Interposer and manufacturing method thereof

Abstract

The present invention provides an interposer and a manufacturing method thereof. The interposer comprises: an interposer body formed of a sapphire single crystal and formed in a plate shape having a first surface and a second surface opposite to the first surface; and a body through passage extending from the first surface to the second surface, wherein the interposer body is formed such that the first surface and the second surface are formed parallel to the C-plane of the sapphire single crystal.

Description

Interposer and method of manufacturing the same

[0001] The present invention relates to an interposer used in semiconductor packaging and a method for manufacturing the same.

[0002] With the recent increase in demand for high integration and performance of semiconductor devices, heterogeneous integration technology, which integrates multiple semiconductor chips with different functions within a single package, is emerging as a significant trend. In particular, high-speed data transfer between logic chips and High Bandwidth Memory (HBM) is required in semiconductors for High Performance Computing (HPC), Artificial Intelligence (AI), and data centers; as a packaging technology to realize this, packaging structures utilizing interposers can be widely applied.

[0003] Generally, an interposer is placed between a semiconductor chip and a package substrate and can act as an intermediate layer that mediates electrical connections between multiple semiconductor chips and provides a high-density wiring structure. The interposer can provide the effect of shortening the signal transmission distance between chips and reducing signal delay by forming fine wiring on a silicon substrate or implementing vertical electrical connections using Through Silicon Via (TSV). Conventionally, organic interposers and silicon interposers have been used as the interposer.

[0004] Recently, technology for glass interposers is being developed to replace conventional interposers. Compared to conventional interposers, glass interposers are known to offer advantages such as the ability to perform fine wiring, low dielectric constant and dielectric loss, small deformation and thin thickness, and cost reduction. However, mass manufacturing process technology for glass interposers is still lacking. The TSV formation process for glass interposers is complex, and the increased risk of cracking and breakage during the process can increase overall packaging costs. Furthermore, glass interposers are susceptible to seware formation and thermal fatigue failure. Additionally, since glass interposers have a higher coefficient of thermal expansion compared to silicon substrates, they can cause reliability issues such as silicon substrate cracking, package warpage, bump cracks, or delamination due to stress concentration resulting from the difference in thermal expansion coefficients. Additionally, glass interposers may face difficulties in heat dissipation due to their low thermal conductivity. In addition, when multiple high-heat chips are densely arranged in the glass interposer, localized heat concentration (hot spots) may occur, which can complicate thermal management and heat dissipation design. Therefore, the glass interposer is not yet reliable enough to be applied to actual products.

[0005] The present invention aims to provide an interposer that has a coefficient of thermal expansion relatively similar to that of a silicon substrate or semiconductor chip and reduces crack formation around through-sapphire vias, and a method for manufacturing the same.

[0006] The interposer of the present invention is formed of a sapphire single crystal and comprises an interposer body formed in a plate shape having a first surface and a second surface opposite to the first surface, and a body penetration passage penetrating from the first surface to the second surface, wherein the interposer body is characterized in that the first surface and the second surface are formed parallel to the C-plane of the sapphire single crystal.

[0007] In addition, the above-mentioned main body penetration passage may be formed such that the central axis of the passage penetrates vertically from the first surface to the second surface.

[0008] In addition, the above-mentioned main body penetration passage may be formed such that the central axis of the passage is parallel to the C-axis of the sapphire single crystal.

[0009] In addition, the above-mentioned main body penetration passage may be formed such that the central axis of the passage has an axis-off angle of 0° to 10° with respect to the C-axis of the sapphire single crystal.

[0010] In addition, the above-mentioned main body penetration passage may be formed such that the central axis of the passage has an axis-off angle of 0° to 5° with respect to the C-axis of the sapphire single crystal.

[0011] In addition, the upper diameter of the first surface of the above-mentioned body penetration passage may be formed to be larger than the lower diameter of the second surface.

[0012] In addition, the lower diameter of the above-mentioned body penetration passage may be formed to be smaller than 5 to 10% of the thickness of the interposer body based on the upper diameter.

[0013] In addition, the interposer body is formed with a thickness of 200 to 400 μm, and the body penetration passage can be formed with a diameter of 10 to 200 μm.

