JP5058041B2 - Contact probe manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a contact probe, and more particularly to a method for manufacturing a contact probe that can reduce stress concentration at a bent portion of a contact probe having a cantilever structure.

  A probe card used for inspecting electrical characteristics of an inspection object such as an electrode pad of a semiconductor integrated circuit includes a plurality of contact probes (contact probes). The plurality of contact probes are fixed on the substrate corresponding to the number and pitch of the electrode pads, and take out electrical signals by contacting the electrode pads.

  When inspecting the electrical characteristics of the device on the semiconductor wafer, the contact probe is brought into contact with the electrode pad on the semiconductor wafer, and then the overdrive is performed to further press the contact probe toward the semiconductor wafer. Each contact probe is securely brought into contact with the electrode pad.

  The contact probe has a beam part of an elastically deformable cantilever structure in which one end is fixed to the substrate and the other end is a free end, and a contact part formed on the free end side of the beam part. (See, for example, Patent Document 1). Such a contact probe is generally arranged in a state where the beam portion extends in parallel with the main surface of the substrate, and a portion bent at a substantially right angle is formed on the fixed end side of the beam portion. In this type of contact probe, when the contact portion is pressed against the semiconductor wafer, the beam portion is elastically deformed.

  By the way, semiconductor devices have been highly integrated due to a significant improvement in microfabrication accuracy due to advances in photolithography technology and the like. As a result, the number of electrode pads with respect to the chip area of a semiconductor device has increased dramatically. Recently, more than 1,000 electrode pads have been arranged on a semiconductor chip of several millimeters square at a narrow pitch. . In order to perform an electrical characteristic test on such a semiconductor chip, a probe card in which contact probes are arranged at the same pitch as the electrode pads is required. Therefore, as disclosed in Patent Document 1 described above, various techniques for manufacturing a contact probe using a photolithography technique similar to that of a semiconductor device have been proposed.

Patent Document 1 discloses a contact probe made of a laminate formed using a so-called MEMS (Micro Electro Mechanical Systems) technique. This contact probe is composed of a plurality of layers formed in a two-dimensional shape parallel to the probe substrate. Each of these layers is stacked in a direction perpendicular to the probe substrate, that is, in the height direction of the contact probe, under control by a photolithography technique, thereby forming a contact probe having a three-dimensional cantilever structure.
7 (A) to 10 (O) of Japanese Patent Laid-Open No. 2001-91539.

  However, when a contact probe is formed by laminating in the height direction, it has a bent portion that bends at a right angle on the fixed side of the beam portion. This bent portion tends to concentrate stress during elastic deformation, and the beam portion may be damaged. For this reason, the beam portion of the contact probe having a cantilever structure is preferably formed by, for example, bending a bent portion in an arc shape so as not to form a corner portion in order to reduce stress concentration.

  Further, when the contact probe having a bent portion on the fixed side of the beam portion as described above is elastically deformed by performing the overdrive, the bent portion comes into contact with the inspection object when the amount of overdrive increases. There was also a problem. When a sufficient overdrive amount cannot be obtained in this way, a sufficient pressing force for reliably bringing the contact probe into contact with the inspection object cannot be obtained.

  As a method of forming a contact probe having a curved portion using the MEMS technique, a method of stacking the contact probe from one end in the width direction to the other end of the beam portion can be considered. However, when the contact probes are stacked in the width direction, it is difficult to form a complicated shape in the width direction, and the interval corresponding to the position fixed to the probe substrate is maintained. A plurality of contact probes cannot be formed simultaneously. Therefore, for example, a plurality of contact probes cannot be arranged on the probe substrate together with the sacrificial layer, or the contact probes cannot be formed by electroplating the probe substrate. A troublesome work of fixing to the substrate is required.

  Therefore, the present applicant has found a method of manufacturing a contact probe that can form a curved portion in a beam portion in a manufacturing method of forming a contact probe by stacking in the height direction. In the manufacturing method, a probe forming pedestal having a curved surface is formed on a substrate with a resist, and a beam portion is formed on the probe forming pedestal. In this case, in order to form a probe-forming pedestal having a curved surface with a resist, first, a block-shaped pedestal having a corner is formed, and then the block-shaped pedestal is heated at a high temperature to shrink the corner. By forming a round shape, a curved surface is formed.

  However, since the pedestal formed of the resist is heat-treated at a high temperature, there is a problem that a substance in the resist material is volatilized or thermally contracted, and the desired height cannot be obtained on the pedestal. Therefore, as a result of further research, a thin film was formed on the resist pedestal after the heat treatment using a conductive material different from the conductive material forming the contact probe, and the same conductive material as the thin film was used on the thin film. A plating base with a desired height was obtained by electroplating.

  However, since the resist pedestal is formed inside this plating pedestal, the resist pedestal heat shrinks due to the temperature rise during probe manufacturing, and the metal thin film formed on the resist pedestal cracks. There was a problem that the plating base was damaged. Furthermore, since this resist pedestal is subjected to heat treatment at a temperature higher than the temperature used in normal resist processing to produce a curved surface, it is cured even if the resist layer is removed after the contact probe is formed. There was also a problem that it was too difficult to remove.

