TW201611688A - Method for fabricating conductive wiring - Google Patents

Abstract

A method for fabricating conductive wiring includes the steps of: providing a substrate having a conductive layer on the upper surface of the substrate; executing a patterning process for the conductive layer to form a conductive pattern on the upper surface of the substrate, where the conductive pattern has a first recess formed on the side-walls thereof, and the portion of the conductive layer in the first recess remains a residual thickness; forming a sacrificial pattern on the conductive layer and into the first recess, where the sacrificial pattern is protruded from the upper surface of the conductive pattern, and the sacrificial pattern has a second recess formed on the side-walls thereof for exposing the conductive pattern; executing a plating process for the conductive layer, so as to increase the thickness of the conductive pattern; and removing the sacrificial pattern and the portion of the conductive layer in the first recess.

Description

Conductive wiring manufacturing method

The invention relates to a method for manufacturing a conductive wiring, in particular to a method for manufacturing a thick film conductive wiring.

In recent years, with the advancement of electronic technology, wiring boards for mounting semiconductor devices, integrated circuits, and electronic components have been rapidly integrated, high-output, and high-speed, in addition to miniaturization. progress. In particular, the above-described wiring board process has also been developed to miniaturize metal wiring. For example, when a metal wiring such as copper is formed on a substrate, a process such as sputtering film formation and electrolytic plating can be generally employed.

When a thick film metal wiring is formed on a substrate by a conventional technique, the thickness of the metal wiring affects the etching ability, and the etching yield is often affected by the uncleanness of the product, and it is impossible to produce a product having an expected copper thickness and wiring pitch.

Embodiments of the present invention provide a method of fabricating a thick film conductive wiring.

A method for fabricating a conductive wiring according to an embodiment of the present invention provides a substrate having a conductive layer formed on an upper surface thereof. Then, the conductive layer is patterned to form at least one conductive pattern on the upper surface of the substrate, wherein a first groove region is formed between the two conductive patterns, the first groove The depth of the region is less than the thickness of the conductive layer, and a portion of the conductive layer remains in the first recess region. Forming at least one first sacrificial pattern on the conductive layer, wherein the first sacrificial pattern is filled in at least the first recessed region, the first sacrificial pattern protruding in the thickness direction Conductive An upper surface of the pattern forms a second recessed region between the two first sacrificial patterns, and the second recessed region exposes at least a portion of the conductive pattern. Then, the conductive layer is subjected to a plating treatment to thicken the conductive pattern exposed by the second recessed region. Finally, the first sacrificial pattern is removed, and the conductive layer remaining in the first recessed region is removed.

According to the method for fabricating the conductive wiring according to the embodiment of the present invention, the thick film conductive wiring having a high wiring density and a narrow wiring width can be produced without being limited to the etching ability.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

1‧‧‧Substrate

101‧‧‧ Upper surface of the substrate

2, 2'‧‧‧ conductive layer

21, 21'‧‧‧ conductive patterns

201, 201'‧‧‧ upper surface

3, 3'‧‧‧ first groove area

4‧‧‧First Sacrifice Layer

41‧‧‧First Sacrifice Pattern

401‧‧‧ upper surface

5‧‧‧second groove area

6‧‧‧ etching barrier

7‧‧‧Second sacrificial pattern

H1, H3‧‧‧ height

H2‧‧‧ thickness

S1~S6‧‧‧Steps

1A to 1H show the flow of steps of a method of fabricating a conductive wiring according to an embodiment of the present invention.

2 is a flow chart showing the steps of a method of fabricating a conductive wiring according to another embodiment of the present invention.

1A to FIG. 1H, FIG. 1A to FIG. 1H are schematic side views of a substrate having conductive wirings in a manufacturing process according to an embodiment of the present invention, and FIGS. 1A to 1H show conductive wirings according to an embodiment of the present invention. The step flow of the production method.

