Method for manufacturing low temperature co-fired ceramic substrate, low temperature co-fired ceramic substrate, method for manufacturing high temperature co-fired ceramic substrate, high temperature co-fired ceramic substrate, space transformer substrate, and probe card

Abstract

This method for manufacturing a low temperature co-fired ceramic substrate comprises a firing step S3 and a pore part formation step S4. The pore part formation step S4 includes: a first recess part formation step S41 for forming a first recess part 9 by irradiating a first main surface Sa of a low temperature co-fired ceramic substrate 6 with a laser beam L; and a machining step S43 for forming a pore part 11 by performing machining from the first recess part 9 toward a second main surface Sb of the low temperature co-fired ceramic substrate 6.

Description

Method for manufacturing low-temperature co-firing ceramic substrates, low-temperature co-firing ceramic substrates, method for manufacturing high-temperature co-firing ceramic substrates, high-temperature co-firing ceramic substrates, space transformer substrates, and probe cards 【0001】 The present invention relates to a method for manufacturing a low-temperature co-firing ceramic substrate, a low-temperature co-firing ceramic substrate, a method for manufacturing a high-temperature co-firing ceramic substrate, a high-temperature co-firing ceramic substrate, a space transformer substrate, and a probe card. 【0002】 Probe cards are used to test the electrical characteristics of chips on semiconductor wafers. Known probe cards include a probe substrate, a main substrate connected to the probe substrate, and a support member connecting the probe substrate and the main substrate (see, for example, paragraph 0025 of Patent Document 1). 【0003】 The probe substrate is supported on the main substrate via a support member. The probe substrate comprises a probe and a space transformer substrate. The probe is a component that contacts the electrodes of a chip on a semiconductor wafer. The space transformer substrate is a wiring substrate that has the function of converting the wiring pitch on one main surface side to the other main surface side. The space transformer substrate is made of, for example, a substrate of low-temperature co-fired ceramics (LTCC). Electrode pads are formed on the space transformer substrate, and the probe is bonded to these electrode pads. 【0004】 The probe card makes contact with the chip on the semiconductor wafer being tested at the tip of the probe, and performs chip testing by communicating electrical signals with the tester device via the space transformer substrate and main substrate. 【0005】 Japanese Patent Publication No. 2023-97314 【0006】In a probe card having the above configuration, one way to support the space transformer substrate with a support member is to form a through-hole in the space transformer substrate and insert the support member through this through-hole, thereby connecting the space transformer substrate and the main substrate. 【0007】 For space transformer substrates, it is preferable to use low-temperature co-fired ceramic substrates that can effectively form electrical wiring. However, when through holes are formed in low-temperature co-fired ceramic substrates using rotary machining tools, chipping may occur in the through holes. If chipping occurs in the through holes, it can lead to damage to the space transformer substrate and a decrease in quality. This problem can occur not only with low-temperature co-fired ceramic substrates but also when forming through holes in high-temperature co-fired ceramics (HTCC) substrates. 【0008】 The present invention has been made in view of the above circumstances, and aims to suppress the occurrence of chipping when forming holes in a low-temperature co-fired ceramic substrate or a high-temperature co-fired ceramic substrate used as a space transformer substrate. 【0009】 (1) The present invention is for solving the above problems and is a method for manufacturing a low-temperature co-fired ceramic substrate, comprising: a firing step of firing the low-temperature co-fired ceramic substrate; and a hole-forming step of forming holes in the low-temperature co-fired ceramic substrate after firing, wherein the low-temperature co-fired ceramic substrate has a first main surface and a second main surface located on the opposite side of the first main surface, and the hole-forming step is characterized by comprising: a first recess-forming step of forming a first recess by irradiating the first main surface of the low-temperature co-fired ceramic substrate with laser light; and a machining step of forming holes by machining from the first recess toward the second main surface of the low-temperature co-fired ceramic substrate. 【0010】Low-temperature co-fired ceramic substrates are laminates obtained by stacking and firing multiple green sheets. Therefore, the cross-section of a low-temperature co-fired ceramic substrate in the stacking direction tends to be uneven. More specifically, the interface between each green sheet after firing will have a cross-section that remains uneven even after firing. Therefore, according to the present invention, by irradiating the first main surface of the low-temperature co-fired ceramic substrate with laser light in the first recess formation step, it becomes possible to melt a portion of the first main surface and form a first recess. Since the first recess is formed by melting the first main surface, it becomes possible to modify the aforementioned uneven cross-sectional state to a smooth state. Therefore, even when forming holes from these first recesses in subsequent machining processes, it becomes easier to avoid chipping caused by the uneven cross-sectional state. 【0011】 (2) The present invention is for solving the above problems and is a method for manufacturing a low-temperature co-fired ceramic substrate, comprising: a firing step of firing the low-temperature co-fired ceramic substrate; and a hole-forming step of forming holes in the low-temperature co-fired ceramic substrate after firing, wherein the low-temperature co-fired ceramic substrate has a first main surface and a second main surface located on the opposite side of the first main surface, and the hole-forming step is characterized by comprising: a first recess-forming step of forming a first recess by etching the first main surface of the low-temperature co-fired ceramic substrate; and a machining step of forming holes by machining from the first recess toward the second main surface of the low-temperature co-fired ceramic substrate. 【0012】Low-temperature co-fired ceramic substrates are laminates obtained by stacking and firing multiple green sheets. Therefore, the cross-section of a low-temperature co-fired ceramic substrate in the stacking direction tends to be uneven. More specifically, the interface between each green sheet after firing will have a cross-section that remains uneven even after firing. Therefore, according to the present invention, by applying an etching treatment to the first main surface of the low-temperature co-fired ceramic substrate in the first recess formation step, it becomes possible to form a first recess on a part of the first main surface. Since the first recess is formed by etching the first main surface, it becomes possible to smooth the aforementioned unevenness of the cross-section. Therefore, even when forming holes from these first recesses in subsequent machining processes, it becomes easier to avoid chipping caused by the unevenness of the cross-section. 【0013】 (3) The method for manufacturing a low-temperature co-fired ceramic substrate as described in (1) above, further comprising a second recess formation step, which is performed after the first recess formation step and before the machining step, in which a second recess is formed on the second main surface of the low-temperature co-fired ceramic substrate at a position opposite to the first recess, wherein laser light may be irradiated onto the second main surface in the second recess formation step. 【0014】 With this configuration, in the second recess formation process, a laser beam is irradiated onto the second main surface of the low-temperature co-fired ceramic substrate, melting a portion of the second main surface to form the second recess. Since the second recess is formed by melting the second main surface, chipping is easily avoided, similar to the first recess. Therefore, if a hole is made to penetrate this second recess during the machining process, the occurrence of chipping on the second recess side of the hole can be suppressed. 【0015】 (4) The method for manufacturing a low-temperature co-fired ceramic substrate as described in (2) above, comprising a second recess formation step in which a second recess is formed on the second main surface of the low-temperature co-fired ceramic substrate at a position opposite to the first recess, wherein the second recess may be formed in the second recess formation step by etching the second main surface. 【0016】In this configuration, the second recess is formed by etching the second main surface of the low-temperature co-fired ceramic substrate during the second recess formation process. Since the second recess is formed by etching the second main surface, chipping is easily avoided, similar to the first recess. Therefore, if a hole is made to penetrate this second recess during the machining process, the occurrence of chipping on the second recess side of the hole can be suppressed. 【0017】 (5) In the method for manufacturing a low-temperature co-firing ceramic substrate described in any of (1) to (4) above, the depth of the first recess may be shallower than the depth of the hole. 【0018】 With this configuration, the energy cost of irradiation with laser light can be reduced, or the etching process can be performed efficiently. On the other hand, there is a risk that cutting by the machine during the machining process may cause microcracks to form on the surface of the side of the hole, reducing the mechanical strength of the low-temperature co-fired ceramic substrate. Therefore, in a cross-sectional view of the low-temperature co-fired ceramic substrate, the value obtained by dividing the depth (length) of the side of the hole by the depth (length) of the first recess is preferably 10 to 1000, more preferably 10 to 800. 【0019】 (6) In the method for manufacturing a low-temperature co-firing ceramic substrate described in any of (1) to (5) above, the holes do not have to penetrate to the second main surface. That is, even if the holes do not penetrate to the second main surface in a single machining step as described above, it is possible to penetrate to the second main surface by an additional machining step. 【0020】 (7) In the method for manufacturing a low-temperature co-firing ceramic substrate described in any of (1) to (5) above, the holes may penetrate to the second main surface. 【0021】 (8) In the method for manufacturing a low-temperature co-firing ceramic substrate described in (3) or (4) above, the holes may penetrate to the second recess. 【0022】(9) In the method for manufacturing a low-temperature co-firing ceramic substrate as described in any of (1) to (8) above, the method includes a preparation step of preparing a green sheet before the firing step, and the depth of the first recess may be less than the thickness of one of the green sheets. 