  The present invention has been made in view of the above circumstances. The present invention relates to a method for forming a contact probe by stacking in a height direction, and a desired shape and size without damaging the pedestal due to heat. An object of the present invention is to provide a method of manufacturing a contact probe that can easily form a contact probe having a plurality of curved portions in a stepwise manner.

  According to a first method of manufacturing a contact probe of the present invention, a first conductive film made of a conductive material is formed on an insulating substrate, and a first conductive film made of the first conductive film is formed on the main surface of the insulating substrate. A first conductive film forming step of forming a conductive region and an insulating region adjacent to the first conductive region; and electroplating a conductive material on the first conductive film, thereby forming the first conductive region A first sacrificial layer forming step of forming a first sacrificial layer having a base curved surface rising at a peripheral edge extending to the outside and bending toward the first conductive region; and adjacent to the first sacrificial layer and the first sacrificial layer A second conductive film made of a conductive material is formed on the exposed insulating region, and a second conductive region made of the second conductive film and a second conductive region are formed on the main surface of the insulating substrate. A second conductive film forming step for forming an adjacent insulating region; By electroplating a conductive material on the conductive film, a first curved surface that rises at the peripheral edge extending to the outside of the second conductive region and curves toward the second conductive region, and above the base curved surface A second sacrificial layer forming step of forming a second sacrificial layer formed and having a second curved surface rising toward the center from the end side of the second conductive film; and forming a contact probe on the second sacrificial layer A probe forming step and a sacrificial layer removing step of removing the first conductive film, the first sacrificial layer, the second conductive film, and the second sacrificial layer by etching the conductive material are provided. .

  In the contact probe manufacturing method of the present invention, the first sacrificial layer having the base curved surface is formed on the first conductive film using a conductive material, and the second conductive layer is formed on the first sacrificial layer. By forming a film and further forming a second sacrificial layer on the second conductive film, the first curved surface and the second curved surface for forming the curved portion of the contact probe without being damaged by heat are formed. The sacrificial layer can be easily formed. Then, by electroplating the sacrificial layer, it is possible to easily form the contact probe having a plurality of curved portions where stress concentration does not occur. Therefore, even when a contact probe is formed by laminating in the height direction by electroplating, a contact probe having a plurality of curved portions having a desired shape and size can be easily formed.

  That is, according to the contact probe manufacturing method of the present invention, the second conductive film is formed on the first sacrificial layer having the base curved surface and the insulating region exposed adjacent to the first sacrificial layer. Therefore, by electroplating the second conductive film, a conductive material is also deposited on the end surface of the second conductive film. As a result, a first curved surface that rises in the insulating region and bends toward the second conductive region, and is formed above the base curved surface and rises toward the center from the end side of the second conductive film. A second sacrificial layer having two curved surfaces can be easily formed. Then, by forming the contact probe on the second sacrificial layer along the first curved surface and the second curved surface, the contact probe having a plurality of curved portions can be easily formed.

  In addition, a stepped sacrificial layer having a plurality of curved surfaces can be formed in a desired size and shape by simply forming the first conductive film and the second conductive film in a desired shape and size. In addition, since all of the conductive material is formed, the sacrificial layer is not damaged even if the temperature rises during the manufacturing process.

  Further, since the position of the curved portion of the contact probe formed in this manner changes in a step shape from the position of the contact probe fixed to the insulating substrate toward the free end, the contact probe has a free position. Even if the end side is greatly overdriven, the fixed end side of the contact probe can be prevented from contacting the inspection object.

  In the contact probe manufacturing method according to the second aspect of the present invention, in the first conductive film forming step, the first conductive film is formed so as to form the first conductive region sandwiched between the insulating regions, In the sacrificial layer forming step, the first sacrificial layer is formed so as to have two opposing base curved surfaces.

  By forming the first sacrificial layer in this manner, the base curved surface can be simultaneously formed at two locations so as to face each other. Therefore, the first curved surface having the first curved surface and the second curved surface is formed on one first sacrificial layer. Two sacrificial layers can be formed, or one second sacrificial layer having two first curved surfaces and two second curved surfaces can be formed. A contact probe having a desired shape can be efficiently formed in accordance with the position of contact with the inspection object.

  According to a third method of manufacturing a contact probe according to the present invention, in the second conductive film forming step, a second conductive film is formed so as to form a second conductive region sandwiched between the insulating regions, In the sacrificial layer forming step, the second sacrificial layer is formed so as to have two first curved surfaces and two second curved surfaces facing each other.

  In the manufacturing method of the present invention, it is possible to form a pair of contact probes so that their free ends are opposed to each other by using a single second sacrificial layer having two first and second curved surfaces facing each other. Thus, a plurality of the contact probes can be efficiently formed on the substrate. In addition, when a plurality of contact probes are formed on one second sacrificial layer, a plurality of contact probes whose free ends are opposed to each other are separated from the insulating substrate together with the first and second sacrificial layers. It can peel and can arrange | position with the said sacrificial layer on the probe board prepared separately. By arranging the contact probes on the probe substrate in this way, a plurality of contact probes can be fixed at predetermined positions on the probe substrate while maintaining a predetermined interval.

