Method of repairing substrate

A method of repairing a substrate that may prevent a metal layer from being corroded. A substrate including a metal layer and an insulating layer on the metal layer is first provided. Then, a laser beam having a wavelength range having a high transmittance with respect to the insulating layer is irradiated to selectively remove a portion of the metal layer. Also, a first laser beam is irradiated to remove a portion of the metal layer and a portion of the insulating layer, and then a second laser beam is irradiated onto side surfaces of the exposed insulating layer to melt the insulating layer, thereby forming a corrosion preventing layer covering the metal layer.

CLAIM PRIORITY

This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application earlier filed in the Korean Intellectual Property Office on 3 Jan. 2013 and there duly assigned Ser. No. 10-2013-0000705.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a method of repairing a substrate.

2. Description of the Related Art

The present disclosure herein relates to a method of repairing a substrate, and more particularly, to a method of repairing a substrate using laser beam.

SUMMARY OF THE INVENTION

The present disclosure provides methods of repairing a substrate that may selectively remove a portion of a short-circuited metal layer without having an influence on another layer.

The present disclosure also provides methods of repairing a substrate that may prevent corrosion of a metal layer exposed after a short-circuited portion between metal layers and an insulating layer are removed.

Embodiments of the inventive concept provide methods of repairing a substrate including: providing a substrate including a metal layer and an insulating layer on the metal layer; and irradiating a laser beam of a first wavelength range in a perpendicular to the substrate to selectively remove a portion of the metal layer.

In some embodiments, the laser beam may be irradiated until the temperature of the metal layer arrives at least at a melting point of the metal layer.

In other embodiments, the laser beam may be irradiated using a wavelength variable solid laser.

In still other embodiments, the insulating layer may be made of a silicon-based material, for example, silicon oxide. In even other embodiments, the first wavelength range is about 2-6 μm.

In other embodiments of the inventive concepts, methods of repairing a substrate include: providing a substrate including a metal layer and an insulating layer on the metal layer; irradiating a first laser beam in a perpendicular to the substrate to selectively remove a portion of the metal layer and a portion of the insulating layer; and irradiating a second laser beam onto a side surface of the insulating layer to form a corrosion preventing layer covering the side surface of the insulating layer.

In some embodiments, the metal layer may be made of a metal having a melting point higher than the insulating layer.

In other embodiments, the second laser beam may be irradiated until at least the temperature of the insulating layer arrives at the melting point of the insulating layer and before at least the temperature of the metal layer arrives at the melting point of the metal layer.

In still other embodiments, the second laser beam may be irradiated with a predetermined slope with respect to a direction perpendicular to the substrate. In even other embodiments, the second laser beam may be irradiated to form a closed loop on a plane along the side surface of the insulating layer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers, patterns and/or sections, these elements, components, regions, layers, patterns and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer pattern or section from another region, layer, pattern or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.

Generally, in forming displays and semiconductors, a metal layer is formed on a substrate and then an insulating layer is formed thereon. At this time, the metal layer may be used variously for a metal wiring, a metal pattern, etc.

In spite that the metal layer should be formed in plurality on the same layer and the plurality of metal layers should be electrically isolated according to circumstances, the plurality of metal layers may be short-circuited due to a process error.

To solve the above-mentioned problem, a method in which a laser beam is irradiated onto the substrate formed with the metal layer and the insulating layer to remove some of the short-circuited metal layer is used.

However, the existing method does not selectively remove only some of the short-circuited metal layer but also removes some of the insulating layer thereon together with the some of the metal layer. As a result, the metal layer may be unnecessarily exposed through the removed insulating layer and thus the exposed metal layer may be corroded.

FIG. 1is a flow diagram illustrating a substrate repairing method according to an embodiment of the inventive concept, andFIGS. 2 and 3are cross-sectional views illustrating the substrate repairing method ofFIG. 1.

Referring toFIGS. 1 and 2, in operation51, a substrate100is first provided. The substrate100includes an insulating substrate10, a metal layer20, and an insulating layer30.

The substrate100may include a first region, a second region and a third region. The second region may be disposed between the first region and the third region.

The metal layer20may be disposed on the insulating substrate10. The metal layer20may include a first metal layer21, a second metal layer22, and a third metal layer23. The first metal layer21may be a portion of the metal layer20corresponding to the first region, the second metal layer22may be a portion of the metal layer20corresponding to the second region, and the third metal layer23may be a portion of the metal layer20corresponding to the third region.

The first metal layer21and the third metal layer23may be short-circuited by the second metal layer22.

