3. The formation positions and the number of the alignment marks 3M and 4M are not limited to the above example, and may be formed in at least two places.

  In the alignment process of the mask 4 with respect to the substrate 3, the mark positions of the alignment mark 3M and the alignment mark 4M are made to coincide with each other using the CCD camera 5. When the alignment mark 3M matches the alignment mark 4M of the mask 4 at the four corner positions of the substrate 3, the alignment operation of the mask 4 with respect to the substrate 3 is completed.

  Here, with the recent increase in size of the substrate 3, the mask 4 is also increased in size, so that the mask 4 is easily deformed. At this time, if a deformation such as fine distortion, bending, or undulation of the opening forming region 4A or the frame body 4B of the mask 4 occurs, the alignment mark 4M of the mask 4 does not match the alignment mark 3M of the substrate 3, and the substrate 3 and the mask 4 may not be aligned with high accuracy. Further, if the alignment process of the mask 4 is not completed, it is not possible to move to the next process (film formation process or the like), so that the alignment work time increases and the productivity is impaired.

  Therefore, the alignment apparatus 1 of the present embodiment includes a shape control unit that partially changes the shape of the mask 4 by heating at least a part of the mask 4, and a part of the mask 4 is adapted to the alignment position. When not, the predetermined part of the mask is heated to partially change the shape, thereby correcting the deflection of the mask 4 and adapting the mask 4 to the alignment position.

  In the present embodiment, the shape control means includes a plurality of electrodes 6 formed along the frame body 4B of the mask 4, and an energization control plate 8 connected to the plurality of electrodes 6 via wiring portions 7, respectively. It is comprised with the electricity supply mechanism provided with. The energization control plate 8 selects a current source that generates a supply current between any electrodes 6, an element that adjusts the amount of current, and an electrode 6 that should be energized based on an output from the CCD camera 5, and the amount of supply current The control unit to decide is installed.

  In FIG. 1, the energization control plate 8 is shown only on one side of the mask 4, but even if all the electrodes 6 on the mask 4 are connected to the illustrated energization control plate 8. Alternatively, the energization control plate 8 may be arranged corresponding to each side of the mask 4. Or you may comprise the electricity supply control board 8 cyclically | annularly so that the circumference | surroundings of the mask 4 may be enclosed.

  The energization control plate 8 supplies a predetermined amount of current between predetermined electrodes 6 arranged along the periphery of the mask formation region 4 </ b> A based on the output of the CCD camera 5, thereby defining a predetermined portion of the mask 4. The energization heating is performed, and the alignment mark 4M of the mask 4 is adapted to the alignment mark 3M of the substrate 3 using the deformation caused by the thermal expansion. The shape change portion, shape change direction, shape change amount, and the like of the mask 4 are controlled by the combination of the selected electrodes 6, the current application method, the current magnitude, and the like.

  2 to 4 are schematic views showing an example of a conduction mode for the mask 4. FIG. 2 shows how the shape of the corners of the mask 4 is changed by energizing between the pair of electrodes 6 sandwiching the four corners of the mask 4. FIG. 3 shows a state in which current is supplied along each side of the mask 4 to deform the frame 4 in the side direction. FIG. 4 shows how the shape of the entire mask 4 is changed. The set of electrodes 6 to be energized is not limited to one set, and a plurality of sets may be performed simultaneously.

  In the alignment apparatus 1 of the present embodiment configured as described above, first, the substrate 3 is placed on the substrate holder 2. At this time, the substrate 3 is placed on the substrate holder 2 so that the alignment mark 3M of the substrate 3 is aligned with the detection hole 2a of the substrate holder 2.

  Next, the mask 4 is disposed to face the substrate 3. The alignment of the mask 4 with respect to the substrate 3 is performed by aligning each part of the mask 4 at a plurality of alignment positions provided on the substrate 3. In the present embodiment, the alignment work of the alignment marks 3M and 4M of the substrate 3 and the mask 4 is performed by the CCD camera 5 through the detection hole 2a. The mask 4 is moved by a mask holder (not shown) that supports the mask 4.

  When the alignment marks 4 are all matched at the four corner positions of the substrate 3, the mask 4 is placed on the substrate 3 at that position, and the mask 4 is attracted to the substrate holder 2 by the magnet action of the substrate holder 2. Thereby, the substrate 3 is positioned and clamped between the substrate holder 2 and the mask 4. Thus, the alignment process is completed, and the process proceeds to the film forming process.

  On the other hand, if the mask 4 is bent, all of the alignment marks 3M and 4M of the substrate 3 and the mask 4 may not be matched at the same time. In this case, based on the output of the CCD camera 5 that monitors the suitability of the alignment position, a mask part that does not match the alignment is detected. Then, a combination of electrodes 6 that can correct the mask shape by energization heating to the mask portion, a necessary current amount, and the like are determined, and partial energization heating of the mask 4 is performed via the energization control plate 8. Thereby, the shape of the energized part of the mask 4 changes due to thermal expansion, and the deflection of the mask 4 is corrected.