  According to the method for manufacturing a contact probe according to the present invention, the contact probe having a plurality of curved portions is formed by a simple method even when the contact probes having a cantilever structure are stacked by electroplating in the height direction. be able to. And since the said contact probe can be formed so that it may have a some curved part in step shape, it can prevent that the said contact probe contacts a test object even with a big overdrive amount.

Embodiment 1.
Hereinafter, a first embodiment of a contact probe manufacturing method according to the present invention will be described with reference to the drawings.

[Probe device]
FIG. 1 is a diagram showing an example of a schematic configuration of a probe apparatus 100 including a probe card 110 according to an embodiment of the present invention, and shows an internal state of the probe apparatus 100. The probe device 100 includes a probe card 110, a movable stage 103 on which an inspection object 102 is placed, a driving device 104 that raises and lowers the movable stage 103, and a housing 105 that houses the movable stage 103 and the driving device 104. It consists of.

  The inspection object 102 includes a semiconductor device such as a semiconductor wafer, and a plurality of electronic circuits (not shown) are formed. The movable stage 103 is a mounting table having a horizontal mounting surface. When the driving device 104 is driven, the movable stage 103 is raised or lowered in the vertical direction in a state where the inspection object 102 is mounted on the mounting surface. ing. The housing 105 has an opening at the upper center portion, and the probe card 110 is attached so as to seal the opening. The movable stage 103 is disposed below the opening.

[Probe card]
FIGS. 2A and 2B are diagrams showing a configuration example of the probe card 110 in the probe apparatus 100 of FIG. 1, and FIG. 2A shows the inspection object 102 side (the lower side of FIG. 1). (B) in the figure is a side view.

  The probe card 110 includes a main board 106 attached to the opening of the housing 105, a rectangular probe board 107 held on the main board 106, and a plurality of contact probes 1 fixed on the probe board 107. .

  The main board 106 is a disk-shaped printed board, and has an external terminal 161 for performing signal input / output with the tester device. For example, a multilayer printed circuit board mainly composed of glass epoxy is used as the main board 106. The peripheral portion of the main substrate 106 is held horizontally by the peripheral edge of the opening of the housing 105 and is supported horizontally.

  The probe substrate 107 is disposed below the main substrate 106 and supported by the main substrate 106. Further, the probe board 107 is electrically connected to the connecting member 108, and the connecting member 108 is connected to the connector 162 of the main board 106. The probe substrate 107 has a rectangular shape smaller than the main substrate 106, and a wiring pattern is formed on the substrate. The wiring pattern is formed by wiring patterns of a power supply line, a ground line, and a signal line. When the inspection object 102 is made of a silicon wafer, the probe substrate 107 is preferably composed of a single crystal substrate such as silicon. In this way, by configuring the probe substrate 107 with a silicon substrate, the thermal expansion state between the probe substrate 107 and the inspection object 102 can be made closer.

  The connecting member 108 connects the main board 106 and the probe board 107 and conducts the wiring formed on the main board 106 and the probe board 107 as conductive lines. Here, a flexible printed circuit board (FPC) in which a wiring pattern is printed on a flexible film containing polyimide as a main component is used as the connecting member 108. One end of the flexible substrate is fixed to the peripheral portion of the probe substrate 107, and the other end is connected to the main substrate 106 via a detachable connector 162.

  In the present embodiment, a large number of electrode pads are formed on the probe substrate 107, and the contact probes 1 are bonded to the respective electrode pads, whereby a large number of contact probes 1 are formed on the probe substrate 107. As described above, the probe board 107 is electrically connected to the main board 106 connected to the tester device via the connecting member 108 and constitutes a probe card together with the main board 106. At the time of inspection, the movable stage 103 is raised by the driving device 104 and the contact probe 1 is brought into contact with the semiconductor wafer, so that signals are input / output between the tester device and the semiconductor wafer via each contact probe 1, Inspection of electrical characteristics of semiconductor wafers is performed.

〔Contact probe〕
As shown in FIGS. 1 and 2, the contact probe 1 is a probe (probe) that is elastically brought into contact with a fine electrode pad 121 formed on the inspection object 102. Each contact probe 1 is aligned and fixed on one main surface of the probe substrate 107. Each contact probe 1 is arranged so that the main surface of the probe substrate 107 to which each contact probe 1 is fixed faces downward in the vertical direction so as to face the inspection object 102 arranged on the movable stage 103. It has become.

