JP2013131577A5 - - Google Patents

Description

The present invention is an imprint apparatus for forming a pattern using a mold on an imprint material on a substrate, the substrate holding section for holding the substrate, the mold is held, and the mold is placed on the imprint material. A mold holding part that is movable in the first direction so as to be brought into contact with the mold and that can tilt the mold with respect to a plane orthogonal to the first direction, and detects a position of the mold holding part in the first direction. a first detector, a second detector for detecting a position in the second direction perpendicular to the first direction of the die holding unit, and a tilt detection unit that detects a tilt of the mold, said first detector And a control unit that controls a position of at least one of the substrate holding unit and the mold holding unit in the second direction based on detection results of the second detection unit and the inclination detection unit. Imprint device.

The OA scope 14 can measure the coordinates X and Y indicating the shot position by detecting a mark formed on the wafer 5 at a position away from the mold 3. Since the OA scope 14 has fewer arrangement space restrictions than the TTM scope 13, the OA scope 14 can have many functions (process-corresponding functions) for switching detection conditions such as the wavelength of light used for mark detection. Further, global alignment measurement can be performed using the OA scope 14. By detecting the positions (shifts) of the marks of a plurality of sample shots on the wafer 5, it is possible to determine the wafer shot arrangement (position of each shot).

Thereafter, the imprint head 4 is driven in the Z-axis direction (raised in the Z-axis direction) , and the mold is released from the cured imprint material (the interval between the imprint material and the mold is increased) . Thereby, a mold pattern can be formed (transferred) on the imprint material on the substrate. This series of operations is performed for all shots on the wafer 5. Here, the alignment between the mold and the wafer (shot) is performed by measuring the position (X, Y coordinates) of the imprint head. A detailed description of the alignment will be described later.

Therefore, the imprint apparatus 1 includes a sensor 16 (head position detection unit , second detection unit ) for measuring the position of the imprint head 4. For example, the position of the imprint head 4 is measured using a laser interferometer as the sensor 16 and a mirror 24 with high flatness provided in the imprint head 4. The mirror 24 is disposed or formed on the side surface of the imprint head 4. The laser interferometer uses the light reflected by the mirror 24 to measure the position in the direction (second direction) orthogonal to the moving direction (Z axis , first direction ) of the imprint head 4. In FIG. 2, the position of the imprint head 4 in the X-axis direction is measured. Based on the measurement result, the position of the wafer stage is finely adjusted to prevent the overlay accuracy from being lowered due to the positional deviation of the imprint head.

The surface of the wafer 5 has a certain degree of unevenness. When the surface of the wafer is observed in shot units, it may be inclined with respect to the surface on which the mold pattern is formed. For this reason, the imprint head 4 can be tilted so that the surface of the mold 3 follows the surface of the wafer 5 (globally parallel) through the contact between the resin 18 on the wafer 5 and the mold 3. (Includes a mechanism that allows tilting). Alternatively, when the inclination of the surface of the wafer is known in advance , the resin 18 on the wafer and the mold may be brought into contact by inclining the imprint head in accordance with the inclination of the wafer. In that case, the imprint apparatus has a drive mechanism for tilting the imprint head 4. Further, a tilt sensor 22 ( tilt detection unit) is provided for detecting the tilt (tilt angle) of the imprint head 4 (mold 3) . Further, a drive mechanism that rotates the imprint head 4 about the X axis and the Y axis as rotation axes is included. A drive mechanism that rotates the imprint head 4 about the Z axis as a rotation axis may be included.

The Abbe error caused by the tilt of the imprint head 4 will be described with reference to FIG. The imprint head 4 can move in the direction of the arrow 19 (first direction) and can tilt with respect to a plane orthogonal to the first direction. A case where the mold 3 and the resin 18 come into contact with each other when the imprint head 4 moves in the direction of the arrow 19 (first direction) will be described. When the mold 3 comes into contact with the resin 18, the mold 3 is inclined in accordance with the inclination of the substrate 5 on which the shot 17 is formed . Therefore, the imprint head 4 that holds the mold 3 is inclined.

Wafer stage 6 holds wafer 5 on which a mark for a TTM scope is formed. The imprint head 4 holds a mold 3 on which a mark for a TTM scope is formed. In this state, alignment is performed using the mark formed on the wafer 5 and the mark formed on the mold 3. Here, the description will be made using the mark formed on the wafer 5, but a reference mark provided on the wafer stage 6 may be used instead of the mark formed on the wafer 5. In order to be able to measure the mark using the TTM scope 13, the position of the imprint head 4 in the Z-axis direction is adjusted to adjust the distance between the wafer 5 and the mold 3. At this time, it is desirable that the surface of the mold 3 on which the mark is formed and the surface of the wafer 5 are parallel. The position in the Z-axis direction of the imprint head at this time is assumed to be Z0. The imprint apparatus includes a head height detector ( not shown ) (first detector) , and can measure the height of the imprint head 4.