【0023】 With this configuration, by forming the first recess within the thickness range of the green sheet, the energy cost of irradiation with laser light can be reduced, and the etching process can be performed efficiently. 【0024】 (10) In the method for manufacturing a low-temperature co-fired ceramic substrate according to any of (1) to (9) above, the first recess may have a side surface and a bottom surface formed between the side surface and the hole. 【0025】 (11) In the method for manufacturing a low-temperature co-firing ceramic substrate as described in (10) above, the side surface of the first recess is formed in a circular shape in plan view, and in the machining step, the hole may be formed by a machining tool having a diameter smaller than the diameter of the side surface. 【0026】 With this configuration, it becomes possible to reliably form a hole within the range of the first recess. 【0027】 (12) The present invention is for solving the above problems and is a method for manufacturing a high-temperature co-fired ceramic substrate, comprising: a firing step of firing the high-temperature co-fired ceramic substrate; and a hole forming step of forming a hole in the high-temperature co-fired ceramic substrate after firing, wherein the high-temperature co-fired ceramic substrate has a first main surface and a second main surface located on the opposite side of the first main surface, and the hole forming step is characterized by comprising: a first recess forming step of forming a first recess by irradiating the first main surface of the high-temperature co-fired ceramic substrate with laser light; and a machining step of forming the hole by machining from the first recess toward the second main surface of the high-temperature co-fired ceramic substrate. 【0028】High-temperature co-fired ceramic substrates are laminates obtained by stacking and firing multiple green sheets. Therefore, the cross-section of a high-temperature co-fired ceramic substrate in the stacking direction tends to be uneven. More specifically, the interface between each green sheet after firing will have a cross-section that remains uneven even after firing. According to the present invention, by irradiating the first main surface of the high-temperature co-fired ceramic substrate with laser light in the first recess formation step, it becomes possible to melt a portion of the first main surface and form a first recess. Since the first recess is formed by melting the first main surface, it becomes possible to modify the aforementioned uneven cross-sectional state to a smooth state. Therefore, even when forming holes from these first recesses in subsequent machining processes, it becomes easier to avoid chipping caused by the uneven cross-sectional state. 【0029】 (13) The present invention is for solving the above problems and is a method for manufacturing a high-temperature co-fired ceramic substrate, comprising: a firing step of firing the high-temperature co-fired ceramic substrate; and a hole forming step of forming holes in the high-temperature co-fired ceramic substrate after firing, wherein the high-temperature co-fired ceramic substrate has a first main surface and a second main surface located on the opposite side of the first main surface, and the hole forming step is characterized by comprising: a first recess forming step of forming a first recess by etching the first main surface of the high-temperature co-fired ceramic substrate; and a machining step of forming holes by machining from the first recess toward the second main surface of the high-temperature co-fired ceramic substrate. 【0030】A high-temperature co-fired ceramic substrate is a laminate obtained by stacking and firing a plurality of green sheets. Therefore, the cross-section in the stacking direction of the high-temperature co-fired ceramic substrate tends to be uneven. More specifically, the interface of each green sheet after firing will have a cross-section that is not smoothed by firing. Thus, according to the present invention, by performing an etching process on the first main surface of the high-temperature co-fired ceramic substrate in the first recess forming step, it becomes possible to form a first recess in a part of the first main surface. In this way, since the first recess is formed by performing an etching process on the first main surface, it becomes possible to make the uneven state of the aforementioned cross-section smooth. For this reason, even if a hole is formed from this first recess in a subsequent machining process, it becomes easier to avoid the occurrence of chipping due to the uneven state of the cross-section. 【0031】 (14) In the method for manufacturing a high-temperature co-fired ceramic substrate according to the above (12), after the first recess forming step and before the machining step, a second recess forming step for forming a second recess at a position on the second main surface of the high-temperature co-fired ceramic substrate facing the first recess is provided. In the second recess forming step, laser light may be irradiated onto the second main surface. 【0032】 According to such a configuration, by irradiating laser light onto the second main surface of the high-temperature co-fired ceramic substrate in the second recess forming step, a part of the second main surface is melted to form a second recess. In this way, since the second recess is formed by melting the second main surface, it becomes easier to avoid the occurrence of chipping, similar to the first recess. Therefore, in the machining step, if a hole is made to penetrate through this second recess, the occurrence of chipping on the second recess side of the hole can be suppressed. 【0033】 (15) In the method for manufacturing a high-temperature co-fired ceramic substrate according to the above (13), a second recess forming step for forming a second recess at a position on the second main surface of the high-temperature co-fired ceramic substrate facing the first recess is provided. In the second recess forming step, the second recess may be formed by performing an etching process on the second main surface. 【0034】According to such a configuration, in the second recess forming step, an etching process is performed on the second main surface of the co-fired ceramic substrate at high temperature to form a second recess. Thus, since the second recess is formed by performing an etching process on the second main surface, it is easy to avoid the occurrence of chipping as in the case of the first recess. Therefore, in the machining step, if a hole is made to penetrate the second recess, the occurrence of chipping on the second recess side of the hole can be suppressed. 【0035】 (16) In the method for manufacturing a co-fired ceramic substrate according to any one of (12) to (15) above, the depth of the first recess may be shallower than the depth of the hole. 【0036】 According to such a configuration, the irradiation energy cost by laser light can be reduced, or the etching process can be efficiently performed. On the other hand, in the cutting by a machine in the machining step, there is a risk of generating microcracks on the surface of the side surface of the hole and reducing the mechanical strength of the co-fired ceramic substrate. Therefore, in a cross-sectional view of the co-fired ceramic substrate, the value obtained by dividing the depth (length) of the side surface of the hole by the depth (length) of the first recess is preferably 10 to 1000, more preferably 10 to 800. 【0037】 (17) In the method for manufacturing a co-fired ceramic substrate according to any one of (12) to (16) above, the hole may not penetrate to the second main surface. That is, even if the hole is not formed to penetrate to the second main surface in a single machining step as described above, it is possible to penetrate the hole to the second main surface by an additional machining step. 【0038】 (18) In the method for manufacturing a co-fired ceramic substrate according to any one of (12) to (16) above, the hole may penetrate to the second main surface. 【0039】 (19) In the method for manufacturing a co-fired ceramic substrate according to (14) or (15) above, the hole may penetrate to the second recess. 【0040】(20) In the method for manufacturing a high-temperature co-firing ceramic substrate as described in any of (12) to (19) above, a preparation step of preparing a green sheet is provided before the firing step, and the depth of the first recess may be less than the thickness of one of the green sheets. 【0041】 With this configuration, by forming the first recess within the thickness range of the green sheet, the energy cost of irradiation with laser light can be reduced, and the etching process can be performed efficiently. 【0042】 (21) In the method for manufacturing a high-temperature co-firing ceramic substrate described in any of (12) to (20) above, the first recess may have a side surface and a bottom surface formed between the side surface and the hole. 【0043】 (22) In the method for manufacturing a high-temperature co-firing ceramic substrate as described in (21) above, the side surface of the first recess is formed in a circular shape in plan view, and in the machining step, the hole may be formed by a machining tool having a diameter smaller than the diameter of the side surface. 【0044】 With this configuration, it becomes possible to reliably form a hole within the range of the first recess. 【0045】 (23) The present invention is for solving the above problems and is a low-temperature co-fired ceramic substrate having a first main surface and a second main surface located on the opposite side of the first main surface, the substrate having a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, the first recess having a side surface and a bottom surface formed between the side surface and the hole, the first recess being located on the first main surface side, the hole having a side surface and being located on the second main surface side, the side surface of the first recess being a forging surface, at least a part of the bottom surface of the first recess being a forging surface, and in plan view, the hole is smaller than the first recess. 【0046】With this configuration, by forming the side surface of the first recess with a forged surface and forming at least a portion of the bottom surface of the first recess with a forged surface, the mechanical strength of the first recess, which is susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the low-temperature co-fired ceramic substrate. 【0047】 (24) The present invention is for solving the above problems and is a low-temperature co-fired ceramic substrate having a first main surface and a second main surface located on the opposite side of the first main surface, having a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, wherein the first recess has a side surface and a bottom surface formed between the side surface and the hole, the first recess is located toward the first main surface, the hole has a side surface and is located toward the second main surface, the side surface of the first recess is an etched surface, at least a part of the bottom surface of the first recess is an etched surface, and in plan view, the hole is smaller than the first recess. 