[0014] The method for manufacturing an interposer according to the present invention comprises a plate-shaped interposer body formed of a sapphire single crystal and having a first surface and a second surface opposite to the first surface, and a body penetration passage penetrating from the first surface to the second surface, wherein the body penetration passage is formed in the interposer body by irradiating a laser at an angle range of 0° to 10°, which is an axis-off angle with respect to a direction perpendicular to the first surface of the interposer body.

[0015] In addition, the interposer body may have the first and second surfaces formed parallel to the C-plane of the sapphire single crystal and the direction perpendicular to the first and second surfaces parallel to the C-axis of the sapphire single crystal, and the through passage of the body may be formed such that the center axis of the passage has an axis-off angle of 0° to 10° with respect to the C-axis of the sapphire single crystal.

[0016] The interposer of the present invention and the method for manufacturing the same are formed of sapphire and laser-process the main body penetration passage, so the occurrence of cracks during the process of processing the main body penetration passage can be reduced and the processing speed can be increased.

[0017] In addition, the interposer and the method for manufacturing the same according to the present invention form a through-passage through the main body in the c-axis direction of the sapphire, so the occurrence of cracks during the process of machining the through-passage through the main body can be further reduced.

[0018] In addition, the interposer of the present invention and the method for manufacturing the same are formed of sapphire and have a coefficient of thermal expansion similar to that of a semiconductor chip or a silicon substrate, so silicon substrate cracking, package warping, bump cracking, or delamination due to differences in the coefficient of thermal expansion can be reduced.

[0019] In addition, the interposer of the present invention and the method for manufacturing the same are formed of sapphire and have high thermal conductivity, so heat management and heat dissipation can be easily achieved.

[0020] In addition, the interposer of the present invention and the method for manufacturing the same form a passage penetrating the main body in the c-axis direction of sapphire, which has a relatively high thermal conductivity, so heat dissipation can be made easier.

[0021] In addition, the interposer of the present invention and the method for manufacturing the same are formed of sapphire, so they have high mechanical strength and fracture toughness, which reduces seware phenomenon and fatigue fracture, and can prevent damage during the process of forming the main body penetration passage.

[0022] FIG. 1 is a perspective view of an interposer according to one embodiment of the present invention.

[0023] Figure 2 is a vertical cross-sectional view of AA in Figure 1.

[0024] FIG. 3 is a structural diagram of the direction of laser irradiation in an interposer manufacturing method according to one embodiment of the present invention.

[0025] FIG. 4 is an SEM image of the upper part of the main body penetration passage in an example where (a) is an axis-off angle 0°, (b) is an axis-off angle 5°, and (c) is an axis-off angle 10°, and (d) is an SEM image of the lower part of the main body penetration passage where (e) is an axis-off angle 5°, and (f) is an axis-off angle 10°.

[0026] Figure 5 is an enlarged photograph of the main body penetration passage of Figure 4.

[0027] Figure 6 is an SEM image of the upper part of the main body penetration passage in the comparative example, where (a) is an axis-off angle of 15° and (b) is an axis-off angle of 30°, and (c) is an axis-off angle of 15° and (d) is an SEM image of the lower part of the main body penetration passage, where (d) is an axis-off angle of 30°.

[0028] Figure 7 is an enlarged photograph of the main body penetration passage of Figure 6.

[0029] Figure 8 shows an SEM image of the upper part of the main body penetration passage with an axis-off angle of 90° in the comparative example, and an SEM image of the lower part of the main body penetration passage with an axis-off angle of 90°.

[0030] Figure 9 is an enlarged SEM image of the main body penetration passage of Figure 8.

[0031] Figure 10 is an SEM image of the upper surface of the interposer in another comparative example.

[0032] Hereinafter, an interposer according to an embodiment of the present invention and a method for manufacturing the same will be described in more detail.

[0033]

[0034] It should be noted that the technical terms used in this invention are used merely to describe specific embodiments and are not intended to limit the invention. Furthermore, unless specifically defined otherwise in this invention, the technical terms used in this invention should be interpreted in the sense generally understood by those skilled in the art to which this invention pertains, and should not be interpreted in an overly broad or overly narrow sense. Additionally, if a technical term used in this invention is an incorrect technical term that fails to accurately express the concept of the invention, it should be replaced with a technical term that can be correctly understood by those skilled in the art. Moreover, general terms used in this invention should be interpreted according to their prior definitions or the context, and should not be interpreted in an overly narrow sense.

