JPH06326465A - Manufacture of multilayer board - Google Patents

Abstract

PURPOSE:To provide a method of manufacturing a board of high reliability, wherein an insulating layer can be flattened by removing its projections and the board can be easily enhanced in number of layers. CONSTITUTION:A conductor pattern 4 is formed on a board 6, an insulating layer 5 is formed on the conductor pattern 4, a mask is provided to the end face of the board 4 protruding to cut off laser ray 3, laser ray is made to irradiate in parallel with the board 6, and the part of the insulating layer 5 protruding above the mask 7 is removed by laser ray 3 transmitted through the mask 7. Or, a groove sloped by a prescribed angle is provided to the one side of the board, an end dummy pattern is formed on the part of the board which confronts the slope of the groove protruding above a conductor pattern to shade laser ray, a slope dummy pattern is formed on the slope of the groove protruding above the end dummy pattern to reflect laser ray. Laser ray is made to irradiate the slope dummy pattern to obtain the reflected laser ray parallel with the board, and an insulating layer protruding above the end dummy pattern is removed by the reflected laser ray concerned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board on which a semiconductor device or the like is mounted, and more particularly to a method for manufacturing a multilayer board.

[0002]

2. Description of the Related Art Generally, when manufacturing a multi-layer substrate, a conductor pattern such as copper is formed on the substrate, an insulator such as polyimide is coated on the substrate, and a through hole is formed by laser or other etching method. Repeatedly build up a multi-layer structure of several layers to several tens of layers. For example, Fig. 9 is a publication ("Electronic Materials" 5, p54 (1990))
9A to 9C are cross-sectional views showing a method of manufacturing the conventional multilayer substrate shown in FIG. 1 in order of steps, wherein FIG. 9A is a step A, that is, a substrate dicing step, and FIG. 9B is a step B, that is, a first-layer conductor pattern forming step. 9C is a step E, that is, a step of forming a first insulating layer, and FIG. 9D is a step G, that is, a step of forming a conductive hole and an insulator removing step on a dicing line.
9E is a step H, that is, a step of forming a second-layer conductor pattern, FIG. 9F is a step I, that is, a multilayer substrate formed by repeating the above process, and FIG. It is sectional drawing which shows each of the cut | disconnected multilayer substrate. In the figure, 3 is a laser for opening a conduction hole, 4 is a conductor such as copper, 5 is an insulating layer such as polyimide, 6 is a substrate such as silicon, and 7 is a mask that blocks the laser.

Since a multi-layer substrate formed by such a process can form many circuits in a small area, it enables high-density mounting and is suitable for downsizing and speeding up of electronic devices. It is being advanced.

[0004]

Since the conventional multilayer substrate is manufactured as described above, the convex portions of the conductor pattern 4 in the lower layer affect the upper layer as the layers are made into multiple layers, and these are accumulated. There are problems that the shape of the conductor pattern 4 is broken and the reliability is lowered, or the conductor pattern 4 cannot be formed.

The present invention has been made in order to solve the above-mentioned problems, and the projections of the insulating layer 5 can be removed, and the flattening can be performed, so that a multilayer can be easily formed and a highly reliable substrate can be obtained. It is an object of the present invention to provide a manufacturing method capable of obtaining

[0006]

According to a first aspect of the present invention, there is provided a method of manufacturing a multi-layer substrate, including a step of forming a conductor pattern on the substrate, a step of forming an insulating layer on the conductor pattern, and an end portion of the substrate. A mask that projects from the conductor pattern and blocks the laser light is arranged, and the step of removing the insulating layer protruding from the mask by irradiating the substrate with the laser light in parallel and passing through the mask is performed. is there.

According to a second aspect of the present invention, there is provided a method of manufacturing a multi-layer substrate, wherein at least one surface of the substrate is provided with a groove inclined at a predetermined angle, a step of forming a conductor pattern on the substrate, and an inclined portion of the groove. A step of forming an end dummy pattern projecting from the conductor pattern on the opposing substrate and blocking laser light, a step of forming an inclined dummy pattern projecting from the end dummy pattern and reflecting a laser beam on the inclined part of the groove, A step of forming an insulating layer on the conductor pattern and irradiating the inclined part dummy pattern with a laser beam to obtain a reflected laser beam parallel to the substrate, and the reflected laser beam projects from the end dummy pattern. The step of removing the insulating layer is performed.

Further, in the method for manufacturing a multilayer substrate according to the invention of claim 3, the step of forming a conductor pattern on the substrate, the step of forming a dummy pattern protruding from the conductor pattern and blocking laser light on the substrate, the conductor pattern The step of forming an insulating layer on the above and irradiating a laser beam to a mirror inserted at a tilt in the vicinity of the dummy pattern to obtain a reflected laser beam parallel to the substrate, and this reflected laser beam causes the reflected laser beam to project from the dummy pattern. The step of removing the existing insulating layer is performed.