  FIG. 3 is a side view of the contact probe 1. The contact probe 1 includes a contact portion 2 that makes contact with the electrode pad 121 on the inspection object 102, and a beam portion 3 that has one end fixed to the probe substrate 107 and the other end protruding from the contact portion 2. The

  The beam portion 3 is composed of a long plate-shaped member, and one end portion thereof is a cantilever beam (cantilever) fixed to the probe substrate 107. That is, the beam unit 3 is fixed to the probe substrate 107, and is fixed to the probe substrate 107. The beam unit 3 rises while being curved with respect to the probe substrate 107 and extends in parallel with the probe substrate 107. It is comprised from the elastic deformation part 32 which curves toward. The substrate fixing portion 31 is formed by a probe forming base film 6 which will be described later in part on the side facing the probe substrate 107.

  The beam portion 3 has a substrate fixing portion 31 as a fixed end, and the other end side of the elastic deformation portion 32 with respect to the fixed end is a free end. A load is applied to the free end of the elastic deformation portion 32 from the inspection object 102 side. Thus, the elastic deformation portion 32 is elastically deformed. In the present embodiment, the movable stage 103 is raised toward the probe card 110 and the free end portion of the beam portion 3 is pressed by the inspection object 102 so that the elastic deformation portion 32 of the beam portion 3 is elastically deformed. It has become.

  The contact portion 2 is configured by a contact chip formed so as to protrude on the surface of the free end portion of the beam portion 3 that faces the inspection object 102. This contact chip is formed of a columnar body having a pentagonal end surface. A surface of the contact portion 2 facing the inspection object 102 is a contact surface that contacts the electrode pad 121 of the inspection object 102.

  In the probe card 110 of the present embodiment, a plurality of contact probes 1 are arranged on the probe substrate 107 at a predetermined pitch in the beam width direction, and a row of contact probes 1 arranged at such a pitch is a beam tip. Are formed in two rows so as to face each other. In the present embodiment, a row of contact probes 1 is formed with a direction parallel to any one side of the rectangular probe substrate 107 as an arrangement direction. The interval between the contact probes 1 is determined according to the pitch between the electrode pads 121 formed on the inspection object 102.

  Each contact probe 1 is electrically connected to the external terminal 161 of the main board 106 via each wiring formed on the probe board 107, the connecting member 108, and the main board 106. By bringing the contact portion 2 of the contact probe 1 into contact with the minute electrode pad 121 of the inspection object 102, the inspection object 102 is brought into conduction with the tester device.

[Component materials of contact probe]
Next, the material of each component of the contact probe 1 will be described. Since the contact probe 1 is preferably as low as possible, each component of the contact probe needs to be made of a material having high conductivity. Examples of such highly conductive materials include silver (Ag), copper (Cu), gold-copper alloy (Au—Cu), nickel (Ni), palladium nickel alloy (Pd—Ni), nickel cobalt alloy (Ni—). Co), nickel tungsten (Ni-W), platinum (Pt), gold (Au), rhodium (Rh), and the like. In the present embodiment, since the second sacrificial layer 82 to be described later is formed of copper, the beam portion 3 of the contact probe 1 is preferably formed using a conductive material that is not dissolved by the copper etching solution. In the present embodiment, the beam portion 3 is formed using a nickel cobalt alloy.

  Further, since the contact portion 2 of the contact probe 1 is repeatedly brought into contact with the electrode pad 121 of the inspection object 102, high wear resistance is required, and each time the contact portion 2 is brought into contact, the surface of the electrode pad 121 is scratched. It is required to remove dust and oxide films on the surface. Therefore, examples of the conductive material used for forming the contact portion include a highly wear-resistant conductive material such as rhodium (Rh) and palladium cobalt alloy (Pd—Co). In the present embodiment, the contact portion 2 is formed using rhodium (Rh).

[Contact probe manufacturing process]
4 to 6 are views showing an example of a manufacturing process of the contact probe 1 shown in FIG. The contact probe 1 is manufactured using a so-called MEMS (Micro Electro Mechanical Systems) technique. The MEMS technique is a technique for creating a fine three-dimensional structure using a photolithography technique and a sacrificial layer etching technique. The photolithography technique is a fine pattern processing technique using a photosensitive resist used in a semiconductor manufacturing process or the like. The sacrificial layer etching technique is a technique for forming a three-dimensional structure by forming a lower layer called a sacrificial layer, further forming a layer constituting the structure thereon, and then etching only the sacrificial layer. is there.

  A well-known plating technique can be used for forming each layer including the sacrificial layer. For example, by immersing a substrate as a cathode and a metal piece as an anode in an electrolytic solution and applying a voltage between both electrodes, the metal ions in the electrolytic solution can be attached to the substrate surface. Such a process is called an electroplating process. Since such an electroplating process is a wet process in which the substrate is immersed in an electrolytic solution, a drying process is performed after the plating process. Further, after drying, a flattening process for flattening the laminated surface by a polishing process or the like is performed as necessary.

  4A to 4D show a conductive film forming process in which a conductive film is partially formed on the probe substrate 107 which is an insulating substrate. The conductive film forming step includes a step of forming the insulating film 4, a step of forming the first conductive film 51, and a step of forming the probe forming base film 6.