[0035] Furthermore, singular expressions used in the present invention include plural expressions unless the context clearly indicates otherwise. Terms such as "composed of" or "comprising" in the present invention should not be interpreted as necessarily including all of the various components or steps described in the invention; rather, they should be interpreted as meaning that some of the components or steps may be excluded, or that additional components or steps may be included. Additionally, the term "comprising" in the present invention is an open expression and means including the contents disclosed in this specification but not excluding other contents.

[0036] Furthermore, in describing the present invention, detailed descriptions of related prior art are omitted if it is determined that such descriptions could obscure the essence of the invention. Additionally, it should be noted that the attached drawings are intended only to facilitate an understanding of the concept of the present invention and should not be interpreted as limiting the concept of the present invention.

[0037] Singular grammatical terms used herein are intended to include "at least one" or "one or more" unless otherwise indicated herein or clearly contradictory in the context. For example, since "component" means one or more components, perhaps one or more components may be employed or used in the implementation of the embodiments considered and described.

[0038]

[0039] First, an interposer according to one embodiment of the present invention will be described.

[0040] FIG. 1 is a perspective view of an interposer according to one embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of AA of FIG. 1.

[0041] An interposer (100) according to one embodiment of the present invention may include an interposer body (110) and a body penetration passage (120), with reference to FIGS. 1 and 2.

[0042] The interposer (100) may be formed from a sapphire single crystal. Additionally, the interposer (100) may be formed from an alumina (Al2O3) single crystal. Since the interposer (100) is formed from a sapphire single crystal, its relative permittivity (εr) is 10 to 11, which is similar to or lower than that of a silicon interposer, and its dielectric loss is small, with a dielectric loss of 0.0001 to 0.0005 (tanδ), so dielectric loss can be reduced. Additionally, the interposer (100) may have reduced parasitic capacitance and signal loss. Furthermore, the interposer (100) has a thermal conductivity of 35 to 40 W / m·K, which is higher than that of a glass interposer (1 to 2 W / mK), so heat management can be easy. The above interposer (100) has a coefficient of thermal expansion (CTE) of 4 to 5 (ppm / °C), which is small compared to a glass interposer and thus reduces problems caused by thermal expansion.

[0043] In addition, the interposer (100) is formed such that the C-plane of the sapphire single crystal forms the upper and lower planes, thereby allowing for more efficient heat dissipation from the chip. The sapphire single crystal can transfer heat relatively quickly in the C-axis direction.

[0044] The interposer (100) may be formed into a plate having a predetermined thickness and area. The interposer (100) may be formed with an appropriate thickness and area depending on the structure and area of ​​the package to which it is applied. The interposer (100) may be formed with a thickness of 200 to 800 μm. The interposer (100) may preferably be formed with a thickness of 250 to 500 μm. The interposer (100) may include a body penetration passage (120) that penetrates from the upper surface to the lower surface of the interposer body (110) in the interposer body (110).

[0045] The above interposer (100) can be used in 2.5D packages, HBM stacking, and high-density semiconductor packages.

[0046]

[0047] The above interposer body (110) may be formed into a plate having a first surface (111) and a second surface (112) and having a predetermined thickness and area. The first surface (111) and the second surface (112) may be opposite surfaces facing each other with respect to the interposer body (110). That is, the first surface (111) may form an upper surface, and the second surface (112) may form a lower surface. The first surface (111) and the second surface (112) may be surfaces parallel to each other.

[0048] The interposer body (110) can determine the overall shape of the interposer (100). The interposer body (110) can be formed with an appropriate area depending on the structure and area of ​​the package to which it is applied. In addition, the interposer body (110) can be formed with a predetermined thickness. The interposer body (110) can be formed with a thickness of 200 to 800 μm. The interposer body (110) can preferably be formed with a thickness of 200 to 400 μm. If the thickness of the interposer body (110) is too thick, the tapering of the body penetration passage (120) may be increased.

