TW202412360A - Transfer method, photomask and display manufacturing method - Google Patents

Abstract

The present invention provides a transfer method and a photomask. The transfer device can achieve large-scale, fine-scale and short cycle time of the acceptor substrate while maintaining high transfer position accuracy. In a mechanism in which each stage group that moves in a state of holding a donor substrate on which a transfer object is placed and/or a beam shaping optical system and a reduced projection optical system, and a stage group that holds the acceptor substrate as the transfer target are constructed on separate platforms, the vibration generated by relative scanning of each substrate relative to a laser and the abnormality of the synchronization position accuracy of the stage that bears the scanning are minimized.

Description

Transfer method, mask and display manufacturing method

The present invention relates to a transfer method and a photomask, which use laser irradiation to transfer an object located on a donor substrate to a receptor substrate with high precision (LIFT: Laser Induced Forward Transfer).

Conventionally, there is a technology for irradiating an organic EL (electroluminescent) layer on a donor substrate with laser light and transferring it to an opposing circuit substrate. As such technology, Patent Document 1 discloses a technology in which a single laser light is converted into a plurality of rectangular laser lights having a uniform intensity distribution and arranged in series at equal intervals, and a predetermined area of the donor substrate is irradiated with the plurality of rectangular laser lights at intervals of a predetermined time or more and overlapped a predetermined number of times, so that the laser light is absorbed by a metal foil between the donor substrate and the organic EL layer to generate an elastic wave, and the organic EL layer peeled off thereby is transferred to the opposing circuit substrate.

This technology uses a structure in which a spacer having a suitable value of 80 to 100 [μm] is sandwiched between a donor substrate and a circuit substrate, and a member that keeps the distance between the donor substrate and the circuit substrate fixed and integrated is placed on a stage, and scanned relative to the laser. However, in this case, in addition to the need for a separate process to integrate the opposing donor substrate and circuit substrate, a donor substrate of the same size as the circuit substrate is required, and the circuit substrate needs to be enlarged, which increases the manufacturing cost and the size of the device.

Similarly, as a technology for transferring an organic EL layer on a donor substrate to an opposing circuit substrate, Patent Document 2 discloses the following technology: a light absorbing layer is provided between the donor substrate and the organic EL layer, and the light absorbing layer absorbs the irradiated laser light to generate a shock wave, thereby transferring the organic EL layer on the donor substrate to the opposing circuit substrate provided with a gap of 10 to 100 [μm]. However, Patent Document 2 does not disclose a laser scanning method and a stage structure for realizing the same, and does not disclose a transfer device. Therefore, Patent Document 2 cannot be used as a reference for maintaining and improving the transfer position accuracy that can correspond to the enlargement of the circuit substrate.

In addition, Patent Document 3 discloses a technology related to the step-and-scan method in an exposure device for semiconductor device manufacturing. The basic consideration is as follows: a row of irradiation areas along the scanning exposure direction of the wafer stage is exposed intermittently while skipping several irradiation areas in the middle, and the wafer stage is not stopped in the middle. That is, Patent Document 3 discloses an exposure device, which includes: an intermediate mask stage that holds the intermediate mask; a wafer stage that holds the wafer; and a projection optical system that projects the pattern of the intermediate mask onto the wafer, and exposes while the intermediate mask stage and the wafer stage are scanned relative to the projection optical system, and the pattern of the intermediate mask is sequentially projected onto multiple irradiation areas of the wafer, wherein multiple irradiation areas on the wafer arranged along the scanning direction are exposed intermittently while the wafer stage is scanned without being stationary. As a result, in response to the demand for larger wafers and faster processing speeds, the effects of vibration and shaking on exposure accuracy caused by stage scanning can be reduced compared to a step-and-repeat method that repeatedly accelerates and decelerates the wafer stage.

However, the technology disclosed in the above-mentioned Patent Document 3 is a technology of a semiconductor exposure device based on reduced projection exposure, and its technical field is different from the transfer technology of the present invention. That is, the structure and scanning technology of the intermediate mask stage and wafer stage of the exposure device are completely different from the stage structure and scanning technology of the present invention. The stage structure and scanning technology of the present invention are used to reduce and project the mask pattern of the present invention onto the object on the donor substrate with high positional accuracy, and then transfer the object to the receptor substrate with the same high positional accuracy. Therefore, as the specific stage structure and scanning technology of the present invention, the technology disclosed in the above-mentioned Patent Document 3 cannot be referred to.

Prior art literature

Patent document 1: Japanese Patent Publication No. 2014-67671

Patent document 2: Japanese Patent Publication No. 2010-40380

Patent document 3: Japanese Patent Publication No. 2000-21702

By configuring the donor stage for holding the donor substrate and the optical stage for holding the optical system placed on the donor stage as two stages independent of the receptor stage for holding the receptor substrate, and by configuring the optical stage not to be directly placed on the donor stage but to be independently provided on a high-rigidity platform, the influence of vibration and various errors caused by scanning of each stage on the synchronization position accuracy between the stages is minimized. As a result, the object of the present invention is to provide a transfer device that contributes to the enlargement, refinement and tact time reduction of the receptor substrate while maintaining the transfer position accuracy.

The first invention is a transfer device, which selectively peels off the object on the surface of the moving donor substrate by irradiating the object with pulsed laser from the back of the donor substrate, and transfers the object to a receiving substrate moving while facing the donor substrate, the transfer device comprising: a pulse oscillating laser device; a telescope, which makes the pulsed laser emitted from the laser device become parallel light; and a shaping optical system, which converts the pulsed laser passing through the telescope into a parallel light. The invention relates to a method for shaping the spatial intensity distribution of the laser into a uniform distribution; a mask, which allows the pulsed laser shaped by the shaping optical system to pass through in a prescribed pattern; a field lens, which is located between the shaping optical system and the mask; a projection lens, which projects the laser light of the pattern that has passed through the mask onto the surface of the donor substrate; a mask stage, which holds the field lens and the mask; an optical stage, which holds the shaping optical system, the mask stage and the projection lens; a donor stage, which allows the laser light to be shaped by the shaping optical system, the mask stage and the projection lens; and a donor stage, which allows the laser light to be shaped by the shaping optical system, the mask stage and the projection lens. The donor substrate is held in such a manner that the back side of the donor substrate becomes the incident side of the laser beam; a receptor stage is held to hold the receptor substrate; and a programmable multi-axis control device having a trigger output function and a stage control function for the pulse laser oscillation, the receptor stage having a Y axis when the horizontal plane is taken as the XY plane, a Z axis in the vertical direction, and a θ axis in the XY plane, the donor stage having an X axis, a Y axis, and a θ axis, the projection lens is held together with the Z axis stage for the projection lens On the optical table, the telescope, the shaping optical system, the field lens, the photomask and the projection lens constitute a reduced projection optical system, and the reduced projection optical system projects the pattern of the photomask on the surface of the donor substrate in reduced size. The X-axis of the donor table is set on platform 1 (first platform), and the Y-axis of the receptor table is set on platform 2 (second platform) different from platform 1, and the Y-axis of the donor table is suspended on the X-axis of the donor table.

Here, the "moving" substrate includes a situation where it moves without stopping even when irradiated with pulsed laser (indicated as "LS" in FIG. 1A. However, although FIG. 1A shows the main structural part of the second invention, it includes a structural part common to the structure of the first invention and is therefore used for reference. The same applies hereinafter) and a situation where it stops and repeatedly moves and stops when irradiated with pulsed laser. The above situation is selected according to the transfer process performed by the transfer device of the present invention and the required cycle time. In addition, a structure in which the donor substrate (D) repeatedly moves and stops and the acceptor substrate (R) does not stop and a structure in which the opposite situation is also included. When only one shot is used to peel the object from the donor substrate and a high cycle time is required, it is appropriate to select a structure in which the donor substrate and the acceptor substrate move continuously at the same or different speeds. On the other hand, when it is desired to stack the object layer to a certain thickness, it is sometimes desirable to select a structure in which the donor substrate moves continuously and the acceptor substrate stops for a certain number of shots.