First, as shown in FIG. 4A, the insulating film 4 made of silicon dioxide (SiO ₂ ) is formed on the probe substrate 107. Further, a probe forming base film 6 is formed on the insulating film 4 using a conductive material other than copper (Cu) and insoluble in a copper plating solution. The insulating film 4 and the probe forming base film 6 are preferably formed by vacuum deposition such as sputtering.

  Examples of the conductive material for forming the probe forming base film 6 include nickel cobalt alloy (Ni—Co), palladium (Pd), platinum (Pt), rhodium (Rh), gold (Au), nickel (Ni Etc.) are preferred. In particular, by using the same material as that constituting the beam portion 3 of the contact probe 1, the probe forming base film 6 can be made a part of the contact probe 1.

  Although not shown, a photoresist layer made of a photosensitive organic material is further applied on the probe forming base film 6 to form a resist layer. Thereafter, the resist layer is partially removed by selectively exposing the surface of the resist layer.

  The portion from which the resist layer has been removed in this way is dry-etched with argon ions as shown in FIG. 4B, and the probe forming base film 6 excluding the portion where the resist layer remains is removed. Remove. Then, by completely removing the resist layer, the probe formation base film 6 is partially formed on the probe substrate 107 as shown in FIG. 4B.

  In the present embodiment, the probe forming base film 6 is partially surrounded by an insulating region 41 formed by exposing the insulating film 4 as shown in the perspective view of the probe substrate 107 in FIG. Removed. In the present embodiment, two long and narrow probe base film regions 61 formed by the probe forming base film 6 are formed on the probe substrate 107. Although not shown, when the contact probe 1 is fixed to the probe substrate 107, it is preferable to form the probe forming base film 6 so as to cover a plurality of electrodes formed on the probe substrate 107.

  Next, as shown in FIG. 4C, a first conductive film 51 is formed on the insulating film 4 and the probe forming base film 6 using copper. The first conductive film 51 is also preferably formed by vacuum deposition such as sputtering.

  Although not shown, a photoresist layer made of a photosensitive organic material is applied on the first conductive film 51 to form a resist layer. Thereafter, the resist layer is partially removed by selectively exposing the surface of the resist layer.

  The portion from which the resist layer has been removed is dry-etched with argon ions to remove the first conductive film 51 except the portion where the resist layer remains. Then, by removing the resist layer completely, the first conductive film 51 is formed on the probe substrate 107 as shown in the perspective views of the probe substrate 107 in FIG. A conductive region 51a, a probe base film region 61 composed of the probe forming base film 6, and an insulating region 41 composed of the exposed insulating film 4 are formed.

  In the present embodiment, as described above, in FIG. 4D, the long and thin first conductive region 51a is formed in the center portion of the probe substrate 107 with the insulating region 41 interposed therebetween, and this long and thin first conductive layer is formed. A long and thin rectangular probe forming base film 6 is formed outside the conductive region 51 a via the insulating region 41. The first conductive region 51a and the probe base film region 61 are insulated from each other by the insulating region 41. In addition, the 1st electroconductive area | region 51a formed of the 1st electroconductive film 51 is the elongate which extends in the direction orthogonal to this longitudinal direction at the longitudinal direction both ends of the elongate area | region of a center part, as shown in FIG. The region is also formed continuously.

  FIG. 4E shows a first resist formation step of forming the first resist layer 71 so as to have the first opening 71a exposing the insulating region 41 and the first conductive region 51a sandwiched between the insulating regions 41. Is shown. First, a photoresist made of a photosensitive organic material is applied to the entire surface of the probe substrate 107 to form a first resist layer 71. Thereafter, the first resist layer 71 is partially removed by selectively exposing the surface of the first resist layer 71. A first opening 71a is formed by partially removing the first resist layer 71. In the present embodiment, as shown in the perspective views of the probe substrate 107 in FIGS. 4E and 8, the area of the insulating region 41 exposed in the first opening 71a is equal to that of the first conductive region 51a. The first opening 71a is formed so as to be larger than the area.

  The remaining first resist layer 71 is in a state of covering all of the probe-forming base film 6 and a part of the first conductive film 51 as shown in FIGS. The first conductive film 51 and the insulating film 4 are exposed in the first opening 71a. As shown in FIG. 8, the boundary line between the first conductive region 51a and the insulating region 41 appears on a straight line in the first opening 71a.

  5A to 5E show a sacrificial layer forming process for forming the sacrificial layer 8 made of copper. During this step, the step shown in FIG. 5A is the first sacrificial layer forming step. By applying a voltage to the first conductive film 51 from the state of FIG. 4E, copper is electroplated on the upper surface of the first conductive film 51 as shown in FIG. 5A. At this time, copper is plated and deposited not only on the upper surface of the first conductive film 51 but also on the end surface which is the etching surface, and the copper plating overflows from the upper surface of the first conductive film 51, thereby In addition to covering the upper surface and the end surface of the film 51, the film 51 is also formed on a part of the insulating film 4.

