JPH03290917A - Mask holder - Google Patents

Abstract

PURPOSE:To control optimum pressing force, improve positioning accuracy and make positioning smooth by limiting an opening angle of fingers so that a claw is engaged in a groove on a mask side while the fingers are open. CONSTITUTION:When a mask 4 is positioned and mounted on a mask stage 8, the mask 4 is press-fitted to a V-block 9 with fingers 11 open. Since the mask 4 can freely move in parallel to a mask surface by a function of a parallel spring 19 at this time, movement along a V-groove is free and a pressing motion for smooth positioning is possible. A shaft 20a of a sucking member 20 is returned toward a main body 17 according to pressing force of the mash 4 against the V-block 7 so as to press a plate spring 22 to have it deformed, and a resistance value of a strain gage changes to allow the pressing force to be detected. Control of the pressing force wherein positioning pressure is feedback controlled or pressing force is weakened at the time of theta driving or sucking the mask is possible based on the detected pressing force.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor exposure apparatus, and particularly to a mask holding device (mask hunt) in an X-ray mask transport mechanism.

[Prior Art] Recent exposure apparatuses for manufacturing semiconductor devices such as ICs and LSIs are capable of printing with higher resolution, for example, wavelengths of 1 to 150, as semiconductor devices become more highly integrated. X of
Exposure devices using lines have been proposed. Due to the characteristics of the exposure light, such an X-ray exposure apparatus has a structure that is significantly different from a mask whose substrate is made of a material such as glass used in a conventional exposure apparatus that uses ultraviolet light as the exposure light. Specifically, a mask is used in which a pattern is formed on a thin film using an X-ray absorber, and the film is supported by a substrate or the like.

Generally, the thickness of the support film is 5 to 10 μm in the case of an organic material film (eg, polyimide, etc.), and about 2 to 5 μm in the case of an inorganic material film (eg, SiN, SiC, etc.).

The holding frame varies depending on the manufacturing process of the mask blank, but
When the support film is an inorganic material, an St plate having a thickness of 0.5 to 3IIIn is used. Further, when the support film is an organic material,
For example, glass, ceramics, etc. of about 5 mm are used. In either case, in order to apply tension evenly to the support film on which the X-ray absorber is formed and to minimize local distortion, the shape is basically annular and has rotational symmetry. There is.

Furthermore, if the holding frame is very thin (3 mm or less) due to manufacturing reasons (for example, to simplify etching), a reinforcing body may be attached to the holding frame for rigidity, strength, and reinforcement. is well known, and low expansion glass, quartz glass, etc. are used.

[Problems to be Solved by the Invention] However, when the mask used in such an X-ray exposure device is automatically conveyed within the device, due to its special configuration,
There were the following problems.

Conventionally, in the mechanism for conveying the mask, the mask is generally held mechanically, but as the mask has an annular shape as described above, when trying to hold the sides, the area that can be gripped is very small. Moreover, even if measures are taken to increase the area, as mentioned above, the support film is only a few micrometers thick or less, and is extremely brittle, and will deform or break if a large force is applied in a certain direction and local strain is applied. may lead to.

Furthermore, the X-ray exposure atmosphere is in a vacuum or low-pressure He, making it impossible to use the conventional vacuum suction method.

Therefore, sufficient gripping force to hold the mask against the external force applied to the mask during transportation could not be obtained, and highly accurate automatic transportation could not be performed.

Further, because of the annular shape, it was difficult to determine the direction of rotation, and it took time to position the mask after transporting the mask, leading to a reduction in throughput.

When positioning an X-ray mask, positioning on the XY plane is performed by bringing the mask into contact with the positioning V block, and positioning for 2 rotations (rotation in the θ direction) is performed by rotating the θ stage of the mask stage. This is done by

The mask hand in the conventional mask transport mechanism does not have a means for detecting the external force applied to the mask, so it presses the mask against the positioning V block with a certain amount of strong force to position it in the XY force direction, and in this state it performs θ drive. It was also performing a mask suction operation. Therefore, it is not possible to properly control the pressing force, and there are problems such as generation of dust and variation in pattern distortion due to sliding friction between the mask and the V block, and a decrease in positioning accuracy due to wear and tear of the V block.

Further, the conventional mask hand does not have a sufficient degree of freedom of movement during positioning, and cannot perform smooth positioning operations.

In addition, during positioning or transportation, the hunt may open and the mask may fall.

The present invention has been made in view of the above-mentioned shortcomings of the prior art, and enables appropriate pressing force control, improves positioning accuracy, smoothes the movement of positioning operations, and securely holds the mask to prevent it from falling. The purpose is to provide a mask holding device that eliminates danger.

[Means for Solving the Problems] In order to achieve the above object, a mask holding device according to the present invention includes a main body, two fingers provided on both sides of the main body that can be opened and closed, and tips of the fingers. A claw for engaging with a groove on the side surface of the mask to be held, a means for detecting an external force applied to the mask from the mask tip side to the main body side while the mask is being held, and a hook parallel to the mask surface. and elastic support means for movably holding the mask relative to the main body, and the finger portions are arranged such that the claws are engaged in grooves on the sides of the mask when the two finger portions are open. The opening angle is limited.

[Operation] The force applied to the V block during mask positioning is detected by the detection means. When pressed against the V block, the mask can move freely in a plane perpendicular to the mask transport direction and parallel to the mask surface, and (1) slide smoothly along the block surface. Furthermore, even if the fingers of the second tree open, the claws remain engaged with the mask and the mask does not come off.

