JPH05226212A - Method and apparatus for prevention of trouble of photolithographic technique - Google Patents

Abstract

PURPOSE:To prevent that a foreign body adheres to a reticle and that a defect such as a flaw or the like is caused. CONSTITUTION:A transfer pattern on a reticle 1 is read out by using a VTR apparatus 11 or a photographic apparatus; it is compared with a transfer pattern on a correct reticle; it is confirmed that no abnormality exists in the reticle immediately before its use; the transfer pattern is transferred. Thereby, it is possible to prevent the trouble of the reticle and the recycle of a wafer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly, to a method and a device for preventing troubles in an optical lithography technique for forming a transfer pattern on a semiconductor substrate.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a trouble prevention method of an optical lithography technique for drawing a transfer pattern on a semiconductor substrate is a dry plate for transfer (hereinafter referred to as a reticle).
After performing the particle inspection on 1, the transfer pattern is drawn. In the figure, 1 is a reticle, 7 is a laser particle inspection machine, and 8 is an ultraviolet light source (hereinafter abbreviated as UV light source). Reference numeral 9 is a resist-coated wafer, 10 is a stepper stage, and 12 is a transfer machine.

First, the reticle 1 is washed before being installed in the transfer machine 12, and then installed in the transfer machine 12. The particle inspection on the reticle 1 is performed in the transfer machine 12 by the laser particle inspection machine 7, and if abnormal particles are attached, the particles are cleaned again or replaced with another reticle.

Next, if the particle inspection on the reticle is passed, the reticle 1 is moved to the stepper stage 10 to transfer the transfer pattern U to the resist-coated wafer 9.
It was drawn by the V light source 8.

[0005]

By the way, in the above-mentioned conventional photolithography technique, the defect of the reticle 1 itself or the particle adhesion after the particle inspection cannot be found only by the particle inspection on the reticle 1, and the resist-coated wafer 9 is used. However, there is a drawback that a wrong transfer pattern is drawn, reproduction is performed, or manufacturing is performed unclear until the final product, resulting in a defective product.

[0006]

A method for preventing troubles of an optical lithography technique of the present invention automatically compares a recorded correct reticle image with a transfer pattern of a reticle,
The feature is that the transfer is performed after confirming that there is no abnormality.

When the transfer pattern of the reticle is composed of a plurality of identical individual patterns, one individual pattern is automatically compared with another individual pattern to confirm that there is no abnormality in the transferred pattern and then transfer. Is characterized by.

It is preferable to confirm whether or not there is an abnormality in the above pattern at the beginning of a series of transfers, and thereafter it can be performed at an appropriate frequency.

As an apparatus for implementing the above method, an apparatus for reading a transfer pattern on a reticle is compared with a read reticle and a correct reticle image recorded in advance, and it is automatically confirmed whether they are the same. And means.

Alternatively, an apparatus for reading a transfer pattern composed of a plurality of sets of the same individual pattern on the reticle and one individual pattern of the read pattern are compared with other individual patterns to determine whether they are the same. And a means for checking automatically.

[0011]

It is possible to surely find defects and particles on the reticle before drawing the transfer pattern.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a perspective view and a schematic view of an embodiment of the present invention. In the figure, 1 is a reticle, 2 is a foreign matter on the reticle, 8 is a reticle defect, 4 is a transfer pattern, 5 is a correct reticle image, 6 is a reticle immediately before use, 7 is a laser particle inspection machine, 8 is a UV light source, Reference numeral 9 is a resist-coated wafer, 10 is a stepper stage, 11 is the VTR device of the present invention, 12 is a transfer machine, and 13 is a display.

Next, the operation of the above optical lithography apparatus will be described. The reticle 1 is washed before being installed in the transfer machine 12, and then installed in the transfer machine 12. Next, the reticle 1 is moved onto the stepper stage 10, the particle inspection is performed by the laser particle inspection machine 7, and then the reticle 6 immediately before use is imaged by the VTR device 11, and the correct reticle image 5 previously recorded is obtained. The difference is automatically compared to determine whether there is an abnormality. If an abnormality is recognized, which part has an abnormality is displayed on the display 13.

If there is no abnormality, the transfer pattern 4 is drawn on the resist-coated wafer 9 by the UV light source 8 as usual.

According to this embodiment, it is possible to instantly observe on the display 13 where the foreign matter 2 and the defect 3 on the transfer pattern on the reticle 1 are present. Therefore, the wrong transfer pattern 4 is a resist-coated wafer. 9 has an advantage that drawing is not performed.

Further, the work can be guaranteed by performing the reticle inspection again after the transfer is completed. In addition, even if there is an abnormality, there is an advantage that troubles can be detected early.

In the above embodiment, the reticle inspection is performed only in the first step and the last step of the transfer to the wafer, but it may be performed in the middle or each step.

[0018]

Second Embodiment The second embodiment is the same as the first embodiment except that the VTR device 11 is replaced with a photographic device.
Illustrations, descriptions and advantages are omitted.

[0019]

[Third Embodiment] FIG. 2 is a perspective view of a third embodiment of the present invention. This embodiment is different in that the reticle 6 just before use is used instead of the correct reticle image 5 of the first embodiment. This usually means that the transfer pattern 4 on one reticle 1 has two to four identical individual patterns. An abnormal pattern is found on the basis of this one individual pattern.
Since the second embodiment is the same as the first embodiment except for the above points, description and advantages are omitted.

[0020]

As described above, according to the present invention, the use of the VTR device 11 or the photographic device in the photolithography technique has the effect of completely preventing defects and particle adhesion in the transfer pattern of the reticle. .

Further, there is no need to regenerate a wafer due to a reticle trouble, which has been conventionally performed, and product defects can be eliminated, so that a large number of troubles can be prevented.

[Brief description of drawings]

FIG. 1 is a perspective view of a reticle according to a first embodiment of the present invention and a schematic view of an optical lithography technique using a VTR device (or a photographic device).

FIG. 2 is a perspective view of a reticle used in a third embodiment of the present invention.

FIG. 3 is a schematic view of a conventional optical lithography technique.

[Explanation of symbols]

 1 reticle (dry plate for transfer) 2 foreign matter on reticle 3 reticle defect 4 transfer pattern 5 initial reticle image 6 reticle just before use 7 laser particle inspection machine 8 UV light source 9 resist-coated wafer 10 stepper stage 11 of the present invention VTR device (photographic device) 12 Display

Claims (5)

[Claims] 1. A method for preventing a trouble in an optical lithography technique, which comprises automatically comparing a transfer pattern of a reticle installed on a stepper with a correct reticle image recorded in advance and confirming that there is no abnormality before transferring. . 2. A transfer pattern is abnormal by automatically comparing one individual pattern with another individual pattern in a state where a reticle having a transfer pattern composed of a plurality of identical individual patterns is installed on a stepper. A method for preventing troubles in optical lithography technology, which comprises performing transfer after confirming that there are no defects. 3. The method for preventing troubles in the optical lithography technique according to claim 1, wherein the presence or absence of abnormality in the transfer pattern is confirmed at the beginning of a series of transfers. 4. A device for reading a transfer pattern on a reticle installed on a stepper, and means for comparing the read pattern with a prerecorded correct reticle image and automatically confirming whether they are the same or not. A stepper device characterized in that 5. A device for reading the transfer pattern in the state where a reticle having a transfer pattern composed of a group of a plurality of identical individual patterns is installed on a stepper, and one individual pattern of the read pattern and another individual pattern are compared. And a means for automatically confirming whether they are the same or not.