[0009]

According to the method of manufacturing a multilayer substrate in the first aspect of the invention, a part of the laser light radiated parallel to the substrate from the side surface of the substrate is shielded by the mask, and the insulating layer is projected by the laser light passing through the mask. The portions are removed, and only the extremely thin insulating film on the conductor pattern remains uniformly, so that planarization is achieved.

According to the method of manufacturing a multilayer substrate in the second aspect of the invention, the insulating layer is removed by the laser beam parallel to the substrate reflected by the inclined dummy pattern. At this time, since the excess laser light is blocked by the end dummy pattern, only the extremely thin insulating layer on the conductor pattern remains uniformly, so that flattening is achieved with high accuracy.

Further, according to the method of manufacturing a multilayer substrate in the third aspect of the invention, the insulating layer is removed by the laser light parallel to the substrate reflected by the mirror. At this time, since the extra laser beam is blocked by the dummy pattern, only the extremely thin insulating layer on the conductor pattern remains uniformly, so that the planarization is achieved with high accuracy.

[0012]

EXAMPLES Example 1. An embodiment of the invention of claim 1 will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the main part of the method for manufacturing a multilayer substrate according to the first embodiment.
Is a laser beam applied parallel to the substrate 6 from the side surface of the substrate 6, 4 is a conductor pattern formed on the substrate 6, 5 is an insulator formed on the conductor pattern, and 7 is a conductor pattern 4 on the end of the substrate 6. It is a mask that is arranged so as to project further and shields unnecessary laser light.

In the present invention, the irradiated laser beam 3
Is partially shielded by the mask 7 and the desired conductor pattern 4
Only the extremely thin insulating layer 5 above is left evenly, and the excess insulating layer protruding from the mask 7 is removed, so that planarization is achieved.

Example 2. Further, in the present invention, the mask 7 may be in close contact with the substrate 6 or may be separated therefrom.
For example, the case type shown in FIG. 2 may be used.

Example 3. Further, a dummy pattern may be formed as shown by 2 in FIG. 3 and this may be used as a mask. This dummy pattern 2 can also be used as a conductive path to the next layer. After this, the dummy pattern 2
May be removed, or may be left if there is no particular problem.

The laser beam irradiation may be mask transfer or positioning spot irradiation. Irradiation whose direction is adjusted using a mirror may also be used.

The mask 7 and the dummy pattern 2 are not particularly limited as long as they are materials that shield the laser light 3, but for example, metals such as copper, gold, silver and aluminum that reflect the laser light 3 are preferable. For example, conductor pattern 4
When plated copper is used for the above, it may be formed of the same material at the same time. In addition, in order to remove it, a ceramic such as alumina, which requires a higher energy density than the insulating layer 5, is used.
Irradiation may be performed at an energy density that can remove the insulating layer 5 but does not remove alumina. The mask and the dummy pattern may be removed at the same time, and if the thickness can be controlled, the same material as the insulating layer 5 may be used, or another organic material may be used.

The insulating layer 5 may be made of any material as long as it has good insulating properties and can be easily treated such as coating, but generally a polymer material such as polyimide or epoxy resin is used.

Further, the laser light 3 is not particularly limited, but an excimer laser having a low heat damage and capable of high quality removal, a short wavelength laser such as a YAG harmonic, or a short pulse laser is preferable. For example, when using a KrF excimer laser,
Dozens of meters to remove the insulating layer 5 made of polyimide
Energy of J / cm ² to several tens of J / cm ² may be used.

