High strength hybrid space transformer

Abstract

A high-strength hybrid space deformer is disclosed. The disclosed high-strength hybrid space deformer is a space deformer of a probe card placed between a pogo block for equipment and a wafer for testing to electrically connect a tester and a wafer for testing to inspect the electrical characteristics of chips on the wafer for testing. It comprises a sub-substrate including a plurality of metal posts for electrically contacting a plurality of pogo pins of the pogo block for equipment during testing, a multilayer ceramic substrate located below the sub-substrate and having metal patterns formed in multiple layers, and a plurality of probe pins connected to the lower part of the multilayer ceramic substrate and, during testing, contacting pads on the wafer for testing and inputting through the pogo pins to apply an electrical signal transmitted sequentially via the metal posts and the metal patterns of the multilayer ceramic substrate to the wafer for testing. By doing so, it has the effect of solving the problem of deformation of the space deformer caused by the load from a large number of probe pins in DRAM or HBM, and the problem of test failure resulting therefrom.

Description

Technology Field

[0001] The present invention relates to a space deformer for a probe card, and specifically to a high-strength hybrid space deformer that does not deform even under loads applied from probe pins and pogo pins of a test head. Background Technology

[0003] A probe card is a device necessary to electrically connect a test facility (hereinafter abbreviated as "tester") to a chip on a wafer in the wafer state, allowing the tester to inspect the electrical characteristics of the chip on the wafer. It basically includes a space transducer and probe pins. The probe pins are attached to a circuit board of a specific standard. The state of the chip is verified by the probe pins coming into contact with pads inside the chip on the wafer, the signal sent from the tester being transmitted to the chip, and the signal output from the chip being transmitted back to the tester. Depending on the pad arrangement of the chip to be tested or the arrangement of chips on the wafer, a probe card suitable for it is required. In particular, for DRAM or High Bandwidth Memory (HBM), compared to probe cards for non-memory or NAND, a relatively shorter test time and a larger number of probe pins with a narrow pitch are required to improve productivity.

[0004] In a probe card, the space transformer (STF) is known as a core device that serves as a test medium for inspecting semiconductor device performance in the wafer state, connecting micrometer-sized measurement pads on the wafer to test equipment. As shown in FIG. 1, the space transformer (12, 13) has a probe pin (13) connected to one side (probe side) and a pogo pin (14) connected to the pogo block (11) for the test equipment on the opposite side (LGA side), and it serves to transmit and receive test signals to and from the tester side through electrical contact with the pad (23) on the wafer (22) fixed by the chuck (21). While probe cards for NAND or flash memory have tens of thousands of probe pins, wafers for manufacturing ultra-high-density semiconductor memory such as DRAM and HBM have hundreds of thousands of probe pins; therefore, in the latter case, rigidity is required to withstand the load from a particularly large number of probe pins with minimal deformation. Therefore, for this purpose, a ceramic substrate is mainly used for the space transducer rather than an organic material-based PCB substrate, and the space transducer serves to spatially expand the narrow pad pitch of tens of micrometers present on the chips on the wafer and connect it to pads on the upper surface of hundreds of micrometers to tens of millimeters. The interior of the ceramic space transducer has hundreds of thousands to millions of vias connected to multiple internal layers (several to tens of layers), so reference numeral 12 in FIG. 1 is also referred to as MLC (Multi-Layer Ceramic).For example, in the case of a space transformer used for testing 300mm wafers, the thickness is generally set to about 2 to 8mm. However, as mentioned above, in the case of high-performance, high-density memory such as DRAM or HBM, there is a problem where the ceramic space transformer undergoes significant deformation due to the load applied to the LGA surface where the pogo pins contact as well as the hundreds of thousands of probe pins. The space transformer is manufactured in a way that secures height by making the thickness of the space transformer thicker, or by extending each of the pads for electrical contact located on the opposite side of the space transformer where the probe pins exist—that is, the pads of the space transformer that are contacted by the pogo pins on the side of the equipment pogo block (11)—by stacking multiple layers of a highly conductive metal, thereby obtaining a substantial thickness expansion effect of the ceramic space transformer.