【0048】 With this configuration, by forming the side surface of the first recess with an etched surface and forming at least a portion of the bottom surface of the first recess with an etched surface, the mechanical strength of the first recess, which is susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the low-temperature co-fired ceramic substrate. 【0049】 (25) In the low-temperature co-fired ceramic substrate described in (23) above, a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess may have a forging surface. 【0050】 (26) In the low-temperature co-fired ceramic substrate described in (24) above, a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess may have an etched surface. 【0051】(27) In the low-temperature co-fired ceramic substrate described in any of (22) to (27) above, it is preferable that the side surface of the first recess has a plurality of voids, the side surface of the hole has a plurality of voids, and the number of voids per unit area on the side surface of the first recess is less than the number of voids per unit area on the side surface of the hole. 【0052】 With this configuration, the mechanical strength of the first recess, which is close to the first main surface and the second main surface, which are susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the low-temperature co-fired ceramic substrate. 【0053】 (28) In the low-temperature co-fired ceramic substrate described in any of (22) to (27) above, the depth of the first recess is 10 μm to 100 μm, and the thickness of the low-temperature co-fired ceramic substrate may be 1 mm to 10 mm. 【0054】 (29) In the low-temperature co-fired ceramic substrate described in any of (22) to (28) above, the side surface of the hole may be a machined surface. 【0055】 (30) In the low-temperature co-fired ceramic substrate described in any of (22) to (29) above, the side surface of the first recess is configured to be circular in plan view, the side surface of the hole is configured to be circular in plan view, and the difference between the diameter of the first recess and the diameter of the hole may be 0.01 mm to 1 mm. 【0056】 (31) In the low-temperature co-fired ceramic substrate described in any of (22) to (30) above, the low-temperature co-fired ceramic substrate has a circuit formation region, and the first recess and the hole may be located outside the circuit formation region. 【0057】(32) The present invention is for solving the above problems and is a high-temperature co-fired ceramic substrate having a first main surface and a second main surface located on the opposite side of the first main surface, the substrate having a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, the first recess having a side surface and a bottom surface formed between the side surface and the hole, the first recess being located on the first main surface side, the hole having a side surface and being located on the second main surface side, the side surface of the first recess being a forging surface, at least a part of the bottom surface of the first recess being a forging surface, and in plan view, the hole is smaller than the first recess. 【0058】 With this configuration, by forming the side surface of the first recess with a forged surface and forming at least a portion of the bottom surface of the first recess with a forged surface, the mechanical strength of the first recess, which is susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the high-temperature co-fired ceramic substrate. 【0059】 (33) The present invention is for solving the above problems and is a high-temperature co-fired ceramic substrate having a first main surface and a second main surface located on the opposite side of the first main surface, the substrate having a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, the first recess having a side surface and a bottom surface formed between the side surface and the hole, the first recess being located toward the first main surface, the hole having a side surface and being located toward the second main surface, the side surface of the first recess being an etched surface, and at least a part of the bottom surface of the first recess being an etched surface, and in plan view, the hole is smaller than the first recess. 【0060】 With this configuration, by forming the side surface of the first recess with an etched surface and forming at least a portion of the bottom surface of the first recess with an etched surface, the mechanical strength of the first recess, which is susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the high-temperature co-fired ceramic substrate. 【0061】(34) In the high-temperature co-fired ceramic substrate described in (32) above, a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess may have a forging surface. 【0062】 (35) In the high-temperature co-firing ceramic substrate described in (33) above, a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess may have an etched surface. 【0063】 (36) In the high-temperature co-fired ceramic substrate described in any of (32) to (35) above, it is preferable that the side surface of the first recess has a plurality of voids, the side surface of the hole has a plurality of voids, and the number of voids per unit area on the side surface of the first recess is less than the number of voids per unit area on the side surface of the hole. 【0064】 With this configuration, the mechanical strength of the first recess, which is close to the first main surface and the second main surface, which are susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the high-temperature co-fired ceramic substrate. 【0065】 (37) In the high-temperature co-fired ceramic substrate described in any of (32) to (36) above, the depth of the first recess is 10 μm to 100 μm, and the thickness of the high-temperature co-fired ceramic substrate may be 1 mm to 10 mm. 【0066】 (38) In the high-temperature co-fired ceramic substrate described in any of (32) to (37) above, the side surface of the hole may be a machined surface. 【0067】 (39) In the high-temperature co-fired ceramic substrate described in any of (32) to (38) above, the side surface of the first recess is configured to be circular in plan view, the side surface of the hole is configured to be circular in plan view, and the difference between the diameter of the first recess and the diameter of the hole may be 0.01 mm to 1 mm. 【0068】(40) In the high-temperature co-fired ceramic substrate described in any of (32) to (39) above, the high-temperature co-fired ceramic substrate has a circuit formation region, and the first recess and the hole may be located outside the circuit formation region. 【0069】 (41) The space transformer substrate according to the present invention is characterized by comprising a low-temperature co-fired ceramic substrate as described in any of (23) to (31) above. 【0070】 Because the low-temperature co-firing ceramic substrate according to the present invention suppresses chipping, its use in space transformer substrates can improve the long-term reliability of the space transformer substrates. 【0071】 (42) The space transformer substrate according to the present invention is characterized by comprising a high-temperature co-fired ceramic substrate as described in any of (32) to (40) above. 【0072】 Since the high-temperature co-firing ceramic substrate according to the present invention suppresses the occurrence of chipping, adopting it as a space transformer substrate makes it possible to improve the long-term reliability of the space transformer substrate. 【0073】 (43) The present invention is for solving the above problems and is a probe card comprising a probe card body and a space transformer substrate as described in (41) above, characterized in that the space transformer substrate is fixed to the probe card body by inserting a mechanical fastening jig through the hole. 【0074】 By fixing the space transformer substrate according to the present invention to the probe card body, the frequency of damage to the space transformer substrate is reduced, thereby enabling long-term reliability of the probe card. 【0075】(44) The present invention is for solving the above problems and is a probe card comprising a probe card body and a space transformer substrate as described in (42) above, characterized in that the space transformer substrate is fixed to the probe card body by inserting a mechanical fastening jig through the hole. 【0076】 By fixing the space transformer substrate according to the present invention to the probe card body, the frequency of damage to the space transformer substrate is reduced, thereby enabling long-term reliability of the probe card. 【0077】 (45) In the probe card described in (43) above, the mechanical fastening jig has a shaft portion and a large-diameter portion having a larger diameter than the shaft portion, and at least a part of the large-diameter portion may be in contact with the first main surface. 【0078】 With this configuration, the large-diameter portion of the mechanical fastening jig contacts the first main surface of the space transformer substrate, thereby securely fixing the space transformer substrate to the probe card body. 【0079】 (46) In the probe card described in (45) above, a space may be provided between the shaft portion of the mechanical fastening jig and the side surface of the first recess. 【0080】 With this configuration, by providing a space between the shaft of the mechanical fastening jig and the side surface of the first recess in the space transformer substrate, it is possible to prevent the shaft from contacting the side surface of the first recess. This prevents damage to the side surface of the first recess. 【0081】 (47) In the probe card described in (44) above, the mechanical fastening jig has a shaft portion and a large-diameter portion having a larger diameter than the shaft portion, and at least a part of the large-diameter portion may be in contact with the first main surface. 【0082】 With this configuration, the large-diameter portion of the mechanical fastening jig contacts the first main surface of the space transformer substrate, thereby securely fixing the space transformer substrate to the probe card body. 【0083】 (48) In the probe card described in (47) above, a space may be provided between the shaft portion of the mechanical fastening jig and the side surface of the first recess. 【0084】 With this configuration, by providing a space between the shaft of the mechanical fastening jig and the side surface of the first recess in the space transformer substrate, it is possible to prevent the shaft from contacting the side surface of the first recess. This prevents damage to the side surface of the first recess. 【0085】 According to the present invention, when forming holes in a low-temperature co-fired ceramic substrate or a high-temperature co-fired ceramic substrate used as a space transformer substrate, the occurrence of chipping can be suppressed. 