However, when the imprint head 4 is tilted, as shown in FIG. 4, the value of the sensor 16 that measures the position of the imprint head changes due to the influence of the Abbe error. The imprint apparatus includes a tilt sensor 22 that detects the tilt amount of the imprint head 4 in addition to the sensor 16 that detects a change in the position of the imprint head 4 on the XY plane. The tilt sensor 22 can detect the tilt (angle) of the imprint head 4 in the X direction and the Y direction. This can be substituted by arranging a plurality of Z-direction measurement sensors (not shown) on the X-axis or Y-axis of the imprint head. Alternatively, a plurality of imprint head position measurement sensors 16 may be arranged in the Z direction. If the inclination amount of the imprint head can be detected, the sensor configuration is not questioned. When the measurement values of both the TTM scope 13 and the sensor 16 change, the change in the measurement value in the TTM scope 13 is added to the change in the measurement value in the sensor 16. That is, the change in both values is added or subtracted. Whether to add or subtract depends on the sign of the measured value of each sensor.

In this embodiment, a case where imprinting is performed at a shot position obtained using the global alignment method will be described. The imprint head 4 also needs to be inclined due to the inclination of the wafer surface. At this time, the Abbe error is included in the detection result of the sensor 16 that detects the position of the imprint head 4 in the second direction (first detection). Therefore, the wafer stage 6 erroneously corrects the follow-up as shown in FIG.

In order to correct this measurement error, the inclination ( inclination amount ) of the imprint head 4 (mold 3 ) is detected using the inclination sensor 22 during the imprint operation (second detection). Further, the height (position in the first direction) of the imprint head 4 in the Z-axis direction is also detected (third detection). A measurement error (ΔX) of the sensor 16 is obtained using an Abbe coefficient (C) that varies depending on the detected tilt amount (Tx) and the height in the Z-axis direction. The measured value of the sensor 16 is corrected using the obtained measurement error value.

Claims (8)

An imprint apparatus for forming a pattern using a mold on an imprint material on a substrate,
A substrate holder for holding the substrate;
A mold holding unit that holds the mold, is movable in a first direction so as to contact the mold with the imprint material, and can tilt the mold with respect to a plane orthogonal to the first direction;
A first detection unit that detects a position of the mold holding unit in the first direction;
A second detection unit that detects a position of the mold holding unit in a second direction orthogonal to the first direction;
A tilt detection unit that detects a tilt of the mold,
A control unit that controls a position of at least one of the substrate holding unit and the mold holding unit in the second direction based on detection results of the first detection unit, the second detection unit, and the inclination detection unit; An imprint apparatus comprising: The said control part controls the position in the said 2nd direction of at least one of the said board | substrate holding part and the said mold holding part so that alignment with the said board | substrate and the said mold | type is made. 2. The imprint apparatus according to 1. The control unit obtains an Abbe coefficient of the second detection unit based on a position of the mold holding unit in the first direction, and an Abbe error of the second detection unit based on the Abbe coefficient and the inclination of the mold. The imprint apparatus according to claim 1, wherein the detection result of the second detection unit is corrected with the Abbe error. The said control part hold | maintains the information for calculating | requiring the Abbe coefficient of the said 2nd detection part from the position in the said 1st direction of the said mold | type holding | maintenance part, The Claim 1 characterized by the above-mentioned. The imprint apparatus described.   The imprint apparatus according to claim 4, wherein the control unit holds information for obtaining the Abbe coefficient from a position of the die holding unit in the first direction and a thickness of the die. A mold holding unit that is movable in a first direction so that the mold is brought into contact with the imprint material on the substrate held by the substrate holding unit and that can tilt the mold with respect to a plane orthogonal to the first direction. using retained the type, a imprint method for forming a pattern on the imprint material on the substrate,
Performing a first detection for detecting a position of the mold holding portion in a second direction orthogonal to the first direction;
Performing a second detection to detect the tilt of the mold;
Performing a third detection for detecting the position of the mold holding portion in the first direction;
An imprint method comprising controlling a position of at least one of the substrate holding part and the mold holding part in the second direction based on the results of the first to third detections. Forming a pattern on a resin on a substrate using the imprint apparatus according to any one of claims 1 to 5;
Processing the substrate to which the pattern is transferred in the step;
A device manufacturing method comprising: Forming a pattern on a resin on a substrate using the imprint apparatus according to claim 1;
A device manufacturing method comprising: