Substrate and semiconductor package substrate

Abstract

According to the technical scheme of the utility model, the substrate can be provided, and during the laser processing of forming a concave part and / or a through hole in a processed object by using laser, the intensity distribution of the laser on the processed surface of the processed object is set to be an irradiation shape in which the intensity of the outer side part of the intensity distribution is greater than the intensity of the inner side part of the intensity distribution, so that the processing is carried out. As a result, even if the recess and / or the through hole are / is formed with high resolution, the formed recess and / or the through hole can be prevented from becoming a tapering shape, and a high-definition and complicated wiring pattern can be realized; a substrate capable of realizing a via electrode pattern in which tapering from the front surface to the back surface is suppressed; a semiconductor package substrate having a highly fine and complex metal wiring pattern; and a semiconductor package substrate having a via electrode pattern in which tapering from a front surface to a back surface is suppressed.

Description

[0001] Related divisional applications

[0002] This application is a divisional application of the utility model patent application with the invention name "Substrate and Semiconductor Package Substrate" and application number 202323076597.1. The application date of the original application is November 15, 2023. Technical Field

[0003] The utility model relates to a substrate and a semiconductor packaging substrate. Background Art

[0004] Semiconductor package substrates are actively being developed in line with the trend of shifting from the "More Than More" trend to the system-on-a-chip (SoC) trend that integrates the system into a single chip.

[0005] Furthermore, as the structure of semiconductor package substrates becomes increasingly complex and high-density, devices using excimer lasers are increasingly being used in the manufacture of base substrates thereof.

[0006] For example, Patent Document 1 describes a laser processing method that uses a laser to perform shape processing on a workpiece to a predetermined depth position, wherein the laser power of the laser and the relative movement speed between the workpiece and the laser are increased, and the number of irradiations required for laser processing is reduced, so that the energy per unit length of the laser, which is optimally set according to the workpiece, is still within an energy range that does not penetrate the workpiece even when the laser power increases due to power fluctuations in the laser oscillator.

[0007] Moreover, Patent Document 2 describes a laser processing method, in which a laser having a beam cross-section smaller than that of the excavated area is sequentially irradiated on an excavated area of ​​a workpiece to process the excavated area, and the laser processing method is characterized in that it includes: a first processing step, in which a laser having a beam cross-section of a first shape and forming a first irradiation area corresponding to the first beam cross-section on the workpiece is sequentially irradiated on the entire excavated area; and a second processing step, in which a laser having a beam cross-section of a second shape smaller than the first shape and forming a second irradiation area corresponding to the second beam cross-section on the workpiece is sequentially irradiated on the excavated area, in which, in the first processing step, the laser forming the first irradiation area is sequentially irradiated in a manner such that an overlapping area in which parts of the first irradiation area overlap with each other, and in the second processing step, the laser forming the second irradiation area is sequentially irradiated in a manner such that the second irradiation area is included in an area other than the overlapping area in the excavated area.

[0008] Furthermore, Non-Patent Document 1 describes the formation of high-quality, high-aspect-ratio Si through-holes using a Bessel beam.

[0009] [Prior art literature]

[0010] [Patent Document]

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2009-22978

[0012] Patent Document 2: International Publication No. WO2013 / 094025

[0013] [Non-patent literature]

[0014] Non-Patent Document 1: Koji Sugioka, “Formation of High-Quality, High-Aspect-Ratio Si Through-Hole Using an Optimized Ultrashort-Pulsed Bessel Beam,” FORM TECH REVIEW 2016, Vol. 26 Utility Model Content

[0015] [Problems to be solved by the utility model]

[0016] Conventionally, recesses formed using laser processing have had the following problem: the higher the resolution, the smaller the width of the recess's bottom compared to the width of the recess's opening on the initially processed surface, meaning the tip becomes thinner. A similar problem has also existed with through-holes: the higher the resolution, the smaller the width of the through-hole's lower opening compared to the width of its upper end, meaning the tip becomes thinner. Furthermore, such tapered recesses and / or through-holes are not suitable for forming complex patterns (such as circuit patterns) with high precision.

[0017] In particular, in semiconductor package substrates, metal wiring is sometimes embedded in processed recesses. This increases wiring resistance when high-definition patterns are used. To prevent this, deep processing and a wide width all the way to the bottom are required. This process allows for the production of high-quality semiconductor package substrates with low wiring resistance.

[0018] The present invention is completed in order to solve the above-mentioned problems, and its purpose is to provide a substrate capable of realizing a high-precision and complex wiring pattern, a substrate capable of realizing a through-hole (VIA) electrode pattern with suppressed tapering from the surface to the back side, a semiconductor package substrate with a high-precision and complex metal wiring pattern, and a semiconductor package substrate with a through-hole electrode pattern with suppressed tapering from the surface to the back side.

[0019] [Technical means to solve the problem]

[0020] As a first form of substrate, the utility model provides a substrate used for a semiconductor package substrate, wherein

[0021] The substrate has a rectangular planar shape,

[0022] The surface of the substrate has at least two concave portions adjacent to each other in a cross section perpendicular to the surface.

[0023] The distance between the bottoms of the recesses on the cross section is less than 110% of the width of the bottoms of the recesses.

[0024] The depth of the concave portion on the cross section is 20 μm or less,

[0025] A ratio of the depth of the recessed portion to the width of the bottom of the recessed portion in the cross section is 1.0 or greater.

[0026] By incorporating wiring into the recessed portion of such a substrate, a high-definition and complex wiring pattern can be realized.

[0027] Preferably, the width of the bottom of the recess is 70% or more of the width of the opening of the recess on the surface.

[0028] With such a substrate, when wiring is incorporated into the recess, a wiring pattern with low wiring resistance can be realized. Furthermore, the contact area at the interface between the wiring and the substrate can be increased, thus making it less likely to cause problems such as wiring peeling.

[0029] Preferably, the opening width of the recessed portion on the surface is 20 μm or less.

[0030] With such a substrate, a higher-definition wiring pattern can be realized.

[0031] A ratio of the depth of the recessed portion to the width of the bottom of the recessed portion in the cross section may be 1.1 or greater.

[0032] Alternatively, the ratio of the depth of the recess to the width of the bottom of the recess may be 1.5 or greater.

[0033] Alternatively, the ratio of the depth of the recess to the width of the bottom of the recess may be 2.4 or greater.

[0034] Alternatively, the ratio of the depth of the recess to the width of the bottom of the recess may be 3.4 or greater.

[0035] In the first embodiment of the substrate, the ratio of the depth of the recess to the width of the bottom of the recess may be 1.0 or greater, and may be, for example, 1.1 or greater, 1.5 or greater, 2.4 or greater, or 3.4 or greater.

[0036] For example, the width of the bottom of the recess may be greater than 70% of the width of the opening of the recess, and

[0037] A substrate having a ratio of the depth of the recess to the width of the bottom of the recess of 2.4 or greater.

[0038] If such a substrate is used, a high-definition and low-resistance wiring pattern can be realized more reliably. Moreover, the contact area at the interface between the wiring and the substrate can be increased, thus making it less likely to cause problems such as wiring peeling.

[0039] The recess may also comprise a groove.

[0040] The plurality of recesses may include, for example, grooves extending in a direction parallel to the surface of the substrate. Alternatively, the plurality of recesses may be blind holes having a circular or rectangular planar shape.

[0041] The substrate may have a back surface opposite to the front surface.

[0042] The substrate further includes a through hole extending from the front surface to the back surface.

[0043] With such a substrate, a package substrate further having a through-hole electrode pattern can be realized.

[0044] For example, the width of the upper end opening of the through-hole on the surface can be set to 20 μm or less.

[0045] With such a substrate, a high-definition and high-density through-hole electrode pattern can be realized.

[0046] A ratio of a processed length of the through hole on the rear surface to a width of a lower end opening of the through hole may be set to 1.0 or greater.

[0047] The ratio of the processing length to the width of the lower end opening of the through-hole is not particularly limited, but can be set to 1.0 or more, for example.

[0048] Preferably, the width of the lower end opening of the through hole on the rear surface is 70% or more of the width of the upper end opening of the through hole on the front surface.

[0049] With such a substrate, a through-hole electrode pattern in which tapering from the front surface to the back surface is suppressed can be realized.

[0050] Preferably, the ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more.

[0051] The width of the lower end opening of the through hole is 70% or more of the width of the upper end opening of the through hole on the surface.

[0052] With such a substrate, a high-definition through-hole electrode pattern with suppressed tapering from the front surface to the back surface can be realized.

[0053] For example, the width of the bottom of the recess may be 70% or more of the width of the opening of the recess.

[0054] The ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or more,

[0055] The ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more.

[0056] The width of the lower end opening of the through hole is equal to or greater than 70% of the width of the upper end opening of the through hole on the surface.

[0057] With such a substrate, it is possible to more reliably realize a wiring pattern and a through-hole electrode pattern with high definition and suppressed tapering from the front surface to the back surface.

[0058] Furthermore, as a first aspect of a semiconductor package substrate, the present invention provides a semiconductor package substrate including the substrate of the first aspect of the present invention, wherein a metal wiring is embedded in the recess.

[0059] Such a semiconductor package substrate can realize a semiconductor package having a high-definition, high-density, and complex metal wiring pattern.

[0060] Furthermore, in the present invention, as a second form of substrate, a substrate is provided, which is used as a semiconductor package substrate, wherein

[0061] The substrate has a rectangular planar shape,

[0062] The substrate has a through hole extending from a surface of the substrate to a back surface opposite to the surface.

[0063] The width of the lower end opening of the through hole on the rear surface is 70% or more of the width of the upper end opening of the through hole on the front surface.

[0064] With the substrate of the second embodiment, a semiconductor package having a through-hole electrode pattern in which tapering from the front surface to the back surface is suppressed can be realized.

[0065] Preferably, the width of the upper end opening of the through-hole on the surface is 20 μm or less.

[0066] With such a substrate, a semiconductor package can be realized that has a high-definition, high-density, complex through-hole electrode pattern with suppressed tapering from the front surface to the back surface.

[0067] A ratio of a processed length of the through hole on the rear surface to a width of a lower end opening of the through hole may be 1.0 or greater.

[0068] In the substrate of the second embodiment, the ratio of the processed length of the through hole to the width of the lower end opening can be set to, for example, 1.0 or more.

[0069] Furthermore, in the present invention, as a second form of semiconductor package substrate, a semiconductor package substrate is provided, which includes the substrate including the through hole in the first form of substrate or the second form of substrate, wherein

[0070] The through-holes are subjected to through-hole processing.

[0071] The semiconductor package substrate of the second embodiment can have a high-definition, high-density, and complex through-hole electrode pattern with suppressed tapering from the front surface to the back surface.

[0072] [Effects of the utility model]

[0073] As described above, according to the first aspect of the substrate of the present invention, by embedding the wiring in the recessed portion, a high-definition, high-density, and complex wiring pattern can be realized.

[0074] According to the semiconductor package substrate of the first aspect of the present invention, a semiconductor package having a high-definition, high-density, and complex metal wiring pattern can be realized.

[0075] According to the second aspect of the substrate of the present invention, a semiconductor package having a through-hole electrode pattern in which tapering from the front surface to the back surface is suppressed can be realized.

[0076] According to the second aspect of the semiconductor package substrate of the present invention, it is possible to have a through-hole electrode pattern in which tapering from the front surface to the back surface is suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 (a) to Figure 1 (e) is a schematic diagram showing an example of the laser processing device of the present invention.

[0078] Figure 2 This is a schematic diagram showing an example of laser irradiation in the laser processing method of the present invention.

[0079] Figure 3 (a) to Figure 3 (e) means Figure 2 Schematic diagram of the defocus of laser irradiation.

[0080] Figure 4 This is a schematic diagram showing an example of the laser processing method of the present invention.

[0081] Figure 5 This is a schematic diagram showing another example of laser irradiation in the laser processing method of the present invention.

[0082] Figure 6 This is a schematic cross-sectional view showing an example of a recessed portion that can be formed using the laser processing method of the present invention.

[0083] Figure 7 This is an intensity distribution of an example of laser light that can be used in the laser processing method of the present invention.

[0084] Figure 8 (a) to Figure 8 (d) is a schematic diagram showing an example of a conventional laser processing apparatus.

[0085] Figure 9 This is a schematic diagram showing an example of laser irradiation in a conventional laser processing method.

[0086] Figure 10 (a) to Figure 10 (e) means Figure 9 Schematic diagram of the defocus of laser irradiation.

[0087] Figure 11 This is a schematic diagram showing an example of a conventional laser processing method.

[0088] Figure 12 This is a schematic diagram showing another example of laser irradiation in a conventional laser processing method.

[0089] Figure 13 This is a schematic cross-sectional view showing an example of a recessed portion that can be formed using a conventional laser processing method.

[0090] Figure 14 This is a schematic partial cross-sectional view of an example of a substrate according to the first embodiment of the present invention.

[0091] Figure 15 This is a schematic partial perspective view of another example of the substrate according to the first aspect of the present invention.

[0092] Figure 16 This is a schematic partial cross-sectional view of another example of the substrate according to the first aspect of the present invention.

[0093] Figure 17 This is a schematic partial cross-sectional view of an example of a substrate according to a second embodiment of the present invention.

[0094] Figure 18 This is a schematic partial cross-sectional view of an example of a semiconductor package substrate according to the first aspect of the present invention.

[0095] Figure 19 This is a schematic partial cross-sectional view of an example of a semiconductor package substrate according to a second embodiment of the present invention.

[0096] Figure 20 This is a schematic partial cross-sectional view of another example of the semiconductor package substrate of the present invention.

[0097] Figure 21 This is a schematic plan view of another example of the semiconductor package substrate of the present invention.

[0098] [Explanation of Reference Numerals]

[0099] 1, 2, 3, 3', 4, 4', 5, 5', 6, 6': Laser

[0100] 1a: Center (inside)

[0101] 1b: Periphery (outside)

[0102] 6a: Medial part

[0103] 6b: Outer part

[0104] 10: Laser light source

[0105] 20: Optical system

[0106] 21: Prism

[0107] 21a, 21b: Roof prisms

[0108] 22: Shaping optical system

[0109] 30: Photomask

[0110] 31: Mask alignment camera

[0111] 40: Reflecting Mirror

[0112] 50: Reduced projection optical system

[0113] 60: Carrier

[0114] 61: Alignment camera for workpiece

[0115] 70: Workpiece

[0116] 71: Surface

[0117] 71B: Back

[0118] 72: Processed surface

[0119] 73: Section

[0120] 74: convex part

[0121] 80: Controller

[0122] 90: Semiconductor packaging substrate

[0123] 91: Metal wiring

[0124] 92: Through-hole electrode

[0125] 93: Surface insulation film

[0126] 100, 100': Laser processing equipment

[0127] 200, 200': concave part

[0128] 200A: Open

[0129] 200B: bottom

[0130] 200S, 200U: blind hole

[0131] 200T: Groove

[0132] 201, 201', W b 、W d 、W e :width

[0133] 202, 202', W c :distance

[0134] 300: Through hole

[0135] 300A: Upper opening

[0136] 300B: Lower end opening

[0137] D 200 :Processing depth

[0138] D 300 :Processing length

[0139] F1, F2: imaging points

[0140] U: Focus front

[0141] W a : Opening width DETAILED DESCRIPTION

[0142] As described above, we are seeking: a laser processing method that can suppress the recesses and / or through-holes formed from becoming a tapered shape even when recesses and / or through-holes are formed at high resolution, and can even form a highly precise and complex pattern; a method for manufacturing a substrate that can manufacture a substrate having a highly precise and complex pattern; and the development of a laser processing device that can suppress the recesses and / or through-holes formed from becoming a tapered shape even when recesses and / or through-holes are formed at high resolution, and can even form a highly precise and complex pattern.

[0143] The inventors of the present invention have conducted intensive research on the aforementioned subject and have discovered a laser processing method for forming recesses and / or through-holes in a workpiece using a laser, wherein the processing is performed by setting the intensity distribution of the laser on the workpiece's processed surface to an irradiation shape in which the intensity of the outer portion of the intensity distribution is greater than the intensity of the inner portion. Thus, even when recesses and / or through-holes are formed at a high resolution, the recesses and / or through-holes formed can be suppressed from becoming a tapered shape, and even highly precise and complex patterns can be formed, thereby completing the present invention.

[0144] That is, the present invention is a laser processing method, which uses laser to form recesses and / or through holes in a workpiece, wherein

[0145] The workpiece is processed by setting the intensity distribution of the laser light on the workpiece surface to an irradiation shape in which the intensity of the outer portion of the intensity distribution is greater than the intensity of the inner portion.

[0146] Furthermore, the present invention is a laser processing method for forming recesses and / or through-holes in a workpiece using a laser.

[0147] An optical system is used that shapes the irradiation shape of the laser light into a top-hat type irradiation shape in which the intensity of the laser light is greater at an outer portion than at an inner portion in the intensity distribution of the laser light.

[0148] Furthermore, the present invention is a method for manufacturing a substrate having the recessed portion and / or through-hole, comprising: forming the recessed portion and / or through-hole on the substrate as the workpiece by the laser processing method of the present invention.

[0149] Furthermore, the present invention is a laser processing device for forming a recess and / or a through hole in a workpiece using a laser, the laser processing device comprising:

[0150] a laser light source for oscillating and generating the laser light; and

[0151] The optical system sets the irradiation shape of the laser light so that the intensity distribution of the laser light on the processed surface of the workpiece is greater in intensity at an outer portion than in intensity at an inner portion.

[0152] Furthermore, the present invention is a first embodiment of a substrate used for a semiconductor package substrate, wherein

[0153] The surface of the substrate has at least two concave portions adjacent to each other in a cross section perpendicular to the surface.

[0154] The distance between the bottoms of the recesses on the cross section is less than 110% of the width of the bottoms of the recesses.

[0155] The depth of the concave portion on the cross section is 20 μm or less,

[0156] A ratio of the depth of the recessed portion to the width of the bottom of the recessed portion in the cross section is 1.0 or greater.

[0157] Furthermore, the present invention is a semiconductor package substrate according to a first aspect, including the substrate according to the first aspect of the present invention, wherein a metal wiring is embedded in the recess.

[0158] Furthermore, the present invention is a second form of substrate, which is used for a semiconductor package substrate.

[0159] The substrate has a through hole extending from a surface of the substrate to a back surface opposite to the surface.