  As described above, the alignment marks 3M and 4M of the substrate 3 and the mask 4 can be simultaneously matched by the energization heating action on at least a part of the mask 4. Thereby, it is possible to prevent the alignment workability from being deteriorated due to the bending of the mask 4 and the like, to realize highly accurate alignment between the substrate 3 and the mask 4, and to shorten the alignment process time. Further, it is possible to improve productivity by promptly shifting to the film forming process.

  The energization control of the mask 4 is not limited to being part of the mask 4 but also includes the case of the entire mask 4. Moreover, when the mask 4 is comprised by the aggregate | assembly of a some mask division piece, as shown in FIG. 5, it can comprise so that the above-mentioned electric heating can be performed about each mask division piece 4d. Note that the present invention is not limited to the case where the energization heating mechanism is applied to all of the mask divided pieces 4d, and the energization heating mechanism may be provided only for at least one mask divided piece.

  As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to this, A various deformation | transformation is possible based on the technical idea of this invention.

  For example, in the above embodiment, as the means for energizing and heating the mask 4, resistance heating of the mask 4 itself when a plurality of electrodes 6 are formed on the frame 4 </ b> B of the mask 4 and current is supplied between the arbitrary plurality of electrodes 6. Instead of this, as shown in FIGS. 6A and 6B, the mask 4 is heated by energizing the heating wire (resistance heating wire) 10 attached to an arbitrary position of the frame 4B of the mask 4 as shown in FIGS. May be performed. 6A shows an example in which the heating wire 10 is intermittently attached along the side direction of the frame 10 of the mask 4, and FIG. 6B shows the heating wire along the side direction of the frame 10 of the mask 4. The example which attached 10 continuously is shown.

  Further, as shown in FIG. 7, a heater 11 is embedded in a predetermined portion of the frame 4 </ b> B of the mask 4, and an arbitrary heater 11 corresponding to the portion of the mask 4 to be subjected to shape change control is selectively energized and heated. You may comprise the electricity heating mechanism of this invention.

  Alternatively, as shown in FIG. 8, an irradiation region 12 of a heating lamp (infrared lamp) is set at a predetermined portion of the frame 4B of the mask 4, and an arbitrary irradiation region 12 corresponding to the portion of the mask 4 whose shape change is to be controlled. May be selectively irradiated with a lamp to constitute the shape control means of the present invention.

  Furthermore, for example, it is possible to apply an alternating magnetic field to a predetermined part of the mask 4 to induce generation of eddy currents in the mask 4 and to configure a heating mechanism of the mask 4 by the resistance heating action of the eddy currents. . In addition to this, a known heating mechanism can be applied to the heating operation for the mask 4.

It is a schematic block diagram of the alignment apparatus by embodiment of this invention. It is a schematic diagram explaining an example of the electricity supply form of the mask in the alignment apparatus shown in FIG. It is a schematic diagram explaining an example of the electricity supply form of the mask in the alignment apparatus shown in FIG. It is a schematic diagram explaining an example of the electricity supply form of the mask in the alignment apparatus shown in FIG. It is a schematic diagram explaining the modification of the structure of a mask and the electricity supply form in the alignment apparatus shown in FIG. It is a mask top view which shows the modification of the structure of the energization heating mechanism of the mask in the alignment apparatus shown in FIG. It is a mask top view which shows the modification of the structure of the heating mechanism of the mask in the alignment apparatus shown in FIG. It is a mask top view which shows the modification of the structure of the heating mechanism of the mask in the alignment apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Alignment apparatus 2 Substrate holder 2a Detection hole 3 Substrate 3M Alignment mark 4 Mask 4A Opening formation area 4B Frame 4M Alignment mark 5 CCD camera 6 Electrode 7 Wiring 8 Current supply control part 10 Heating wire 11 Heater 12 Lamp irradiation area

Claims (6)

Substrate support means for supporting the substrate to be processed;
A mask that is positioned with respect to the substrate to be processed and has an opening that defines a processing region on the substrate to be processed;
An alignment apparatus comprising: shape control means for partially changing the shape of the mask by heating at least a part of the mask. The alignment apparatus according to claim 1, wherein the shape control unit includes an energization mechanism that energizes and heats at least a part of the mask. The alignment apparatus according to claim 1, wherein a plurality of electrodes for energization heating are arranged along the periphery of the mask. The alignment apparatus according to claim 1, wherein the mask is formed of an assembly of a plurality of mask division pieces, and at least one of the mask division pieces is provided with a terminal portion for energization heating. An alignment method for aligning a mask having an opening that defines a processing region on the target substrate with respect to the target substrate,
Placing the mask oppositely on the substrate to be processed;
And a step of aligning each part of the mask to an alignment position provided on the substrate to be processed.
When a part of the mask does not conform to the alignment position, the mask is adapted to the alignment position by heating at least a part of the mask and partially changing the shape. The alignment method according to claim 5, wherein the mask is heated by energization heating of the mask.

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