Referring to FIG. 1A, first, a substrate 1 is provided. The type of the substrate 1 can be selected according to actual needs. For example, when the manufacturing method of the conductive wiring is applied to the semiconductor field, the substrate 1 may be a germanium-containing semiconductor wafer; in other applications, the substrate 1 may be a circuit substrate, and the material of the substrate 1 may be Polycarbonate (PC), polycarbonate and acrylonitrile butadiene-styrene (ABS) or glass fiber-containing materials. The substrate 1 may also be a glass substrate.

As shown in FIG. 1A, the upper surface 101 of the substrate 1 is formed with a conductive layer 2. The conductive layer 2 can be formed by a common conductive material such as copper paste printing, spray coating, electroless plating or sputtering. The coating process may also be carried out by adhering conductive tape or copper foil, but not limited thereto.

Next, in order to pattern the conductive layer 2 to form the conductive pattern 21 on the upper surface 101 of the substrate 1, the conductive layer 2 may be subjected to a first etching treatment. The etching process can be performed by wet etching. In detail, referring to FIGS. 1A through 1C, a sacrificial pattern such as the second sacrificial pattern 7 shown in FIG. 1B may be formed on the conductive layer 2. The second sacrificial pattern 7 may use dry ink, and the manner in which the second sacrificial pattern 7 is formed includes, for example, exposure and development.

Then, the conductive layer 2 is etched through the second sacrificial pattern 7, that is, the exposed portion of the conductive layer 2 that is not covered by the second sacrificial pattern 7 is etched (for example, a copper bite process) to pattern the conductive Layer 2. Finally, the second sacrificial pattern 7 is removed. It is worth mentioning that in the above step of etching the conductive layer 2, only a part of the thickness of the exposed conductive layer 2 is etched, that is, the exposed conductive layer 2 still has a part of the thickness remaining.

In summary, the conductive pattern 21 may be formed on the upper surface 101 of the substrate 1. As shown in FIG. 1C, a first recessed region 3 may be formed between the two conductive patterns 21, and the first recessed region 3 The depth is smaller than the thickness of the conductive layer 2, and a part of the conductive layer 2 remains in the first recessed region 3. The conductive layer 2 formed on the upper surface 101 of the substrate 1 can be fully turned on by the thickness remaining in the first recessed region 3 for subsequent plating treatment.

In another embodiment of the present invention, the etching process may dry-etch a conductive layer 2 by laser etching, and then pattern the conductive layer 2. Specifically, depending on actual needs, for example, depending on the material of the conductive layer 2, the initial thickness of the conductive layer 2, or the residual thickness H2 of the conductive layer 2 in the first recessed region 3, etc., the laser energy and the laser The scan time is adjusted to avoid excessive laser ablation to expose the first recessed region 3 to the upper surface 101 of the substrate 1, or to avoid insufficient laser energy such that the first recessed region 3 does not reach the desired depth. .

Next, referring to FIG. 1D, a first sacrificial pattern 41 is formed on the conductive layer 2, the first sacrificial pattern 41 is filled into at least the first recessed region 3, and the first sacrificial pattern 41 is protruded in the thickness direction. The upper surface 201 of the conductive pattern 21. That is, the height H3 of the first sacrificial pattern 41 in the thickness direction is greater than the height H1 of the conductive pattern 21 in the thickness direction. The height H3 of the first sacrificial pattern 41 in the thickness direction is also the vertical distance from the upper surface 401 of the first sacrificial pattern 41 to the upper surface 101 of the substrate 1, and the height H1 of the conductive pattern 21 in the thickness direction is also a conductive pattern. The vertical distance of the upper surface 201 of 21 to the upper surface 101 of the substrate 1. Further, the sidewall of the first sacrificial pattern 41 forms a second recessed region 5, which may expose a portion of the conductive pattern 21.