In addition, the "object" is not particularly limited, and is a transfer object that is disposed on a donor substrate or disposed on a donor substrate in one piece via a light absorbing layer (not shown in FIG. 1A ), including thin films represented by the organic EL layer described in the patent document and multiple objects that are regularly arranged in a microscopic unit shape, but it is not limited to these objects. In addition, the transfer mechanism includes the following situations: the light absorbing layer irradiated with laser generates a shock wave, thereby the object is peeled off from the donor substrate and transferred to the receptor substrate; without a light absorbing layer, it is peeled off by the laser irradiated directly on the object; but it is not limited to these situations.

The material of the donor substrate only needs to have a transmission characteristic for the wavelength of the laser, and it is ideal to use a material with a small amount of bending caused by the enlargement of the substrate. In addition, when the amount of bending is so large that the uniformity of the gap between the donor substrate and the acceptor substrate is not satisfied, the method of holding the donor substrate on the donor stage (Yd, θd) includes the following methods: mechanical correction by setting an adsorption area near the center of the donor substrate, etc.; in addition, correction is performed using a gap sensor formed by a combination of height sensors described later.

In the present invention, in order to transfer an object located near the edge of the donor substrate to the acceptor substrate, the movable range of the donor stage includes the XY plane area where the donor substrate should be moved, and refers to a range that depends on the size of the acceptor substrate. As an example, when the size of the donor substrate in the XY plane is 200×200 [mm] and the size of the acceptor substrate is 400×400 [mm], the specified range where the donor stage (Xd, Yd) should be moved is approximately 800×800 [mm]. Figure 4 shows this situation. In addition, when further movement is required to remove the donor substrate, this area is also included.

In addition, there is no particular limitation on the material of the "platform", but it must be a material with extremely high rigidity. In order to make the platform 1 (G1) rigid, it is desired to have a "コ" shape or a "□" shape when viewed from above. In addition, in Figure 1A, the platform 2 is illustrated as a single shape, but specifically, it can also be configured as follows: the platform is provided as two platforms along the Y-axis direction, and a linear scale and a linear motor are placed in the middle. In addition, the platform 1 and the platform 2 can be a structure fixed on the same base platform (G). In addition, G1 can be composed of a combination of the platform 11 (G11) and the platform 12 (G12).

In addition, the material of any platform needs to be a high-rigidity member such as steel, stone, or ceramic material. For example, the stone material can be granite, but it is not limited to this. In addition, all platforms do not need to be made of the same material.

In the embodiments described later, the movement of each stage is described in detail, but the following actions are generally performed. First, the X-axis (Xd) of the donor stage is set on G1 in a state where the Y-axis (Yd) on which the donor stage is suspended is moved along the X-axis direction. In addition, this movement changes the relative position of the donor substrate and the acceptor substrate along the X-axis. FIG1B shows the movement. In addition, the detailed structure of the movable workbench and linear guide rail of the stage is not shown in any figure.

There is no limitation on the method of installing the optical table (Xo) on a platform, etc. Various mechanisms can be selected, such as a state of being placed on Xd, a state of being placed on the same platform as the platform on which Xd is installed, or a state of being placed on a platform different from Xd. Xo and Xd move simultaneously in the X-axis direction, and the relative positions of the shaping optical system (H), field lens (F), mask (M) and projection lens (Pl) do not change, so that they move as a whole. On the other hand, the movement of Xo along the X-axis changes the relative position relationship between the donor substrate and the projection lens. Figure 1C shows the movement.

In addition, when there is no need to change the relative position of the donor substrate and the projection lens in the X-axis direction, a structure that always moves with the X-axis of the donor stage can be used, that is, the optical stage is omitted, and the homogenizer, field lens, mask and projection lens are all arranged on the X-axis of the donor stage or fixed on another platform.

The mask is held on a mask stage, which has at least a W axis that moves along the X axis direction together with the field lens, and preferably, may also have: a U axis in the Y axis direction, a V axis that moves along the Z axis direction, an R axis that is a rotation axis in the YZ plane, a TV axis that adjusts the inclination relative to the V axis, and a TU axis that adjusts the inclination relative to the U axis. In addition, in order to suppress the injection of heat generated by irradiating the laser to the mask, a perforated mask may be provided on the front side of the eye of the mask, the perforated mask being configured with a pattern that is one circle larger than the mask pattern, and forming a double mask structure in combination with the mask.

The Y axis (Yd) of the donor stage and the Y axis (Yr) of the receptor stage move at the same or different speeds to keep the gap between the donor substrate and the receptor substrate fixed and maintain a very high degree of parallelism during the transfer process. In addition, according to the above-mentioned structure of the moving method of each stage group and the platform supporting them, by limiting the moving mechanism of the receptor substrate to the Y axis and separating it from the moving mechanism of the donor substrate, it is possible to suppress the mutual influence caused by interference and vibration of the moving areas of each substrate, and it is possible to cope with the increase in the size and refinement of the receptor substrate.

The second invention is based on the first invention, wherein the X-axis of the donor table is placed on the platform 1, and the optical table is placed on the X-axis of the donor table.

Fig. 1A shows the main structural part of the transfer device of the second invention (side view). Fig. 1B shows the situation where Xd is placed on Xo and moved from the state of Fig. 1A (side view). Fig. 1C shows the situation where Xo is moved on Xd from the state of Fig. 1B (side view). Fig. 1D shows a top view of Fig. 1C.

The third invention is based on the first invention, wherein the optical table is placed on the platform 1, and the X-axis of the donor table is suspended on the platform 1.

Fig. 2A shows the main structural part of the transfer device of the third invention (side view). Fig. 2B shows the situation where Xd and Xo move the same distance on G1 (Xd is suspended on G1) from the state of Fig. 2A (side view). Fig. 2C shows the situation where only Xo moves on G1 from the state of Fig. 2B (side view).

The fourth invention is based on the first invention, wherein the X-axis of the donor table is mounted on the platform 1, and the optical table is placed on a platform 3 (a third platform) which is different from both the platform 1 and the platform 2.

Here, "installed on the platform 1" includes a state of being placed on the platform 1 and a state of being suspended from the platform 1, but is not limited to these states.

The fifth invention is based on the first invention, and has a rotation adjustment mechanism between the X-axis of the donor table and the platform 1 for finely adjusting the setting angle between the two in the XY plane, and has a rotation adjustment mechanism between the X-axis of the donor table and the Y-axis of the donor table for finely adjusting the setting angle between the two in the XY plane.

Here, FIG. 3A shows an example of a rotation adjustment mechanism (RP) provided between the X-axis (Xd) of the donor table and the platform 1 (G1). In FIG. 3A, the left figure shows a top view, and the right figure shows a side view viewed from the X-axis direction. In addition, in the top view, the holes in the row on the outer side are used for fixing with G1, and have "play" (margin, leeway) in order to have a rotation adjustment function. In addition, in the top view, the holes in the two rows on the inner side are holes for passing screws, and the screws are used to fix the RP and the linear guide of Xd. In addition, the side with "play" can also be used as a hole for the linear guide of Xd, but when the two linear guides are fixed in an independent and parallel manner, there is a possibility that the difficulty of the setting process will increase.

On the other hand, FIG3B shows an example of RP provided between Xd and the Y axis (Yd) of the donor stage suspended from Xd. In the top view, the two rows of holes located on the outer side are used for fixing to Xd, and have "play" in order to have a rotation adjustment function. In addition, the two rows of holes arranged along the Y axis direction are used for fixing to Yd.

In addition, as the RP provided between G1 and Xd, an RP different from the aforementioned RP can be used. For example, a fulcrum (rotation axis in the Z-axis direction) is provided on the contact surface between the RP and G1, and the fulcrum is used to rotationally adjust the RP on which Xd is placed relative to G1 in the XY plane (illustration omitted), and a force point relative to the fulcrum is provided on the side surface (lead vertical surface) of the RP sufficiently away from the fulcrum. A large screw that pushes horizontally toward the force point is provided on G1 near the force point. Similarly, a large screw is provided on the side surface of the RP on the opposite side. Thus, the RP on which Xd is placed can be rotated relative to G1 in the XY plane at the order of microradians [μrad] with the fulcrum as the center.