The metal layer20may be used variously for a metal wiring, a metal pattern, etc. In an example, in the case where the metal layer20is a metal wiring, the first metal layer21and the third metal layer23are wirings to which different signals are applied, and the second metal layer21may be formed due to various reasons such as a process error, etc. to short-circuit the first metal layer21and the third metal layer23. That is, the second metal layer21may be a configuration which should be removed so as to electrically and physically separate the first metal layer21and the third metal layer23from each other.

The insulating layer30may be formed on the metal layer20to cover the metal layer20, thus isolating the metal layer20from an outside.

The insulating layer30may be a silicon-based material, for example, silicon oxide (SiOx), silicon nitride (SiNx), or the like. The silicon-based material is transparent and has a high insulation property so as to insulate the metal layer20from an outside.

Transmittance of light incident into silicon (Si) may be different according to the wavelengths. When the wavelength of light incident into silicon is about 4 μm, the incident light exhibits the highest transmittance. The silicon-based material contains silicon atoms as a main component and has a similar light transmittance characteristic to silicon. For example, when the wavelength of the incident light is about 2-6 μm, the silicon-based material has the highest light transmittance characteristic.

Although not illustrated in the drawings, at least one layer may be disposed between the insulating substrate10and the metal layer20.

In operation S2, laser beam (LZ) is irradiated onto the substrate100in a direction (D1) perpendicular to the substrate100to selectively remove a portion of the metal layer20.

At this time, the laser beam (LZ) may be irradiated by using a wavelength variable solid laser. Therefore, the wavelength of the laser beam (LZ) may be set to a range of about 2-6 μm that has a high transmittance with respect to the insulating layer30.

The laser beam (LZ) may be irradiated onto the second region. The laser beam (LZ) passes through the insulating layer30in the second region and transfers energy to the second metal layer22.

Since the second metal layer22has an inherent melting point, when the second metal layer22may be heated to a temperature of not less than the melting point thereof, the second metal layer22starts to be melted.

Since the temperature of the second metal layer22increases in proportion to the irradiation time of the laser beam (LZ), the laser beam (LZ) may be irradiated until the temperature of the second metal layer22arrives at the melting point of the metal layer20. By maintaining the temperature of the second metal layer22at a temperature of not less than the melting point of the metal layer20through the irradiation of the laser beam (LZ) for a predetermined time, the second metal layer22may be selectively removed.

Referring toFIG. 3, it may be confirmed that the second metal layer22was removed by the laser beam (LZ).

According to the substrate repairing method in an embodiment of the inventive concept, only the second metal layer22may be selectively removed to electrically and physically separate the first metal layer21and the third metal layer23from each other. Since the insulating layer30is not changed, it continues to perform a role to insulate the first metal layer21and the third metal layer23from an outside. Also, since a side surface21aof the first metal layer21and a side surface23aof the third metal layer23which are exposed by the removed second metal layer22are isolated from an outside by the insulating layer30, they are not corroded due to moisture.

FIG. 4is a flow diagram illustrating a substrate repairing method according to another embodiment of the inventive concept,FIGS. 5, 6A and 7are cross-sectional views illustrating the substrate repairing method ofFIG. 4, andFIG. 6Bis a plan view an irradiation path of a second laser beam.

Referring toFIGS. 4 and 5, in operation S11, a substrate200is first provided. Since the substrate200is substantially the same as the substrate100in the previous embodiment described with reference toFIGS. 2 and 3except for the material constituting a metal layer40, like reference numerals are assigned to the remaining elements except for the metal layer40, and detailed description thereof will be omitted.

The metal layer40may include a first metal layer41, a second metal layer42, and a third metal layer43. The first metal layer41may be a portion of the metal layer40corresponding to the first region, the second metal layer42may be a portion of the metal layer40corresponding to the second region, and the third metal layer43may be a portion of the metal layer40corresponding to the third region.

The first metal layer41and the third metal layer43may be short-circuited by the second metal layer42.

The metal layer40may be used variously for a metal wiring, a metal pattern, etc. In an example, in the case where the metal layer40is a metal wiring, the first metal layer41and the third metal layer43are wirings to which different signals are applied, and the second metal layer42may be formed due to various reasons such as a process error, etc. to short-circuit the first metal layer41and the third metal layer43. That is, the second metal layer42may be a configuration which should be removed so as to electrically and physically separate the first metal layer41and the third metal layer43from each other.

The metal layer40may be formed of a metal having a higher melting point than the insulating layer30, for example, chromium (Cr).

Also, the metal layer40may be formed in a plurality of layers. When the metal layer40is formed in a plurality of layers, the layer, among the plurality of metal layers, contacting the insulating layer30may be made of a metal having a higher melting point than the insulating layer30.