[0049] The interposer body (110) may be formed from a sapphire single crystal. Additionally, the interposer body (110) may be formed such that the first plane (111) and the second plane (112) are parallel to the C-plane of the sapphire single crystal. The interposer body (110) may be formed such that the first plane (111) and the second plane (112) are parallel to the C-plane of the sapphire single crystal. The interposer body (110) may be formed such that the first plane (111) and the second plane (112) are the C-plane of the sapphire single crystal. The interposer body (110) may be formed such that the first plane (111) and the second plane (112) are perpendicular to the C-axis of the sapphire single crystal. Here, the C-axis of the sapphire single crystal may be an axis perpendicular to the C-plane of the sapphire single crystal.

[0050] The above sapphire single crystal may be formed as a trigonal crystal having a corundum structure. The sapphire crystal may include a C-plane (0 0 0 1), an R-plane (1 -1 0 2), an A-plane (1 1 -2 0), and an M-plane (1 0 -1 0). Additionally, the sapphire crystal may include a C-axis, an a1-axis, an a2-axis, and an a3-axis. The C-axis may be an axis perpendicular to the C-plane. The a1-axis, a2-axis, and a3-axis may be axes formed at 120-degree intervals in a plane parallel to the C-plane. The C-axis may be an axis perpendicular to the a1-axis, a2-axis, and a3-axis.

[0051]

[0052] The above body penetration passage (120) may be formed as a passage penetrating from the first surface (111) to the second surface (112) of the interposer body (110). The above body penetration passage (120) may be formed to penetrate vertically from the first surface (111) to the second surface (112). The above body penetration passage (120) may be formed such that the passage center axis (120a) is parallel to the C-axis. Additionally, the above body penetration passage (120) may be formed as a passage where the passage center axis (120a) is perpendicular to the C-plane. The passage center axis (120a) may refer to a line formed along the center of the body penetration passage (120) in the direction in which the body penetration passage (120) extends. The above body penetration passage (120) may be formed by irradiating a laser.

[0053] The above-mentioned body through-passage (120) may be a through-sapphire via. The above-mentioned body through-passage (120) may be a passage that functions in the same way as a through-silicon via (TSV) of a silicon substrate or a through-glass via of a glass substrate. Accordingly, the above-mentioned body through-passage (120) may be filled with copper during the packaging process.

[0054] The above-mentioned main body penetration passage (120) can be formed such that the central axis (120a) of the passage is C-axis and the axis off angle (120b) is 0° to 10°. The above-mentioned main body penetration passage (120) can preferably be formed such that the axis off angle (120b) is 0° to 5°. The above-mentioned main body penetration passage (120) can be formed such that the axis off angle (120b) is 10° or less so that cracks extending around the inner surface of the main body penetration passage (120) may not occur. The above-mentioned main body penetration passage (120) can be formed such that the axis off angle (120b) is 5° or less so that cracks extending around the inner surface of the main body penetration passage (120) may not occur further. If the axis off angle (120b) of the above-mentioned main body penetration passage (120) becomes large, cracks may occur around the main body penetration passage (120) during the formation process of the main body penetration passage (120). Here, the axis off angle (120b) refers to the angle between the angle at which the laser is irradiated and the C-axis of the interposer body (110). Therefore, when the axis off angle (120b) is 5°, it means that the laser is irradiated in a direction tilted 5° with respect to the C-axis.

[0055] The above body penetration passage (120) can be formed with a required diameter depending on the package used. The above body penetration passage (120) can be formed with a diameter of 10 to 200 μm. Additionally, the above body penetration passage (120) can be formed with a diameter of 50 to 150 μm. Here, the diameter of the above body penetration passage (120) may refer to the diameter of a circle perpendicular to the central axis (120a) of the passage.

[0056] Additionally, the above-mentioned body penetration passages (120) may be formed with a required pitch depending on the package in which multiple passages are used. For example, the above-mentioned body penetration passages (120) may be formed to have a pitch of 100 to 150 μm.