The sixth invention is based on the second invention, and has a rotation adjustment mechanism between the X-axis of the donor table and the platform 1 for finely adjusting the setting angle between the two in the XY plane, a rotation adjustment mechanism between the X-axis of the donor table and the optical table for finely adjusting the setting angle between the two in the XY plane, and a rotation adjustment mechanism between the X-axis of the donor table and the Y-axis of the donor table for finely adjusting the setting angle between the two in the XY plane.

As the RP, for example, the RP used between G1 and Xd shown in FIG. 3A , the RP used between Xd and Xo shown in FIG. 3C , and the RP used between Xd and Yd shown in FIG. 3B can be used.

The seventh invention is based on the third invention, and has a rotation adjustment mechanism between the X-axis of the donor table and the platform 1 for finely adjusting the setting angle between the two in the XY plane, a rotation adjustment mechanism between the optical table and the platform 1 for finely adjusting the setting angle between the two in the XY plane, and a rotation adjustment mechanism between the X-axis of the donor table and the Y-axis of the donor table for finely adjusting the setting angle between the two in the XY plane.

Here, for example, the RP shown in FIG3A is used as the rotation adjustment mechanism between Xo and G1 and between Xd and G1, and the RP shown in FIG3B is used as the rotation adjustment mechanism between Xd and Yd. The former RP has holes through which screws for fixing the linear guides of Xo and Xd pass, and the "play" of the holes is used to adjust the setting angles in the XY plane of the RP and G1 to which the linear guides for each stage are fixed.

The eighth invention is based on the fourth invention, and has a rotation adjustment mechanism between the X-axis of the donor table and the platform 1 for finely adjusting the setting angle between the two in the XY plane, a rotation adjustment mechanism between the optical table and the platform 3 for finely adjusting the setting angle between the two in the XY plane, and a rotation adjustment mechanism between the X-axis of the donor table and the Y-axis of the donor table for finely adjusting the setting angle between the two in the XY plane.

The ninth invention is based on any one of the first to eighth inventions, wherein the laser device is an excimer laser.

Here, the oscillation wavelength of the excimer laser is mainly 193 [nm], 248 [nm], 308 [nm] or 351 [nm], and it is appropriately selected from them according to the material of the light absorbing layer and the light absorption characteristics of the object.

The tenth invention is based on the ninth invention, wherein the transfer device includes a pulse gate, and the pulse gate cuts off any pulse train of the laser pulse emitted from the excimer laser.

It is known that a pulse oscillating laser device receives a trigger signal from the programmable multi-axis control device and starts oscillating, but the energy of the pulse after a certain number of times or a certain period of time after the oscillation is unstable to the extent that it cannot be used depending on the application. Therefore, in order to eliminate the unstable pulse group, it is necessary to eliminate the above-mentioned pulse group through a mechanical photogate action. Specifically, in the case of an excimer laser oscillating at 1 [kHz], for example, the time window between adjacent laser pulses is about 1 [ms], and a high-speed photogate function that can move (traverse) a certain distance within this time is required. This certain distance depends on the size of the space where the laser beam is operated. If the distance is 5 [mm], the required speed of the shutter operation is 5 [m/s], and an ultra-high-speed shutter that uses a voice coil or the like to move the optical element in and out of the optical path is required. In addition, even if the size of the space is reduced by forming an optical system, the distance that the shutter component traverses can be shortened, but it is still easy to be damaged due to the energy density of the laser beam.

The eleventh invention is based on the tenth invention, wherein the programmable multi-axis control device has the function of at least simultaneously controlling the Y-axis of the recipient table and the Y-axis of the donor table, and includes a device for correcting the moving position error using pre-made two-dimensional distribution correction value data for correcting the moving position error of the table.

For example, the position of the acceptor substrate and the donor substrate during laser irradiation is corrected using two-dimensional distribution correction value data in the XY plane analogous to any combination of Xd or Xo and Yr or Yd. The main causes of the position error to be corrected include pitching, yawing, and rolling caused by the movement of each stage, but are not limited to these. In addition, the parameters for determining the correction value include the movement speeds of Yr and Yd and their ratio in addition to the position information of each stage.

The twelfth invention is based on the eleventh invention, wherein the high-magnification camera for monitoring the position of the donor substrate is arranged on the Z-axis of the acceptor stage, or the high-magnification camera for monitoring the position of the acceptor substrate is arranged on the X-axis of the donor stage or on the part moving together with the X-axis of the donor stage, or on the optical stage or on the part moving together with the optical stage.

Here, the "portion that moves with the X-axis of the donor stage" also includes Yd suspended from Xd. In the present invention, the parallelism between the Y-axes and the X-axes of each stage, as well as the perpendicularity between the Y-axis and the X-axis of each stage are important parameters for the accuracy of the left-right transfer position. In addition, in the inspection of the parallelism and perpendicularity when assembling each stage, the deviation in the direction perpendicular to the moving distance of each stage holding the alignment substrate is monitored using a high-magnification, high-resolution camera, and the perpendicularity is adjusted using the rotation adjustment mechanism. In addition, in the adjustment of the parallelism between Yr and Yd, the two stages are moved synchronously (in parallel) by the same distance, and the position of the alignment mark image (cross mark, etc.) attached to the opposing stage for pattern matching is observed by a high-magnification camera mounted on one stage to see if it does not move but remains stationary. In this case, the movement in the Y-axis direction indicates an abnormality in the synchronization of Yd and Yr, and the movement in the X-axis direction indicates an error in the adjustment of the parallelism of Yd and Yr.

In addition, a CCD camera is generally used as a high-magnification camera. The magnification and the like depend on the transfer position accuracy, but as an example, when detecting the deviation of the order of [μrad], that is, when detecting the deviation of 1 [μm] relative to the stage movement distance of 1 [m], a camera with a resolution of 1 [μm] and a magnification of about 20 to 50 times can be used.

The thirteenth invention is based on the twelfth invention, wherein the donor stage and the acceptor stage include a gap sensor, and the gap sensor measures the gap between the surface (lower surface) of the donor substrate and the surface of the acceptor substrate.

Here, the gap sensor refers to a sensor that combines height sensors respectively arranged on the donor stage and the receptor stage. The height sensor arranged on the donor stage measures the distance to the receptor substrate, and the height sensor arranged on the receptor stage measures the distance to the donor substrate. Based on the two measurement values and the height information of the height sensor, the gap between the donor substrate and the receptor substrate is calculated.

The fourteenth invention is based on the thirteenth invention, and includes a position measuring device using a laser interferometer as the Y axis of the acceptor stage and the Y axis of the donor stage.

As the structure of the laser interferometer for the Y axis (Yr) of the receptor stage, a structure including the following components can be used: a reflector (Ic) held on a portion that moves together with Yr; an interferometer laser (IL) fixed on a platform such as platform 2 (G2) that is not easily affected by vibrations caused by the movement; and a 1/4 wavelength plate, etc. (not shown). In addition, as the reflector, a three-axis pyramidal prism (retro-reflector) is suitable, and it is preferred to be located as close to the receptor substrate as possible (height). An overview is shown in FIG5A (illustration of the Z axis and θ axis of the donor stage group and the receptor stage is omitted).

Based on the position information from the linear encoder, Yr is controlled by a programmable multi-axis control device, and the laser interferometer is used for correction of the linear encoder and for correction when finely adjusting the gear ratio of Yr and Yd in the gear mode operation described later.