[Example 5] The configuration of an example of a mask conveying device to which the present invention is applied is shown in the fifth example.
As shown in the figure. The mask transport device 1 includes a guide section 2 and a mask hand 3. 4 is an X-ray mask, 5 is a connecting portion, 6 is a linear guide, and 7 is a drive belt. Mask hand 3 is
As will be described later, the mask 4 is held and slid along the linear guide 6 in the direction of arrow A. 8 is the mask stage, 9
1 is a V block, and 10 is a mask suction section. The mask 4 held by the mask hand 3 is pressed against the V-block 9 of the mask stage 8 for positioning, and after being roughly positioned in the θ direction, the mask 4 is fixedly held on the mask stage 8 by suction.

FIG. 1 shows details of a mask hand according to an embodiment of the present invention. 11 is a finger, 12 is a nail made of wire, 13 is a finger 11
The fulcrum 14 is a groove formed on the side surface of the mask 4. The grooves 14 may be formed in an annular shape all around the circumferential side surface of the mask 4, or may be formed as parallel straight grooves at two or more opposing locations as shown in the figure. 15 is a solenoid, 16 is a compression spring, 17 is a hand body, 18 is a center suction part, 19 is a parallel plate spring, 20 is a suction member, 2
Reference numeral 1 designates an intermediate member, 22 a force-detecting plate spring for pressing, 23 a strain gauge, and 24 a magnetic material embedded in the side surface of the mask 4. The fingers 11 are attached to both sides of the main body 17 so that they can be opened and closed about a fulcrum 13. The opening/closing operation is performed by a solenoid 15. The compression spring 16 always urges the finger 11 in the closing direction.

The claw 12 provided at the tip of the finger 11 is as shown in FIG.
The mask 4 is held by engaging in the grooves 14 on both sides of the mask 4. FIG. 3 shows the opened and closed states of the finger 11. The figure (b) shows the closed state, and the figure (a) shows the open state. (a) As shown in the figure, when the fingers 11 are opened, the distance between the claws 12 on both sides is smaller than the diameter of the mask 4, so the claws 12 do not come off the grooves 14 of the mask 4. In this case, the mask 4 is attached and detached from the tip side of the hand.

The intermediate member 21 is connected to the main body 17 via the parallel leaf spring 19.
is installed. The adsorption member 20 is slidably attached to this intermediate member via a shaft 20a. A center suction portion 18 made of a solenoid is fixed to the suction member 20 . The center attraction portion 18 attracts the magnetic body 24 on the mask 4 side, and the attraction member 20 and the mask 4 are integrated.

A leaf spring 22 is fixed to the intermediate member 21, and this leaf spring 2
A strain gauge 23 is attached to 2. The plate spring 22 comes into contact with the tip of the shaft 20a of the suction member 20.

In such a configuration, the mask 4 is placed on the mask stage 8.
(FIG. 5) When positioning and mounting the mask 4 on the top, press the mask 4 against the block 9 with the fingers 11 open. At this time, due to the action of the parallel spring 19, the mask 4 can freely move parallel to the mask surface, so that the movement along the grooves is mutual and a smooth positioning and pressing operation is achieved.

In addition, since the shaft 20a of the adsorption member 20 is pushed back toward the main body 17 side in response to the pressing force of the mask 4 against the V-block and presses the leaf spring 22 to deform it, the resistance value of the strain cage changes and the bridge circuit etc. The pressing force is detected through the sensor. Based on the pressing force detected in this manner, it is possible to control the positioning pressing force by feedback controlling the pressure or weakening the pressing force during θ driving or mask adsorption.

FIG. 2 is a plan view of another embodiment of the invention. In this embodiment, as the rotation axis of the finger 11, an elastic thin hinge 25 is used in place of the fulcrum 13 in FIG. Instead, an elastic piece 28 and a thin hinge 27 each supported by a thin hinge are used.

The other configurations and effects are the same as those of the previous embodiment.

[Effects of the Invention] As explained above, the present invention has means for detecting external force on the mask, allows the mask to move freely parallel to the mask surface, and also allows the mask to be moved freely in parallel with the mask surface, and even in the open state of the mask hunt, the claw of the hand does not touch the mask. Since it is configured so that it does not come off from the groove on the side surface of the mask, it is possible to appropriately control the pressing force when positioning the mask, prevent the generation of dust due to friction, improve positioning accuracy, and protect the V block surface. In addition, positioning operations are performed smoothly and reliability is increased. Further, accidents such as falling of the mask during positioning or transportation are prevented.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the present invention, Fig. 2 is a plan view of another embodiment of the invention, Fig. 3(a),
(b) is an explanatory diagram of the open and closed fingers of the mask hand, respectively, FIG. 4 is a partially cross-sectional perspective view of the mask holding part, and FIG. 5 is the configuration of a mask conveying device to which the present invention is applicable. Figure 9 3: 8: 1 7 2 Mask hand, 4: Mask, Mask stage, 9: V block, : Finger, 12: Claw, 14: Groove, 2 bodies, 19: Parallel spring, ; Leaf spring, 23 : Strain gauge.

Claims (2)

[Claims] (1) A main body, two fingers provided on both sides of the main body that can be opened and closed, claws provided at the tips of the fingers for engaging with grooves on the side of the mask to be held, and a mask. The method further comprises a detection means for detecting an external force applied to the mask from the mask tip side to the main body side in a held state, and an elastic support means for holding the mask movably with respect to the main body parallel to the mask surface,
A mask holding device characterized in that the opening angle of the finger portion is limited so that the claw is engaged in a groove on a side surface of the mask when the finger portion is opened. (2) The mask holding device according to claim 1, wherein the external force detection means comprises an elastic member provided on the main body side that is deformed by the external force, and a strain gauge provided on the elastic member.