[0160] The width of the lower end opening of the through hole on the rear surface is 70% or more of the width of the upper end opening of the through hole on the front surface.

[0161] Furthermore, the present invention is a second-type semiconductor package substrate, which includes a substrate including a through hole in the first-type substrate or a second-type substrate, wherein

[0162] The through-holes are subjected to through-hole processing.

[0163] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0164] [Laser processing equipment]

[0165] Figure 1 (a) to Figure 1 (e) is a schematic diagram showing an example of the laser processing device of the present invention. Figure 1 (a) to Figure 1The laser processing device 100 shown in (e) is a laser processing device 100 that forms a recess and / or a through hole in the workpiece 70 using a laser. Figure 1 (a) to Figure 1 The laser processing device 100 shown in (e) is an example of the laser processing device of the present invention, but the laser processing device of the present invention is not limited to Figure 1 (a) to Figure 1 The device shown in (e).

[0166] Figure 1 (a) to Figure 1 The laser processing apparatus 100 shown in FIG. 7 (e) includes a laser light source 10 for oscillating and generating laser light 1 , and an optical system 20 for converting the intensity distribution and irradiation shape of the laser light 1 on a processing surface of a workpiece 70 .

[0167] Figure 1 (a) to Figure 1 In the laser processing apparatus 100 shown in (e), the optical system 20 includes a prism 21 and a shaping optical system 22. Details will be described below, but the prism 21 is a prism that converts laser light having an intensity distribution in which the laser intensity is highest in the center and decreases in the periphery into a laser light having an irradiation shape in which the intensity of the outer portion of the laser intensity distribution is greater than the intensity of the inner portion. The shaping optical system 22 is a shaping optical system that converts the irradiation shape of the laser light converted by the prism 21 into a top-hat irradiation shape. Figure 1 (a) to Figure 1 In the laser processing apparatus 100 shown in (e), the prism 21 includes a roof prism, but may also include a conical prism.

[0168] Figure 1 (a) to Figure 1 The laser processing apparatus 100 shown in (e) further includes a photomask 30 , a folding mirror 40 , and a reduction projection optical system 50 in order from the optical system 20 to the workpiece 70 in the optical path of the laser processing apparatus 100 .

[0169] The laser processing apparatus 100 further includes a stage 60 for mounting a workpiece 70, and a controller 80 electrically connected to the photomask 30 and the stage 60. On the other hand, the laser processing apparatus 100 further includes a stage 60 for mounting the workpiece 70, and a photomask 30 disposed between the optical system 20 and the stage 60.

[0170] In addition, the photomask 30 , the folding mirror 40 , the reduction projection optical system 50 , the stage 60 , and the controller 80 are arbitrary components of the laser processing apparatus 100 of the present invention.

[0171] The light source 10 that oscillates and generates the laser light 1 is, for example, a light source (laser oscillator) 10 that irradiates (emits) the laser light 1 in a pulsed manner. More specifically, Figure 1 (a) to Figure 1 The laser light source 10 shown in (e) includes an excimer laser oscillator.

[0172] and, Figure 1 (a) to Figure 1 The laser processing apparatus 100 shown in (e) includes: a mask alignment camera 31 as an imaging component for reading characteristic portions of a photomask 30; and a workpiece alignment camera 61 as an imaging component for reading characteristic portions of a workpiece 70. The mask alignment camera 31 is configured to transmit positional information of characteristic portions of the photomask 30 to a controller 80. The workpiece alignment camera 61 is configured to transmit positional information of characteristic portions of the workpiece 70 to the controller 80. The controller 80 is configured to align the relative positions of the workpiece 70 and the photomask 30 based on this positional information. On the other hand, the controller 80 is configured to move the workpiece 70 mounted on the stage 60 in synchronization with the photomask 30.

[0173] [Laser processing method]

[0174] The laser processing method of the present invention can be performed using, for example, the laser processing apparatus of the present invention, but can also be performed using an apparatus other than the laser processing apparatus of the present invention.

[0175] The following describes in detail the Figure 1 (a) to Figure 1 An example of the laser processing method of the present invention performed using the laser processing apparatus 100 shown in (e).

[0176] The laser processing method of the present invention is a laser processing method for forming a recess and / or a through hole in a workpiece 70 using a laser.

[0177] In the laser processing of the present invention, the intensity distribution of the laser on the processed surface of the workpiece 70 is set to an irradiation shape in which the intensity of the outer portion of the intensity distribution is greater than the intensity of the inner portion. Figure 1 (a) to Figure 4 , while giving an example to illustrate this laser processing method.

[0178] First, if Figure 1 (a) to Figure 1 As shown in (e), the laser light source 10 oscillates to generate Figure 1 The irradiation shape of the laser beam 1 is shown in (a). Figure 2As shown, the irradiation pattern of laser light 1 in this example has an intensity distribution in which the laser intensity in the inner portion 1a is greater than the laser intensity in the outer portion 1b. On the other hand, the irradiation pattern of laser light 1 has an intensity distribution in which the laser intensity is greatest in the center (inner portion) 1a and decreases in the peripheral (outer portion) 1b.

[0179] Next, the laser beam 1 is incident on the prism 21 of the optical system 20. The prism 21 is an irradiation shape that converts the intensity distribution of the laser beam 1 into an intensity greater than that of the inner portion. Figure 1 (b)) The prism of laser 2. Figure 1 (a) to Figure 1 In (e), as an example of the prism 21, a prism 21 including four (two pairs) roof prisms is shown. Figure 2 , only two roof prisms 21 a and 21 b related to the irradiation shape of the surface parallel to the paper surface in the laser light 1 are representatively shown.

[0180] The prism 21 is not limited to a roof prism, and for example, a prism including a conical prism may also be used.

[0181] Furthermore, Non-Patent Document 1 discloses the use of an axicon lens as a conical prism, but makes no mention of the prism for converting the laser light into an irradiation shape in which the intensity distribution of the laser light is greater at the outer portion than at the inner portion.

[0182] Next, the light emitted from the prism 21 has Figure 1 (b) and Figure 2 The laser beam 2 of the irradiation shape shown is incident on the shaping optical system 22. Figure 2 As shown, the shaping optical system 22 focuses the components of the laser light 2 toward the imaging point F1, and shapes the irradiation shape of the laser light 2 into Figure 1 The laser beam 3 is set to the top hat type irradiation shape shown in (c).

[0183] The laser beam 3 is incident on the photomask 30 located at the imaging point F1. The photomask 30 has a mask pattern corresponding to the pattern to be processed on the workpiece 70. By scanning and irradiating the workpiece 70 with the laser beam through the photomask 30, recesses and / or through-holes can be formed in the workpiece 70 in the desired pattern.

[0184] emitted from the photomask 30 and having Figure 1 The laser beam 4 having the irradiation shape (top hat shape) shown in (d) is redirected by the folding mirror 40 and enters the reduction projection optical system (projection lens) 50. The effects of using any reduction projection optical system 50 will be described later.

[0185] like Figure 2As shown, the laser light 5 emitted from the reduction projection optical system 50 reaches a surface (initial processing surface) 71 of a workpiece 70 . Figure 2 , an example is shown in which the imaging point F2 of the reduction projection optical system 50 is aligned with the surface 71 of the workpiece 70 . However, the imaging point F2 of the reduction projection optical system 50 is not limited to the surface 71 of the workpiece 70 .

[0186] like Figure 2 As shown, the irradiation shape of the laser 5 irradiated to the surface 71 of the workpiece 70 is as follows: Figure 1 (e) and Figure 2 On the other hand, in the processed surface 72 further processed from the imaging point F2, as shown in FIG. Figure 2 As shown, the intensity distribution of the laser light 6 is set to an irradiation shape in which the intensity of the outer portion 6b of the intensity distribution is higher than the intensity of the inner portion 6a, and processing is performed.

[0187] Figure 1 (a) to Figure 1 (e) and Figure 2 In the example shown, Figure 3 (a)~ Figure 3 As schematically shown in (e) of FIG, as the distance from the imaging point F2 (under focus U) increases, the irradiation shape of the laser light 6 approaches the irradiation shape of the laser light 2 before being shaped by the shaping optical system 22. This is because the intensity distribution of the laser light 6 becomes such that the intensity of the outer portion 6b is greater than the intensity of the inner portion 6a.

[0188] By the laser processing method of the present invention, the intensity distribution of the laser 6 is set to an irradiation shape in which the intensity of the outer portion 6b of the intensity distribution is greater than the intensity of the inner portion 6a in the processed surface 72, thereby processing. Figure 4 As roughly shown in the figure, the recess 200 formed can be suppressed from becoming a tapered shape. By continuing the processing, a through hole with suppressed tapering can be formed. That is, according to the laser processing method of the present invention, it is possible to dig deeper as the processing progresses without tapering. Moreover, in the laser processing method of the present invention, the recess and / or through hole formed as described above can be suppressed from becoming a tapered shape, so that a high-precision and complex pattern can be formed. Moreover, according to the laser processing method of the present invention, even if the recess and / or through hole are formed with high resolution, the recess 200 and / or through hole formed can be suppressed from becoming a tapered shape.

[0189] On the other hand, as shown below Figure 8 (a)~ Figure 11As described above, if the intensity distribution of the laser on the workpiece's processed surface is not set to an irradiation shape in which the intensity of the outer portion of the intensity distribution is greater than that of the inner portion, it is impossible to prevent the formed recesses and / or through holes from becoming tapered.