[0057] The above body penetration passage (120) can be formed by laser processing irradiated onto the first surface (111). The above body penetration passage (120) may have a diameter deviation between the upper diameter of the first surface (111) and the lower diameter of the second surface (112). The above body penetration passage (120) may be formed such that the upper diameter is larger than the lower diameter. The diameter deviation refers to the difference between the upper diameter and the lower diameter, and the lower diameter may be relatively smaller compared to the upper diameter. The diameter deviation of the above body penetration passage (120) may increase as the thickness of the interposer body (110) increases. The above body penetration passage (120) may be formed such that the lower diameter is smaller than the upper diameter, by 5 to 10% of the thickness of the interposer body (110). The above body penetration passage (120) may preferably be formed to have a diameter deviation of 5 to 8%. For example, the diameter deviation of the above body penetration passage (120) may be 5 to 8 µm when the thickness of the interposer body (110) is 100 µm. That is, when the upper diameter of the above body penetration passage (120) is 100 µm, the lower diameter may be 90 to 95 µm.

[0058]

[0059] The following describes a method for manufacturing an interposer according to one embodiment of the present invention.

[0060] FIG. 3 is a structural diagram of the direction of laser irradiation in an interposer manufacturing method according to one embodiment of the present invention.

[0061] A method for manufacturing an interposer according to one embodiment of the present invention can form a through hole in the main body by irradiating a laser from the first surface (111) to the second surface (112) of the interposer main body (110), as shown in FIG. 3.

[0062] The above method for manufacturing an interposer may use a laser irradiation device (10) to irradiate a laser (10a) in a direction perpendicular to the first surface (111) of the interposer body (110). Here, the first surface (111) of the interposer body (110) is the C-plane of the sapphire single crystal forming the interposer body (110), and the direction perpendicular to the first surface (111) may be the C-axis of the sapphire single crystal. The laser irradiation device may perform laser processing under conditions where Power@100KHz is 16W, Burst Pulse Pitch is 10nsec, line is 3, scan Speed ​​is 0.2m / sec, and Delay time is 0.5sec.

[0063] Additionally, the above interposer manufacturing method may irradiate a laser (10a) in an angle range of 0° to 10°, which is an axis-off angle (120b), in a direction perpendicular to the first surface (111) of the interposer body (110). Accordingly, the interposer (100) may have a body penetration passage (120) formed such that the passage center axis (120a) of the body penetration passage (120) forms an angle of 0° to 10°, which is an axis-off angle (120b), with respect to the direction perpendicular to the first surface (111).

[0064]

[0065] The following describes specific embodiments of the present invention.

[0066] The interposer of a specific embodiment of the present invention was manufactured with the following configuration and conditions.

[0067] - Interposer material: Sapphire single crystal

[0068] - Interposer thickness: 300㎛

[0069] - Diameter of the main body penetration passage: 100㎛

[0070] - Axis Off Angle: 0°, 5°, 10°

[0071] - Machining of through passages in the main body: Machining using a pico laser

[0072] Here, the axis off angle refers to the angle between the angle at which the laser is irradiated and the C-axis of the interposer body. Therefore, when the axis off angle is 5°, it means that the laser is irradiated in a direction tilted 5° with respect to the C-axis.

[0073] A comparative example for the embodiment of the present invention was manufactured under the following conditions. The comparative example was identical to the embodiment except for the axis off-angle. The comparative example is intended to evaluate the effect of the axis off-angle in comparison to the embodiment. Therefore, the comparative example is not a comparative example for the embodiment with respect to other configurations.

[0074] - Axis Off Angle: 15°, 30°, 90°

[0075] Here, when the axis off angle is 90°, it means that the irradiation is performed in a direction forming 90° with the C-axis. Accordingly, the interposer body of the comparative example with an axis off angle of 90° is formed such that the first surface and the second surface are perpendicular to the C-axis of the sapphire single crystal, and the body penetration passage is formed in a direction perpendicular to the first surface. In particular, the interposer body of the comparative example has the first surface and the second surface formed parallel to the A-plane of the sapphire single crystal.

[0076] In addition, as another comparative example, through-glass vias (TGVs) were formed on a glass substrate that is currently under development.

[0077]

[0078] The evaluation results for the examples, comparative examples, and other examples are described below.

[0079] FIG. 4 is an SEM image of the upper part of a body penetration passage in an example where (a) is an axis-off angle 0°, (b) is an axis-off angle 5°, and (c) is an axis-off angle 10°, and (d) is an SEM image of the lower part of a body penetration passage where (e) is an axis-off angle 0°, and (f) is an axis-off angle 10°. FIG. 5 is an enlarged image of the body penetration passage of FIG. 4.

