JPH0449527A - Method and device for exposure - Google Patents

Abstract

PURPOSE:To improve the intensity distribution of the exposure laser beam for head emission and to reduce the variance of power by detecting and correcting the positional deviation of an exposure laser beam emitted from a power control part. CONSTITUTION:This device consists of a rotative movement mechanism 2 where a photo resist disk 1 is stuck and is rotated and moved, a power control part 4 which controls the power of an exposure laser beam 3, a modulating part 5 which optically modulates the power controlled laser beam 3, a sensor part 7 which detects the extent of positional deviation of a laser beam 6 obtained by sampling the laser beam 3 through a sampler, a position correcting part 9 which corrects the extent of positional deviation of the exposure laser beam from the modulating part 5 by the extent of correction from a calculating part 8 which calculates the extent of correction in accordance with the extent of positional deviation from the sensor part 7, and a focus servo means 13. This means 13 condenses an exposure laser beam 10 from an expander 11, which expands the beam diameter of the beam 10 subjected to correction of positional deviation, and a focus beam 12 by an optical head 14 and detects the reflected light of the beam 12 from the disk 1 and outputs such actuator driving signal to the optical head 14 that the beam 12 is always focused on the disk 1.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an exposure method and apparatus.

[Conventional technology]

In the case of a conventional exposure method and apparatus for an optical disk master, as shown in FIG.
a rotational movement mechanism 2 that fixes, rotates, and moves; a power control section 4 that controls the power of the exposure laser beam 3; a modulation section 5 that optically modulates the power-controlled exposure laser beam 3; an expander 11 for expanding the beam diameter of the exposure laser beam 3 from the expander 11; an optical head 14 for condensing the exposure laser beam from the expander 11 and the focus laser beam 12; Detecting the reflected light of the focused laser beam 12 from the photoresist disk 1,
It comprises a focus servo means 13 that outputs an actuator drive signal d to the optical head 14 so that the focus servo beam 12 is always on the photoresist disk 1.

For example, an exposure laser beam is focused on the inner circumference of the photoresist disk 1 by a known focus servo means 13, the photoresist disk 1 is rotated by the rotational movement mechanism 2, and the photoresist disk 1 is rotated by the power control section 4. Spiral exposure can be performed by controlling the rotational movement mechanism 2 so that the power-controlled exposure beam exposes the photoresist disk 1 from the inner circumference to the outer circumference.

Therefore, by giving an ON signal to the modulation section 5,
Group exposure is performed, and the modulation section 5 is set to 0N-OFF'.
By applying a signal, bits can be exposed.

FIG. 3 is a block diagram showing an example of the power control section 4 shown in FIG. 2, and the exposure laser beam 3 is an analog A1
0 modulator 20. Analog A10 modulator 20
The emitted beam is sampled to have a beam power of about 5% by a beam sampler 21 to become a laser beam 23, and the rest is emitted as an exposure laser beam 22. The detector 24 detects the light intensity of the laser beam 23 and outputs it as a light intensity signal f. The light amount signal f becomes an input signal to the light amount correction section 25, and after being compared with the setting signal e applied to the terminal 100 and corrected, it is applied as the drive input signal g to the driver 26 of the analog A10 modulator 20. . Therefore, the analog A10 modulator 2 is controlled by the control signal output from the driver 26.
0 can control the exposure laser beam 3.

For example, in exposure at a constant rotation speed, the exposure laser power needs to increase from the inner circumference to the outer circumference of the photoresist disk 1, so the setting signal e of the power control unit 4 is It increases over time. At this time, the exposure laser beam 3 emitted from the analog A10 modulator 20 will shift in position if the setting signal e changes.

[Problem to be solved by the invention]

However, in the above-described conventional exposure method and apparatus, the power of the exposure laser beam is controlled by the power control section, so the settings of the driver of the analog A10 modulator are changed from the inner circumference to the outer circumference of the photoresist disk. Analog A10 when changing the signal
The exposure laser beam emitted from the modulator may be misaligned, and since the optical path of the exposure laser beam to the head exit is long, the exposure laser beam may be vignetted by optical elements along the way, causing the exposure laser beam to be distorted when the head exits. This has the drawback of deteriorating the intensity distribution and causing power fluctuations.