  Thus, the 1st sacrificial layer 81 which has the base curved surface 81a as shown to Fig.5 (a) is formed by electroplating copper. The base curved surface 81a of the first sacrificial layer 81 rises from the insulating film 4 and bends toward the first conductive film 51 as shown in the partial perspective views of the probe substrate 107 in FIGS. Formed as follows. Specifically, the plating for forming the first sacrificial layer 81 extends from the end face of the first conductive film 51 onto the insulating film 4 in an eave shape. A base curved surface 81 a that rises in the insulating region 41 and bends toward the first conductive film 51 is formed at the peripheral portion of the portion extending in the eaves shape.

  When the first sacrificial layer 81 is formed, the first resist layer 71 is completely removed, and the second conductive film 52 is formed on the probe substrate 107 using copper as shown in FIG. 5B. . In the present embodiment, the process shown in FIGS. 5B and 5C is the second conductive film forming process. The second conductive film 52 is also preferably formed by vacuum deposition such as sputtering.

  Although not shown, a photoresist layer made of a photosensitive organic material is applied on the second conductive film 52 to form a resist layer. Thereafter, the resist layer is partially removed by selectively exposing the surface of the resist layer.

  The portion from which the resist layer has been removed is dry-etched with argon ions to remove the second conductive film 52 except for the portion where the resist layer remains. Then, by completely removing the resist layer, the second conductive film 52 is formed on the probe substrate 107 as shown in the perspective views of the probe substrate 107 in FIG. 5C and FIG. A conductive region 52 a, a probe base film region 61 composed of the probe forming base film 6, and an insulating region 41 composed of the exposed insulating film 4 are formed.

  In the present embodiment, as shown in FIG. 10, not only on the first sacrificial layer 81 and the insulating region 41 exposed adjacent to the first sacrificial layer 81, but also on the exposed first conductive film 51. Also, the second conductive film 52 is formed to form the second conductive region 52a. Of the second conductive region 52a, the second conductive film 52 formed on the first sacrificial layer 81 and the insulating region 41 has two locations in contact with the insulating film 4 as shown in FIG. A rib-shaped portion and a mountain-shaped portion that rises from the end of the rib-shaped portion along the upper surface of the first sacrificial layer 81 and has a flat central portion. The second conductive region 52a and the probe base film region 61 are in a state of being insulated by the insulating region 41, respectively.

  FIG. 5D shows a second resist formation step of forming the second resist layer 72 so as to have the second opening 72a exposing the insulating region 41 and the second conductive region 52a sandwiched between the insulating regions. Show. First, a photoresist made of a photosensitive organic material is applied to the entire surface of the probe substrate 107 to form a second resist layer 72. Thereafter, the surface of the second resist layer 72 is selectively exposed to partially remove the second resist layer 72. By partially removing the second resist layer 72, a second opening 72a is formed.

  The remaining second resist layer 72 is in a state of covering all of the probe forming base film 6 as shown in FIG. The second conductive film 52 and the insulating film 4 are exposed in the second opening 72a. Since the first sacrificial layer 81 is completely covered by the second conductive film 52, it is not exposed in the second opening 72a. A boundary line between the second conductive region 52a and the insulating region 41 appears on a straight line in the second opening 72a.

  FIGS. 5E to 6A show a second sacrificial layer forming step for forming the second sacrificial layer 82 made of copper. By applying a voltage to the first conductive film 51 from the state of FIG. 5D described above, as shown in FIG. 5E via the first conductive film 51 and the first sacrificial layer 81, Copper is electroplated on the upper surface of the second conductive film 52. At this time, copper is plated and deposited not only on the upper surface of the second conductive film 52 but also on the end surface which is an etching surface, and the copper plating overflows from the upper surface of the second conductive film 52, and the second conductive In addition to covering the upper surface and end surface of the film 52, the film 52 is also formed on a part of the insulating film 4. By electroplating copper in this manner, a stepped second sacrificial layer 82 having a first curved surface 82a and a second curved surface 82b as shown in FIG. 5E is formed.

  Then, when the second resist layer 72 is removed, a step having a first curved surface 82a and a second curved surface 82b on the probe substrate 107 as shown in the partial perspective views of the probe substrate 107 in FIG. 6A and FIG. A second sacrificial layer 82 is obtained. The first curved surface 82a is formed so as to rise in the insulating region 41 of the probe substrate 107 and bend toward the second conductive region 52a. Specifically, the plating for forming the second sacrificial layer 82 extends from the end face of the second conductive film 52 onto the insulating film 4 in an eaves shape. A first curved surface 82 a that rises in the insulating region 41 and bends toward the second conductive film 52 is formed at the peripheral portion of the portion extending in the eaves shape. The second curved surface 82b is formed above the base curved surface 81a of the first sacrificial layer 81 at a position above the first curved surface 82a. Specifically, the second curved surface 82b is formed to have an arc that is higher in the probe height direction than the first curved surface 82a and rises from the end side of the second conductive film 52 toward the center. .