【0086】 This is a side view of a probe card. This is a cross-sectional view showing a part of a probe card. This is a cross-sectional view showing a part of a probe card. This is a flowchart showing a method for manufacturing a space transformer substrate. This is a flowchart showing the hole formation process. This is a cross-sectional view showing the first recess formation process of the hole formation process. This is a cross-sectional view showing the second recess formation process of the hole formation process. This is a cross-sectional view showing the machining process of the hole formation process. This is a cross-sectional view showing a low-temperature co-fired ceramic substrate after the hole formation process. This is a plan view showing a low-temperature co-fired ceramic substrate after the hole formation process. This is an electron microscope image of the holes in a low-temperature co-fired ceramic substrate. This is a cross-sectional view showing the machining process of the hole formation process according to the second embodiment. This is a cross-sectional view showing a low-temperature co-fired ceramic substrate after the machining process according to the second embodiment. This is a cross-sectional view showing the machining process of the hole formation process according to the third embodiment. This is a cross-sectional view showing a low-temperature co-fired ceramic substrate after the machining process according to the third embodiment. This is a cross-sectional view showing a low-temperature co-fired ceramic substrate after the machining process of the hole formation process according to the fourth embodiment. This is a cross-sectional view showing the first recess formation process according to the fifth embodiment. This is a cross-sectional view showing the second recess formation process according to the fifth embodiment. This is a cross-sectional view showing the first recess formation process and the second recess formation process according to the sixth embodiment. 【0087】Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Figures 1 to 11 show a first embodiment of the probe card and its manufacturing method according to the present invention. 【0088】 As shown in Figure 1, the probe card 1 comprises a probe card body 2, a space transformer substrate 3, a support member 4, and connecting jigs 5a and 5b. 【0089】 The probe card body 2 includes a disc-shaped printed circuit board and an interface for connecting to a tester device. In addition, the probe card body 2 has a through hole 2a through which a part of the connecting jig 5a is inserted. 【0090】 The probe card body 2 is connected to the space transformer substrate 3 via a support member 4 and connecting jigs 5a and 5b. The support member 4 is positioned between the probe card body 2 and the space transformer substrate 3. The support member 4 is cylindrical in shape, and a portion of the connecting jig 5a can be inserted inside it. 【0091】 The space transformer board 3 is a wiring board that has the function of converting the wiring pitch on one main surface side to that on the other main surface side, and is also called an ST board. The space transformer board 3 is electrically connected to the probe card body 2 through wiring (not shown). 【0092】 As shown in Figure 1, the space transformer substrate 3 comprises a low-temperature co-fired ceramic substrate 6, a plurality of electrode pads 7 formed on the main surface of the low-temperature co-fired ceramic substrate 6, and a plurality of probes 8 fixed to the electrode pads 7. The space transformer substrate 3 may also include a high-temperature co-fired ceramic substrate instead of the low-temperature co-fired ceramic substrate 6. 【0093】 The low-temperature co-fired ceramic substrate 6 is, for example, a multilayer substrate made of a composite material including glass and ceramics. The term "glass" here includes not only general glass but also glass ceramics. On the other hand, the high-temperature co-fired ceramic substrate is a multilayer substrate formed solely of ceramics. 【0094】The glass contained in the glass-ceramics of the low-temperature co-fired ceramic substrate 6, for example, as a glass composition, in mass %, preferably, SiO ２ : 50 to 80%, B ２ O ３ : 0 to 30%, Li ２ O + Na ２ O + K ２ O: 0 to 10%, MgO + CaO + SrO + BaO: 0 to 30%, and TiO ２ : 0 to 10% is contained, and more preferably, SiO ２ : 60 to 80%, B ２ O ３ : 5 to 30%, Li ２ O + Na ２ O + K ２ O: 1 to 5%, MgO + CaO + SrO + BaO: 5 to 20%, and TiO ２ : 0.1 to 3% is contained. The composition of the glass may contain, as other oxides, for example, in mass %, ZrO ２ : 0.1 to 3%. 【0095】 As the ceramics contained in the glass-ceramics of the low-temperature co-fired ceramic substrate 6, for example, Zn ２ SiO ４ (willemite), Al ２ O ３ (alumina), cordierite, AlN (aluminum nitride), zirconium phosphate-based compounds, ZrSiO ４ (zircon), ZrO ２ (zirconia), TiO ２ (titanium oxide), SnO ２ (tin oxide), β-quartz solid solution, β-eucryptite, β-spodumene, etc. may be mentioned. One kind or two or more kinds of ceramics can be used. 【0096】 The mixing ratio of the glass and ceramics of the low-temperature co-fired ceramic substrate 6 is, in volume %, preferably, glass: 30 to 90%, ceramics: 10 to 70%, more preferably, glass: 40 to 80%, ceramics: 20 to 60%, and still more preferably, glass: 50 to 70%, ceramics: 30 to 50%. 【0097】The following description will use an embodiment using a low-temperature co-firing ceramic substrate 6, but the same embodiment can be adopted when using a high-temperature co-firing ceramic substrate. Except for the specific conditions when using a high-temperature co-firing ceramic substrate, a detailed description of the embodiment using a high-temperature co-firing ceramic substrate will be omitted. 【0098】 The low-temperature co-fired ceramic substrate 6 is constructed in the shape of a regular polygon. The low-temperature co-fired ceramic substrate 6 is preferably a flat plate with a certain thickness, which is 1 mm to 10 mm, preferably 3 mm to 6 mm. In this embodiment, the low-temperature co-fired ceramic substrate 6 is a regular hexagon, and its diameter (diagonal length) is preferably 4 inches, 6 inches, 8 inches, or 12 inches. 【0099】 The low-temperature co-fired ceramic substrate 6 has a first main surface Sa and a second main surface Sb located on the opposite side of the first main surface Sa. The low-temperature co-fired ceramic substrate 6 also has a circuit formation region CA. The circuit formation region CA is the region where the circuit and internal wiring are formed. 【0100】 As shown in Figure 1, the low-temperature co-fired ceramic substrate 6 has a first recess 9 formed on the first main surface Sa side, a second recess 10 formed on the second main surface Sb side, and a plurality of holes 11 that penetrate from the first recess 9 to the second recess 10, outside the circuit formation region CA. The detailed configuration of the first recess 9, the second recess 10 and the holes 11 will be described later. 【0101】 The electrode pad 7 is a metal terminal for connecting the probe 8 to the low-temperature co-fired ceramic substrate 6. The electrode pad 7 has an electrode layer and a bonding layer for bonding the probe 8 to the electrode layer. 【0102】 The probe 8 is a component that contacts the chip on the semiconductor wafer to be inspected, and is, for example, a component with a needle-shaped tip. The probe 8 is positioned to correspond to the location of the semiconductor chip and is bonded to a plurality of electrode pads 7 formed on the space transformer substrate 3. Any metallic material can be used as the material for the probe 8, and examples include alloys such as palladium alloy, beryllium copper alloy, and tungsten alloy. 【0103】 The connecting jigs 5a and 5b include a first connecting jig 5a and a second connecting jig 5b. The first connecting jig 5a is made of, for example, a bolt having a male threaded portion on its shaft. However, it is not limited to this, and the first connecting jig 5a does not need to have a male thread formed on its shaft. The second connecting jig 5b is made of a nut that can be attached to the shaft of the bolt. In this embodiment, the first connecting jig 5a and the second connecting jig 5b constitute a mechanical fastening jig. 【0104】 As shown in Figure 1, the first connecting jig 5a is inserted through the through hole 2a of the probe card body 2, the support member 4, and the hole 11 of the space transformer substrate 3. The probe card body 2 and the space transformer substrate 3 can be connected by fitting the second connecting jig 5b onto the end of the first connecting jig 5a and fastening it. 【0105】 Specifically, as shown in Figures 2 and 3, the first connecting jig 5a has a shaft portion 5a1 and a head portion 5a2 which is a larger diameter portion than the shaft portion 5a1. The second connecting jig 5b is a larger diameter portion than the shaft portion 5a1 of the first connecting jig 5a, similar to the head portion of the first connecting jig 5a. 【0106】 As shown in Figure 2, the first recess 9 of the low-temperature co-fired ceramic substrate 6 has a side surface 9a and a bottom surface 9b. The second recess 10 of the low-temperature co-fired ceramic substrate 6 also has a side surface 10a and a bottom surface 10b. 【0107】 As shown in Figure 2, the end of the shaft portion 5a1 of the first connecting jig 5a protrudes toward the first main surface Sa of the low-temperature co-fired ceramic substrate 6. The second connecting jig 5b is attached to the end of the shaft portion 5a1 of the first connecting jig 5a. The diameter (outer diameter) Db of the second connecting jig 5b is larger than the diameter D1 of the side surface 9a in the first recess 9 of the low-temperature co-fired ceramic substrate 6. Therefore, the second connecting jig 5b is located outside the first recess 9 and covers the entire first recess 9. Furthermore, a part of the second connecting jig 5b is in contact with the first main surface Sa of the low-temperature co-fired ceramic substrate 6. 【0108】The diameter Da1 of the shaft portion 5a1 in the first connecting jig 5a is smaller than the diameter D1 of the side surface 9a of the first recess 9. As a result, as shown in Figure 2, a space SP1 is formed between the shaft portion 5a1 of the first connecting jig 5a and the side surface 9a of the first recess 9. 【0109】 The diameter Da1 of the shaft portion 5a1 in the first connecting jig 5a is smaller than the diameter D2 of the side surface 10a of the second recess 10. As a result, as shown in Figure 2, a space SP2 is formed between the shaft portion 5a1 of the first connecting jig 5a and the side surface 10a of the second recess 10. 【0110】 Figure 3 shows another example of the connection configuration of the space transformer substrate 3 using mechanical fastening jigs (first connecting jig 5a and second connecting jig 5b). In the examples shown in Figures 1 and 2, the head 5a2 of the first connecting jig 5a is located on the probe card body 2 side, but in this example, it is located on the low-temperature co-fired ceramic substrate 6 side. 【0111】 Specifically, the diameter Da2 of the head 5a2 of the first connecting jig 5a is larger than the diameter D1 of the side surface 9a in the first recess 9 of the low-temperature co-fired ceramic substrate 6. Therefore, in this example, a portion of the head 5a2 of the first connecting jig 5a is located outside the first recess 9, covering the side surface 9a of the first recess 9 and in contact with the first main surface Sa of the low-temperature co-fired ceramic substrate 6. 【0112】 The following describes a method for manufacturing the probe card 1, and more particularly, a method for manufacturing the space transformer substrate 3. As shown in Figure 4, this method comprises a preparation step S1, a lamination step S2, a firing step S3, a hole formation step S4, a plating step S5, and a fixing step S6. 