[0005] However, the aforementioned conventional technologies designed to address the problem of deformation of the space transducer due to the load caused by the large number of probe pins required for testing DRAM or HBM not only fail to fundamentally resolve the deformation issue but also incur high costs due to additional required processes and cause another defect in the form of poor electrical contact between the metal layer stacked on top of the space transducer pads and the pogo pins. Therefore, there is an urgent need for the development of a new type of space transducer capable of solving these various problems, as well as a probe card including such a space transducer. Prior art literature

[0007] Republic of Korea Registered Patent No. 10-0907864 (Registered July 8, 2009) Republic of Korea Registered Patent No. 10-1050231 (Registered July 12, 2011) Republic of Korea Registered Patent No. 10-0951344 (Registered March 30, 2010) Republic of Korea Published Patent No. 10-2016-0095392 (Published February 3, 2015) The problem to be solved

[0008] The problem that the present invention aims to solve is to provide a high-strength hybrid space transformer capable of solving the problem of deformation of the space transformer due to the load applied to the LGA surface where a relatively large number (more than 100,000) of probe pins and pogo pins come into contact. means of solving the problem

[0010] A high-strength hybrid space deformer according to one aspect of the present invention for solving the above problem is a space deformer of a probe card disposed between a pogo block for equipment and a wafer for testing to electrically connect a tester and a wafer for testing to inspect the electrical characteristics of chips on the wafer for testing, comprising: a sub-substrate including a plurality of metal posts for electrically contacting a plurality of pogo pins of the pogo block for equipment during testing; a multilayer ceramic substrate located below the sub-substrate and having metal patterns formed in multiple layers; and a plurality of probe pins connected to the lower part of the multilayer ceramic substrate and, during testing, contacting pads on the wafer for testing and inputting through the pogo pins to apply an electrical signal to the wafer for testing, which is transmitted sequentially via the metal posts and the metal patterns of the multilayer ceramic substrate.

[0011] According to one embodiment, the multilayer ceramic substrate further comprises first pads formed on the upper surface of the multilayer ceramic substrate corresponding to the metal patterns of the multilayer ceramic substrate and located at the lower portion of each of the metal posts.

[0012] According to one embodiment, the metal posts may be formed from a metal having good conductivity, high physical strength, and high heat resistance, such as copper (Cu) plated with nickel (Ni) or gold (Au), silver (Ag) plated with nickel or gold, a nickel-cobalt alloy, a nickel-cobalt-rhodium alloy, and a nickel-cobalt-palladium alloy, and the first pads are formed from a combination of nickel (Ni) and gold (Au).

[0013] According to one embodiment, the sub-substrate further includes second pads formed on the upper surface of the sub-substrate to correspond to each of the metal posts.

[0014] According to one embodiment, the metal posts may be formed from a metal having good conductivity, high physical strength, and high heat resistance, such as copper (Cu) plated with nickel (Ni) or gold (Au), silver (Ag) plated with nickel or gold, a nickel-cobalt alloy, a nickel-cobalt-rhodium alloy, and a nickel-cobalt-palladium alloy, and the second pads are a combination of nickel (Ni) and gold (Au).

[0015] According to one embodiment, the sub-substrate and the multilayer ceramic substrate may be formed of the same material and have the same thickness.

[0016] According to one embodiment, the sub-substrate comprises metal post insertion holes formed to be relatively larger than the diameter of the metal posts for insertion of each of the metal posts, and a hole filler filled to prevent movement of the metal posts when each of the metal posts is inserted into each of the metal post insertion holes.

[0017] According to one embodiment, the hole filler may be a high-strength epoxy, such as a liquid-type ceramic or resin, which has high insulation and strength.

[0018] According to one embodiment, a fixing member penetrating the sub-substrate is further included to fix the sub-substrate and the multilayer ceramic substrate.

[0019] According to one embodiment, the space transformer further includes additional circuit components mounted on the upper or lower surface of the sub-substrate for operation, and the additional circuit components may be one or more of a resistor element, a capacitor element, an inductor element, and a relay element.

[0020] According to one embodiment, the multilayer ceramic substrate further includes an interlayer bonding material positioned between the sub-substrate and the multilayer ceramic substrate to maintain the sub-substrate on top of the multilayer ceramic substrate.

[0021] According to one embodiment, the interlayer bonding material may be a high-strength epoxy or glass green sheet. The material used for bonding between ceramics must basically have good high strength, heat resistance, and insulation properties.