As the structure of the laser interferometer for the Y axis (Yd) of the donor stage, a structure including the following components can be used: Ic, which is held on a surface that moves together with Yd suspended on Xd; IL, which is fixed on Xd in the same manner; and a 1/4 wavelength plate, etc. (illustration omitted). Here, as the reflecting mirror, a three-axis pyramidal prism (retroreflector) is suitable, and the position (height) as close to the donor substrate as possible is preferred. An overview is shown in FIG5B. (The receptor stage group is omitted in the illustration) In addition, for the selection of the detection method of the laser for any interferometer, it is sufficient to select the most suitable method according to the required transfer position accuracy.

The fifteenth invention is based on the fourteenth invention, wherein the transfer device includes a confocal beam profiler having a focal plane at a position concentric with the position where the pattern of the mask is projected and imaged by the projection lens.

The confocal beam profiler can monitor the position and spatial intensity distribution of the laser light projected onto the donor substrate surface and its imaging state in real time and with the same accuracy as the imaging resolution of the reduced imaging optical system.

The sixteenth invention is a method for using a transfer device, wherein the transfer device is the transfer device of the thirteenth invention, and the gap sensor is used to pre-measure the bending amount of the donor substrate together with the XY position information of the donor substrate, and based on the two-dimensional distribution data of the bending amount obtained by the measurement, the gap between the donor substrate and the recipient substrate is corrected while being adjusted using the Z axis (Zr) of the recipient stage or the Z axis stage of the projection lens.

The seventeenth invention is a method for adjusting a transfer device, wherein the transfer device is the transfer device described in any one of the fifth to eighth inventions, and the method for adjusting the transfer device is a method for adjusting the parallelism of the Y axis of the acceptor stage and the Y axis of the donor stage in the process of assembling the transfer device. The method for adjusting the transfer device is based on the Y axis of the acceptor stage whose linearity is adjusted together with the Z axis and the θ axis of the acceptor stage, and sequentially comprises the following steps: using a rotation adjustment mechanism located between the platform 1 and the X axis of the donor stage, The verticality of the Y axis of the acceptor table and the X axis of the donor table is adjusted; the Y axis of the donor table suspended on the X axis of the donor table whose verticality is adjusted is made to move synchronously and in parallel with the Y axis of the acceptor table, and the alignment mark on the Y axis of the opposing donor table is observed by a high-magnification camera installed at a position moving together with the Y axis of the acceptor table; and based on the observation result, the parallelism of the Y axis of the acceptor table and the Y axis of the donor table is adjusted by a rotation adjustment mechanism between the X axis of the donor table and the Y axis of the donor table.

In order to accurately check and adjust the parallelism of Yd and Yr, it is preferred that the high-magnification camera be located at the highest position among the stages and plates placed on Yr and be mounted on a portion with high rigidity.

The present invention can realize the large-scale transfer device and the shortened cycle time of the receiver substrate based on the high synchronization position accuracy of the donor substrate and the receiver substrate while maintaining high transfer position accuracy.

Below, the specific structure of the transfer device of the present invention is described in detail with reference to the attached drawings.

[Example 1]

In the present embodiment 1, the following embodiment is shown: on a donor substrate of size 200×200 [mm], a layered (solid film) object formed as a single sheet with a light absorbing layer interposed therebetween is transferred as a unit-shaped transfer object each having a shape of 10×10 [μm] to a receptor substrate of size 400×400 [mm] in a matrix of 12000 in length and 12000 in width, totaling 144 million. The position accuracy of the above 144 million transfer positions is ±1 [μm], and the pitch of each length and width is 30 [μm].

First, FIG. 1A shows the main structural parts of the transfer device related to the implementation of the present invention. In addition, in FIG. 1A, the illustration of the laser device, the control device and other monitors is omitted, and the X-axis, Y-axis and Z-axis directions are as shown in the figure. Platform 1 (G1), platform 11 (G11), platform 12 (G12) and platform 2 (G2) are all stone platforms using granite. In addition, the base platform (G) uses high-rigidity iron. In addition, this embodiment is an embodiment based on the structure of the above-mentioned sixth invention.

The structure of the transfer device of Example 1 of the present invention is described in order of the transmission sequence of the laser from the laser device to the object on the donor substrate. First, the laser device used in Example 1 is an excimer laser with an oscillation wavelength of 248 [nm]. The spatial distribution of the emitted laser is about 8×24 [mm], and the beam divergence angle is 1×3 milliradian [mrad]. The above are all (vertical × horizontal) descriptions, and the values are FWHM.

In addition, there are various specifications of excimer lasers, and there are excimer lasers whose emitted lasers are longitudinally long (the longitudinal and transverse directions are reversed) due to differences in output, repetition frequency, beam size, and beam divergence angle, but there are various excimer lasers that can be used in this embodiment 1 by adding, omitting, or changing the design of the optical system. In addition, although the laser device depends on its size, it is generally installed on a base (laser stage) different from the base of the stage assembly on which the transfer device is installed.

The emitted light from the excimer laser enters the telescope optical system and is transmitted to the shaping optical system in front of it. Here, as shown in FIG. 1A, the shaping optical system is maintained on an optical table (Xo) in a manner such that the optical axis is along the X-axis, and the optical table is set on the X-axis (Xd) of the donor table that moves the donor substrate. In addition, the laser light just before entering the shaping optical system is adjusted by the telescope optical system in a manner such that it becomes substantially parallel light at any position within the X-axis movement range of the donor table. Therefore, regardless of the movement of Xd and/or Xo in the X-axis direction, the laser light always enters the shaping optical system with substantially the same size and the same angle (vertical). In the present embodiment 1, its size is approximately 25×25 [mm] (longitudinal × horizontal).

The shaping optical system (H) of this embodiment 1 combines two groups of uniaxial cylindrical lens arrays into two groups of right angles in a plane perpendicular to the optical axis direction. The configuration is as follows: the front-stage lens array in each group forms an image on the mask (M) through the rear-stage lens array and the focusing lens (not shown) located behind it.

The laser light that has passed through the shaping optical system is incident on the mask through the field lens (F) that forms the image side telecentric reduction projection optical system in combination with the projection lens (Pl). The size of the laser light on the mask is 1×50 [mm] (FWHM), and the size of the area where the spatial intensity distribution uniformity is within ±5% is maintained at 0.5×45 [mm] or more.

The mask is fixed on the mask stage. As mentioned above, the mask stage has a total of six-axis adjustment mechanisms, and the six axes are: the W axis that moves along the X-axis direction together with the field lens, the U axis in the Y-axis direction, the V axis that moves along the Z-axis direction, the R axis that serves as the rotation axis in the YZ plane, the TV axis that adjusts the inclination relative to the V axis, and the TU axis that adjusts the inclination relative to the U axis.

The mask of this embodiment 1 uses a mask with a pattern drawn (formed) on a synthetic quartz plate by chromium plating. Figure 6 shows an outline. In this mask, the window part (a) that is not chromium-plated and is represented by white passes through the laser, and the colored part (b) that is chromium-plated blocks the laser. The shape of one window (a) is 50×50 [μm], and a total of 300 are arranged in a row of 43.85 [mm] at intervals of 150 [μm] along the X-axis direction (one row). In addition, the chromium-plated surface is the emission side of the laser, and on the other hand, the incident side is provided with a reflection prevention film for 248 [nm]. In addition, instead of chromium plating, aluminum vapor deposition or a dielectric multilayer film can be used.

In addition, in the case of a transfer process in which a plurality of patterns are switched on one mask, masks with different patterns can be used if the size of the laser beam irradiated onto the mask from the shaping optical system is within the range and the movable range of the mask stage.

In addition, in FIG7, when a transfer process is used in which the donor substrate (D) is scanned multiple times or back and forth at the same speed while the receptor substrate (R) is scanned once (including stopping in the middle), the mask pattern shown in FIG6 may not be a single row, but a multi-row pattern (however, laser irradiation is intermittently and selectively irradiated in the mask pattern. FIG7 shows a matrix of 3×2 rows). This allows the use of a donor substrate that is smaller in size than the receptor substrate.

The laser light that has passed through the mask pattern is redirected by a mirror to face vertically downward (-Z direction) and enters a projection lens. The projection lens is provided with an anti-reflection film for 248nm and has a reduction ratio of 1/5. The details are shown in Table 1 below.