【0113】 Preparation step S1 is a step of preparing multiple green sheets made of ceramic sheets. The thickness of one green sheet is preferably 0.05 mm or more and 0.25 mm or less. Multiple via holes are formed through the green sheet. In addition, a predetermined wiring pattern is formed on the green sheet by means of screen printing or other means. 【0114】Lamination process S2 is a process in which multiple green sheets are stacked on top of each other to form a laminate. In lamination process S2, the multiple green sheets are integrated by heating and pressing the laminate together to obtain the laminate. 【0115】 In firing step S3, the laminate composed of green sheets is heated and fired. In firing step S3, the laminate placed in the heating furnace is heated to a temperature of, for example, 800°C to 900°C. This forms a low-temperature co-fired ceramic substrate 6. In firing step S3, when firing a high-temperature co-fired ceramic substrate, the laminate placed in the heating furnace is heated to a temperature of, for example, 1500°C to 1600°C. 【0116】 The hole formation step S4 is a step in which a first recess 9, a second recess 10, and a hole 11 are formed in the low-temperature co-fired ceramic substrate 6 after the firing step S3. As shown in Figure 5, the hole formation step S4 comprises a first recess formation step S41, a second recess formation step S42, and a machining step S43. In the hole formation step S4, before carrying out each of the above steps, grinding is performed on the outer periphery of the low-temperature co-fired ceramic substrate 6, and polishing is performed on the first main surface Sa and the second main surface Sb of the low-temperature co-fired ceramic substrate 6. 【0117】 As shown in Figure 6, in the first recess formation step S41, laser light L is irradiated from the laser irradiation device 12 onto the first main surface Sa of the low-temperature co-fired ceramic substrate 6. In this embodiment, in order to form the first recess 9 which is circular in plan view, the laser light L is irradiated onto the first main surface Sa of the low-temperature co-fired ceramic substrate 6 while scanning in a circular manner. The irradiation position of the laser light L is preferably outside the circuit formation region CA on the low-temperature co-fired ceramic substrate 6. 【0118】As shown in Figure 7, the first recess 9 has a side surface 9a and a bottom surface 9b, as well as a protrusion 9c formed on the edge of the side surface 9a. As shown in Figure 10, the side surface 9a and the bottom surface 9b are circular in shape when viewed from above. The diameter of the first recess 9 (diameter of the side surface 9a) is preferably 1 mm or more and 20 mm or less. The depth of the first recess 9 is preferably less than the thickness of the single green sheet prepared in preparation step S1. The depth of the first recess 9 is preferably 10 μm or more and 100 μm or less. 【0119】 The protruding portion 9c is configured to protrude from the first main surface Sa at the edge of the side surface 9a. The protruding portion 9c is configured in an annular shape so as to surround the side surface 9a. The protruding portion 9c is formed when a laser beam L is irradiated onto the first main surface Sa of the low-temperature co-fired ceramic substrate 6, causing a portion of the molten first main surface Sa to bulge. 【0120】 As shown in Figure 7, the second recess formation step S42 is a step in which, after the first recess formation step S41, a second recess 10 is formed on the second main surface Sb of the low-temperature co-fired ceramic substrate 6 at a position opposite to the first recess 9. In the second recess formation step S42, the second main surface Sb is irradiated with laser light L while scanning, similar to the case in which the first recess 9 is formed. Preferably, the second recess 10 is formed concentrically with the first recess 9. 【0121】 As shown in Figure 8, the second recess 10 has a side surface 10a and a bottom surface 10b, as well as a protrusion 10c formed on the edge of the side surface 10a. The side surface 10a and bottom surface 10b of the second recess 10 are preferably configured in a circular shape in plan view, similar to the side surface 9a and bottom surface 9b of the first recess 9. The diameter of the second recess 10 (diameter of the side surface 10a) is preferably 1 mm or more and 20 mm or less. The depth of the second recess 10 is preferably less than the thickness of the single green sheet prepared in preparation step S1. The depth of the second recess 10 is preferably 10 μm or more and 100 μm or less. 【0122】The machining process S43 is a process of forming a hole 11 by machining from the bottom surface 9b of the first recess 9 of the low-temperature co-fired ceramic substrate 6 toward the second main surface Sb. As shown in Figure 8, in the machining process S43, the hole 11 is formed by a machining tool 13 (for example, an electroplated drill) having a diameter smaller than the diameter of the side surface 9a of the first recess 9. 【0123】 After contacting the bottom surface 9b of the first recess 9, the processing tool 13 moves along the thickness direction of the low-temperature co-fired ceramic substrate 6 and reaches the second recess 10 of the second main surface Sb. Subsequently, as the processing tool 13 penetrates the bottom surface 10b of the second recess 10, a hole 11 is formed that penetrates from the bottom surface 9b of the first recess 9 to the bottom surface 10b of the second recess 10, as shown in Figure 9. 【0124】 As shown in Figure 9, the depth of the first recess 9 is shallower than the depth (length) of the hole 11. As shown in Figure 10, the hole 11 has a circular side surface 11a in plan view. The diameter of the side surface 11a is larger than the diameter of the via hole formed in the circuit formation region CA. The diameter of the hole 11 is preferably 1 mm or more and 20 mm or less. 【0125】 The diameter D3 of the side surface 11a of the hole 11 is smaller than the diameter D1 of the side surface 9a of the first recess 9. Similarly, the diameter D3 of the side surface 11a of the hole 11 is smaller than the diameter D2 of the side surface 10a of the second recess 10. Preferably, the difference between the diameter D1 of the side surface 9a of the first recess 9 and the diameter D3 of the hole 11 is 0.01 mm or more and 1 mm or less. Similarly, preferably, the difference between the diameter D2 of the side surface 10a of the second recess 10 and the diameter D3 of the hole 11 is 0.01 mm or more and 1 mm or less. 【0126】 In this embodiment, the first recess 9 is a single recess connected to the hole 11. After the machining process S43, the first recess 9 is composed of a side surface 9a and a bottom surface 9b remaining between the side surface 11a of the hole 11. 【0127】As shown in Figure 10, four first recesses 9, second recesses 10, and holes 11 are formed in the region outside the circuit formation area CA of the low-temperature co-fired ceramic substrate 6. The number of first recesses 9, second recesses 10, and holes 11 is not limited to this embodiment. Preferably, the number of first recesses 9, second recesses 10, and holes 11 formed in the low-temperature co-fired ceramic substrate 6 is between 2 and 8. 【0128】 Figure 11 shows an electron microscope image of the side surface 11a of the hole 11. Compared to a normal glass substrate, the low-temperature co-fired ceramic substrate 6 has a relatively large number of minute voids (air spaces) VD formed inside by the firing process S3. These voids VD are exposed on the side surface 11a of the hole 11 by the machining process S43. Although not shown, similar minute voids (air spaces) are also formed on the side surface 9a and bottom surface 9b of the first recess 9, and on the side surface 10a and bottom surface 10b of the second recess 10. 【0129】 The unit area (1 mm²) on the side surface 9a of the first recess 9 or the side surface 10a of the second recess 10 ２ The number of voids per unit area (1 mm²) on the side surface 11a of the hole 11 is equal to the number of voids per unit area (1 mm²). ２ This is less than the number of voids per unit area. 【0130】 The side surface 9a of the first recess 9 and the side surface 10a of the second recess 10 are forged surfaces formed by irradiation with laser light L in the first recess formation step S41 and the second recess formation step S42 of the hole formation step S4. Forged surfaces are molten surfaces formed by the melting of the side surface 10a of the second recess 10 due to irradiation with laser light L. Also, the side surface 11a of the hole 11 is a machined surface formed by the machining step S43 of the hole formation step S4. In other words, the formation of forged surfaces (molten surfaces) in the first recess 9 and the second recess 10 makes it difficult for voids in the low-temperature co-fired ceramic substrate 6 to surface. As a result, the number of voids that surface on the forged surfaces (molten surfaces) is less than the number of voids VD that surface on the machined surfaces. Consequently, the mechanical strength of the first recess 9, which is close to the first main surface Sa and the second main surface Sb, which are susceptible to external influences (external forces, etc.), is relatively increased, and as a result, it becomes easier to avoid damage to the low-temperature co-fired ceramic substrate 6. 【0131】 Plating step S5 is a step in which a plating treatment is applied to the low-temperature co-fired ceramic substrate 6 after the hole formation step S4. In plating step S5, the low-temperature co-fired ceramic substrate 6 is immersed in a plating solution contained in a plating tank, and a plating treatment (for example, electroless nickel / gold plating) is applied to its entire surface. 【0132】 In the fixing process S6, electrode pads 7 are formed on the low-temperature co-fired ceramic substrate 6 after the plating process S5. The electrode pads 7 are formed on the first main surface Sa of the low-temperature co-fired ceramic substrate 6, for example, by using a known film formation method. 【0133】 Furthermore, in the fixing process S6, the probes 8 are fixed to the low-temperature co-fired ceramic substrate 6 after the plating process S5. In the fixing process S6, multiple probe tips are bonded to electrode pads 7 formed in the circuit formation region CA of the low-temperature co-fired ceramic substrate 6. As a result, a space transformer substrate 3 is manufactured in which the probes 8 are fixed to the low-temperature co-fired ceramic substrate 6. 【0134】 Next, a support member 4 is interposed between the probe card body 2 and the space transformer substrate 3. Then, the shaft portion of the first connecting jig 5a is inserted through the through hole 2a of the probe card body 2, the inside of the support member 4, and the hole 11 of the space transformer substrate 3. After that, the probe card 1 is assembled by attaching the second connecting jig 5b to the end of the first connecting jig 5a and tightening it. 