[0022] A method for manufacturing a space deformer according to one aspect of the present invention for solving the above problem is a method for manufacturing a space deformer of a probe card disposed between a pogo block for equipment and a wafer to be tested for electrically connecting a tester and a wafer to be tested to test electrical characteristics of chips on the wafer to be tested, comprising: (a) preparing a multilayer ceramic substrate having metal patterns formed in multiple layers, a plurality of probe pins connected to the lower portion, and first pads formed on the upper surface corresponding to the metal patterns; (b) forming a plurality of metal posts above the first pads corresponding to each of the first pads on the multilayer ceramic substrate; (c) preparing a sub-substrate having metal post insertion holes formed at positions corresponding to each of the metal posts so that each of the metal posts can be inserted; (d) placing the sub-substrate on the upper portion of the multilayer ceramic substrate so that each of the metal posts is inserted into each of the metal post insertion holes; (e) flattening the upper surface of the sub-substrate by removing the protruding portions of the metal posts protruding above the sub-substrate; and (f) includes the step of forming a second pad on the upper portion of the metal posts from which the protrusions are removed from the upper surface of the flattened sub-substrate.

[0023] According to one embodiment, between step (d) and step (e), or between step (e) and step (f), the method further includes a step of filling a hole filler to prevent flow of the metal posts.

[0024] According to one embodiment, between step (c) and step (d), or between step (d) and step (e), the method further includes the step of placing an interlayer bonding material between the sub-substrate and the multilayer ceramic substrate to maintain the sub-substrate on top of the multilayer ceramic substrate. Effects of the invention

[0026] The present invention provides a high-strength hybrid space deformer, thereby effectively solving the problem of deformation of the space deformer caused by the load applied to the LGA surface where a large number of probe pins and pogo pins come into contact in DRAM or HBM. It should be noted that the effects of the present invention are further described in the following section titled 'Specific details for implementing the invention'. Brief explanation of the drawing

[0028] FIG. 1 is a drawing for illustrating a probe card including a conventional general ceramic space transformer, and FIG. 2 is a schematic diagram of a high-strength hybrid space transformer according to one embodiment of the present invention, and FIG. 3 is a schematic diagram of a high-strength hybrid space transformer according to another embodiment of the present invention, and FIG. 4 is a schematic diagram of a high-strength hybrid space transformer according to another embodiment of the present invention, and FIG. 5 is a schematic diagram of a high-strength hybrid space transformer according to another embodiment of the present invention, and FIGS. 6a to 6g are drawings for explaining a method for manufacturing a high-strength hybrid space transformer according to an embodiment of the present invention, and FIGS. 7a to 7e are drawings illustrating a method for manufacturing a high-strength hybrid space transformer according to another embodiment of the present invention. Specific details for implementing the invention

[0029] Preferred embodiments of the present invention are described below with reference to the attached drawings. It should be noted that the attached drawings and the embodiments described with reference thereto are simplified and illustrative for the purpose of assisting those skilled in the art in understanding the present invention. Additionally, it should be noted that the terms "contact" and "electrical contact" are used interchangeably in this specification, both of which refer to electrical connections between relevant components for applying a test signal. Furthermore, it should be noted that substantially identical components in the drawings are given the same reference numerals.

[0030] FIG. 2 is a schematic diagram of a high-strength hybrid space transformer according to one embodiment of the present invention, FIG. 3 is a schematic diagram of a high-strength hybrid space transformer according to another embodiment of the present invention, FIG. 4 is a schematic diagram of a high-strength hybrid space transformer according to yet another embodiment of the present invention, FIG. 5 is a schematic diagram of a high-strength hybrid space transformer according to yet another embodiment of the present invention, FIG. 6a to 6g are drawings for explaining a method of manufacturing a high-strength hybrid space transformer according to one embodiment of the present invention, and FIG. 7a to 7e are drawings for explaining a method of manufacturing a high-strength hybrid space transformer according to another embodiment of the present invention. As described above, the space transformer of the probe card of the present invention is a device disposed between a pogo block for equipment and a wafer to be tested in order to electrically connect a tester and a wafer to be tested to inspect the electrical characteristics of chips on the wafer to be tested.

[0031] First, FIG. 2 illustrates a basic form of a high-strength hybrid space deformer according to one embodiment of the present invention. In FIG. 2, reference numeral 11 represents a pogo block for equipment and reference numeral 14 represents pogo pins. Through the pogo pins (14) provided in the pogo block (11) for equipment, an electrical signal is applied from the tester (not shown) side to the wafer (22) to be tested, and the result is measured. Reference numeral 21 represents a chuck and reference numeral 23 represents pads on the wafer (22) to be tested.