[Table 1] Projection lens detailed specifications Applicable wavelength [nm] 248 Projection surface size [mm] 1.0×15.0 Lens zoom factor 1/5 Resolution (line and space) [μm] 2 NA 0.13 Distance from mask to projection surface [mm] 1050

The laser light emitted from the projection lens enters from the back of the donor substrate and is accurately projected onto the predetermined position of the light absorbing layer formed on its surface (lower surface) at a scaled-down size of 1/5 of the mask pattern. Here, the predetermined position in the XY plane is determined by adjusting the X-axis (Xd), Y-axis (Yd), and θ-axis (θd) of the donor stage based on the alignment marks previously added to the donor substrate.

In order to adjust the image plane of the mask pattern generated by the projection lens to focus on the surface of the donor substrate and the edge interface of the light absorbing layer, adjust the position of the Z-axis stage (Zl) of the projection lens and the W-axis of the mask stage where the field lens (F) is placed. In addition, although the adjustment function of the Z-axis direction of the donor substrate can be added (Z-axis stage), it is necessary to consider the decrease in transfer position accuracy caused by adding a heavy load to the X-axis (Xd) of the donor stage.

When adjusting the imaging position of the edge interface between the donor substrate surface and the light absorbing layer, it is effective to use a confocal beam profiler (BP) with a plane on the focal plane that is conjugated with the image plane to monitor in real time. Figure 8 shows the adjustment screen. In this embodiment 1, the spatial intensity distribution of the laser light imaged at the edge interface between the donor substrate surface and the light absorbing layer is monitored in real time and with high resolution.

The above are the functions realized by the device structure of the present embodiment 1 related to the transmission of the pulse laser emitted from the laser device.

Next, it is briefly described how to use the structure of Example 1 in the device of the present invention to mechanically achieve the parallelism of the Y axis (Yr) of the receptor stage and the Y axis (Yd) of the donor stage.

As shown in FIG1A , the X-axis (Xd) of the donor stage is placed on the stone stage 1 (G1), and the optical stage (Xo) is placed on it. The acceptor stage group (Yr, θr, Zr) is placed on the stone stage 2 (G2). In addition, the entire structure is constructed on the base stage (G). In addition, the rotation adjustment mechanism (RP) is set between G1 and Xd, between Xo and Xd, and between Xd and Yd (not shown).

In addition, in order to adjust the verticality and parallelism of the axes of each stage, an adjustment substrate AD held on the donor stage is used instead of the donor substrate, and an adjustment substrate AR placed on the receptor stage is used instead of the receptor substrate. Lines representing the X axis (alignment line X) and the Y axis (alignment line Y) that form a right angle are drawn on either adjustment substrate as alignment lines, and marks are also added at predetermined positions (intervals).

1) Parallelism between Yr and AR (Y) (perpendicularity between Yr and AR (X))

In order to adjust the parallelism between the Y axis (Yr) of the receptor stage and the alignment line Y on the adjustment substrate AR, the adjustment substrate AR placed on the Z axis (Zr) of the receptor stage is observed by a high-magnification CCD camera fixed on the optical table (Xo) or on the Z axis stage for the projection lens of the optical table (Xo). The Yr axis is moved 400 [mm] to adjust the alignment line Y in the X axis direction within 1 [μm] using the θ axis (θr) of the receptor stage. In addition, the moving distance of the stage at this time is within the effective stroke range of the stage, and the allowable deviation varies depending on the required transfer accuracy. (The same applies hereinafter)

2) Parallelism between AR (X) and Xd (perpendicularity between Yr and Xd)

Next, the alignment line X of the adjustment substrate AR adjusted in the above manner is used to adjust the perpendicularity of the X axis (Xd) of the donor stage and the Y axis (Yr) of the receptor stage while observing with a high-magnification CCD camera, which is also fixed on the optical table (Xo) or installed on the Z axis table for the projection lens of the optical table (Xo). The Xd axis is moved 400 [mm], and the mounting angle of the two is adjusted using the rotation adjustment mechanism between G1 and Xd so that the deviation amount of the alignment line X in the Y axis direction is within 1 [μm], and the mounting angle of G1 and Xd, that is, the mounting angle of Xd relative to Yr is adjusted.

3) Parallelism between AR (X) and Xo (perpendicularity between Yr and Xo, parallelism between Xd and Xo)

Using the alignment line X of the adjustment substrate AR adjusted in the above manner, the parallelism of the optical table (Xo) and the X-axis (Xd) of the donor table is adjusted while being observed by a high-magnification CCD camera, wherein the high-magnification CCD camera is fixed to the optical table (Xo) or is disposed on the Z-axis table for the projection lens of the optical table (Xo). The Xo axis is moved by 200 [mm], and the parallelism of the optical table (Xo) relative to the X-axis (Xd) of the donor table is adjusted by a rotation adjustment mechanism between the two so that the deviation amount of the alignment line X in the Y-axis direction is within 0.5 [μm].

4) Parallelism between Yd and AD (Y)

In order to adjust the parallelism between the Y axis (Yd) of the donor stage and the alignment line Y on the adjustment substrate AD, the adjustment substrate AD held on the θ axis (θd) of the donor stage is observed by a high-magnification CCD camera fixed to the optical table (Xo) or installed on the Z axis stage for the projection lens of the optical table (Xo). The Yd axis is moved 200 [mm], and the θ axis (θd) of the donor stage is used to adjust so that the deviation of the alignment line Y in the X axis direction is within 0.5 [μm].

5) Parallelism between AD (X) and Xo (Parallelism between AD (X) and Xd, Perpendicularity between Xd and Yd)

In order to adjust the perpendicularity between the X-axis (Xd) of the donor stage and the Y-axis (Yd) of the donor stage, the alignment line X on the substrate AD is observed and adjusted by a high-magnification CCD camera fixed to an optical table (Xo) whose parallelism with the X-axis (Xd) of the donor stage has been adjusted or to a Z-axis table for a projection lens set on the optical table (Xo). The optical table (Xo) is moved 200 [mm], and the perpendicularity with the Y-axis (Yd) of the donor stage suspended on the X-axis (Xd) of the donor stage is adjusted by a rotation adjustment mechanism between the two so that the deviation amount of the alignment line X in the Y-axis direction is within 0.5 [μm].

6) Parallelism between AD (Y) and Yr (Parallelism between Yd and Yr)

Finally, in order to check the parallelism between the Y axis (Yd) of the donor stage and the Y axis (Yr) of the receptor stage, a high-magnification CCD camera is mounted on the Y axis (Yd) of the donor stage, and the alignment line Y of the adjustment substrate AR placed on the opposing receptor stage is observed. At this time, the adjustment substrate AD is removed in advance. The X axis (Xd) of the donor stage is moved so that the high-magnification CCD camera can observe either end of the receptor stage. Next, the Y axis (Yd) of the donor stage is moved 400 [mm] to check whether the deviation of the alignment line Y in the X axis direction is within 1 [μm]. In order to perform the same check on the other end of the receptor stage, after moving Xd to the other end, move Yd 400 [mm] to check that the deviation in the X-axis direction of the alignment line Y is within 1 [μm]. Alternatively, Yd and Yr may be moved in parallel to observe the position change of the alignment mark.

In addition, when the high-magnification CCD camera is mounted on the Y axis (Yd) of the donor stage, there is a possibility that the high-magnification CCD camera comes into contact with the position of the X axis of the donor stage and the shape (opening) of the stone platform 1. In this case, the high-magnification CCD camera is mounted on the Z axis (Zr) of the acceptor stage instead of Yd, and the Y axis (Yr) of the acceptor stage is moved by 200 [mm], so that the alignment line Y of the adjustment substrate AD can be observed and the amount of deviation in the X axis direction can be confirmed.