[0190] Figure 8 (a) to Figure 8 (d) is a schematic diagram showing an example of a conventional laser processing apparatus. Figure 8 (a) to Figure 8 The laser processing device 100' shown in (d) is the same as Figure 1 (a) to Figure 1 The laser processing apparatus 100 shown in (e) is the same.

[0191] Figure 8 (a) to Figure 8 In the laser processing apparatus 100' shown in (d), as shown in FIG. Figure 8 (a) to Figure 8 (d) and Figure 9 As shown, it is oscillated from the laser light source 10 and is Figure 8 The laser beam 1 of the irradiation shape shown in (a) is incident on the forming optical system 22 and becomes Figure 8 The laser 3' has a top hat-shaped irradiation shape as shown in (b). The laser 3' passes through the photomask 30 located at the imaging point F1 of the forming optical system 22 and becomes Figure 8 The laser beam 4' is a top hat type irradiation shape shown in (c). The laser beam 4' is redirected by the folding mirror 40 and enters the reduction projection optical system 50. The laser beam 4' is emitted from the reduction projection optical system 50 and has Figure 8 The laser light 5 ′ having the top-hat irradiation shape shown in FIG. 5 ( d ) reaches the surface 71 of the workpiece 70 located at the imaging point F2 of the reduction projection optical system 50 .

[0192] Next, as the processing progresses, the processed surface 72 moves away from the surface 71 of the workpiece 70 (the front focus U), and the irradiation shape of the laser 6' is as follows: Figure 10 (a)~ Figure 10 As shown in (e), it becomes close to the irradiation shape of the laser light 1 oscillated from the laser light source 10. Therefore, in the processing on the processing surface 72 located at a position away from the surface 71 of the workpiece 70, as shown in (e), Figure 10 (a) to Figure 10 As shown in (e), the intensity distribution of the laser light 6' does not become an irradiation shape in which the intensity of the outer portion of the intensity distribution is higher than the intensity of the inner portion.

[0193] When this method is used for laser processing, for example Figure 11As shown in FIG. 1 , the recessed portion and / or through-hole formed has a tapered shape. In particular, when the recessed portion and / or through-hole are formed at a high resolution, the tapering occurs significantly, making it impossible to perform processing with a high aspect ratio.

[0194] In the laser processing method of the present invention, it is sufficient to process at least a portion of the processed surface 72 of the workpiece 70 by using a laser of an irradiation shape in which the intensity of the outer portion 6b is greater than that of the inner portion 6a. Figure 1 (a) to Figure 1 (e) and Figure 2 As in the illustrated example, a surface (initial processed surface) 71 of a workpiece 70 is processed by the laser beam 5 having a top-hat irradiation pattern.

[0195] In the present invention, for example, Figure 4 As shown, as the processing progresses in the depth direction of the workpiece 70, the shape of the intensity distribution of the laser light 6 on the processing surface 72 of the workpiece 70 is changed, and processing can be performed.

[0196] On the other side, Figure 4 The example can also be said to be an example as described below, that is, as processing advances in the depth direction of the workpiece 70, processing is performed by changing the shape of the intensity distribution of the laser 6 in such a way that the intensity of the outer part 6b of the intensity distribution of the laser 6 becomes greater than the intensity of the inner part 6a.

[0197] By performing the processing as described above, it is possible to more reliably suppress the recessed portion and / or through-hole to be formed from having a tapered shape, and thus it is possible to more reliably form a high-definition and complex pattern.

[0198] However, in the present invention, as long as the intensity distribution of the laser 6 on at least one processed surface 72 of the workpiece 70 can be set to an irradiation shape in which the intensity of the outer part 6b of the intensity distribution is greater than the intensity of the inner part 6a, processing can be performed without continuously changing the laser intensity distribution.

[0199] In the present invention, a photomask 30 can be used to pattern a predetermined recess and / or through-hole. Even when the photomask 30 is used, by setting the intensity distribution of the laser light 6 on the processed surface 72 of the workpiece 70 to an irradiation shape in which the intensity of the outer portion 6b of the intensity distribution is greater than the intensity of the inner portion 6a, the recess and / or through-hole formed can be prevented from becoming a tapered shape, and even a high-definition and complex pattern can be reliably formed. Alternatively, as Figure 5 As shown, in the present invention, the photomask 30 may not be used.

[0200] On the other hand, when the photomask 30 is not used, if the processing is performed without using an irradiation shape in which the intensity of the outer portion 6b of the intensity distribution is greater than the intensity of the inner portion 6a, Figure 11 Similarly, the recess and / or through hole formed are tapered. Figure 12 As shown in FIG, if the intensity distribution is such that the intensity of the outer portion 6b is greater than that of the inner portion 6a, then processing will also be performed. Figure 11 In the illustrated example as well, the recessed portion and / or the through-hole formed are tapered.

[0201] On the other side, refer to Figure 1 (a)~ Figure 4 The example described above can also be said to be a laser processing method, which uses a laser to form a recess and / or a through hole in the workpiece 70, wherein an optical system 20 is used to convert the laser 1 into a laser 2 with an intensity distribution in which the intensity of the outer part is greater than the intensity of the inner part, and then forms the laser 3 into a top hat-type irradiation shape.

[0202] By using this optical system 20 to laser process the workpiece 70, at least a portion of the workpiece 70 away from the surface can be processed using a laser beam 6 irradiation pattern in which the intensity of the outer portion 6b is greater than the intensity of the inner portion 6a. This laser processing method prevents the width of the bottom of the recess from becoming smaller than the width of the recess's opening on the initial processing surface 71, even when forming recesses at high resolution. Furthermore, this laser processing method prevents the width of the lower end opening of the through-hole from becoming smaller than the width of the upper end of the through-hole, even when forming through-holes at high resolution. In other words, the laser processing method of the present invention, as expressed in this aspect, prevents the recesses and / or through-holes from tapering, even when forming recesses and / or through-holes at high resolution, enabling the formation of highly detailed and complex patterns.

[0203] The object 70 to be processed by laser beam processing in the present invention is not particularly limited. For example, a semiconductor package substrate can be used as the object 70 .

[0204] In particular, when processing semiconductor package substrates, patterns often contain a mix of through-holes and recesses, such as through-hole processing and groove processing. In this case, the method of the present invention allows processing to be performed in the same process, without distinguishing between through-hole processing and groove processing. Furthermore, semiconductor package substrates are becoming increasingly dense. Conventional laser drilling methods for through-hole processing, however, increase processing time due to the increased number of holes processed as density increases. In contrast, this method does not increase processing time due to the increased number of holes processed or the higher-definition patterns.

[0205] According to the present invention, for example, ablation processing can be performed on the workpiece 70. In the case of ablation processing, the laser light 5 and the laser light 6 can be freely set within a wavelength and energy density that can perform ablation processing within a range where the energy of the workpiece 70 is absorbed.

[0206] According to the present invention, as described above, it is possible to form a pattern of high-definition recesses and / or through-holes. Specifically, according to the present invention, it is possible to form recesses and / or through-holes having a width of 20 μm or less and with suppressed tapering. Figure 8 (a)~ Figure 12 In the conventional laser processing apparatus 100 ′, it is difficult to form a recessed portion and / or a through-hole having a width of 20 μm or less and suppressed tapering.

[0207] Furthermore, the recesses and / or through-holes formed by the present invention may have a depth of, for example, 20 μm or less. Furthermore, recesses can be formed by making the processing depth less than the thickness of the workpiece 70, and through-holes can be formed by making the processing depth equal to the thickness of the workpiece 70.

[0208] On the other side, according to the present invention, a pattern of recesses and / or through-holes with a high aspect ratio can be formed. According to the present invention, for example, a recess can be formed in which the ratio of the height of the processed portion to the width of the bottom of the recess is greater than 1.0. Moreover, according to the present invention, for example, a recess can be formed in which the ratio of the height of the processed portion to the width of the lower end opening of the through-hole is greater than 1.0. In contrast, in Figure 8 (a)~ Figure 12 In the conventional laser processing apparatus 100 ′, it is difficult to form a recessed portion and / or a through-hole having an aspect ratio of 1.0 or more while suppressing tapering.

[0209] Furthermore, on the other side, according to the present invention, for example, a recess can be formed in which the width of the bottom of the recess is more than 70% of the opening width of the recess on the initial processing surface of the workpiece, and / or a through hole can be formed in which the width of the lower end opening of the through hole is more than 70% of the width of the upper end opening of the through hole on the initial processing surface of the workpiece.

[0210] Furthermore, in the present invention, the concave portion can be formed while suppressing the tapering, so Figure 6 As shown, a plurality of recesses 200 can be formed and the distance 202 between the bottoms of adjacent recesses 200 can be set to be less than 110% of the width 201 of the bottom. Therefore, in the present invention, a plurality of recesses 200 can be formed at a high density.

[0211] On the other hand, in conventional laser processing methods, for example Figure 13 As shown, when forming a plurality of recesses 200 ′, each recess 200 ′ is formed to be tapered, so that the distance 202 ′ between the bottoms of adjacent recesses 200 ′ exceeds 110% of the width 201 ′ of the bottoms, thereby failing to form a plurality of recesses 200 ′ at a high density.

[0212] Hereinafter, arbitrary matters of the laser processing method and the laser processing apparatus of the present invention will be described, but the present invention is not limited to the specific examples described above and the modified examples described below.