[0032] Referring to FIG. 2, the high-strength hybrid space deformer of the present invention includes a sub-substrate (110), a multilayer ceramic substrate (120), and a plurality of probe pins (130).

[0033] The sub-substrate (110) includes a plurality of metal posts (111a) for electrically contacting a plurality of pogo pins (14) of a pogo block (11) for testing. The metal posts (111a) may be formed of a metal that has good conductivity, high physical strength, and high heat resistance, such as copper (Cu) or silver (Ag). The metal posts (111a) may also be formed from any one of the following: copper (Cu) plated with nickel (Ni) or gold (Au) (i.e., the body is made of copper material and its surface is plated with nickel or gold), silver (Ag) plated with nickel or gold (i.e., the body is made of silver material and its surface is plated with nickel or gold), a nickel-cobalt alloy (made of nickel and cobalt), a nickel-cobalt-rhodium alloy (made of nickel, cobalt, and rhodium), and a nickel-cobalt-palladium alloy (made of nickel, cobalt, and palladium). It is preferable that the bonding of the metal posts (111a) formed on the upper surface of the sub-substrate (110) be done by applying a high-temperature paste rather than general lead-free solder bonding. This is because, when bonding between ceramics, a temperature of about 400°C to 500°C is applied, so there should be no effect resulting from this. The above temperature range may vary depending on the melting point of the glass green sheet, the curing temperature of high-strength ceramic epoxy, etc.

[0034] The multilayer ceramic substrate (120) is located below the sub-substrate (110) and includes multilayer metal patterns. As previously mentioned, compared to conventional organic material-based PCB substrates, it serves to spatially expand the narrow pad locations of tens of micrometers present on the chips on the test wafer (22) and connect them to the upper side of the multilayer ceramic substrate (120), which is hundreds of micrometers to tens of millimeters in size. Although it is illustrated as having 5 layers in the drawing, as many as tens of layers of internal layers are provided, and the layers are electrically connected to each other through hundreds of thousands to millions of vias.

[0035] A plurality of probe pins (130) are connected to the lower part of a multilayer ceramic substrate (120) and are components for testing the characteristics of the wafer (22) by applying electrical signals to the wafer (22) during testing, which are input through a pogo pin (14) on the pogo block (11) side of the equipment and transmitted sequentially through the metal posts (111a) and the metal patterns of the multilayer ceramic substrate. That is, a plurality of probe pins (130) are components that are in direct contact with the wafer (22) during testing.

[0036] The sub-substrate (110) and the multilayer ceramic substrate (120) are formed from the same material and can be formed with generally the same thickness, but the sub-substrate may be thicker or thinner to match the overall thickness considering the spacing of the tester. In this way, the high-strength hybrid space deformer of the present invention is manufactured to have a relatively thicker thickness compared to the case where only a single ceramic substrate (12 in FIG. 1) is used as shown in FIG. 1 (for example, when the thickness of the sub-substrate (110) and the multilayer ceramic substrate (120) is the same, the thickness is twice that of the conventional one), thereby solving the problem of significant deformation of the ceramic space deformer caused by the load applied to the LGA surface where hundreds of thousands of probe pins and the pogo pins of the test head come into contact in the case of high-performance high-density memory such as DRAM or HBM.

[0037] Referring to FIG. 3, a high-strength hybrid space transformer according to one embodiment of the present invention comprises a sub-substrate (110), a multilayer ceramic substrate (120), and a plurality of probe pins (130), and further comprises additional circuit components (113) mounted on the upper or lower surface of the sub-substrate (110). The additional circuit components (113) are components for smooth operation of the space transformer and may be one or more of a resistor element, a capacitor element, an inductor element, and a relay element, but are not limited to these elements. The additional circuit components (113) may be mounted in a recessed manner so that their upper ends align with the upper or lower surface of the sub-substrate (110). Additionally, the high-strength hybrid space transformer of this embodiment further comprises a fixing member (112) that is fastened by penetrating the sub-substrate (110) to stably fix the sub-substrate (110) and the multilayer ceramic substrate (120). The basic configuration of the sub-substrate (110), the multilayer ceramic substrate (120), and the probe pins (130) is common to the embodiment of FIG. 2, so a redundant description of these common details is omitted.