An embodiment in which the first sacrificial pattern 41 is formed on the conductive layer 2 will be described in detail below. For example, a first sacrificial layer 4 may be formed over the entire surface of the conductive layer 2, wherein the first sacrificial layer 4 may fill the first recess region 3. Then, the first sacrificial layer 4 is patterned to form the first sacrificial layer 4 into the first sacrificial pattern 41. The first sacrificial layer 4 may use dry ink, and the manner of patterning the first sacrificial pattern 41 includes, for example, exposure and development processes.

Thereby, the first sacrificial pattern 41 can be formed on the conductive layer 2 remaining in the first recessed region 3 corresponding to the first recessed region 3 . As shown in FIG. 1D, in the embodiment, the first sacrificial pattern 41 may fill the first recessed region 3, and the sidewall of the first sacrificial pattern 41 may be partially aligned with the sidewall of the conductive pattern 21, in other words, the second recess. The groove region 5 may expose the conductive pattern 21. On the other hand, the first sacrificial pattern 41 and the conductive pattern 21 are positive and negative complementary, but the invention is not limited thereto.

Next, referring to FIG. 1D to FIG. 1E, the conductive layer 2 is subjected to a plating treatment to thicken the conductive pattern 21 exposed by the second recess region 5. In the present embodiment, the conductive pattern 21 is thickened to a height H3 of the first sacrificial pattern 41 in the thickness direction. In other words, the height of the thickened conductive pattern 21' in the thickness direction may be the same as the height H3 of the first sacrificial pattern 41 in the thickness direction. The height of the thickened conductive pattern 21' in the thickness direction is also the upper surface 201' of the conductive pattern 21' to the upper surface of the substrate 1. The vertical distance of the face 101.

Then, in order to remove the first sacrificial pattern 41 and remove the remaining portion of the conductive layer 2' in the first recessed region 3', an etch stop layer 6 may be formed on the conductive pattern 21' to protect the conductive pattern 21. '. The material of the etching stopper layer 6 includes, for example, tin and lead. Next, under the protection of the etch barrier layer 6, the first sacrificial pattern 41 is removed by deinking, as shown in FIG. 1F. The deinking method is, for example, immersing the first sacrificial pattern 41 with a solvent or stripping the first sacrificial pattern 41 with a plasma.

Next, referring to Fig. 1G, in order to remove the remaining portion of the conductive layer 2' in the first recessed region 3', the conductive layer 2' may be subjected to a second etching treatment under the protection of the etching stopper layer 6. Similar to the first etching process, the second etching process can also be a wet copper bite or a dry laser ablation. The portion of the conductive layer 2' remaining in the first recessed region 3' has only a partial thickness H2, and the portion of the thickness H2 of the conductive layer 2' is, for example, less than 5 micrometers, thus, whether by wet etching or It is a dry etching method, and the remaining portion of the conductive layer 2' in the first recessed region 3' can be easily removed.

Finally, as shown in FIG. 1H, as long as the etching stopper layer 6 is removed, fabrication of the conductive wiring can be completed, and thick film conductive wiring such as thick copper wiring can be obtained. In an embodiment of the invention, the thickness of the thick copper wiring (i.e., the thickness of the conductive pattern 21') may be greater than 50 micrometers, and the wiring pitch of the thick copper wiring may be less than 50 micrometers. In the implementation shown in Figs. 1A to 1H, the wiring pitch of the thick copper wiring is also the width of the first recessed regions 3, 3'.

The above embodiment can be summarized as a method for fabricating a conductive wiring according to another embodiment of the present invention. Please refer to the flowchart of FIG. First, a substrate is provided, and a conductive layer is formed on an upper surface of the substrate (step S1); then, the conductive layer is patterned to form at least one conductive pattern on an upper surface of the substrate, A first groove region is formed between the two conductive patterns, the depth of the first groove region is smaller than the thickness of the conductive layer, and a part of the conductive layer remains in the first groove region ( Step S2); then forming at least one first sacrificial pattern on the conductive layer, Wherein the first sacrificial pattern is filled in at least the first recessed region, the first sacrificial pattern protrudes from the upper surface of the conductive pattern in a thickness direction, between the two first sacrificial patterns Forming a second recessed region, and the second recessed region exposing at least a portion of the conductive pattern (step S3); then, the conductive layer is subjected to a plating process to expose the second recessed region The conductive pattern is thickened (step S4); then, the first sacrificial pattern is removed (step S5); and the conductive layer remaining in the first recessed region is removed (step S6) .

