JPS6161671B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser repair device. Further, the present invention can be applied to, for example, a semiconductor integrated circuit chip (hereinafter referred to as
It is written as IC chip. ) relates to a laser repair device that has the ability to connect disconnected portions of wiring above.

As shown in Figure 1, the laser repair device includes a laser device, an optical system, a laser control system, and
It consists of a table mechanism section, and its purpose is, for example, an IC
This is the removal of residual defects that exist in photomasks, etc. In FIG. 1, 1 is an optical system of an optical microscope, 2 is a filter, and 3 is an objective lens. 4 is a sample to be irradiated with laser. 5 is a pilot light source for monitoring the spread of the laser beam, and 6 is a slit for controlling the shape of the laser beam. The laser light emitted from the laser device 7 passes through a beam expander 9 and is finally irradiated onto the sample along the optical path shown in the figure. In the figure, 8 is a laser control system, and 10 is a table mechanism that enables movement of the sample in X, Y, and θ. The shape and width of the laser beam can be changed arbitrarily by the slit 6. Currently, it is possible to narrow the beam down to a square beam with a side of 2 μm, and the shape can be arbitrarily selected from rectangular to circular.

FIG. 2 is an explanatory diagram of the case where residual pattern defects on a glass mask are repaired using such a laser repair device. The pattern on the glass mask is generally formed of a thin film of metal such as chromium. In FIG. 2a, 11 is a wiring pattern made of a thin chromium film on a glass mask. Now, if there is a pattern defect like the one shown at 12 in the figure, adjust a rectangular slit image like the one shown at 13 in Figure 2b to this part so that it overlaps with the remaining defect while looking at the microscope. Thereafter, when a laser beam is irradiated, a chromium thin film is instantaneously deposited by the laser, and the remaining defects are removed as shown at 14 in FIG. 2c.

As explained above, conventional laser repair equipment can remove pattern defects such as residual defects, but cannot repair missing defects such as disconnections in the wiring pattern on a glass mask, for example.

If both residual defects and missing defects can be corrected using the same device, any defect can be corrected, and the effect is very large.

The present invention relates to a laser repair device capable of repairing both residual defects and missing defects,
A description will be given below based on specific examples.

FIG. 3 shows a principle diagram of laser repair according to the present invention. In the figure, 15 is a laser beam, 16 is a transparent long film, and a conductive thin film 17 is formed on one side of the film. 18 is a sample.
Now, when a laser beam is irradiated from above the transparent long film, a part of the conductive thin film 17 irradiated with the laser instantaneously evaporates and adheres to the surface of the sample 18. Figure 3a shows the direction of the evaporated material of the conductive thin film when irradiated with a laser beam, and Figure 3b shows a part 19 of the conductive thin film deposited on the sample surface after laser irradiation. It is a diagram.

The area and shape of the conductive thin film reattached to the sample surface largely depend on the distance d between the long film and the sample.

FIG. 4 is an explanatory diagram showing how the area of the conductive thin film reattached to the sample surface changes depending on the difference in the distance d between the long film and the sample.
The contents of the numbers in the figure correspond to the contents of the numbers in FIG. In Fig. 4 a, the spacing is d ₁ , and in Fig. 4 b, the spacing is d ₂
and d ₁ > d ₂ . At this time, if the widths of the laser beams are w ₁ and w ₂ , respectively, the widths of the conductive film re-deposited on the sample surface are w ₁ ′ and w ₂ ′. Now w ₁
= w ₂ , then (w ₁ ′/w ₁ )>(w ₂ ′/w ₂ ), so in order to redeposit a conductive film with a width almost equal to the width of the laser beam onto the sample surface, d must be Smaller is preferable. For example, the width of the laser beam is 10~20
In the case of about .mu.m, the value of d is suitably 10 to 20 .mu.m or less.

FIG. 5 is an explanatory diagram showing the principle of laser repair according to the present invention in an easy-to-understand manner. A conductive film as shown in 19 is deposited on the surface of the sample by laser beam irradiation. When the laser beam is rectangular, the shape of the conductive film deposited on the sample is a rectangle with slightly rounded corners.

FIG. 6a shows a disconnection in a wiring section on the surface of an IC chip, glass mask, or liquid crystal display device. When a conductive film 21 having a shape as shown in FIG. 6b is deposited on this wiring 21 according to the principle of the present invention, the disconnected portion of the wiring is connected as shown at 22 in FIG. 6c. .

The material of the long film used in the present invention is:
Any transparent film may be used as long as it absorbs little laser beam. For example, a plastic film with a transmittance of 80% or more may be used, or an inorganic transparent plate such as a glass plate or a quartz plate may be used. The conductive thin film on the transparent long film may be a metal thin film such as gold, nichrome or aluminum, a semiconductor conductive film such as a polysilicon thin film, or a transparent conductive film such as tin oxide or indium oxide. A thin film may also be used. These can be easily formed on a transparent long film by vapor deposition or sputtering.

FIG. 7 is an external view of a transparent long film 23 having a conductive thin film 24 on one side. In this embodiment, the conductive thin film is formed to have the same width as the long film.

FIG. 8 shows another embodiment of the long film of the present invention. In this embodiment, the width w _B of the conductive thin film 26 is smaller than the width w _A of the long film 25 .

For example, as mentioned above, in order to connect a broken wire with a width of 10 to 20 μm, if a conductive thin film with a width of 10 to 20 μm is formed on a transparent long film in advance, alignment can be made easily. It's convenient. In this case, it is preferable to set the width of the long film to about 1 mm to 10 mm in order to obtain film strength.