[0038] In the embodiment of FIG. 3, the sub-substrate (110) includes metal post insertion holes (h1; see FIG. 6c) for inserting each of the metal posts (111a). To ensure that the metal posts (111a) can be inserted smoothly, the diameter of the metal post insertion holes (h1) is formed to be relatively larger than the diameter of the metal posts (111a). Then, a hole filler (111b) is filled to prevent movement of the metal posts (111a) when each of the metal posts (111a) is inserted into each of the metal post insertion holes (h1). The hole filler (111b) is generally a high-strength epoxy in the range of 150°C to 200°C, and more preferably, a high-strength epoxy in the range of 200°C to 250°C may be used for more stable maintenance. For example, the high-strength epoxy may be a liquid-type ceramic or resin with high insulation and strength.

[0039] Next, a high-strength hybrid space deformer according to another embodiment of the present invention will be described with reference to FIG. 4. As with FIG. 3, the basic configuration of the sub-substrate (110), multilayer ceramic substrate (120), and probe pins (130) in this example is common to the embodiment of FIG. 2, so a redundant description regarding these common details will be omitted.

[0040] In this embodiment, the high-strength hybrid space transformer includes first pads (P1). The first pads (P1) are formed on the upper surface of the multilayer ceramic substrate (120) to correspond to the metal patterns of the multilayer ceramic substrate (120) and are located below each of the metal posts (111a). The metal posts (111a) can be formed from a metal that has good conductivity, high physical strength, and strong heat resistance, such as copper (Cu) or silver (Ag). It is preferable to bond the metal posts (111a) formed on the upper surface of the sub-substrate (110) using a high-temperature paste rather than general lead-free solder bonding. This is because a temperature of approximately 4000°C to 5000°C is applied during bonding between ceramics, so there should be no adverse effects. The first pads (P1) are formed from a combination of nickel (Ni) and gold (Au). The first pads (P1) may be formed by methods such as sputtering or electroplating, but are not limited to these methods. Additionally, the high-strength hybrid space deformer includes second pads (P2). The second pads (P2) are formed on the upper surface of the sub-substrate (110) to correspond to each of the metal posts (111a). They are components for protecting the upper surface of the metal posts (111a), that is, the upper end of the metal posts (111a) exposed on the upper surface of the sub-substrate (110), and for increasing the contact efficiency with the pogo pin (14). The second pads (P2) may be formed from a combination of nickel (N1) and gold (Au), and may be formed by methods such as sputtering or electroplating, but are not limited to these methods. The second pads (P2) can be formed in such a way that they extend not only to the area directly above the top of each of the metal posts (111a) but also to the adjacent area, thereby further forming an area (CP) for contact of the pogo pin (14). Additionally, as shown in FIG. 4, the fixing member (112a, 112b; collectively 112) can be composed of a bolt (112a) and a nut (112b).A bolt (112a) penetrates the sub-substrate (110), and a nut (112b) is fixed to the upper part of the multilayer ceramic substrate (120). By using the bolt (112a) penetrating the sub-substrate (110) to the nut (112b) fixed to the upper part of the multilayer ceramic substrate (120), the sub-substrate (110) can be stably bonded to the upper part of the multilayer ceramic substrate (120). In addition, to ensure that the multilayer ceramic substrate (120) and the sub-substrate (110) are bonded and stably maintained, an interlayer bonding material (115) may be further filled between the multilayer ceramic substrate (120) and the sub-substrate (110). Similar to the hole filling material (111b) described above, a high-strength epoxy with a temperature range of 150°C to 200°C or a high-strength epoxy with a temperature range of 200°C to 250°C may be used as the interlayer bonding material (115). Alternatively, a glass green sheet may be used as an interlayer bonding material (115). Here, the glass green sheet is a material having a melting point of about 400°C, which is sandwiched between two ceramic substrates, namely a sub-substrate (110) and a multilayer ceramic substrate (120), and heated in that state so that the glass softens and consequently chemically bonds with the ceramic. The interlayer bonding material (115) is basically intended to bond two ceramic layers, and basically, it needs to have good high strength, heat resistance, and insulation properties.

[0041] Next, a high-strength hybrid space deformer according to another embodiment of the present invention will be described with reference to FIG. 5. As with FIG. 3, the basic configuration of the sub-substrate (110), multilayer ceramic substrate (120), and probe pins (130) in this example is common to the embodiment of FIG. 2, so a redundant description regarding these common details will be omitted.