[Means to solve the problem]

The exposure method of the present invention detects the amount of positional deviation of the exposure laser beam, calculates a correction amount from the positional deviation amount, and corrects the positional deviation by correcting the optical axis of the exposure laser beam using this correction amount. It is configured as follows.

Further, the exposure apparatus of the present invention includes a laser beam power control section, a sensor section that detects the amount of positional deviation of the exposure laser beam emitted from the power control section, and an operation that calculates a correction amount from the amount of positional deviation. and a position correction section that corrects the positional deviation of the exposure laser beam using the correction amount.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

The exposure apparatus shown in FIG. 1 includes a rotational movement mechanism 2 that fixes and rotates a photoresist disk 1, and an exposure laser beam 3.
a power control section 4 for controlling power, a modulation section 5 for optically modulating the power-controlled exposure laser beam 3, and a positional shift amount of the laser beam 6 sampled from the power-controlled exposure laser beam through a sampler. a sensor unit 7 that detects the positional deviation of the sensor unit 7; a calculation unit 8 that calculates a correction amount from the positional deviation amount of the sensor unit 7; and a calculation unit 8 that corrects the positional deviation amount of the exposure laser beam of the modulation unit 5 from the correction amount of the calculation unit 8. an expander 11 that expands the beam diameter of the exposure laser beam 10 whose positional deviation has been corrected; an optical head 14 that focuses the exposure laser heated-focus beam 12 from the expander 11; The optical head 14 collects the light and detects the reflected light of the focus laser beam 12 from the photoresist disk 1, and controls the optical head 1 so that the focus of the focus laser beam 12 is always on the photoresist disk 1.
4 and 7. Focus servo means 13 outputs a motor drive signal d.

The sensor section 7 detects the amount of positional deviation of the exposure laser beam 6 sampled by the sampler, and outputs it to the calculation section 8 as a voltage signal a. As the configuration of the sensor section 7, for example, a positional deviation detection unit using a generally commercially available two-part sensor can be used.

The calculation unit 8 calculates data for correcting the detected positional deviation amount. For example, if the position correction section 9 and an XY-driven galvano mirror are used, the arithmetic section 8 outputs XYW positive data signals (s) and (c) for this galvano mirror.

The position detection unit 9 can correct the positional deviation of the laser beam by adjusting the exposure laser beam using, for example, an XY-driven galvanometer mirror.

〔Effect of the invention〕

The exposure method and apparatus of the present invention can detect and correct the positional deviation of the exposure laser beam emitted from the power control unit, thereby eliminating vignetting of the exposure laser beam by the optical element due to the positional deviation of the beam. This has the effect of improving the intensity distribution of the exposure laser beam emitted from the head and reducing power fluctuations.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is a block diagram showing an example of the conventional power control section, and FIG. 3 is a block diagram showing an example of the power control section shown in FIGS. 1 and 2. ■...Photoresist disk, 2...Rotation movement mechanism, 3...Exposure laser beam, 4...
...Power control section, 5...Modulation section, 6...
...Laser beam, 7...Sensor section, 8.
...Calculation section, 9...Position correction section, 10.
... Laser beam, 11 ... Expander, 12 ... Focus laser beam, 13.
... Focus servo means, 14 ... Optical head, 20 ... Analog A10 modulator, 21
...Sampling mirror 22.23...
...Laser beam, 24...Detector, 25...
...Light amount correction section, 26...Driver a...
...Voltage signal, b, c...Correction data signal, d...Actuator drive signal, e...
...Setting signal, f...Light level signal, g...
・Drive input signal, h...control signal, 100.
...Terminal. Agent Patent Attorney Susumu Uchihara L−+−−−−l−−−1−−”

Claims (2)

[Claims] (1) The positional deviation is corrected by detecting the amount of positional deviation of the exposure laser beam, calculating a correction amount from the positional deviation, and correcting the optical axis of the exposure laser beam using this correction amount. exposure method. (2) a laser beam power control unit, a sensor unit that detects the amount of positional deviation of the exposure laser beam emitted from the power control unit, a calculation unit that calculates a correction amount from the positional deviation amount, and the correction amount An exposure apparatus comprising: a position correction section that corrects a positional deviation of an exposure laser beam.