Thereafter, a first laser beam (LZ1) may be irradiated onto the substrate200in a direction perpendicular to the substrate200to selectively remove some of the metal layer40and some of the insulating layer30.

At this time, the first laser beam (LZ1) may be irradiated to the second region. The first laser beam (LZ1) transfers energy to some of the insulating layer30and some of the metal layer40which are on a traveling path thereof.

Referring toFIG. 6A, some of the insulating layer30and the second metal layer42corresponding to the second region are removed by the first laser beam (LZ1), so that a side surface30aof the insulating layer30, a side surface41aof the first metal layer41and a side surface43aof the third metal layer43are exposed.

Thereafter, in operation S13, a second laser beam (LZ2) may be irradiated onto the side surface30aof the insulating layer30to melt the side surface30aof the insulating layer30.

The second laser beam (LZ2) may be irradiated with a direction (D2) inclined by a predetermined angle with respect to a direction (D1) perpendicular to the substrate200. This operation may be performed to precisely irradiate the second laser beam (LZ2) onto the side surface30aof the insulating layer30and to increase the irradiation area of the second laser beam (LZ2).

Referring toFIG. 6B, the second laser beam (LZ2) may be irradiated so as to form a closed loop along the side surface30aof the insulating layer30in the inclined direction (D2) on a plane. The dotted line ofFIG. 6Bmay be an irradiation path of the second laser beam (LZ2). By doing so, the second laser beam (LZ2) may be irradiated to all the side surfaces30aof the insulating layer30. In the case where the insulating layer30and the second metal layer42are removed in a circular form on a plane by the first laser beam (LZ1) as illustrated inFIG. 6B, the second laser beam (LZ2) may be irradiated in a circular form along the side surface30aof the insulating layer30.

The second laser beam (LZ2) may be irradiated until at least the temperature of the side surface30aof the insulating layer30arrives at the melting point of the insulating layer30and before at least the temperatures of the side surface41aof the first metal layer41and the side surface43aof the third metal layer43arrive at the melting point of the metal layer40.

Since the temperature rise of a material by irradiation of the second laser beam (LZ2) may be determined by variables, such as the wavelength and the irradiation time of the second laser beam (LZ2), the insulating layer30may be selectively melted by controlling these variables.

The first laser beam (LZ1) and the second laser beam (LZ2) may be irradiated by using a wavelength variable solid laser. The first laser beam (LZ1) and the second laser beam (LZ2) are irradiated in a condition that at least one of wavelength and irradiation time may be different from each other. This is because the first laser beam (LZ1) should melt both of the insulating layer30and the metal layer40, and the second laser beam (LZ1) should selectively melt only the insulating layer30as described above.

Referring toFIG. 7, in operation S14, a corrosion preventing layer50covering the exposed side surface41aof the first metal layer21and the exposed side surface43aof the third metal layer43may be formed by using the side surface30aof the insulating layer30remaining after the melting.

Some of the insulating layer30remaining after the melting may be melted by the second laser beam (LZ2) to fill a space between the side surface41aof the first metal layer41and the side surface43aof the third metal layer43, thereby forming the corrosion preventing layer50. Since the corrosion preventing layer50may be formed by melting the insulating layer30, the corrosion preventing layer50may be made of the same material as the insulating layer30.

The corrosion preventing layer50covers at least the side surface41aof the first metal layer41and the side surface43aof the third metal layer43. InFIG. 7, it is exemplarily illustrated that the corrosion preventing layer50covers the side surface41aof the first metal layer41, the side surface43aof the third metal layer43, and a top surface of the insulating substrate10. However, the inventive concept is not limited thereto. For example, if the corrosion preventing layer50may cover the side surface41aof the first metal layer41and the side surface43aof the third metal layer43by controlling the melting amount of the insulating layer30, the top surface of the insulating substrate10may be partially exposed.

According to the substrate repairing method in another embodiment of the inventive concept, by forming the corrosion preventing layer50, the side surfaces of the first metal layer41and the third metal layer43which are exposed in the course of electrically and physically separating the first metal layer41and the third metal layer43may be insulated from an outside. Therefore, the side surfaces of the first metal layer41and the third metal layer43are not corroded due to moisture.

As described above, according to the substrate repairing method in an embodiment of the inventive concept, some of a short-circuited metal layer may be selectively removed without causing a variation in an insulating layer by irradiating a laser beam.

According to the substrate repairing method in another embodiment of the inventive concept, after a short-circuited metal layer and an insulating layer are removed, the insulating layer may be selectively melted to form a corrosion preventing layer covering the exposed metal layer, thereby preventing corrosion of the metal layer.