[0042] In this embodiment, pad insertion holes (116) are formed at the bottom of the metal post insertion holes (h1; FIG. 6c) for inserting the first pad (P1), and are larger than the diameter of the metal post insertion holes (h1) and larger than the footprint of the first pad (P1). Therefore, in this case, unlike in the embodiment of FIG. 4, the use of an interlayer bonding material (115) may be omitted. In addition, in the embodiment of FIG. 5, a nut insertion hole (117) may be further formed in the sub-substrate (110). By doing so, when the sub-substrate (110) is bonded to the upper part of the multilayer ceramic substrate (120), it can be bonded stably while maintaining a horizontal position.

[0043] Next, a method for manufacturing a high-strength hybrid space transformer according to an embodiment of the present invention will be described with reference to FIGS. 6a to 6g. The method for manufacturing a high-strength hybrid space transformer according to an embodiment of the present invention comprises the following steps.

[0044] First, as shown in FIG. 6a, a multilayer ceramic substrate (120) is prepared in which metal patterns are formed in multiple layers, a plurality of probe pins are connected to the lower part, and first pads (P1) are formed on the upper surface corresponding to the metal patterns.

[0045] Then, as shown in FIG. 6b, a plurality of metal posts (111a) are formed above the first pads (P1) on the multilayer ceramic substrate (120) corresponding to each of the first pads (P1). Each of the first pads (P1) is electrically connected only to its respective corresponding metal post (111a) and is formed to be electrically insulated from one another.

[0046] Then, as illustrated in FIG. 6c, a sub-substrate (110) is prepared in which metal post insertion holes (h1) are formed at corresponding positions of each metal post (111a) to allow insertion of each metal post (111a). The preparation of this sub-substrate (110) may be carried out in parallel with another process while forming the metal posts (111a) on the multilayer ceramic substrate (120), or it may be carried out prior to the step of forming the metal posts (111a) on the multilayer ceramic substrate (120). As previously described, the multilayer ceramic substrate (120) and the sub-substrate (110) may be formed of the same material, and the thickness (T1) of the multilayer ceramic substrate (120) and the thickness (T1) of the sub-substrate (110) may be the same.

[0047] Then, as illustrated in FIGS. 6C and 6D, a sub-substrate (110) is placed on top of a multilayer ceramic substrate (120) such that each of the metal posts (111a) is inserted into each of the metal post insertion holes (h1). FIG. 6D shows the state in which the sub-substrate (110) is coupled to the top of the multilayer ceramic substrate (120). In this process, the sub-substrate (110) may be secured by a fixing member equipped with a bolt (112a) and a nut (112b) so that it can be more stably fixed to the multilayer ceramic substrate (120). In this coupled state, the upper portions of the metal posts (111a) protrude above the upper portion of the sub-substrate (110) (outside the upper surface).

[0048] As illustrated in FIG. 6e, the upper surface of the sub-substrate (110) is flattened by removing the protruding portions of the metal posts (111a) that protrude above the sub-substrate (110). The removal of the protruding portions of the metal posts (111a) may be performed by chemical mechanical planarization (CMP), but is not limited to this method.

[0049] FIG. 6f shows a state in which a hole filler (111b) is filled to prevent movement of the metal posts (111a) and to keep them stable. The filling of the hole filler (111b) may be performed before or after removing the protruding portions of the metal posts (111a).

[0050] Then, as illustrated in FIG. 6g, a second pad (P2) is formed on the upper surface of the metal posts (111a) from which the protrusions have been removed on the upper surface of the flattened sub-substrate (110). To prevent oxidation caused by the exposure of the upper portions of the metal posts (111a) and to increase the contact efficiency with the pogo pins, the second pad (P2) is formed, for example, with a combination of nickel (Ni) and gold (Au). The second pad (P2) may be formed by sputtering or electroplating, but is not limited to these methods. Additionally, as previously mentioned, the second pad (P2) may be formed in such a way that it extends not only to the area directly above the upper portion of each metal post (111a) but also to the adjacent area, thereby further forming an area (CP) for contact with the pogo pins (14).

[0051] Finally, a method for manufacturing a high-strength hybrid space transformer according to another embodiment of the present invention will be described with reference to FIGS. 7a to 7e.