[0213] Lasers and laser light sources

[0214] The laser 1 is not particularly limited; for example, an excimer laser can be used. The use of an excimer laser allows for efficient processing of workpieces containing organic materials, such as ABF substrates, enabling highly productive processing. Furthermore, due to its low coherence, the use of an excimer laser enables extremely uniform beam formation.

[0215] Furthermore, the use of excimer lasers allows for highly precise adjustment of processing depth and the width of recesses and / or through-holes compared to solid-state lasers. Excimer lasers are particularly useful for forming recesses such as blind vias and grooves. Therefore, the use of excimer lasers enables high-precision processing of complex concave and convex shapes, such as those on circuit boards.

[0216] The irradiation shape of the laser light 1 oscillated by the laser light source 1 is not limited to Figure 1 (a) to Figure 1 (e), Figure 2 and Figure 5 For example, it can also be the shape shown. Figure 7As shown in the irradiation shape, the intensity distribution is such that the laser intensity is the highest at the center (inner side) 1a and the laser intensity decreases at the periphery (outer side) 1b.

[0217] Scanning irradiation

[0218] In the present invention, the processing can be performed while the laser beams 5 and 6 are scanned relative to the processing surface 71. That is, the laser processing of the present invention can also be set as scanning processing.

[0219] By performing scanning processing, even a workpiece 70 having a large area can be laser processed with high precision.

[0220] Furthermore, by performing scanning processing, even if the number of recessed portions and / or through-holes to be processed increases, an increase in processing time can be prevented.

[0221] The scanning process is performed by, for example, moving the workpiece 70 placed on the stage 60 in synchronization with the photomask 30 .

[0222] This allows laser processing to be performed without moving the laser beams 1 to 6 themselves.

[0223] Furthermore, in this embodiment, the processing area is not limited by the range of the lens, and therefore an area (angle of view) larger than the range of the lens can be processed.

[0224] Furthermore, according to this embodiment, the reduction projection optical system 50 required for irradiation can be reduced, and the laser irradiation position accuracy and temperature controllability can also be performed well. Furthermore, the reduction projection optical system 50 described below can be reduced, so the deformation of the image caused by irradiation is also small.

[0225] Figure 1 (a) to Figure 1 In the laser processing apparatus 100 shown in FIG. 8 (e), the workpiece 70 placed on the stage 60 can be moved in synchronization with the photomask 30 using the controller 80 .

[0226] In more detail, the controller 80 is configured to align the relative positions of the workpiece 70 and the photomask 30 based on the position information of the characteristic portion of the photomask 30 obtained using the mask alignment camera 31 and the position information of the characteristic portion of the workpiece 70 obtained using the workpiece alignment camera 61.

[0227] <Reduction projection optical system>

[0228] Figure 1 (a) to Figure 1In the laser processing apparatus 100 shown in (e), by including the reduction projection optical system 50, the mask pattern formed on the photomask 30 can be enlarged more than the processing pattern actually to be formed on the workpiece.

[0229] By enlarging the mask pattern formed on the photomask 30 compared to the actual processing pattern, the energy of the laser beam 3 irradiated to the photomask 30 can be made smaller than the actual processing energy. If the reduction ratio of the reduction projection optical system 50 is N, the energy of the laser beam irradiated to the mask surface is 1 / (N) compared to the processing energy of the surface of the workpiece 70. 2 ). Thus, thermal drift caused by the energy of the laser beam 3 can be suppressed, thereby suppressing thermal expansion of the photomask 30 and enabling high-precision processing even after a long processing operation.

[0230] Furthermore, since degradation of optical components (for example, the optical system 20 and the photomask 30 ) due to heat from the laser light can be suppressed, the life of the optical components can be extended.

[0231] The reduction projection optical system 50 may include a pair of reduction projection lenses. When the reduction projection optical system 50 is an infinite optical system, the magnification of the reduction projection optical system 50 can be adjusted by, for example, the ratio of the focal lengths of the reduction projection lenses and the distance between the reduction projection lenses.

[0232] The numerical aperture (NA) of the reduction projection lens is preferably selected based on the energy density or processing resolution required for processing the workpiece 70. The NA of the reduction projection lens is preferably 0.12 or greater. In the present invention, even when laser processing is performed at a high NA for high-resolution formation, the resulting recessed portion and / or through-hole can be prevented from having a tapered shape.

[0233] Preferably, the laser processing device 100 of the present invention further includes a temperature adjustment component for adjusting the temperature of the reduction projection optical system 50 .

[0234] By including a temperature control component, the influence of heat caused by the laser energy in the reduction projection optical system 50 can be further suppressed. In the reduction projection optical system 50, the laser light 4 that has passed through the photomask 30 is reduced by 1 / N, so the energy of the laser light passing through the lens portion at the front end of the object becomes N times the energy of the laser light irradiated to the photomask 30. 2 Therefore, in order to suppress this heat energy, the reduction projection optical system 50 is given a temperature adjustment function, thereby suppressing the thermal drift caused by the energy of the laser, and enabling high-precision processing even after a long processing operation.

[0235] Furthermore, the laser processing method and laser processing device 100 of the present invention enable the use of very small-diameter reduction projection lenses. The temperature control components used for the reduction projection lens do not directly apply the temperature control components to the lens itself, but rather cool the sheath that holds the lens. Therefore, as the lens aperture increases, while temperature control can be achieved in the peripheral portion of the lens, the temperature control effect is difficult to spread to the critical central portion, making thermal management difficult. Therefore, even the slightest energy absorption into the lens due to prolonged laser irradiation can easily cause thermal deformation. If the laser processing device 100 includes a temperature control function for the reduction projection optical system 50, the lens aperture can be reduced, thereby suppressing this undesirable condition.

[0236] Furthermore, it is possible to suppress defects caused by laser irradiation on the reduction projection optical system 50 and extend the life of the system.

[0237] [Method for manufacturing substrate]

[0238] The method for manufacturing a substrate of the present invention is a method for manufacturing a substrate having a recess and / or a through hole, which comprises: forming the recess and / or the through hole on a substrate as a workpiece by using the laser processing method of the present invention.

[0239] As described above, the laser processing method of the present invention can form a high-definition and complex pattern. Therefore, if the substrate manufacturing method of the present invention includes the laser processing method of the present invention, a substrate having a high-definition and complex pattern can be manufactured.

[0240] [Substrate]

[0241] The substrate of the present invention is used as a semiconductor package substrate. The substrate of the present invention has a rectangular planar shape. The substrate of the present invention is broadly categorized into two types: a first type having at least two recesses and a second type having a through hole. A substrate having at least two recesses and a through hole can be included in either the first or second type.

[0242] Hereinafter, examples of each of the first and second embodiments of the substrate will be described in more detail with reference to the drawings.

[0243] <First Form>

[0244] Figure 14 A schematic partial cross-sectional view showing an example of a substrate according to a first embodiment of the present invention. Figure 14 The illustrated substrate 70 is a substrate used as a semiconductor package substrate.

[0245] The substrate 70 has at least two concave portions 200 on its surface 71, adjacent to each other in a cross section 73 perpendicular to the surface 71. Each concave portion 200 has an opening 200A on the surface 71 of the substrate 70 and a bottom portion 200B. The substrate 70 has a convex portion 74 between adjacent concave portions 200. The at least two concave portions 200 may have the same shape or different shapes. That is, the width of the opening 200A of the concave portion 200, i.e., the opening width W, is φ(W). a and the width W of the bottom 200B b The processing depth D of the recess 200 may be the same or different. 200 (For example, the depth of the recessed portion 200 in the thickness direction of the substrate 70) may be different in each recessed portion 200, or the same processing depth D may exist. 200 of the concave part.

[0246] The distance W between the bottoms 200B of the recesses 200 on the cross section 73 of the substrate 70 is c is the width W of the bottom 200B of the recess 200 b The width W of the bottom 200B of the concave portion 200 is preferably 100% to 110%, and more preferably 100% to 105%. b is the width W of the bottom 200B of the adjacent recess 200 b Moreover, the distance W between the bottoms 200B of the recesses 200 is c The shortest distance between the bottoms 200B of the recesses 200. In addition, the substrate 70 of the first embodiment of the present invention only needs to have a distance W between the bottoms 200B of the recesses 200. c is the width W of the bottom 200B of the recess 200 b It suffices to have at least two recesses 200 that are less than 110% of the above, and may also include recesses that do not satisfy this relationship.

[0247] Furthermore, in the substrate 70, the depth D of the recessed portion 200 on the cross section 73 is 200 Furthermore, in the substrate 70, the depth D of the recessed portion 200 on the cross section 73 is 200 The width W of the bottom 200B of the recess 200 b The ratio (D 200 / W b ) is greater than 1.0.

[0248] In this substrate 70 , the distance W between the bottoms 200B of the recesses 200 is c is the width W of the bottom 200B of the recess 200 b 110% or less, and the depth D of the recess 200 is 200 The depth D of the concave portion 200 is less than 20 μm.200 The width W of the bottom 200B of the recess 200 b The ratio (D 200 / W b ) satisfies 1.0 or more, so the width W b The width is set to be very small. Therefore, such substrate 70 can have a high-definition recess pattern. In addition, by installing wiring, such as metal wiring, into such recess 200 of substrate 70, a high-definition and complex wiring pattern can be realized.