Since the stone platform 1 (G1) and the stone platform 2 independently support each stage, and Yd is suspended from Xd installed on G1, although the parallelism of Yr and Yd cannot be adjusted directly, the parallelism of Yr and Yd can be adjusted step by step in the order of [μrad] as described above. In addition, since the error of parallelism (perpendicularity) accumulates according to the adjustment steps in the order of 1) to 6), it is ideal to adjust in a way that the allowable deviation amount in the initial stage is suppressed to the minimum possible. In addition, although the adjustment steps 1) to 6) describe the adjustment of the parallelism and perpendicularity of each stage in the XY plane, it is also necessary to adjust the other axes (X axis and Y axis).

Next, referring to Figures 9A to 9C, the scanning of the donor substrate and the receptor substrate during transfer in this embodiment 1 is described. Here, the top view of Figures 9A to 9C is a diagram in which the operator is located on the left side of these figures and the donor substrate (D) and the receptor substrate (R) are scanned in the front and back direction relative to the operator.

First, the bending amount of the donor substrate adsorbed and set on the θ axis (θd) of the donor stage is measured over the entire surface of the donor substrate and mapped together with the position information as two-dimensional data. This information is used as the correction amount of the Z axis (Zr) of the acceptor stage corresponding to the X axis (Xd) and Y axis (Yd) of the donor stage moved in the transfer process.

In the following description, for the sake of convenience, the predetermined position in front of the left eye of the acceptor substrate (R) and the donor substrate (D) when viewed from the operator is defined as the origin of each substrate. In addition, the positions of the optical stage (Xo) and the acceptor stage (Yr, θr) when the laser is irradiated to the origin of the acceptor substrate are defined as the origins, respectively. In addition, in the donor substrate, the positions of the donor stage (Xd, Yd, θd) when the laser (LS) is irradiated are also defined as the respective origins. However, the origin of each stage is not limited to one end of its stroke range, but is a position where a portion of the stroke is left for movement for the subsequent transfer process and removal of the substrate.

FIG9A shows the initial pulse of laser (LS) irradiating the donor substrate (D) and the receptor substrate (R) at the origin. Here, both the side view (side view) and the top view (top view) are shown. The dotted line shows that the laser is irradiated to the object (S) through the reduced projection optical system, and the light absorption layer (not shown) in the 10×10 [μm] area receiving the irradiation absorbs the laser, ablates (ablation) and generates a shock wave, thereby transferring the object in the same area to the opposite receptor substrate. Although three objects are shown in the figure, in the case of this embodiment 1, a total of 300 objects are transferred to the receptor substrate at one time.

In the first embodiment, the laser device oscillates at 200 [Hz], and since the transfer is performed after one irradiation, the receptor stage (Yr) scans in the -Y direction at a speed of 6 [mm/s] without stopping the receptor substrate until the next irradiation position.

On the other hand, the Y axis (Yd) of the donor stage is synchronized with the Y axis (Yr) of the receptor stage, and the donor substrate is scanned at a speed of 3 [mm/s] in the same -Y direction without stopping. That is, the moving speed ratio (gear ratio) of Yd and Yr is 1:2. FIG9B shows the second irradiation after each substrate is moved.

With Yr as the master and Yd as the slave, the positions of Yr and Yd are synchronized by making the two stages perform gear pattern synchronization using the stage system's gear instructions. A programmable multi-axis control device is used in the control system.

In addition, in order to determine the gear ratio of the gear instruction, the actual measurement value of the stage position measured by the laser interferometer is used. A pyramidal prism (Ic) is installed, and a helium-neon (He-Ne) laser (IL) with a wavelength of 632.8 [nm] and a light receiving unit (not shown in FIG. 5A) are set on the stone platform 2 (or an equivalent fixed position). The pyramidal prism (Ic) moves together with the moving stage of Yr and constitutes a laser interferometer near the receptor substrate. Similarly, a pyramidal prism is installed on the side of the moving stage of Yd, and the interferometer laser and light receiving unit (not shown in FIG. 5B) are set on Xd. In this way, accurate position synchronization of each stage is achieved.

As described above, each stage starts accelerating from the position on the front side of the origin in a manner that has become a stable constant speed motion. During this acceleration time and the time until the stage reaches the origin, the laser pulse needs to be cut off so that the laser does not irradiate the donor substrate. Therefore, an external oscillation trigger signal or a high-speed photogate action start trigger signal and a stage drive signal are sent to the laser device with high precision from a programmable multi-axis control device.

FIG9C shows the third irradiation. It can be seen from the figure that the moving distance of the acceptor substrate (R) is twice the moving distance of the donor substrate (D). After that, the acceptor substrate and the donor substrate continue to move in the same way.

When the donor substrate is scanned 180 [mm] in the -Y direction and ends, similarly, when the receptor substrate is scanned 360 [mm] in the -Y direction and ends, the oscillation of the laser device is temporarily stopped, or the laser irradiation is cut off by a high-speed light gate. By scanning this distance, 300 objects arranged in the X-axis direction are transferred 12,000 rows in the Y-axis direction of the receptor substrate, totaling 3.6 million objects. Figure 10 shows this situation.

During the stop time, the Y axis (Yr) of the recipient stage and the Y axis (Yd) of the donor stage return to the origin. (However, the acceleration distance of the next scan is taken into consideration. The same applies below.) On the other hand, the X axis (Xd) of the donor stage returns to a position of -9 [mm] compared to the previous origin. In addition, the transfer process starts again from a new area. The above actions are repeated below.

Figure 11 shows the situation before the -9[mm]×20-times step movement of Xd is completed and the position 15[μm] (shown by the solid line) is returned to the -X direction from the previous origin (shown by the dotted line) and the same movement is started with this point as the new origin. After that, the Y-axis scanning of the two stages (180[mm] (Yd) and 360[mm] (Yr)) and the -9[mm]×20-times step operation of Xd are repeated. Thus, by irradiating the area that has not been irradiated with the laser (the area scheduled for irradiation with the next laser (LS) is indicated by a single-point line in the figure) with the laser during the initial 180 [mm] scan of Xd (20 step movements of -9 [mm]), the object on the donor substrate can be transferred to the receptor substrate without waste and in larger quantities.

The approximate processing time is 360 [mm] / 6 [mm/s] × 40 [times] = 2400 [s]. In addition, this time does not include the time required for the Y-axis (Yr) of the receptor stage to move the distance required for acceleration and deceleration and the time required for each Y-axis scan to return to the origin. In addition, by increasing the repetition frequency of the excimer laser to 1 [kHz], the above processing time can be shortened by 1/5.

FIG12 shows the synchronous position error of the two stages when the Y axis (Yr) of the acceptor stage is used as the reference (master) and the acceptor stage is moved a distance of 400 [mm] at a moving speed of 150 [mm/s] in a synchronous manner, and the Y axis (Yd) of the donor stage is used as the slave and the donor stage is moved a distance of 200 [mm] at a moving speed of 75 [mm/s] by using the device structure of the present embodiment 1. Specifically, the error (δYr) between the position information obtained from the linear encoder on Yr, which is the reference (master), and the position information measured by the laser interferometer, and the error (δYd) between the position information obtained from the linear encoder on Yd, which is the slave (slave) moving synchronously at 1/2 of the above speed, are plotted as the elapsed time corresponding to the moving speed of the subject stage (ΔYdr = δYd-δYr). From the results, it can be seen that the position synchronization accuracy within ±1 [μm] is achieved within a moving distance of 400mm.

As described above, the transfer pattern of the object to the receptor substrate in Example 1 is to transfer 10×10 [μm] in a matrix at intervals of 30 [μm]. However, if the interval is set to 60 [μm], for example, four receptor substrates can be transferred using one donor substrate.

[Example 2]

In this embodiment 2, unlike the embodiment 1 in which the object on the surface of the donor substrate is in a layered state, the embodiment is as follows: a total of 144 million objects with a shape of 10×10 [μm] and a spacing of 15 [μm] formed in a matrix on a donor substrate of the same size of 200×200 [mm] are transferred to a receiving substrate of the size of 400×400 [mm] at a density of 1/2 of the donor substrate, i.e., at a spacing of 30 [μm] and in the same matrix.