【0135】According to the manufacturing method of the probe card 1 (space transformer substrate 3) of this embodiment described above, a first recess 9 is formed in the first recess formation step S41 by heating the first main surface Sa of the low-temperature co-fired ceramic substrate 6 by irradiating it with laser light L. Subsequently, in the second recess formation step S42, a second recess 10 is formed by heating the second main surface Sb of the low-temperature co-fired ceramic substrate 6 by irradiating it with laser light L. The first recess 9 is formed by melting the first main surface Sa, and the second recess 10 is formed by melting the second main surface Sb. The resulting forged surface (molten surface) is less prone to chipping when the machining step S43 is performed. 【0136】 In machining step S43, the hole 11 is formed by machining so as to penetrate from the bottom surface 9b of the first recess 9 to the bottom surface 10b of the second recess 10. Therefore, the occurrence of chipping by the machining tool 13 can be suppressed on the bottom surface 9b of the first recess 9 and the bottom surface 10b of the second recess 10. 【0137】 Figures 12 and 13 show a second embodiment of the manufacturing method for a space transformer substrate. In this embodiment, as shown in Figure 12, the machining process S43 is completed without penetrating the machining tool 13 to the bottom surface 10b of the second recess 10. Therefore, in the low-temperature co-fired ceramic substrate 6, the hole 11 connected to the first recess 9 does not penetrate to the second recess 10. 【0138】 In other words, in this embodiment, the hole 11 has a bottom surface 11b in addition to a side surface 11a. The bottom surface 11b of the hole 11 is formed in the vicinity of the bottom surface 10b of the second recess 10. The distance between the bottom surface 11b of the hole 11 and the bottom surface 10b of the second recess 10 is preferably 0.01 mm or more and 0.20 mm or less. This distance is preferably 1% or more and 5% or less of the thickness of the low-temperature co-fired ceramic substrate 6. 【0139】 In this embodiment, a second machining process may be performed on the bottom surface 10b of the second recess 10 to cause the hole 11 to penetrate the bottom surface 10b of the second recess 10. 【0140】Figures 14 and 15 show a third embodiment of the method for manufacturing a space transformer substrate. In this embodiment, as shown in Figure 14, the second recess formation step S42 is omitted in the hole formation step S4, and the machining step S43 is performed. 【0141】 Therefore, as shown in Figure 15, the second recess 10 is not formed on the second main surface Sb of the low-temperature co-fired ceramic substrate 6. The hole 11 penetrates from the bottom surface 9b of the first recess 9 to the second main surface Sb. 【0142】 Figure 16 shows a fourth embodiment of the method for manufacturing a space transformer substrate. In this embodiment, similar to the third embodiment, the second recess formation step S42 is omitted in the hole formation step S4. Also, the machining step S43 is completed without the hole 11 connected to the first recess 9 penetrating through to the second main surface Sb of the low-temperature co-fired ceramic substrate 6. As a result, the hole 11 of the low-temperature co-fired ceramic substrate 6 does not penetrate to the second main surface Sb. In addition to the side surface 11a, the hole 11 has a bottom surface 11b located near the second main surface Sb. Preferably, the distance between the bottom surface 11b of the hole 11 and the second main surface Sb is 1% or more and 5% or less of the thickness of the low-temperature co-fired ceramic substrate 6. 【0143】 In this embodiment, a second machining process may be performed on the second main surface Sb to cause the hole 11 to penetrate the second main surface Sb. 【0144】 Figures 17 and 18 show a fifth embodiment of the method for manufacturing a space transformer substrate. In this embodiment, the first recess formation step S41 and the second recess formation step S42 in the hole formation step S4 differ from those of the other embodiments. 【0145】 As shown in Figure 17, in the first recess formation step S41, the first main surface Sa of the low-temperature co-fired ceramic substrate 6 is subjected to an etching process to form a first recess 9 on the first main surface Sa. Specifically, in the first recess formation step S41, a first mask portion 14 is formed on the first main surface Sa of the low-temperature co-fired ceramic substrate 6, and a second mask portion 15 is formed on the second main surface Sb. 【0146】The first mask portion 14 has an opening (hereinafter referred to as the "first opening") 14a for forming the first recess 9 in the low-temperature co-fired ceramic substrate 6. As a result, a portion of the low-temperature co-fired ceramic substrate 6 corresponding to the first opening 14a is exposed. Note that in the first recess formation step S41, no opening is formed in the second mask portion 15. 【0147】 In the first recess formation step S41, the low-temperature co-fired ceramic substrate 6 is immersed in the etching solution EL contained in the etching tank ET. As a result, the etching solution EL comes into contact with a part of the first main surface Sa of the low-temperature co-fired ceramic substrate 6 through the first opening 14a of the first mask portion 14. The etching solution EL does not come into contact with the first main surface Sa covered by the first mask portion 14 or the second main surface Sb covered by the second mask portion 15 of the low-temperature co-fired ceramic substrate 6. After a predetermined time has elapsed, a first recess 9 of a predetermined depth is formed in a part of the first main surface Sa of the low-temperature co-fired ceramic substrate 6. The side surface 9a and bottom surface 9b of the first recess 9 are composed of surfaces formed by the etching process (hereinafter referred to as "etched surfaces"). 【0148】 As shown in Figure 18, in the second recess formation step S42, after the first recess formation step S41, the second main surface Sb of the low-temperature co-fired ceramic substrate 6 is subjected to an etching process to form the second recess 10 on the second main surface Sb. In the second recess formation step S42, the first opening 14a of the first mask portion 14 is closed, or a first mask portion 14 without an opening is formed on the first main surface Sa of the low-temperature co-fired ceramic substrate 6. As a result, the entire surface of the first main surface Sa of the low-temperature co-fired ceramic substrate 6, including the first recess 9, is covered by the first mask portion 14. The second mask portion 15 formed on the second main surface Sb of the low-temperature co-fired ceramic substrate 6 has an opening (hereinafter referred to as the "second opening") 15a for forming the second recess 10 on the second main surface Sb of the low-temperature co-fired ceramic substrate 6. 【0149】In the second recess formation step S42, the low-temperature co-fired ceramic substrate 6 is immersed in the etching solution EL of the etching tank ET, similar to the first recess formation step S41. As a result, the etching solution EL comes into contact with a portion of the second main surface Sb of the low-temperature co-fired ceramic substrate 6 through the second opening 15a of the second mask portion 15. After a predetermined time has elapsed, a second recess 10 of a predetermined depth is formed in a portion of the second main surface Sb of the low-temperature co-fired ceramic substrate 6. The side surface 10a and bottom surface 10b of the second recess 10 are composed of etched surfaces. 【0150】 According to the embodiment described above, by configuring the side surface 9a and bottom surface 9b of the first recess 9 as etched surfaces, chipping is less likely to occur when the machining process S43 is performed. 【0151】 Figure 19 shows a sixth embodiment of the method for manufacturing a space transformer substrate. In this embodiment, the first recess formation step S41 and the second recess formation step S42 in the hole formation step S4 differ from those of the other embodiments. 【0152】 In the fifth embodiment described above, the second recess formation step S42 was performed after the first recess formation step S41. However, in this embodiment, the first recess formation step S41 and the second recess formation step S42 are performed simultaneously. 【0153】 As shown in Figure 19, the first mask portion 14 formed on the first main surface Sa of the low-temperature co-fired ceramic substrate 6 has a first opening 14a. Similarly, the second mask portion 15 formed on the second main surface Sb of the low-temperature co-fired ceramic substrate 6 has a second opening 15a. When the low-temperature co-fired ceramic substrate 6 is immersed in the etching solution EL of the etching tank ET, a portion of the first main surface Sa is etched through the first opening 14a, and a portion of the second main surface Sb is etched through the second opening 15a. After a predetermined time has elapsed, a first recess 9 and a second recess 10 of a predetermined depth are formed in the low-temperature co-fired ceramic substrate 6. The side surface 9a and bottom surface 9b of the first recess 9 and the side surface 10a and bottom surface 10b of the second recess 10 are composed of etched surfaces. 【0154】Furthermore, the present invention is not limited to the configuration of the above embodiments, nor is it limited to the effects described above. The present invention can be modified in various ways without departing from the spirit of the invention. 【0155】 In the above embodiment, a hole formation step S4 was shown in which a first recess formation step S41 was performed by irradiation with laser light L, followed by a second recess formation step S42 also performed by irradiation with laser light L. However, the present invention is not limited to this configuration. For example, the first recess formation step S41 and the second recess formation step S42 may be performed simultaneously. 【0156】 In the fifth and sixth embodiments described above, the etching process was performed only on a portion of the first main surface Sa of the low-temperature co-fired ceramic substrate 6 in the first recess formation step S41. However, the present invention is not limited to this configuration. For example, the etching process may be performed on the entire surface Sa of the first main surface Sa of the low-temperature co-fired ceramic substrate 6 before the execution of the first recess formation step S41. Similarly, the etching process may be performed on the entire surface Sb of the second main surface Sb of the low-temperature co-fired ceramic substrate 6 before the execution of the second recess formation step S42. 【0157】 In the fifth and sixth embodiments described above, the second recess formation step S42 may be omitted, and the machining step S43 may be performed after the first recess formation step S41. 【0158】1 Probe card 2 Probe card body 3 Space transformer substrate 5a First connecting jig 5b Second connecting jig 6 Low-temperature co-firing ceramic substrate 9 First recess 9a Side surface of the first recess 9b Bottom surface of the first recess 9c Annular projection 10 Second recess 11 Hole 11a Side surface of the hole 13 Machining tool CA Circuit formation area L Laser light Sa First main surface of low-temperature co-firing ceramic substrate Sb Second main surface of low-temperature co-firing ceramic substrate S1 Preparation process S3 Firing process S4 Hole formation process S41 First recess formation process S42 Second recess formation process S43 Machining process VD Void