[0052] As illustrated in FIG. 7a, a multilayer ceramic substrate (120) is prepared in which a plurality of metal posts (111a) are formed above the first pads (P1) corresponding to each of the first pads (P1) formed to correspond to the metal patterns. In this embodiment, the step of placing an interlayer bonding material (115) between the sub-substrate (110) and the multilayer ceramic substrate (120) is further included to support the sub-substrate (110) on top of the multilayer ceramic substrate (120). The placement of the interlayer bonding material (115) may be performed before bonding the sub-substrate (110) on top of the multilayer ceramic substrate (120). As previously mentioned, since the interlayer bonding material (115) is intended to bond two layers of ceramic, it must have good high strength, heat resistance, and insulation properties. For example, high-strength epoxy or glass green sheets may be used.

[0053] Next, as illustrated in FIG. 7b, a sub-substrate (110) is prepared in which metal post insertion holes (h3) are formed at corresponding positions of each metal post (111a) to allow insertion of each metal post (111a). Likewise, the preparation of this sub-substrate (110) may be carried out in parallel with another process while forming the metal posts (111a) on the multilayer ceramic substrate (120), or may be carried out prior to the step of forming the metal posts (111a) on the multilayer ceramic substrate (120).

[0054] Then, as illustrated in FIGS. 7b and 7c, a sub-substrate (110) is placed on top of a multilayer ceramic substrate (120) such that each of the metal posts (111a) is inserted into each of the metal post insertion holes (h3). FIG. 7c shows the state in which the sub-substrate (110) is coupled to the top of the multilayer ceramic substrate (120). In this process, the sub-substrate (110) may be secured by a fixing member equipped with a bolt (112a) and a nut (112b) so that it can be more stably fixed to the multilayer ceramic substrate (120). In this coupled state, the upper portions of the metal posts (111a) protrude above the upper portion (outside the upper surface) of the sub-substrate (110).

[0055] Then, as illustrated in FIG. 7d, the upper surface of the sub-substrate (110) is flattened by removing the protrusions of the metal posts (111a) that protrude above the sub-substrate (110). The removal of the protrusions of the metal posts (111a) may be carried out by chemical mechanical planarization (CMP), but is not limited to this method. Additionally, as further illustrated in FIG. 7d, a hole filler (111b) is filled to prevent the metal posts (111a) from flowing and to ensure they remain stable. The filling of the hole filler (111b) may be carried out before or after removing the protrusions of the metal posts (111a). For structural stability, it is preferable to remove the protrusions of the metal posts (111a) through chemical mechanical planarization (CMP) after the hole filler (111b) and curing have been carried out (i.e., after physical fixation) prior to removing the protrusions of the metal posts (111a). This is because if the protrusion is removed immediately without doing so, there is a risk that the post may be damaged.

[0056] Then, as illustrated in FIG. 7e, a second pad (P2) is formed on the upper surface of the metal posts (111a) from which the protrusions have been removed on the upper surface of the flattened sub-substrate (110). To prevent oxidation caused by the exposure of the upper portions of the metal posts (111a) and to increase the contact efficiency with the pogo pins, the second pad (P2) is formed, for example, with a combination of nickel (Ni) and gold (Au). The second pad (P2) may be formed by sputtering or electroplating, but is not limited to these methods. Likewise, the second pad (P2) may be formed in such a way that it extends not only to the area directly above the upper portion of each of the metal posts (111a) but also to the adjacent area, thereby further forming an area (CP) for contact with the pogo pins (14).

[0057] As described above, the high-strength hybrid space deformer of the present invention can effectively solve the problem of deformation caused by the load applied to the LGA surface where a large number of probe pins and the pogo pins of the test head come into contact, and the resulting test failure problem, by using a sub-substrate and appropriately combining it with a multilayer ceramic substrate. Explanation of the symbols

[0059] 110: Sub-substrate 111a : Metal post 111b: Hole filler 115 : Interlayer bonding material 120: Multilayer ceramic substrate 130 : Probe pin