FIG. 9 is an explanatory diagram of this long tape actually inserted between the objective lens 27 of the microscope and the sample 31. 28 is a laser beam. The distance S between the objective lens and the sample changes depending on the magnification of the lens. Therefore, it is desirable to have a mechanism that allows the position of the long film to be moved up and down within this range of S. In the figure, 29 is a transparent long film, and 30 is a conductive thin film.

FIG. 10 is a diagram of a mechanism for moving a long film in a laser repair apparatus according to the present invention. A long film having a conductive thin film deposited on one side is wound onto a reel 32 from a reel 33. That is, the used tape is moved little by little by the reel feeding mechanism.

FIG. 11 shows another embodiment of the laser repair apparatus according to the present invention. As explained earlier, in order to deposit a conductive thin film having a shape close to that of the laser beam, the distance between the long film and the sample should be narrow. If possible, it is better to have contact with each other to the extent that they do not cause any damage. This embodiment relates to a mechanism in which a long film and a sample come into slight contact. 35 in the figure is a nozzle through which the gas 34 flows. The gas is sprayed through a nozzle onto the area to be irradiated with the laser beam as shown in the figure. The gas may be nitrogen gas or air. FIG. 11a shows the state before gas is sprayed. When the gas is blown, the long film is pushed downward and makes slight contact with the sample surface. This state is shown in FIG. 11b. If you irradiate a laser beam in this state,
A conductive thin film with a shape close to that of the laser beam will be re-deposited onto the sample.

FIG. 12 shows an example of a repair method using the laser repair device of the present invention. When it is desired to connect a broken line in the wiring as shown at 36 in the figure, the conductive thin film pattern 38 on the long film 37 is aligned with the broken line as shown in the figure, and the area surrounded by 39 in the figure is connected. Just irradiate it with a laser beam.

As described above with reference to many embodiments, the present invention relates to a pattern repair method using a laser, and particularly relates to a laser repair device that can repair defects (such as wire breaks) in IC chips. It is very promising for connecting disconnections in glass masks and connecting disconnections in Nesa patterns on liquid crystal panels. In the description of the present invention, the re-deposition of a conductive thin film was mainly explained, but it is clear that the present invention is also applicable to the case of an insulating thin film.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional laser repair device.
Figures 2a, b, and c are diagrams illustrating the repair of residual defects by a conventional laser repair device, and Figures 3a,
b, FIGS. 4a and 4b, FIG. 5, and FIGS. 6a, b, and c are diagrams illustrating a method of repairing a defect using the laser repair device according to the present invention. Figures 7a, b and 8
Figures a and b are diagrams illustrating a long film used in the laser repair device of the present invention. 9 to 11a and 11b are diagrams explaining the mechanism of the laser repair device according to the present invention. FIG. 12 is a diagram showing an example of repair using the laser repair device according to the present invention. 1... Microscope, 2... Filter, 3... Objective lens, 4... Sample, 5... Pilot light source, 6...
...Slit, 7...Laser device, 8...Laser control system, 9...Beam expander, 10...
Table control system, 11... Wiring pattern, 12...
...Residual defects, 13...Shape of laser beam, 1
4... Residual defect after correction, 15... Laser beam, 16... Transparent long tape, 17... Conductive thin film, 18... Sample, 19... Redeposited conductive thin film, 20... Broken wire A certain wiring pattern, 21...
Shape of laser beam, 22... Modified wiring pattern, 23... Long film, 24... Conductive thin film, 25... Long film, 26... Conductive thin film, 27... Objective lens, 28... Laser Beam, 29... Long film, 30... Conductive thin film,
31... Sample, 32... Reel, 33... Reel, 34... Gas, 35... Nozzle, 36... Wiring pattern with disconnection, 37... Long film,
38... Conductive thin film, 39... Laser beam shape.

Claims (1)

[Claims] 1. Laser repair that includes a laser device, an optical system, a laser control system, and a table mechanism, and irradiates a laser beam onto the surface of a sample on a table by limiting the laser irradiation range while observing with a microscope. 1. A laser repair device, characterized in that the device has a mechanical part in which a transparent film having a conductive thin film formed on one side moves between an objective lens of the microscope and the surface of the sample. 2. The laser repair device according to claim 1, wherein the transparent film is a long film. 3. The laser repair device according to claim 1, wherein the transparent film is a plastic film having a transmittance of 80% or more. 4. The laser repair device according to claim 1, wherein the transparent film is a thin and elongated plate of glass or quartz. 5. The laser repair device according to claim 1, wherein the conductive thin film is a metal thin film. 6. The laser repair device according to claim 1, wherein the conductive thin film is a transparent conductive thin film. 7. The laser repair device according to claim 2, wherein the conductive thin film on the transparent long film has an elongated stripe shape, and the width thereof is smaller than the width of the long film. 8. The laser repair device according to claim 1, further comprising a mechanism that can arbitrarily set the distance between the transparent film and the sample surface. 9. The laser repair device according to claim 2, further comprising a mechanism for winding the long film from reel to reel. 10 A laser repair device that has a laser device, an optical system, a laser control system, and a table mechanism, and irradiates a laser beam onto the surface of a sample on a table by limiting the laser irradiation range while observing it with a microscope. A mechanism part in which a transparent film on which a transparent thin film is formed moves between the objective lens of the microscope and the sample surface, and a gas from a nozzle is blown onto the transparent film during laser irradiation to create a transparent film. A laser repair device characterized by having a mechanical part where a film and a surface of a sample to be irradiated with a laser come into contact.