In summary, the embodiments of the present invention provide a method for fabricating a conductive wiring, which utilizes a first etching process performed on the conductive layer 2 to pattern the conductive layer 2, and then utilizes the thickened conductive layer 2'. A second etching process is performed to remove the thickness of the conductive layer remaining in the first recessed regions 3, 3'. In the method of fabricating the conductive wiring, the conductive wiring is formed by the two-stage etching method, and the etching capability is not limited, thereby avoiding the problem of poor conductivity due to incomplete etching.

In addition, the manufacturing method of the conductive wiring utilizes the conductive pattern 21 formed on the upper surface 101 of the substrate 1, and the first stage height of the thick film conductive wiring (for example, thick copper wiring) can be established, and the conductive pattern 21 is used again. The first sacrificial pattern 41 of the upper surface 201 can establish a second stage height of thick film conductive wiring (eg, thick copper wiring). In the method of manufacturing the conductive wiring, a conductive wiring having a high wiring density and a narrow wiring width can be produced.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, equivalent technical changes made by using the present specification and the contents of the drawings are included in the protection scope of the present invention. .

S1~S6‧‧‧Steps

Claims (9)

A method of fabricating a conductive wiring, comprising: providing a substrate, wherein a conductive layer is formed on an upper surface of the substrate; and patterning the conductive layer to form at least one conductive pattern on an upper surface of the substrate Forming a first groove region between the two conductive patterns, the first groove region having a depth smaller than a thickness of the conductive layer, and a portion of the first groove region remaining a conductive layer; forming at least one first sacrificial pattern on the conductive layer, wherein the first sacrificial pattern is filled in at least the first recess region, and the first sacrificial pattern protrudes in a thickness direction a second recessed region is formed between the first and second sacrificial patterns, and the second recessed region exposes at least a portion of the conductive pattern; and the conductive layer is plated And thickening the conductive pattern exposed by the second recessed region; removing the first sacrificial pattern; and removing the conductive layer remaining in the first recessed region. The method of manufacturing the conductive wiring of claim 1, wherein the step of performing the plating process on the conductive layer and before the step of removing the first sacrificial pattern further comprises: on the conductive pattern An etch stop layer is formed. The method of fabricating the conductive wiring of claim 2, wherein the step of removing the conductive layer remaining in the first recessed region further comprises: removing the etch stop layer. The method of manufacturing the conductive wiring of claim 1, wherein the step of forming the first sacrificial pattern on the conductive layer further comprises: Forming a first sacrificial layer on the conductive layer, wherein the first sacrificial layer fills the first recess region; and patterning the first sacrificial layer to cause the The first sacrificial layer forms the first sacrificial pattern on the conductive layer. The method of fabricating the conductive wiring of claim 1, wherein the step of patterning the conductive layer further comprises: forming a second sacrificial pattern on the conductive layer; a sacrificial pattern etching the conductive layer; and removing the second sacrificial pattern. The method for fabricating a conductive wiring according to claim 1, wherein the step of patterning the conductive layer further comprises: ablating the conductive layer with a laser. The method of fabricating the conductive wiring of claim 1, wherein the conductive pattern is thickened to a height of the first sacrificial pattern in a thickness direction. The method of fabricating the conductive wiring of claim 1, wherein the conductive pattern is positively and negatively complementary to the first sacrificial pattern. The method of fabricating the conductive wiring of claim 1, wherein a sidewall of the first sacrificial pattern is aligned with a sidewall portion of the conductive pattern.