Claims

Claim 1 A space deformer of a probe card disposed between a pogo block for equipment and a wafer for testing to electrically connect a tester and a wafer for testing to examine the electrical characteristics of chips on the wafer for testing, comprising: a plurality of metal posts for electrically contacting the pogo pins to reduce deformation of the multilayer ceramic substrate (120) caused by loads applied from a plurality of pogo pins of the pogo block for equipment and probe pins to the pogo pins during testing; metal post insertion holes formed relatively larger than the diameter of the metal posts for inserting each of the metal posts; and a hole filler filled to prevent movement of the metal posts when each of the metal posts is inserted into each of the metal post insertion holes, wherein the metal posts are bonded to the upper side of the multilayer ceramic substrate before being inserted into the metal post insertion holes; a multilayer ceramic substrate (120) located at the lower side of the sub-substrate and having metal patterns formed in multiple layers; and connected to the lower side of the multilayer ceramic substrate and, during testing, contacting pads on the wafer for testing, and the pogo A space transformer characterized by comprising: a plurality of probe pins (130) for applying an electrical signal to the test target wafer side, which is input through the pins and transmitted sequentially via the metal posts and the metal patterns of the multilayer ceramic substrate; first pads formed on the upper surface of the multilayer ceramic substrate corresponding to the metal patterns of the multilayer ceramic substrate and located below each of the metal posts; second pads formed on the upper surface of the sub-substrate corresponding to each of the metal posts; and a fixing member fastened by penetrating the sub-substrate to fix the sub-substrate and the multilayer ceramic substrate. Claim 2 delete Claim 3 A space transformer according to claim 1, wherein the metal posts are formed from any one of copper (Cu) plated with nickel (Ni) or gold (Au), silver (Ag) plated with nickel or gold, a nickel-cobalt alloy, a nickel-cobalt-rhodium alloy, and a nickel-cobalt-palladium alloy, and the first pads are formed from a combination of nickel (Ni) and gold (Au). Claim 4 delete Claim 5 A space transformer according to claim 1, wherein the metal posts are formed from any one of copper (Cu) plated with nickel (Ni) or gold (Au), silver (Ag) plated with nickel or gold, a nickel-cobalt alloy, a nickel-cobalt-rhodium alloy, and a nickel-cobalt-palladium alloy, and the second pads are formed from a combination of nickel (Ni) and gold (Au). Claim 6 A space transformer according to claim 1, wherein the sub-substrate and the multilayer ceramic substrate are formed of the same material and have the same thickness. Claim 7 A space transformer according to claim 1, wherein the sub-substrate comprises metal post insertion holes formed to be relatively larger than the diameter of the metal posts for insertion of each of the metal posts, and a hole filler filled to prevent movement of the metal posts when each of the metal posts is inserted into each of the metal post insertion holes. Claim 8 A space transformer according to claim 1, further comprising a fixing member penetrating the sub-substrate to fix the sub-substrate and the multilayer ceramic substrate. Claim 9 A space transformer according to claim 1, further comprising additional circuit components mounted on the upper or lower surface of the sub-substrate for operation of the space transformer, wherein the additional circuit components are one or more of a resistor element, a capacitor element, an inductor element, and a relay element. Claim 10 A space transformer according to claim 1, further comprising an interlayer bonding material positioned between the sub-substrate and the multilayer ceramic substrate to maintain the sub-substrate on the upper surface of the multilayer ceramic substrate. Claim 11 A method for manufacturing a space transformer of a probe card disposed between a pogo block for equipment and a wafer to test, for electrically connecting a tester and a wafer to test to inspect the electrical characteristics of chips on the wafer to test, comprising: (a) preparing a multilayer ceramic substrate having metal patterns formed in multiple layers, a plurality of probe pins connected to the lower portion, and first pads formed on the upper surface corresponding to the metal patterns; (b) forming a plurality of metal posts on the multilayer ceramic substrate above the first pads corresponding to each of the first pads; (c) preparing a sub-substrate having metal post insertion holes formed at positions corresponding to each of the metal posts so that each of the metal posts can be inserted; (d) placing the sub-substrate on the upper portion of the multilayer ceramic substrate so that each of the metal posts is inserted into each of the metal post insertion holes, and then fixing the sub-substrate and the multilayer ceramic substrate by penetrating the sub-substrate with a fixing member; (e) flattening the upper surface of the sub-substrate by removing the protruding portions of the metal posts protruding above the sub-substrate. and (f) forming a second pad on the upper portion of the metal posts from which the protrusions are removed from the upper surface of the flattened sub-substrate; characterized by a method for manufacturing a space transformer. Claim 12 A method for manufacturing a space transformer according to claim 11, further comprising the step of filling a hole filler to prevent flow of the metal posts between step (d) and step (e), or between step (e) and step (f). Claim 13 A method for manufacturing a space transformer according to claim 11, further comprising the step of placing an interlayer bonding material between the sub-substrate and the multilayer ceramic substrate to maintain the sub-substrate on top of the multilayer ceramic substrate between step (c) and step (d), or between step (d) and step (e).

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