[0249] The substrate of the first embodiment can be manufactured, for example, by the laser processing method or substrate manufacturing method of the present invention described above. Furthermore, the substrate of the first embodiment can be manufactured, for example, by using the laser processing device of the present invention described above.

[0250] Therefore, for example, the width W of the bottom 200B of the recess 200 may be b It is set to 70% or more of the opening width Wa of the recessed portion 200 on the surface 71 , preferably 80% or more, and more preferably 90% or more.

[0251] In this type of substrate 70, recess 200 is not tapered but rather resembles a cylindrical barrel. Therefore, when wiring is inserted into recess 200, the wiring exhibits low resistance. Consequently, this type of substrate 70 enables the realization of a wiring pattern with low wiring resistance. Furthermore, since the contact area between the wiring and the substrate is increased, problems such as wiring peeling are less likely to occur.

[0252] Ideally, the width W of the bottom 200B of the recess 200 is b With opening width W a Equal (100%).

[0253] Furthermore, for example, it is preferable that the opening width W of the recess 200 on the surface 71 is a Less than 20 μm.

[0254] If such a substrate 70 is used, a higher-definition wiring pattern can be realized. The lower limit is not particularly limited. For example, the opening width W of the recess 200 on the surface 71 is a The thickness can be set to 1 μm or more and 20 μm or less.

[0255] In the first embodiment of the substrate 70, the ratio D 200 / W b It only needs to be 1.0 or more, and may be, for example, 1.1 or more, 1.5 or more, 2.4 or more, or 3.4 or more. 200 / W b There is no particular upper limit on D 200 / Wb For example, it can be set to 10.0 or less.

[0256] The opening width W of the recess 200 on the surface 71 is a It can be set to 20 μm or less.

[0257] If this type of substrate is used, a higher-definition wiring pattern can be realized. a The lower limit of is not particularly limited, and can be, for example, 1 μm or more.

[0258] For example, the first embodiment of the substrate 70 may also have a width W of the bottom 200B of the recess 200. b is the opening width W of the recess 200 a More than 70% of the depth D of the concave portion 200 200 The width W of the bottom 200B of the recess 200 b The ratio of the substrate is 2.4 or more.

[0259] With such a substrate 70 , a high-definition, complex, and low-resistance wiring pattern can be realized more reliably.

[0260] The recess 200 may also include, for example Figure 15 The groove 200T is as shown in the three-dimensional view of the substrate 70. The groove 200T extends in a direction parallel to the surface 71 of the substrate 70. A plurality of grooves 200T may also be formed as shown in FIG. Figure 15 As shown as an example in FIG, the directions of extension are different from each other.

[0261] The recess 200 is not limited to the groove 200T. Figure 15 As shown in the example, the blind hole 200S having a rectangular surface shape or the blind hole 200U having a circular surface shape is included. The recessed portion 200 having other surface shapes may also be included.

[0262] In D 200 / W b When the concave portion 200 having a width W greater than 1.0 is a trench 200T, the width W b and opening width W a The width of the trench 200T in the direction perpendicular to the direction in which the trench extends is defined as: 200 / W b When the concave portion 200 having a value of 1.0 or greater is a blind hole 200S having a rectangular surface shape, the minimum width in the surface shape is set to width W. b and opening width W a In the D 200 / W b When the plurality of recesses 200 having a value of 1.0 or greater are blind holes 200U having a circular surface shape, the diameter of the circle is defined as the width W.b and opening width W a If the surface shape is an ellipse, its short diameter is set to width W. b and opening width W a .

[0263] In addition, as previously described, the substrate 70 of the first embodiment of the present invention only needs to have a 200 / W b It is sufficient for at least two concave portions 200 to have a value greater than 1.0, and it is not necessary for all concave portions to have a value greater than D 200 / W b Satisfy 1.0 or above.

[0264] The processing depth D of the recessed portion 200 on the cross section 73 is 200 (For example, the depth of the recessed portion 200 in the thickness direction of the substrate 70) may be different in each recessed portion 200, or may have the same processing depth D 200 of the concave part. Processing depth D of recess 200 200 For example, the thickness can be set to 5 μm or more and 20 μm or less.

[0265] In the modified example, Figure 16 As shown, the substrate 70 of the first embodiment may include a back surface 71B opposite to the front surface 71 of the substrate 70 , and further include a through hole 300 penetrating from the front surface 71 to the back surface 71B.

[0266] With such a substrate 70 , a package substrate further having a through-hole electrode pattern can be realized.

[0267] For example, it is preferable that the width W of the upper end opening 300A of the through hole 300 on the surface 71 is d Set it to 20 μm or less.

[0268] With such a substrate 70 , a high-definition and high-density through-hole electrode pattern can be realized.

[0269] Width W of the upper opening 300A d The lower limit of is not particularly limited, and can be, for example, 1 μm or more.

[0270] The processing length D of the through hole 300 on the back surface 71B 300 The width W of the lower end opening 300B of the through hole 300 is e The ratio can be set to 1.0 or more.

[0271] Processing length D 300 The width W of the lower end opening 300B of the through hole 300 is e The upper limit of the ratio is not particularly limited, and can be, for example, 1.0 or more and 10.0 or less.

[0272] The substrate 70 having such through-holes 300 can also be formed by, for example, the laser processing method or substrate manufacturing method of the present invention described above. Furthermore, the substrate 70 can be manufactured using, for example, the laser processing apparatus of the present invention described above.

[0273] Therefore, the width W of the lower end opening 300B of the through hole 300 on the rear surface 71B is e The width W of the upper opening 300A of the through hole 300 on the surface 71 may be set to d More than 70% of the substrate 70 preferably has such a through hole 300. The substrate 70 having such a through hole 300 and at least two recesses 200 described above is a first type of substrate and a second type of substrate.

[0274] In this substrate 70, through-hole 300 is not tapered but rather resembles a cylindrical barrel. Therefore, when through-hole processing is performed on this through-hole 300, the resulting through-hole electrode exhibits low resistance. Furthermore, since the contact area between the wiring and the substrate is increased, problems such as wiring peeling are less likely to occur. Consequently, this modified substrate 70 can achieve a highly detailed, complex, and low-resistance through-hole electrode pattern.

[0275] Ideally, the width W of the lower end opening 300B of the through hole 300 is e The width W of the upper opening 300A d The width W of the lower opening 300B of the through hole 300 is equal (100%). e The width W of the upper opening 300A can be set to d The content of the present invention is 70% or more, preferably 80% or more, more preferably 90% or more.

[0276] For example, in the first embodiment of the substrate 70, the processing length D of the through hole 300 on the back surface 71B may be 300 The width W of the lower end opening 300B of the through hole 300 is e The ratio is greater than 1.0, and the width W of the lower end opening 300B of the through hole 300 is e is the width W of the upper end opening 300A of the through hole 300 on the surface 71 d This form is preferred.

[0277] Such a substrate 70 can reliably realize a high-definition through-hole electrode pattern with suppressed tapering from the front to the back surface. Furthermore, since the contact area at the interface between the wiring and the substrate can be increased, defects such as wiring peeling are less likely to occur.

[0278] Furthermore, for example, the substrate 70 of the first embodiment may be a substrate in which the width W of the bottom 200B of the recess 200 is b is the opening width W of the recess 200 a more than 70%, the depth D of the recess 200 200 The width W of the bottom 200B of the recess 200 b The ratio is 2.4 or more, and the processing length D of the through hole 300 on the back surface 71B is 300 The width W of the lower end opening 300B of the through hole 300 is e The ratio is greater than 1.0, and the width W of the lower end opening 300B of the through hole 300 is e is the width W of the upper end opening 300A of the through hole 300 on the surface 71 d More than 70% of the total.

[0279] Such a substrate 70 can more reliably realize a high-definition through-hole electrode pattern with suppressed tapering from the front to the back surface. Furthermore, since the contact area at the interface between the wiring and the substrate can be increased, defects such as wiring peeling are less likely to occur.

[0280] The planar shape of the through hole 300 is not particularly limited. When the through hole 300 has a rectangular surface shape, the minimum width in the surface shape is defined as width W. d and width W e When the through hole 300 has a circular surface shape, the diameter of the circle is defined as the width W. d and width W e If the surface shape is an ellipse, its short diameter is set to width W. d and width W e .

[0281] Second Form

[0282] Figure 17 A schematic partial cross-sectional view showing an example of a substrate according to a second embodiment of the present invention. Figure 17 The illustrated substrate 70 is a substrate used as a semiconductor package substrate.

[0283] The substrate 70 has a through hole 300 extending from the surface 71 to the back surface 71B opposite to the surface 71, and a width W of a lower end opening 300B of the through hole 300 on the back surface 71B is e is the width W of the upper end opening 300A of the through hole 300 on the surface 71 d More than 70% of the total.

[0284] In this type of substrate 70, the through-hole 300 is not tapered but rather resembles a cylindrical tube. Therefore, when through-hole processing is performed on this through-hole 300, the resulting through-hole electrode exhibits low resistance. Therefore, this type of substrate 70 can achieve a low-resistance through-hole electrode pattern.

[0285] Furthermore, the through hole 300 is not in a tapered shape, so there is no need to ensure the width W of the lower end opening 300B of the through hole 300. e The width W of the upper end opening 300A of the through hole 300 is d Therefore, this type of substrate 70 can also realize a high-definition and complex through-hole pattern.