Claims

1. A method for manufacturing a low-temperature co-fired ceramic substrate, comprising: a firing step of firing the low-temperature co-fired ceramic substrate; and a hole-forming step of forming holes in the low-temperature co-fired ceramic substrate after firing, wherein the low-temperature co-fired ceramic substrate has a first main surface and a second main surface located opposite to the first main surface, and the hole-forming step includes: a first recess-forming step of forming a first recess by irradiating the first main surface of the low-temperature co-fired ceramic substrate with laser light; and a machining step of forming holes by machining from the first recess toward the second main surface of the low-temperature co-fired ceramic substrate.

2. A method for manufacturing a low-temperature co-fired ceramic substrate, comprising: a firing step of firing the low-temperature co-fired ceramic substrate; and a hole-forming step of forming holes in the low-temperature co-fired ceramic substrate after firing, wherein the low-temperature co-fired ceramic substrate has a first main surface and a second main surface located opposite to the first main surface, and the hole-forming step includes: a first recess-forming step of forming a first recess by etching the first main surface of the low-temperature co-fired ceramic substrate; and a machining step of forming holes by machining from the first recess toward the second main surface of the low-temperature co-fired ceramic substrate.

3. The method for manufacturing a low-temperature co-firing ceramic substrate according to claim 1, comprising a second recess formation step, which is performed after the first recess formation step and before the machining step, in which a second recess is formed on the second main surface of the low-temperature co-firing ceramic substrate at a position opposite to the first recess, wherein the second recess formation step is characterized in that laser light is irradiated onto the second main surface.

4. The method for manufacturing a low-temperature co-firing ceramic substrate according to claim 2, comprising a second recess formation step, which is performed after the first recess formation step and before the machining step, in which a second recess is formed on the second main surface of the low-temperature co-firing ceramic substrate at a position opposite to the first recess, wherein the second recess is formed in the second recess formation step by performing an etching treatment on the second main surface.

5. A method for manufacturing a low-temperature co-firing ceramic substrate according to any one of claims 1 to 4, characterized in that the depth of the first recess is shallower than the depth of the hole.

6. The method for manufacturing a low-temperature co-firing ceramic substrate according to any one of claims 1 to 4, characterized in that the holes do not penetrate to the second main surface.

7. The method for manufacturing a low-temperature co-firing ceramic substrate according to any one of claims 1 to 4, characterized in that the hole penetrates to the second main surface.

8. The method for manufacturing a low-temperature co-firing ceramic substrate according to claim 3 or 4, characterized in that the hole penetrates to the second recess.

9. A method for manufacturing a low-temperature co-firing ceramic substrate according to any one of claims 1 to 4, comprising a preparation step of preparing a green sheet before the firing step, wherein the depth of the first recess is less than the thickness of one of the green sheets.

10. The method for manufacturing a low-temperature co-firing ceramic substrate according to any one of claims 1 to 4, characterized in that the first recess has a side surface and a bottom surface formed between the side surface and the hole.

11. The method for manufacturing a low-temperature co-firing ceramic substrate according to claim 10, characterized in that the side surface of the first recess is formed in a circular shape in plan view, and in the machining process, the hole is formed by a machining tool having a diameter smaller than the diameter of the side surface.

12. A method for manufacturing a high-temperature co-fired ceramic substrate, comprising: a firing step of firing the high-temperature co-fired ceramic substrate; and a hole-forming step of forming holes in the high-temperature co-fired ceramic substrate after firing, wherein the high-temperature co-fired ceramic substrate has a first main surface and a second main surface located opposite to the first main surface, and the hole-forming step includes: a first recess-forming step of forming a first recess by irradiating the first main surface of the high-temperature co-fired ceramic substrate with laser light; and a machining step of forming holes by machining from the first recess toward the second main surface of the high-temperature co-fired ceramic substrate.