  FIG. 6B shows a third resist forming step of forming a third resist layer 73 for forming a probe having a plurality of long and narrow third openings 73a. A third resist layer 73 is formed on the probe substrate 107 by applying a photoresist again, and the surface of the third resist layer 73 is selectively exposed, whereby a part of the third resist layer 73 is formed. Are removed, and a plurality of long and thin third openings 73 a are formed in accordance with the shape of the beam portion 3 of the contact probe 1. The third opening 73 a is formed so as to expose the second sacrificial layer 82 and the probe forming base film 6 with the insulating region 41 interposed therebetween.

  The remaining third resist layer 73 covers substantially the entire insulating film 4 as shown in the partial perspective views of the probe substrate 107 in FIGS. 6B and 13. The elongated third openings 73a are formed in two locations in the longitudinal direction, and a plurality of these two third openings 73a are formed with a predetermined pitch in the probe width direction. The third resist layer 73 between the two third openings 73a formed in the longitudinal direction is formed on the central portion of the mountain-shaped second sacrificial layer 82, and serves as a partition between the two third openings 73a. ing. That is, the partition portion of the third resist layer 73 formed on the center portion of the second sacrificial layer 82 becomes the end portion in the longitudinal direction of the third opening portion 73a, and the probe forming base film on the other longitudinal end portion side. Two third openings 73a are formed so that 6 is exposed.

  In the present embodiment, as shown in FIGS. 6B and 13, the second sacrificial layer 82 is exposed on one side in the longitudinal direction of each third opening 73a, and the probe-forming base film 6 is in the longitudinal direction. Exposed on the other side, the insulating film 4 is slightly exposed between the second sacrificial layer 82 and the base film 6 for probe formation. The third opening 73a is formed in the third opening 73a so that the first curved surface 82a of the second sacrificial layer 82 rises from the insulating film 4 and rises toward the center of the second sacrificial layer 82. .

  6C to 6E show a probe formation process for forming the contact probe 1. FIG. As shown in FIG. 6C, the contact probe 1 is formed on the second sacrificial layer 82. In the present embodiment, by applying a voltage to the second sacrificial layer 82 via the first conductive film 51, nickel cobalt alloy (Ni—Co) is converted into the second sacrificial layer 82 in each third opening 73a. Electroplate on top. By this electroplating, a nickel cobalt alloy grows on the second sacrificial layer 82 and the probe metal layer 91 is formed.

  When the probe metal layer 91 is grown until it contacts the probe formation base film 6, the probe metal layer 91 and the probe formation base film 6 are electrically connected, and the nickel cobalt is also formed on the probe formation base film 6. The alloy grows and the probe metal layer 91 is continuously formed from the second sacrificial layer 82 to the probe-forming base film 6. By forming the probe metal layer 91, the probe metal layer 91 corresponding to the substrate fixing portion 31 and the elastic deformation portion 32 of the beam portion 3 is formed.

  After the probe metal layer 91 is formed, the third resist layer 73 is removed, and a fourth resist layer 74 is formed by applying a photoresist again as shown in FIG. 6D. Then, by selectively exposing the surface of the fourth resist layer 74, a part of the fourth resist layer 74 is removed, and a fourth opening 74a is formed. The fourth opening 74 a is formed by removing the resist in a region corresponding to the contact portion 2.

  Next, as shown in FIG. 6D, the rhodium layer 92 is formed in the fourth opening 74a by electroplating rhodium (Rh). Since the upper surface of the rhodium layer 92 needs to be formed on a smooth surface and the height of the rhodium layer 92 laminated on each probe metal layer 91 must be uniform, the rhodium layer 92 is polished together with the fourth resist layer 74. Then, the upper surface of the rhodium layer 92 is flattened. This rhodium layer 92 constitutes the contact portion 2.

  Then, when the fourth resist layer 74 is removed, the plurality of contact probes 1 are fixed on the probe substrate 107 through the probe formation base film 6. Further, as shown in FIGS. 6E and 14, the second sacrificial layer 82, the second conductive film 52, the first sacrificial layer 81, and the first conductive film 51 are removed using a copper etchant. Then, the probe forming base film 6 exposed on the probe substrate 107 is removed by dry etching. The probe forming base film 6 is removed so that the probe forming base film 6 formed under the contact probe 1 is separated for each contact probe 1. Therefore, the probe forming base film 6 covered with the probe metal layer 91 is left. By separating the probe forming base film 6 in this manner, the contact probes 1 fixed on the probe substrate 107 are obtained so that the contact probes 1 do not conduct. This step is a sacrificial layer removal step.

  In the present embodiment, the first conductive film 51, the first sacrificial layer 81, the second conductive film 52, and the second sacrificial layer 82 are sequentially electroplated on the probe substrate 107 so that the area gradually increases. The sacrificial layer 8 having a step portion formed by a curved surface can be easily formed by laminating the layers. In addition, since the sacrificial layer 8 formed in this way can be formed entirely of a conductive material, the sacrificial layer will not be damaged even if the temperature rises during the manufacturing process. A contact probe 1 having a portion can be formed.