Finally, the arrangement of the object to be transferred to the acceptor substrate is the same as in Example 1, but the difference is that in this Example 2, the object is also arranged on the donor substrate in advance at twice the density, and it is transferred to the acceptor substrate with a positional accuracy of ±1 [μm]. In addition, in this case, compared with Example 1, the position synchronization accuracy of the Y axis (Yd) of the donor stage and the Y axis (Yr) of the acceptor stage is more strictly required.

FIGS. 13A to 13C show the situation from the first pulse of laser (LS) irradiation to the third pulse irradiation on the donor substrate (D) and the receptor substrate (R) located at the origin position, similarly to Example 1. FIG.

[Example 3]

In the present embodiment 3, the method of transferring the object on the surface of the donor substrate to the acceptor substrate is the same as that of the embodiment 1 or the embodiment 2. On the other hand, the method of adjusting the parallelism between the Y axes of each stage and the parallelism between the X axes, and the perpendicularity between each Y axis and the X axis is different from the above embodiments. That is, the adjustment method described in the embodiment 1 is as follows: in order to adjust the parallelism between the Y axis (Yr) of the acceptor stage and the Y axis (Yd) of the donor stage, the adjustment steps 1) to 6) are performed, while in the present embodiment 3, the parallelism between the Yr and Yd is adjusted at the early stage of the adjustment step.

1) Straightness of Yr, θr, and Zr

This adjustment step is an adjustment step that is common to the above-mentioned Embodiment 1 and Embodiment 2. The Y axis (Yr) of the receptor stage set on the stone platform 2 (G2) and the θ axis (θr) set thereon, as well as the Z axis (Zr) and the straightness of the holder of the receptor substrate (the straightness of the Z axis relative to the vertical direction when the horizontal plane is the XY plane) are adjusted using a laser interferometer or the like. In addition, basically after this adjustment, no adjustment that may affect the verticality of the receptor stage group is performed, and all adjustments of other stages are performed based on, for example, the uppermost surface of the above-mentioned receptor stage group.

2) Parallelism between Yr and AR (Y) (perpendicularity between Yr and AR (X))

As in the adjustment step 1) of Example 1, the parallelism between the Y axis (Yr) of the receptor stage and the alignment line Y on the adjustment substrate AR is adjusted. Thus, the perpendicularity between Yr and the alignment line X is also adjusted. In addition, when the adjustment substrate AR is not used and an alignment line or alignment mark obtained by directly drawing on Yr is used, this adjustment step 1) can be omitted.

3) Parallelism between AR (X) and Xd (perpendicularity between Yr and Xd)

Next, the alignment line X of the substrate AR is observed and adjusted by a high-magnification CCD camera set on an optical table (Xo) placed on the X-axis (Xd) of the donor table. The position of the high-magnification CCD camera in the Z-axis direction is determined by the design of the projection optical system, but in this embodiment 3, a Z-axis table (Zl) holding the projection lens is fixed near the position of the projection lens (Pl). Xd is moved 400 [mm], and the installation angle of Xd relative to the stone table 1, that is, the verticality of Xd relative to Yr, is adjusted using a rotation adjustment mechanism so that the deviation amount of the alignment line X in the Y-axis direction is within 0.3 [μm].

4) Parallelism of Yr and Yd in the YZ plane

In the description of Example 1, the description of the adjustment steps of other axis systems (X axis and Y axis) is omitted. Here, the adjustment steps of the parallelism of the X axis system, that is, the YZ plane, are briefly described. The lower surface of the Y axis (Yd) of the donor stage is observed using a height sensor installed on the Z axis (Zr) or other parts of the recipient stage. Yr and Yd are moved synchronously (in parallel) at the same distance of more than 200 [mm], and the change of the measurement value (the distance between Zr and Yd) of the gap sensor is observed. In order to keep the change within 5 [μm] or within a sufficiently small range compared to the focal depth of the image formed by the projection lens, a pad is inserted into the rotation adjustment mechanism between Xd and Yd and between Yd or Xd to adjust the parallelism in the YZ plane between Yr and Yd.

5) Parallelism between Yr and Yd

The alignment mark for pattern matching provided on the lower surface of Yd is observed using a high-magnification CCD camera installed at Zr or other locations. When Yr and Yd are moved synchronously (in parallel) by the same distance and the position of the alignment mark image (cross mark, etc.) for pattern matching is moved along the X-axis direction, the rotation adjustment mechanism installed between Xd and Yd is used to adjust and correct it. In addition, instead of the alignment mark, the alignment line Y of the adjustment substrate AD installed on the Y-axis of the donor stage can also be used.

6) Perpendicularity between Yr and Xo

The alignment line X of the adjustment substrate AR whose perpendicularity to the Y axis (Yr) of the receptor stage was adjusted in the adjustment step 1) was observed by a high-magnification CCD camera installed on the optical stage (Xo). Xo was moved 400 [mm] so that the deviation of the alignment line X in the Y axis direction was within 0.3 [μm], and the mounting angle of Xo relative to Xd was adjusted using a rotation adjustment mechanism installed between the two.

[Example 4]

FIG. 2A shows the main structure of the transfer device of the present embodiment 4. This is an embodiment using the seventh invention of the present invention as a basic structure. In addition, in FIG. 2A to FIG. 2C, the illustration of the laser device, the control device, and other monitors, etc. (all of which are the same as those of the embodiment 1) is omitted, and the X-axis, Y-axis, and Z-axis directions are shown in the figure. In addition, the donor substrate, the acceptor substrate, and the arrangement of the transfer object on the donor substrate and the arrangement after the transfer to the acceptor substrate used in the present embodiment 4 are the same as those of the embodiment 2.

The optical system from which pulsed laser light is emitted from the excimer laser device to the transfer object on the donor substrate is as described below, and is the same as that of Embodiment 1 except for the difference in the construction of each stage assembly shown in FIG. 1A and FIG. 2A. That is, in the case of the transfer device of the sixth invention shown in FIG. 1A to FIG. 1C, the X axis (Xd) of the donor stage is sequentially arranged on the stone stage 1 (G1) and the optical stage (Xo) is arranged thereon, whereas in the case of the transfer device of the seventh invention shown in FIG. 2A to FIG. 2C, the difference in the construction of these stage assemblies is that Xo is placed on G1 and Xd is suspended below G1.

The emitted light from the excimer laser enters the telescope optical system and propagates to the shaping optical system in front of it. As shown in Figure 2A, the above-mentioned shaping optical system is set parallel to its optical axis on an optical table (Xo) moving in the X-axis direction. In addition, Xo is placed on a stone platform 1 (G1) made of granite, and there is a rotation adjustment mechanism (RP) between the two. Here, Xo is at right angles to the Y axis (Yr) of the receptor table placed on a stone platform 2 (G2) different from G1, and is parallel to the X axis (Xd) of the donor table. In addition, the laser light before entering the shaping optical system is adjusted by the telescope optical system to a substantially identical shape (approximately 25×25 [mm] (vertical × horizontal, FWHM)) regardless of the movement of Xo.

The X-axis (Xd) of the donor table is suspended below G1, and the Y-axis (Yd) of the donor table is also suspended. In addition, there is a rotation adjustment mechanism between them. FIG2B shows a case where Xo and Xd move the same distance relative to G1 by a side view. Thus, the position of X-axis direction relative to Yd can be changed without changing the relative position of Xo and Xd on the X-axis. In addition, FIG2C shows a case where only Xo moves relative to G1 by a side view. Thus, the relative position of Xd and Xo on the X-axis can be changed.

The details of the field lens (F), mask (M) and projection lens (Pl) as other reduction projection optical systems are the same as those in Example 1. The laser light emitted from the projection lens enters from the back of the donor substrate and is accurately projected toward the transfer object formed on its surface (lower surface) at a reduced size of 1/5 of the pattern drawn on the mask. In addition, the imaging on the surface of the donor substrate is performed by a confocal beam profiler as in Example 1.