[0286] Ideally, the width W of the lower end opening 300B of the through hole 300 is e The width W of the upper opening 300A d The width W of the lower opening 300B of the through hole 300 is equal (100%). e The width W of the upper opening 300A can be set to d The content of the present invention is 70% or more, preferably 80% or more, more preferably 90% or more.

[0287] There may be one through hole 300 or more through holes 300. In the case of a plurality of through holes 300, the width W of the plurality of through holes 300 is d and width W e It can be the same or different.

[0288] The planar shape of the through hole 300 is not particularly limited. When the through hole 300 has a rectangular surface shape, the minimum width in the surface shape is defined as width W. d and width W e When the through hole 300 has a circular surface shape, the diameter of the circle is defined as the width W. d and width W e If the surface shape is an ellipse, its short diameter is set to width W. d and width W e .

[0289] Such a substrate 70 can be formed, for example, by the laser processing method of the present invention described above or the substrate manufacturing method of the present invention. Furthermore, the substrate 70 can be manufactured, for example, using the laser processing device of the present invention described above.

[0290] Preferably, the width W of the upper end opening 300A of the through hole 300 on the surface 71 is d Less than 20 μm.

[0291] With such a substrate 70 , a semiconductor package having a high-definition through-hole electrode pattern can be realized.

[0292] Width W of the upper opening 300A d The lower limit of is not particularly limited, and can be, for example, 1 μm or more.

[0293] The processing length D of the through hole 300 on the back surface 71B 300 The width W of the lower end opening 300B of the through hole 300 is e The ratio can be set to 1.0 or more, for example. 300 The width W of the lower end opening 300B of the through hole 300 is e The ratio is not particularly limited, and can be, for example, 1.0 or more and 10.0 or less.

[0294] The second embodiment of the substrate 70 may further include a recessed portion that does not penetrate from the surface 71 to the back surface 71B. Figure 16 The case shown is also the following substrate 70, that is, it may include at least two recesses 200, and the depth D of the recess 200 on the cross section 73 is 200 The depth D of the concave portion 200 on the cross section 73 is 20 μm or less. 200 The width W of the bottom 200B of the recess 200 b The ratio (D 200 / W b ) is 1.0 or more. This type of substrate 70 may also be referred to as a first type of substrate.

[0295] Furthermore, as previously described, the substrate of the present invention can be formed, for example, by the laser processing method of the present invention or the substrate manufacturing method of the present invention, but can also be manufactured using other methods. Furthermore, the substrate of the present invention can be manufactured, for example, using the laser processing apparatus of the present invention, but can also be manufactured using other apparatuses.

[0296] [Semiconductor package substrate]

[0297] The semiconductor package substrate of the present invention is a substrate used for semiconductor packaging. The so-called semiconductor package is, for example, a component that plays the following role, that is, protecting semiconductor elements from the external environment and providing external connection wiring terminals when the elements are mounted on a printed wiring board, etc. In other words, the semiconductor package substrate is a substrate used for semiconductor packaging, and it may or may not be equipped with semiconductor elements. Moreover, it may or may not include a component that protects the semiconductor elements. Below, as an example, with reference to the accompanying drawings, a substrate that does not include a semiconductor element and a component that protects the semiconductor element is described.

[0298] Figure 18 A schematic partial cross-sectional view showing an example of a semiconductor package substrate according to a first embodiment of the present invention.

[0299] Figure 18 The semiconductor package substrate 90 shown includes a side reference Figure 14 The substrate 70 of an example of the first embodiment of the present invention will be described above.

[0300] and, Figure 18 The semiconductor package substrate 90 shown is Figure 14 The metal wiring 91 is embedded in the recess 200 shown. On the other side, the semiconductor package substrate 90 may include the metal wiring 91 sandwiched between the protrusions 74 of the substrate 70.

[0301] As previously described, the presence of recessed portion 200 in substrate 70 enables the realization of a highly detailed and complex wiring pattern. Therefore, using this type of semiconductor package substrate 90 enables the realization of a semiconductor package having a highly detailed and complex pattern of metal wiring 91. Furthermore, since the contact area at the interface between the wiring and the substrate can be increased, problems such as wiring peeling are less likely to occur.

[0302] Figure 19 A schematic partial cross-sectional view showing an example of a semiconductor package substrate according to a second embodiment of the present invention.

[0303] Figure 19 The semiconductor package substrate 90 shown includes Figure 17 The substrate 70 is an example of the second embodiment of the present invention.

[0304] Figure 19 In the semiconductor package substrate 90 shown, through-hole processing is performed on the through-hole 300. More specifically, a through-hole electrode 92 is formed on the surface of the substrate 70 that defines the through-hole 300.

[0305] For the reasons described above, the second-type substrate 70 can realize a high-definition through-hole electrode pattern with suppressed tapering from the front to the back. Therefore, the second-type semiconductor package substrate 90 can have a high-definition through-hole electrode pattern with suppressed tapering from the front to the back.

[0306] in addition, Figure 19 In the embodiment, the through-hole electrode 92 includes a hollow portion (through hole 300 ), but the through-hole electrode 92 may not include a hollow portion.

[0307] For example, Figure 20As shown, the second form of the semiconductor package substrate 90 may further include embedded metal wiring 91. The metal wiring 91 is embedded in the recess 200 described in the first form of the substrate. Figure 20 The semiconductor package substrate 90 of the illustrated example can also be referred to as an example of a first type of semiconductor package substrate.

[0308] In addition, the size of the metal wiring 91 can be as Figure 20 Although they are different as shown, the same metal wiring may also exist.

[0309] The semiconductor package substrate 90 of the present invention may also be Figure 21 As shown in the example of the plan view in FIG, a surface insulating film 93 is also included. The surface insulating film 93 can hide the metal wiring 91 as shown by the dotted line. Figure 21 As shown, a portion of the through-hole electrode 92 is exposed.

[0310] According to the present invention, for example Figure 21 As shown, a plurality of metal wirings 91 can be formed between the through-hole electrodes 92 as a high-definition and complex pattern.

[0311] In addition, the processing target substrate of the present invention may be provided with circuits such as metal wiring and resist, or may not be provided with these.

[0312] Furthermore, the substrate to be processed by the laser processing method of the present invention, the substrate of the present invention, and the semiconductor package substrate of the present invention each have a rectangular planar shape.

[0313] This specification includes the following aspects.

[0314] [1] A laser processing method for forming a recess and / or a through hole in a workpiece using a laser, wherein the processing is performed by setting the intensity distribution of the laser on the workpiece surface to an irradiation shape in which the intensity of the outer portion of the intensity distribution is greater than the intensity of the inner portion.

[0315] [2] The laser processing method according to [1], wherein processing is performed by changing the shape of the intensity distribution of the laser light on the processed surface of the workpiece as processing progresses in the depth direction of the workpiece.

[0316] [3] The laser processing method according to [2], wherein processing is performed by changing the shape of the intensity distribution of the laser light in such a manner that the intensity of the outer portion of the intensity distribution of the laser light becomes greater than the intensity of the inner portion as processing proceeds toward the depth direction of the workpiece.

[0317] [4] The laser processing method according to [3], wherein a laser having an intensity distribution in which the laser intensity is maximum at the center and decreases at the periphery is passed through a prism, thereby processing is performed by changing the shape of the intensity distribution of the laser so that the intensity of the outer portion of the intensity distribution of the laser becomes greater than the intensity of the inner portion as processing proceeds toward the depth direction of the workpiece.

[0318] [5] The laser processing method according to [4], wherein a prism including a roof prism or a conical prism is used as the prism.

[0319] [6] A laser processing method for forming a recess and / or a through hole in a workpiece using a laser, wherein an optical system is used to shape the irradiation shape of the laser into a top hat-type irradiation shape in which the intensity of the outer portion of the laser is greater than the intensity of the inner portion in the intensity distribution of the laser.

[0320] [7] The laser processing method according to [6], wherein the initial processing surface of the workpiece is processed using the laser with the top hat type irradiation shape, and at least a portion of the workpiece other than the initial processing surface is processed using the laser with an irradiation shape in which the intensity of the outer portion is greater than the intensity of the inner portion.

[0321] [8] The laser processing method according to any one of [1] to [7], wherein a semiconductor package substrate is processed as the workpiece to form a recess and / or a through hole in the semiconductor package substrate.

[0322] [9] The laser processing method according to any one of [1] to [8], wherein the laser light is oscillated using an excimer laser oscillator.

[0323]

[10] The laser processing method according to any one of [1] to [9], wherein the laser light is irradiated onto the workpiece through a photomask.

[0324]

[11] The laser processing method according to any one of [1] to

[10] , wherein processing is performed while the laser beam is scanned relative to the surface to be processed.

[0325]

[12] The laser processing method according to any one of [1] to

[11] , wherein ablation processing is performed.

[0326]

[13] The laser processing method according to any one of [1] to

[12] , wherein the recess and / or through-hole is formed to have a width of 20 μm or less.

[0327]

[14] The laser processing method according to any one of [1] to

[13] , wherein the recess and / or through-hole is formed to have a depth of 20 μm or less.

[0328]

[15] A laser processing method according to any one of [1] to

[14] , wherein the recess and / or through hole is formed such that the ratio of the processing portion height to the width of the bottom of the recess or the width of the lower end opening of the through hole is greater than 1.0.