Example 4. Next, an embodiment of the invention of claim 2 will be described with reference to the drawings. 4A to 4C are cross-sectional views showing a method of manufacturing a multilayer substrate according to a fourth embodiment in the order of steps. In FIG. 4, 1 is a dummy pattern of an inclined portion formed in an inclined portion of a groove, and 2 is a substrate facing the inclined portion of the groove. On conductor pattern 4
The end portion dummy pattern 1 is formed so as to protrude further, and the inclined portion dummy pattern 1 is formed so as to protrude from the end portion dummy pattern 2. 4A is a sectional view showing a step A, that is, a dicing step in which the substrate 6 is diced to form a V-shaped groove, and FIG. 4B is a sectional view showing a step B, that is, a step of forming the conductor pattern 4 of the first layer. FIG. 4C is a sectional view showing the step C, that is, the step of forming the dummy patterns 1 and 2, and FIG. 4D is the step D, that is, the thickness of the inclined dummy pattern 1 so as to protrude from the end dummy pattern 2. 4E is a sectional view showing a step of forming a film, FIG. 4E is a sectional view showing a step E, that is, a step of forming the first insulating layer 5, and FIG. 4F is a step F, that is, forming a conductive hole by irradiating the laser 3. The insulating layer 5 on the inclined dummy pattern 1 is removed, and the insulating layer 5 projected from the end dummy pattern 2 by the reflected laser light parallel to the substrate 6 reflected by the inclined dummy pattern 1.
4 is a cross-sectional view showing a step of removing the surface and performing planarization.
4H is a sectional view showing a step H, that is, a step of forming a second-layer conductor pattern, FIG. 4I is a sectional view showing a step I, that is, a multilayer substrate formed by repeating the above process, and FIG. 4) is a sectional view showing a step J, that is, a step of removing the formed dummy pattern, and FIG.
That is, it is a cross-sectional view showing a step of cutting the dicing lines to form individual substrates.

In the present invention, the irradiated laser beam 3
Is reflected by the inclined dummy pattern 1 and is irradiated on the substrate 6 in parallel, and is partially blocked by the end dummy pattern 2, leaving only the extremely thin insulating layer 5 on the desired conductor pattern 4 evenly and eliminating the extra insulation. Planarization is achieved because layer 5 is removed. In this example, an inclined dummy pattern 1 that reflects the laser light 3 and an end dummy pattern 2 that blocks unnecessary reflected laser light are provided in various places on the substrate 6 (each dicing line in this example). Therefore, it is possible to prevent the laser light 3 from being diffused, and it is possible to perform flattening with higher accuracy than in the first aspect.

Further, in the present invention, the conduction hole can be formed at the same time by the laser irradiation shown in FIG. 4F, and the manufacturing process can be omitted, but it may be performed in a separate step. Further, the dummy pattern 2 formed at the end may be used for conduction. Further, the removal process of the dummy pattern 2 shown in FIG. 4 (j) may be omitted if there is no particular problem even if it remains.

The laser irradiation may be a mask transfer,
Positioned spot irradiation may also be used. Furthermore, in order to irradiate the laser beam 3 onto the substrate 6 in parallel with high accuracy, it is better to adjust the irradiation position in advance by using a visible laser or the like.

The inclined dummy pattern 1 and the end dummy pattern 2 are not particularly limited as long as they are materials that reflect the laser beam 3, but metals such as copper, gold, silver and aluminum are preferable. For example, when plated copper is used for the conductor pattern 4, it may be formed of the same material at the same time.

The dicing line shown in FIG. 4A may be formed by any method as long as it can be processed with high accuracy. For example, if the dicing line is formed by etching using the crystal plane of a silicon substrate. It suffices to form a groove having a width of about several hundred μm.

Embodiments 5 and 6 Further, the shape of this groove, that is, the dicing line is shown in FIG.
Not only (a), but at least one side may have an inclination of about 45 °, for example, the shape shown in FIGS. 5 and 6. Further, this inclination angle is not necessarily 45 ° if the angle of the laser beam 3 can be changed.

Example 7. Next, an embodiment of the invention of claim 3 will be described with reference to the drawings. FIG. 7 is a cross-sectional view showing the method of manufacturing a multilayer substrate according to the seventh embodiment in the order of steps, and in this example, a case where no groove is provided along the dicing line is shown. In the figure, reference numeral 2 denotes a dummy pattern which protrudes from the conductor pattern 4 and shields the laser beam. In this example, a plurality of dummy patterns are provided along the dicing line and are similar to the end dummy patterns shown in the fourth embodiment. . Reference numeral 8 denotes a mirror which is inserted in the vicinity of the dummy pattern 2 with an inclination and reflects the laser light 3, and 9 is a block which blocks the laser light 3 and which projects from the dummy pattern 2 and the reflected laser light 3 reaches an adjacent unit substrate. Is being blocked. 7A is a cross-sectional view of step B, that is, the first-layer conductive pattern 4 is formed, FIG. 7B is a cross-sectional view of step C, that is, the dummy pattern 2 is formed along the dicing line, and FIG. Step E, that is, a sectional view in which the insulating layer 5 of the first layer is formed, and FIG. 7D is a sectional view in which the insulating film on the dicing line is removed and a conduction hole is formed by the irradiation of the laser beam 3 in the F1 step, FIG. 7E. Is a cross-sectional view in which the insulating film 5 is flattened by the F2 process, that is, irradiation with the laser beam 3, FIG. 7F is a cross-sectional view in which the process H is performed, that is, the second-layer conductor pattern 4 is formed, and FIG. Step I, that is, a cross-sectional view in which multilayering is performed by repeating the above process, FIG. 7H is a cross-sectional view in which step J, that is, the formed dummy pattern 2 is removed, and FIG. And packaging is a cross-sectional view of forming the individual substrate.