Based on the mask pattern that is projected in scale onto the transfer object arranged on the surface of the donor substrate in the manner described above, when the transfer object is transferred to the opposite receiver substrate, the manner in which the donor substrate and the receiver substrate are scanned and the manner in which the transfer object is transferred to the receiver substrate is the same as that in Figures 6, 10, 11 and 13A to 13C. In addition, the position synchronization accuracy of the movement of the Y-axis (Yr) of the receiver stage and the Y-axis (Yd) of the donor stage is the same as that in Figure 12 described in Example 1.

In addition, the method for adjusting the parallelism between the Y axes of each stage and the parallelism between the X axes, and the perpendicularity between each Y axis and the X axis is the same as that in Example 3. That is, the Y axis (Yr) of the acceptor stage whose straightness has been adjusted is used as the reference for adjustment, and the perpendicularity between Yr and the X axis (Xd) of the donor stage suspended from the stone stage 1 (G1) is observed by a high-magnification CCD camera fixed to the Z axis (Zr) of the acceptor stage, and adjustment is performed by a rotation adjustment mechanism (RP) between G1 and Xd. In addition, the parallelism between the Y axis (Yd) of the donor stage suspended on the adjusted Xd and Yr is observed by the same high-magnification CCD camera, and adjustment is performed by RP between Xd and Yd. Finally, the perpendicularity between the optical table (Xo) and Yr is observed by a high-magnification CCD that moves with Xo and adjusted by the RP between G1 and Xo.

[Industrial Practicality]

The present invention can be used as a manufacturing device for a display.

1: Platform 2: Platform 3: Platform 11: Platform 12: Platform AD: Adjustment substrate for donor stage AR: Adjustment substrate for receptor stage BP: Confocal beam profiler CCD: High magnification camera D: Donor substrate F: Field lens G: Base platform G1: Platform 1 G11: Platform 11 G12: Platform 12 G2: Platform 2 G3: Platform 3 H: Shaping optical system Ic: Cone prism for laser interferometer IL: Laser for laser interferometer LS: Laser M: Mask Pl: Projection lens R: Receptor substrate RP: Rotation adjustment mechanism S: Object TE: Telescope Xd: X axis of donor stage Xo: Optical stage (X axis) Yd: Y axis of donor stage Yl: Switching stage for projection lens and camera Yr: Y axis of acceptor stage Zl: Z axis stage for projection lens Zr: Z axis of acceptor stage θd: θ axis of donor stage θr: θ axis of acceptor stage

FIG. 1A shows the main structural part of the transfer device of the present invention (side view). (Second invention) FIG. 1B shows the X-axis of the donor table when the optical table is placed and moved from the state of FIG. 1A (side view). FIG. 1C shows the optical table when it is moved on the X-axis of the donor table from the state of FIG. 1B (side view). FIG. 1D is a top view of FIG. 1C. FIG. 2A shows the main structural part of the transfer device of the present invention (side view). (Third invention) FIG. 2B shows the X-axis of the donor table and the optical table when they are moved the same distance on the platform 1 from the state of FIG. 2A (side view). FIG2C shows a case where only the X-axis of the optical table is moved on the stage 1 from the state of FIG2B (side view). FIG3A shows an example of a rotation adjustment mechanism used between G1 and Xd. FIG3B shows an example of a rotation adjustment mechanism used between Xd and Yd. FIG3C shows an example of a rotation adjustment mechanism used between Xd and Xo. FIG4 shows the range in which the donor stage should be moved according to the size of the receptor substrate. FIG5A shows a case where a Y-axis laser interferometer is provided with a receptor stage. FIG5B shows a case where a Y-axis laser interferometer is provided with a donor stage. FIG6 shows an example of a pattern formed on a mask. FIG7 shows a case of a transfer process using a multi-row mask pattern. FIG8 shows the monitoring of the confocal beam profiler. FIG9A shows the first irradiation of the transfer process. FIG9B shows the second irradiation of the transfer process. FIG9C shows the third irradiation of the transfer process. FIG10 shows the condition of the acceptor substrate after being scanned once with a gear ratio of 1:2. FIG11 shows the step scanning of the X axis of the donor stage. FIG12 shows the synchronous position error when the Y axis of the acceptor stage and the Y axis of the donor stage are moved in parallel. FIG13A shows the first irradiation of the transfer process using a matrix-shaped donor substrate. FIG13B shows the second irradiation of the transfer process using a matrix-shaped donor substrate. FIG13C shows the third irradiation of the transfer process using a matrix-shaped donor substrate.

BP: Confocal Beam Profiler

CCD: high magnification camera

D: Donor substrate

F: Scene lens

G: Basic platform

G1: Platform 1

G11: Platform 11

G12: Platform 12

G2: Platform 2

H: Shaping optical system

LS: Laser

M: Mask

Pl: Projection lens

R: Receptor substrate

TE:Telescope

Xd: X axis of the donor platform

Xo: Optical table (X axis)

Yd: Y axis of the donor platform

Yl: Switching table for projection lens and camera

Yr: Y axis of the receptor stage

Zl: Z-axis stage of projection lens

Zr: Z axis of the receptor stage

θd: θ axis of the donor stage

θr: θ axis of the receptor stage

Claims (22)

A transfer method is a method of projecting a laser-radiated mask pattern from the back side of a substrate onto an object disposed on the surface of the substrate, so that the object is peeled off from the substrate and the object is transferred to another substrate. The mask pattern is obtained by irradiating the mask with the laser. The mask has a plurality of window portions through which the laser is transmitted. The plurality of window portions are spaced apart and arranged. A transfer method as described in claim 1, wherein the multiple window portions are configured in a row. A transfer method as described in claim 1, wherein the multiple window portions are configured into multiple columns. A transfer method as described in claim 1, wherein the multiple window parts are configured in a matrix shape. A transfer method as described in any one of claims 1 to 4, wherein the shape of the laser on the mask is a shape covering multiple window portions separating the spacer configuration. A transfer method as described in any one of claims 1 to 5, wherein the shape of the laser on the mask is linear. A transfer method as described in any one of claims 1 to 4, wherein the relative position of the substrate and the other substrates is moved. A transfer method as described in claim 7, wherein the relative position of the substrate and the mask pattern of the laser irradiated on the substrate is moved. A transfer method as described in any one of claims 1 to 4, wherein the substrate and the other substrates move at different speeds relative to the mask pattern of the laser irradiated on the substrate. A transfer method as described in claim 7, wherein the movement is stopped when the laser is irradiated toward the substrate. A transfer method as described in claim 9, wherein the movement is stopped when the laser is irradiated toward the substrate. A transfer method as described in claim 7, wherein the movement is not stopped when the laser is irradiated toward the substrate. A transfer method as described in claim 9, wherein the movement is not stopped when the laser is irradiated toward the substrate. A photomask is used in a transfer method for projecting a laser-radiated mask pattern from the back side of a substrate onto an object disposed on the surface of the substrate, so that the object is peeled off from the substrate and the object is transferred to another substrate. The photomask has a plurality of window portions through which the laser is transmitted, and the plurality of window portions are spaced apart and arranged. A photomask as described in claim 14, wherein the plurality of window portions are arranged in a row. A photomask as described in claim 14, wherein the plurality of window portions are arranged in a plurality of rows. A photomask as described in claim 14, wherein the plurality of window portions are arranged in a matrix shape. A photomask as described in any one of claims 14 to 17, which is used in a method for transferring the relative positions of the substrate and the other substrates. The photomask as described in claim 18 is used in the following transfer method: Moving the relative position of the substrate and the photomask pattern of the laser irradiated on the substrate. A photomask as described in any one of claims 14 to 17, which is used in the following transfer method: Relative to the photomask pattern of the laser irradiated on the substrate, the substrate and the other substrates move at different speeds. A method for manufacturing a display, comprising a transfer process using the transfer method as described in any one of claims 1 to 13. A method for manufacturing a display as described in claim 19, wherein the other substrate is a circuit substrate.