[0080] Figure 6 is an SEM image of the upper part of the body penetration passage in the comparative example, where (a) is an axis-off angle of 15° and (b) is an axis-off angle of 30°, and (c) is an SEM image of the lower part of the body penetration passage, where (d) is an axis-off angle of 15° and (d) is an axis-off angle of 30°. Figure 7 is an enlarged image of the body penetration passage of Figure 6.

[0081] Figure 8 is an SEM image of the upper part of the body penetration passage with an axis-off angle of 90° in the comparative example, and an SEM image of the lower part of the body penetration passage with an axis-off angle of 90°. Figure 9 is an enlarged SEM image of the body penetration passage of Figure 8.

[0082] Figure 10 is an SEM image of the upper surface of the interposer in another comparative example.

[0083] As shown in FIGS. 4 and 5, it can be confirmed that the main body penetration passage of the interposer of the embodiments is formed in an almost circular shape. Furthermore, it can be confirmed that no fine cracks occur in the upper part of the main body penetration passage of the interposer of the embodiments. Additionally, it can be confirmed that no fragments are detached from the upper entrance of the main body penetration passage of the embodiments. Furthermore, it can be confirmed that no cracks occur in the lower part of the main body penetration passage of the embodiments. It can be confirmed that the interposer of the embodiments enables the processing of fine main body penetration passages with a small diameter so that no cracks are formed around the hole of the main body penetration passage. Since no cracks occur around the hole of the main body penetration passage in the direction of the passage center axis of the main body penetration passage, it can be confirmed that no cracks occur in the direction perpendicular to the passage center axis at the same time. Therefore, since the interposer of the embodiments does not generate cracks that cause seware—that is, cracks that form in the direction perpendicular to the passage center axis of the main body penetration passage—the seware phenomenon can also be prevented. Meanwhile, in the main body penetration passages of the embodiments, a foreign substance shape formed radially at the bottom can be observed. The foreign substance shape is unrelated to cracks and is confirmed to be formed as sapphire particles molten by a laser are ejected during the process of forming the main body penetration passage using a laser.

[0084] Since atoms in a sapphire single crystal are arranged isotropically in the C-plane, it is determined that maintaining the circular shape is easy when the penetration passage through the main body of the interposer is machined into a circular shape. Furthermore, since the fracture toughness of a sapphire single crystal is highest in the C-plane, it is determined that cracks do not occur relatively in the interposer of the example when the axis-off angle is 0°, 5°, and 10°. In particular, the sapphire single crystal has the densest atomic arrangement in the C-plane and strong interatomic bonding forces, resulting in high mechanical strength. Additionally, regarding the thermal energy of the laser irradiated through the C-plane, thermal stress is efficiently dispersed in the sapphire single crystal, and thermal expansion, thermal stress, and fracture toughness are uniformly distributed rotationally symmetrically around the C-axis, preventing cracks from occurring.

[0085] As shown in FIGS. 6 and 7, it can be observed that the main body penetration passage of the interposer in the comparative example does not maintain a circular shape. Since the atoms of a sapphire single crystal become anisotropically arranged as they tilt toward the C-plane, it is determined that it is difficult to maintain a circular shape when processing the main body penetration passage of the interposer into a circular shape. Furthermore, in the interposer in the comparative example, fine cracks and debris can be observed falling off from the upper part of the main body penetration passage. Additionally, in the main body penetration passages of the comparative examples, foreign matter formed radially on the lower part can be observed. In the interposer in the comparative example, cracks are observed to be larger when the axis off angle is 30° compared to when the axis off angle is 15°.