[0329]

[16] A laser processing method according to any one of [1] to

[15] , wherein the width of the bottom of the recess is greater than 70% of the opening width of the recess on the initial processing surface of the workpiece, and / or the width of the lower end opening of the through hole is greater than 70% of the width of the upper end opening of the through hole on the initial processing surface of the workpiece.

[0330]

[17] The laser processing method according to any one of [1] to

[16] , wherein a plurality of the recesses are formed, and the distance between the bottoms of adjacent recesses is set to be less than 110% of the width of the bottoms.

[0331]

[18] A method for manufacturing a substrate having a recess and / or a through hole, comprising: forming the recess and / or the through hole on the substrate as the workpiece by the laser processing method described in any one of [1] to

[17] .

[0332]

[19] A laser processing device that uses laser to form a recess and / or a through hole in a workpiece, the laser processing device comprising: a laser light source that oscillates and generates the laser; and an optical system that sets the irradiation shape of the laser to an irradiation shape in which the intensity distribution of the laser on the workpiece surface is greater than the intensity of the inner portion of the intensity distribution.

[0333]

[20] The laser processing device according to

[19] , wherein the optical system includes: a prism that converts a laser having an intensity distribution in which the laser intensity is the largest in the center and decreases in the periphery into the laser having an irradiation shape in which the intensity of the outer portion of the intensity distribution of the laser becomes greater than the intensity of the inner portion; and a forming optical system that converts the irradiation shape of the laser converted by the prism into a top-hat type irradiation shape.

[0334]

[21] The laser processing device according to

[20] , wherein the prism includes a prism including a roof prism or a conical prism.

[0335]

[22] The laser processing device according to any one of

[19] to

[21] , wherein the laser light source includes an excimer laser oscillator.

[0336]

[23] The laser processing device according to any one of

[19] to

[22] further includes: a stage on which the workpiece is placed; and a photomask arranged between the optical system and the stage.

[0337]

[24] The laser processing device according to

[23] further includes a controller configured to move the workpiece placed on the stage in synchronization with the photomask.

[0338]

[25] A substrate used for a semiconductor packaging substrate, wherein the surface of the substrate has at least two concave portions adjacent to each other in a cross section perpendicular to the surface, the distance between the bottoms of the concave portions in the cross section is less than 110% of the width of the bottoms of the concave portions, the depth of the concave portions in the cross section is less than 20 μm, and the ratio of the depth of the concave portions in the cross section to the width of the bottoms of the concave portions is greater than 1.0.

[0339]

[26] The substrate according to

[25] , wherein the width of the bottom of the recess is 70% or more of the opening width of the recess on the surface.

[0340]

[27] The substrate according to

[26] , wherein the opening width of the recessed portion on the surface is 20 μm or less.

[0341]

[28] The substrate according to any one of

[25] to

[27] , wherein the ratio of the depth of the recess in the cross section to the width of the bottom of the recess is greater than or equal to 1.1.

[0342]

[29] The substrate according to any one of

[25] to

[28] , wherein the ratio of the depth of the recess to the width of the bottom of the recess is greater than or equal to 1.5.

[0343]

[30] The substrate according to any one of

[25] to

[29] , wherein the ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or greater.

[0344]

[31] The substrate according to any one of

[25] to

[30] , wherein the ratio of the depth of the recess to the width of the bottom of the recess is 3.4 or greater.

[0345]

[32] The substrate according to

[25] , wherein the width of the bottom of the recess is 70% or more of the width of the opening of the recess,

[0346] A ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or greater.

[0347]

[33] The substrate according to any one of

[25] to

[32] , wherein the recess includes a groove.

[0348]

[34] The substrate according to any one of

[25] to

[32] , wherein the substrate has a back surface opposite to the front surface, and the substrate further has a through hole extending from the front surface to the back surface.

[0349]

[35] The substrate according to

[34] , wherein the width of the upper end opening of the through hole on the surface is 20 μm or less.

[0350]

[36] The substrate according to

[34] or

[35] , wherein the ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is greater than 1.0.

[0351]

[37] A substrate according to any one of

[34] to

[36] , wherein the width of the lower end opening of the through hole on the back surface is greater than 70% of the width of the upper end opening of the through hole on the surface.

[0352]

[38] The substrate according to

[34] or

[35] , wherein the ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more,

[0353] The width of the lower end opening of the through hole is 70% or more of the width of the upper end opening of the through hole on the surface.

[0354]

[39] The substrate according to

[34] , wherein the width of the bottom of the recess is 70% or more of the width of the opening of the recess,

[0355] The ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or more,

[0356] The ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more.

[0357] The width of the lower end opening of the through hole is 70% or more of the width of the upper end opening of the through hole on the surface.

[0358]

[40] A semiconductor package substrate comprising the substrate described in any one of

[25] to

[39] , wherein a metal wiring is embedded in the recess.

[0359]

[41] A substrate used for a semiconductor packaging substrate, wherein the substrate has a through hole extending from a surface of the substrate to a back surface opposite to the surface, and the width of the lower end opening of the through hole on the back surface is more than 70% of the width of the upper end opening of the through hole on the surface.

[0360]

[42] The substrate according to

[41] , wherein the width of the upper end opening of the through hole on the surface is 20 μm or less.

[0361]

[43] The substrate according to

[41] or

[42] , wherein the ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is greater than 1.0.

[0362]

[44] A semiconductor package substrate comprising the substrate described in any one of

[34] to

[39] and

[41] to

[43] , wherein the through hole is subjected to through-hole processing.

[0363] The present invention is not limited to the above-described embodiments, which are merely examples, and any content having substantially the same structure and achieving the same functions and effects as the technical concept described in the claims of the present invention is included within the technical scope of the present invention.

Claims

1. A substrate, characterized in that is used for a semiconductor package substrate, the substrate, Having a rectangular plan shape, The surface of the substrate has at least two concave portions adjacent to each other in a cross section perpendicular to the surface. The distance between the bottoms of the adjacent recesses in the cross section is less than 110% of the width of the bottoms of the recesses. The depth of the concave portion on the cross section is 20 μm or less, The ratio of the depth of the concave portion to the width of the bottom of the concave portion in the cross section is 1.0 or greater, The recess comprises a groove, The substrate has a back surface opposite to the front surface. The substrate further includes a through hole extending from the front surface to the back surface.

2. The substrate according to claim 1, wherein The opening width of the recessed portion on the surface is 20 μm or less.

3. The substrate according to claim 1, wherein A ratio of the depth of the recessed portion to the width of the bottom of the recessed portion in the cross section is 1.1 or greater.

4. The substrate according to claim 1, wherein A ratio of the depth of the recess to the width of the bottom of the recess is 1.5 or greater.

5. The substrate according to claim 1, wherein A ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or greater.

6. The substrate according to claim 1, wherein A ratio of the depth of the recess to the width of the bottom of the recess is 3.4 or greater.

7. The substrate according to claim 1, wherein The width of the bottom of the recess is greater than 90% of the width of the opening of the recess. A ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or greater.

8. The substrate according to claim 1, wherein The width of the upper end opening of the through-hole on the surface is 20 μm or less.

9. The substrate according to claim 1, wherein A ratio of a processed length of the through hole on the rear surface to a width of a lower end opening of the through hole is 1.0 or greater.

10. The substrate according to claim 1, wherein The width of the lower end opening of the through hole on the rear surface is equal to or greater than 80% of the width of the upper end opening of the through hole on the front surface.

11. The substrate according to claim 1, wherein The ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more. The width of the lower end opening of the through hole is equal to or greater than 80% of the width of the upper end opening of the through hole on the surface.

12. The substrate according to claim 1, wherein The width of the bottom of the recess is greater than 90% of the width of the opening of the recess. The ratio of the depth of the recess to the width of the bottom of the recess is 2.4 or more, The ratio of the processed length of the through hole on the back surface to the width of the lower end opening of the through hole is 1.0 or more. The width of the lower end opening of the through hole is equal to or greater than 80% of the width of the upper end opening of the through hole on the surface.

13. A semiconductor package substrate, characterized in that: The semiconductor package substrate comprises a substrate according to any one of claims 1 to 12, Metal wiring is embedded in the recess.

14. The semiconductor package substrate according to claim 13, wherein A semiconductor element is mounted.

15. The semiconductor package substrate according to claim 13, wherein It has external connection wiring terminals.

16. A substrate, characterized in that is used for a semiconductor package substrate, the substrate, having a rectangular plan shape, and having a through hole extending from the surface of the substrate to the back surface opposite to the surface, The width of the lower end opening of the through hole on the rear surface is equal to or greater than 80% of the width of the upper end opening of the through hole on the front surface.

17. The substrate according to claim 16, wherein The width of the upper end opening of the through-hole on the surface is 20 μm or less.

18. The substrate according to claim 17, wherein A ratio of a processed length of the through hole on the rear surface to a width of a lower end opening of the through hole is 1.0 or greater.

19. A semiconductor package substrate, characterized in that: The semiconductor package substrate comprises a substrate as claimed in any one of claims 1, 8 to 12, and 16 to 18, The through-holes are subjected to through-hole processing.

20. The semiconductor package substrate according to claim 19, wherein A semiconductor element is mounted.

21. The semiconductor package substrate according to claim 19, wherein It has external connection wiring terminals.

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