13. A method for manufacturing a high-temperature co-firing ceramic substrate, comprising: a firing step of firing the high-temperature co-firing ceramic substrate; and a hole-forming step of forming holes in the high-temperature co-firing ceramic substrate after firing, wherein the high-temperature co-firing ceramic substrate has a first main surface and a second main surface located opposite to the first main surface, and the hole-forming step includes: a first recess-forming step of forming a first recess by etching the first main surface of the high-temperature co-firing ceramic substrate; and a machining step of forming holes by machining from the first recess toward the second main surface of the high-temperature co-firing ceramic substrate.

14. The method for manufacturing a high-temperature co-firing ceramic substrate according to claim 12, comprising a second recess formation step, which is performed after the first recess formation step and before the machining step, in which a second recess is formed on the second main surface of the high-temperature co-firing ceramic substrate at a position opposite to the first recess, wherein in the second recess formation step, laser light is irradiated onto the second main surface.

15. A method for manufacturing a high-temperature co-fired ceramic substrate according to claim 13, comprising a second recess formation step in which a second recess is formed on the second main surface of the high-temperature co-fired ceramic substrate at a position opposite to the first recess, wherein the second recess is formed in the second recess formation step by applying an etching treatment to the second main surface.

16. A method for manufacturing a high-temperature co-firing ceramic substrate according to any one of claims 12 to 15, characterized in that the depth of the first recess is shallower than the depth of the hole.

17. The method for manufacturing a high-temperature co-firing ceramic substrate according to any one of claims 12 to 15, characterized in that the holes do not penetrate to the second main surface.

18. The method for manufacturing a high-temperature co-firing ceramic substrate according to any one of claims 12 to 15, characterized in that the hole penetrates to the second main surface.

19. The method for manufacturing a high-temperature co-firing ceramic substrate according to claim 14 or 15, characterized in that the hole penetrates to the second recess.

20. A method for manufacturing a high-temperature co-firing ceramic substrate according to any one of claims 12 to 15, comprising a preparation step of preparing a green sheet before the firing step, wherein the depth of the first recess is less than the thickness of one of the green sheets.

21. The method for manufacturing a high-temperature co-firing ceramic substrate according to any one of claims 12 to 15, characterized in that the first recess has a side surface and a bottom surface formed between the side surface and the hole.

22. The method for manufacturing a high-temperature co-firing ceramic substrate according to claim 21, characterized in that the side surface of the first recess is formed in a circular shape in plan view, and in the machining step, the hole is formed by a machining tool having a diameter smaller than the diameter of the side surface.

23. A low-temperature co-fired ceramic substrate having a first main surface and a second main surface located opposite to the first main surface, wherein the substrate has a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, the first recess having a side surface and a bottom surface formed between the side surface and the hole, the first recess being located on the first main surface side, the hole having a side surface and being located on the second main surface side, the side surface of the first recess being a forging surface, at least a portion of the bottom surface of the first recess being a forging surface, and in plan view, the hole being smaller than the first recess.

24. A low-temperature co-fired ceramic substrate having a first main surface and a second main surface located opposite to the first main surface, wherein the first recess is formed extending from the first main surface toward the second main surface and a hole is connected to the first recess, the first recess has a side surface and a bottom surface formed between the side surface and the hole, the first recess is located toward the first main surface, the hole has a side surface and is located toward the second main surface, the side surface of the first recess is an etched surface, at least a portion of the bottom surface of the first recess is an etched surface, and in plan view, the hole is smaller than the first recess.

25. The low-temperature co-firing ceramic substrate according to claim 23, characterized in that a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess has a forging surface.

26. The low-temperature co-firing ceramic substrate according to claim 24, characterized in that a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess has an etched surface.

27. The low-temperature co-fired ceramic substrate according to any one of claims 22 to 25, characterized in that the side surface of the first recess has a plurality of voids, the side surface of the hole has a plurality of voids, and the number of voids per unit area on the side surface of the first recess is less than the number of voids per unit area on the side surface of the hole.

28. The low-temperature co-fired ceramic substrate according to any one of claims 22 to 25, characterized in that the depth of the first recess is 10 μm to 100 μm, and the thickness of the low-temperature co-fired ceramic substrate is 1 mm to 10 mm.

29. The low-temperature co-firing ceramic substrate according to any one of claims 22 to 25, characterized in that the side surface of the hole is a machined surface.

30. The low-temperature co-fired ceramic substrate according to any one of claims 22 to 25, characterized in that the side surface of the first recess is configured in a circular shape in a plan view, the side surface of the hole is configured in a circular shape in a plan view, and the difference between the diameter of the first recess and the diameter of the hole is 0.01 mm to 1 mm.

31. The low-temperature co-fired ceramic substrate according to any one of claims 22 to 25, characterized in that the low-temperature co-fired ceramic substrate has a circuit formation region, and the first recess and the hole are located outside the circuit formation region.

32. A high-temperature co-fired ceramic substrate having a first main surface and a second main surface located opposite to the first main surface, wherein the substrate has a first recess formed from the first main surface toward the second main surface and a hole connected to the first recess, the first recess having a side surface and a bottom surface formed between the side surface and the hole, the first recess being located on the first main surface side, the hole having a side surface and being located on the second main surface side, the side surface of the first recess being a forging surface, at least a portion of the bottom surface of the first recess being a forging surface, and in plan view, the hole being smaller than the first recess.

33. A high-temperature co-fired ceramic substrate having a first main surface and a second main surface located opposite to the first main surface, wherein the first recess is formed extending from the first main surface toward the second main surface and a hole is connected to the first recess, the first recess has a side surface and a bottom surface formed between the side surface and the hole, the first recess is located toward the first main surface, the hole has a side surface and is located toward the second main surface, the side surface of the first recess is an etched surface, at least a portion of the bottom surface of the first recess is an etched surface, and in plan view, the hole is smaller than the first recess.

34. The high-temperature co-firing ceramic substrate according to claim 32, characterized in that a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess has a forging surface.

35. The high-temperature co-firing ceramic substrate according to claim 33, characterized in that a second recess is provided on a part of the second main surface corresponding to the first recess, and the second recess has an etched surface.

36. The high-temperature co-fired ceramic substrate according to any one of claims 32 to 35, characterized in that the side surface of the first recess has a plurality of voids, the side surface of the hole has a plurality of voids, and the number of voids per unit area on the side surface of the first recess is less than the number of voids per unit area on the side surface of the hole.

37. The high-temperature co-fired ceramic substrate according to any one of claims 32 to 35, characterized in that the depth of the first recess is 10 μm to 100 μm, and the thickness of the high-temperature co-fired ceramic substrate is 1 mm to 10 mm.

38. The high-temperature co-fired ceramic substrate according to any one of claims 32 to 35, characterized in that the side surface of the hole is a machined surface.

39. The high-temperature co-fired ceramic substrate according to any one of claims 32 to 35, characterized in that the side surface of the first recess is configured in a circular shape in a plan view, the side surface of the hole is configured in a circular shape in a plan view, and the difference between the diameter of the first recess and the diameter of the hole is 0.01 mm to 1 mm.

40. The high-temperature co-fired ceramic substrate according to any one of claims 32 to 35, characterized in that the high-temperature co-fired ceramic substrate has a circuit formation region, and the first recess and the hole are located outside the circuit formation region.

41. A space transformer substrate characterized by comprising a low-temperature co-firing ceramic substrate as described in any one of claims 23 to 26.

42. A space transformer substrate characterized by comprising a high-temperature co-firing ceramic substrate as described in any one of claims 32 to 35.

43. A probe card comprising a probe card body and a space transformer substrate as described in claim 41, wherein the space transformer substrate is fixed to the probe card body by inserting a mechanical fastening jig through the hole.

44. A probe card comprising a probe card body and a space transformer substrate as described in claim 42, wherein the space transformer substrate is fixed to the probe card body by inserting a mechanical fastening jig through the hole.

45. The probe card according to claim 43, wherein the mechanical fastening jig has a shaft portion and a large-diameter portion having a larger diameter than the shaft portion, and at least a portion of the large-diameter portion is in contact with the first main surface.

46. ​​The probe card according to claim 45, characterized in that it has a space between the shaft portion of the mechanical fastening jig and the side surface of the first recess.

47. The probe card according to claim 44, wherein the mechanical fastening jig has a shaft portion and a large-diameter portion having a larger diameter than the shaft portion, and at least a portion of the large-diameter portion is in contact with the first main surface.

48. The probe card according to claim 47, characterized in that it has a space between the shaft portion of the mechanical fastening jig and the side surface of the first recess.

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