[0086] In addition, as shown in FIGS. 8 and 9, in the interposer of the comparative example, when the axis-off angle is 90°, it can be observed that a wide crack extending in an irregular direction is formed at the upper and lower parts of the body penetration passage. In the interposer of the comparative example, the axis-off angle is 90°, and since the body penetration passage is formed in a direction perpendicular to the A-plane of the sapphire single crystal, it becomes difficult to maintain the shape of the hole. Furthermore, since the atomic arrangement of the A-plane of the sapphire single crystal is relatively loose and exhibits strong anisotropy, the possibility of the hole shape being deformed increases when the body penetration passage is formed as a circular hole. Moreover, since the A-plane of the sapphire single crystal is the lateral direction of the hexagonal crystal structure, the atomic arrangement is not uniform; consequently, the material removal rate and energy absorption vary depending on the crystal structure direction, resulting in different processing speeds and making it difficult to maintain the circular shape of the hole. Furthermore, the A-plane of a sapphire single crystal has relatively weak bonding forces due to the relatively large interatomic distances, and since heat transfer and thermal expansion vary by direction, it is prone to cracking as stress concentrates when localized thermal shock is applied by a laser.

[0087] Meanwhile, as shown in FIG. 10, it can be observed that cracks are formed around the through-glass vias in an interposer formed on a glass substrate. Since heat transfer is very difficult in an interposer formed on a glass substrate, it is believed that microcracks occur due to thermal stress when heat accumulates during laser processing. In particular, it is confirmed that in a glass substrate interposer, chipping and cracking occur at the edges of the through-glass vias and propagate into the area between the through-glass vias.

[0088] In contrast, since the interposer formed from a sapphire single crystal has high thermal conductivity, thermal stress is significantly reduced when processing the penetrating passage of the main body with a laser, and the possibility of thermal cracking is reduced. In particular, since the sapphire single crystal has an isotropic atomic arrangement in the C-plane, heat transfer in the direction occurs isotropically, so the possibility of cracking due to thermal stress is reduced.

[0089]

[0090] The present invention has been described in detail so far, focusing on preferred embodiments. These embodiments are merely illustrative and are not intended to limit the invention; they should be considered in an illustrative rather than a limiting sense. The true technical scope of protection of the present invention should be determined by the technical spirit of the appended claims, rather than by the foregoing description.

Claims

1. An interposer body formed in a plate shape having a first surface and a second surface opposite to the first surface, formed of a sapphire single crystal, and It includes a main body penetration passage penetrating from the first surface to the second surface, and The interposer body is characterized in that the first surface and the second surface are formed parallel to the C-plane of the sapphire single crystal.

2. In Paragraph 1, An interposer characterized in that the above-described main body penetration passage is formed such that the central axis of the passage penetrates vertically from the first surface to the second surface.

3. In Paragraph 1, An interposer characterized in that the above-described main body penetration passage is formed such that the central axis of the passage is parallel to the C-axis of the sapphire single crystal.

4. In Paragraph 1, An interposer characterized in that the above-described main body penetration passage is formed such that the central axis of the passage has an axis-off angle of 0° to 10° with respect to the C-axis of the sapphire single crystal.

5. In Paragraph 4, An interposer characterized in that the above-described main body penetration passage is formed such that the central axis of the passage has an axis-off angle of 0° to 5° with respect to the C-axis of the sapphire single crystal.

6. In Paragraph 1, An interposer characterized in that the above-described main body penetration passage is formed such that the upper diameter of the first surface is larger than the lower diameter of the second surface.

7. In Paragraph 6, An interposer characterized in that the above-mentioned main body penetration passage is formed such that the lower diameter is smaller than the upper diameter, at 5 to 10% of the thickness of the interposer main body.

8. In Paragraph 1, The above interposer body is formed with a thickness of 200 to 400 μm, and An interposer characterized in that the above-mentioned main body penetration passage is formed with a diameter of 10 to 200 μm.

9. A method for manufacturing an interposer comprising a plate-shaped interposer body formed of a sapphire single crystal and having a first surface and a second surface opposite to the first surface, and a body penetration passage penetrating from the first surface to the second surface. A method for manufacturing an interposer characterized by forming a penetrating passage in the interposer body by irradiating a laser at an angle range of 0° to 10°, which is an axis-off angle, with respect to a direction perpendicular to the first surface of the interposer body.

10. In Paragraph 9, The above interposer body has the first and second surfaces formed parallel to the C-plane of the sapphire single crystal, and the direction perpendicular to the first and second surfaces is parallel to the C-axis of the sapphire single crystal, and A method for manufacturing an interposer, characterized in that the above-described main body penetration passage is formed such that the central axis of the passage has an axis-off angle of 0° to 10° with respect to the C-axis of the sapphire single crystal.

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