In the present invention, the irradiated laser beam 3
Is reflected by a mirror 8 inserted at an angle and irradiated parallel to the substrate 6, partially shielded by the end dummy pattern 2, leaving only the ultrathin insulating layer 5 on the desired conductor pattern 4 uniformly. Planarization is achieved because the excess insulating layer is removed. In this example, the end dummy patterns 2 that block unnecessary reflected laser light are provided in various places on the substrate 6 (each dicing line in this example), and the mirror 8 and the block 9 are provided for each unit substrate. Since the laser beam 3 is inserted and is irradiated with the laser beam 3 for flattening, it is possible to prevent the laser beam 3 from being diffused, and it is possible to perform the flattening with higher precision than that of the first aspect.

Further, in the present invention, as shown in step F1 of FIG. 7D, the formation of the conductive hole can be simultaneously performed by the irradiation of the laser beam 3 and the manufacturing process can be omitted, but it may be performed in another step. . Further, the dummy pattern 2 formed at the end may be used for conduction.

Irradiation of the laser beam 3 may be mask transfer or spot irradiation with positioning.

Alternatively, a dicing line may be formed in advance before forming a circuit, and cutting may be performed by the process shown in step K of FIG. 7 (i).

Further, in step F2 of FIG.
If the laser beam 3 does not adversely affect the adjacent pattern, the block 9 may be omitted.

The mirror 8 is not particularly limited as long as it is a material that reflects laser light, but a material having a high reflectance, such as a dielectric multilayer film obtained by vapor-depositing a dielectric in multiple layers on a synthetic quartz plate or the like, is used. preferable.

Example 8. Next, another embodiment of the invention of claim 3 will be described with reference to the drawings. FIG. 8 is a cross-sectional view showing a method of manufacturing a multilayer substrate according to the eighth embodiment in the order of steps, and in this example, a case where a groove is provided along a dicing line is shown. In the figure, 2 is an end dummy pattern provided along the dicing line, and 8 is a triangular prism that reflects the laser beam 3 inserted so as to face the end dummy pattern 2. 8A is a sectional view in which a groove is formed on the substrate 6 in step A, FIG. 8B is a sectional view in which the conductor pattern 4 of the first layer is formed in step B, and FIG. 8C is step C in which a dummy is formed. Sectional view in which the pattern 2 is formed, FIG.
Is a cross-sectional view of step E, that is, the first insulating layer 5 is formed,
8E is a cross-sectional view in which the insulating layer on the groove is removed and the conductive hole is formed by irradiating the laser beam 3 in step F1. FIG. 8F shows the insulating layer 5 in which step F2, that is, the laser beam 3 is reflected by the mirror 8. Figure 8 (g)
Is a cross-sectional view of step H, that is, the second-layer conductive pattern 4 is formed, FIG. 8H is a cross-sectional view of step I, which is a multilayered structure by repeating the above process, and FIG. FIG. 8J is a cross-sectional view in which the dummy pattern 2 is removed, and FIG. 8J is a cross-sectional view in which the substrate is formed by cutting the process K, that is, the groove portion.

In the present invention, the irradiated laser beam 3
Is reflected by the mirror 8 and irradiated parallel to the substrate 6,
Partial blocking by the end dummy pattern 2 leaves only the extremely thin insulating layer 5 on the desired conductor pattern 4 uniformly, and the excess insulating layer is removed, so that planarization is achieved. In this example, since the mirror 8 that reflects the laser beam 3 and the end dummy pattern 2 that blocks the unnecessary reflected laser beam are provided everywhere on the substrate 6 (each dicing line in this example), Dispersion of light 3 can be prevented, and claim 1
It is possible to perform flattening with higher accuracy than that of the above.

Further, in the present invention, the conduction hole can be formed at the same time by the irradiation of the laser beam 3 shown in step F1 of FIG. 8E, and the manufacturing process can be omitted, but it may be performed in another step. Further, a dummy pattern formed at the end may be used for conduction.

The laser light irradiation may be mask transfer or spot irradiation with positioning. The mask in step F1 of FIG. 8E and the mask in step F2 of FIG. 8F may be the same.

[0038]

As described above, according to the invention of claim 1, the step of forming a conductor pattern on a substrate, the step of forming an insulating layer on the conductor pattern, and A mask that projects and blocks the laser light is arranged, and the substrate is irradiated with the laser light in parallel and the process of removing the insulating layer protruding from the mask by the laser light that has passed through the mask is performed. The projection of the insulating layer is removed by the laser light, and only the extremely thin insulating film on the conductor pattern remains uniformly, so that planarization is achieved.

Further, according to the invention of claim 2, the step of providing a groove in which at least one surface is inclined at a predetermined angle on the substrate, the step of forming a conductor pattern on the substrate, and the step of forming a conductor pattern on the substrate on the inclined portion of the groove. Forming an end dummy pattern projecting from the conductor pattern and blocking laser light; forming an inclined dummy pattern projecting from the end dummy pattern and reflecting laser light on the inclined part of the groove; on the conductor pattern Step of forming an insulating layer, and irradiating the inclined dummy pattern with a laser beam to obtain a reflected laser beam parallel to the substrate, and the reflected laser beam removes the insulating layer protruding from the end dummy pattern. Since the process is performed, excess laser light is blocked by the end dummy pattern, so only the ultra-thin insulating layer on the conductor pattern remains evenly. It is achieved. Further, if the inclined part dummy pattern and the end part dummy pattern are provided in various places on the substrate, the flattening can be performed with higher accuracy.

Further, according to the invention of claim 3, the step of forming a conductor pattern on the substrate, the step of forming a dummy pattern protruding from the conductor pattern and blocking laser light on the substrate, and an insulating layer on the conductor pattern. Forming process,
And irradiating a laser beam on a mirror inserted in the vicinity of the dummy pattern with a tilt to obtain a reflected laser beam parallel to the substrate, and performing a step of removing the insulating layer protruding from the dummy pattern by the reflected laser beam. Therefore, since the dummy pattern blocks excess laser light, only the extremely thin insulating layer on the conductor pattern remains uniformly, so that planarization is achieved. Furthermore, if mirrors and dummy patterns are provided in various places on the substrate, planarization can be performed with higher accuracy.

[Brief description of drawings]

FIG. 1 is a sectional view showing a method for manufacturing a multilayer substrate according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a method for manufacturing a multilayer substrate according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a method for manufacturing a multilayer substrate according to a third embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a method of manufacturing a multilayer substrate according to a fourth embodiment of the present invention in the order of steps.

FIG. 5 is a sectional view showing an essential part of a method for manufacturing a multilayer substrate according to a fifth embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the main parts of a method for manufacturing a multilayer substrate according to a sixth embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a method of manufacturing a multilayer substrate according to a seventh embodiment of the present invention in the order of steps.

FIG. 8 is a cross-sectional view showing a method of manufacturing a multilayer substrate according to the eighth embodiment of the present invention in the order of steps.

FIG. 9 is a cross-sectional view showing a conventional method of manufacturing a multilayer substrate in the order of steps.

[Explanation of symbols]

 1 Dummy pattern for inclined portion 2 Dummy pattern for end portion 3 Laser light 4 Conductor pattern 5 Insulating layer 6 Substrate 7 Mask 8 Mirror

Claims (3)

[Claims] 1. A step of forming a conductor pattern on a substrate, a step of forming an insulating layer on the conductor pattern, and a mask protruding from the conductor pattern to block laser light are arranged at an end portion of the substrate, and the mask is provided on the substrate. A method for manufacturing a multi-layer substrate, which comprises performing a step of irradiating a laser beam in parallel and removing the insulating layer protruding from the mask by the laser beam passing through the mask. 2. A step of forming a groove in which at least one surface is inclined at a predetermined angle on the substrate, a step of forming a conductor pattern on the substrate, and a laser beam which is projected from the conductor pattern on the substrate facing the inclined portion of the groove to block laser light. A step of forming an end dummy pattern, a step of forming an inclined part dummy pattern projecting from the end dummy pattern and reflecting laser light in the inclined part of the groove, a step of forming an insulating layer on the conductor pattern, and A method of manufacturing a multi-layer substrate, comprising: irradiating a laser beam on a dummy pattern of an inclined portion to obtain a reflected laser beam parallel to the substrate, and removing the insulating layer protruding from the dummy pattern on the edge by the reflected laser beam. 3. A step of forming a conductor pattern on a substrate, a step of forming a dummy pattern on the substrate that protrudes from the conductor pattern and blocks laser light, a step of forming an insulating layer on the conductor pattern, and the vicinity of the dummy pattern. A method for manufacturing a multi-layered substrate, which comprises performing a step of irradiating a laser beam which is tilted and inserted with a laser beam to obtain a reflected laser beam parallel to the substrate, and removing the insulating layer protruding from the dummy pattern by the reflected laser beam. .