  Further, in the manufacturing method according to the present embodiment, the contact probe 1 is formed from the side fixed to the probe substrate 107 to the free end side. Therefore, the contact probe 1 is formed on the probe substrate 107 at the same time as the contact probe 1 is formed. Can be fixed. Therefore, the work of fixing the contact probes 1 to the probe substrate 107 one by one can be eliminated, and the manufacturing cost can be reduced.

  Furthermore, according to the contact probe manufacturing method of the present embodiment, a pair of the contact probes can be formed on the probe substrate 107 so that these free ends face each other. Therefore, in the contact probe manufacturing method of the present embodiment, two rows of contact probes 1 arranged at a predetermined pitch in the beam width direction are formed so that the free ends of the beam portions 3 face each other. Suitable for fixing to the probe substrate 107. That is, at the same time that each contact probe 1 is formed, each contact probe 1 can be fixed to the probe substrate 107 with the above arrangement.

  In addition, according to the contact probe manufacturing method of the present embodiment, the contact probe can be formed by reducing the distance between the free ends of the pair of contact probes. It can be efficiently formed on the probe substrate 107.

  As described above, according to the contact probe manufacturing method of the present embodiment, even when the contact probe 1 having a cantilever structure is laminated by electroplating in a direction perpendicular to the probe substrate 107, it is easy. In this way, the contact probe 1 having a plurality of curved portions having a desired shape and size can be formed. Even if the contact probe 1 is brought into contact with the inspection object 102 and elastically deformed, it is possible to eliminate stress concentration on a part of the contact probe 1 by forming the curved portion. Can extend the lifetime of Furthermore, since the contact probe 1 has a plurality of curved portions formed in a step shape, the contact probe 1 can be prevented from coming into contact with the inspection object even with a large overdrive amount.

  In the above-described embodiment, the sacrificial layer 8 having a step portion formed by a curved surface is formed in a mountain shape, and a pair of contact probes 1 are placed on the mountain-shaped sacrificial layer 8 so that the free ends thereof face each other. The manufacturing method for forming the contact probe 1 has been described. In the manufacturing method of the present invention, the sacrificial layer 8 is formed so that the side surface opposite to the first curved surface 81 is a surface that rises perpendicular to the probe substrate 107. You can also.

  In that case, the first resist layer is formed such that the wall surface of the opening of the first resist layer is positioned on the first conductive film 51 formed on the probe substrate 107. By forming the first resist layer in this way, a base curved surface is formed only in a portion adjacent to the insulating region in the first conductive film 51 in the opening, and other parts including the opposite side of the base curved surface are formed. The portion is formed with a first sacrificial layer in which a side surface rising vertically from the probe substrate 107 is formed by the wall surface of the opening. When the second conductive film and the second sacrificial layer are formed, the wall surfaces of the openings of the resist layers are formed on the first sacrificial layer and the second conductive film so that the base curved surface is located in the opening. The second conductive film and the second sacrificial layer are formed in a state of being positioned at the position. Thus, by sacrificing the sacrificial layers, a sacrificial layer having one each of the first curved surface and the second curved surface can be formed.

  Furthermore, in each of the above embodiments, the manufacturing method of the two-stage contact probe has been described. However, according to the manufacturing method of the present invention, a contact probe having three or more curved portions can also be formed. For example, in the case of forming a three-stage contact probe, after the second sacrificial layer is formed, the insulating film in the insulating region adjacent to the second sacrificial layer is further formed on the second sacrificial layer. A sacrificial layer having three curved steps can be formed by forming a third conductive film thereon and forming a third sacrificial layer on the third conductive film. Then, by forming the contact probe on the three-stage sacrificial layer, it is possible to form a contact probe having three curved portions in a staircase pattern.

  In each of the above-described embodiments, the example in which the contact probe 1 is directly fixed on the probe substrate 107 while the contact probe 1 is formed has been described. However, the method for manufacturing a contact probe having a curved portion according to the present invention is described. The present invention is not limited to these embodiments, and can also be applied to the case where the contact probe 1 is formed on a separately prepared insulating substrate and the contact probe is finally peeled off from the insulating substrate. When the contact probe is finally peeled from the insulating substrate, for example, a plurality of contact probes may be formed on one sacrificial layer. In this case, the plurality of contact probes together with the sacrificial layer are peeled from the insulating substrate, and the contact probes are arranged on the probe substrate together with the sacrificial layer. And after fixing a contact probe to a probe board | substrate, a contact probe can be easily fixed to a probe board | substrate by removing a sacrifice layer.

It is the figure which showed an example of schematic structure of the probe apparatus 100 containing the probe card 110 by embodiment of this invention, and the mode inside the probe apparatus 100 is shown. It is the figure which showed the structural example of the probe card 110 in the probe apparatus 100 of FIG. It is the side view which showed an example of the contact probe by Embodiment 1 of this invention. 6 is a diagram showing an example of a process for forming a contact probe according to Embodiment 1. FIG. FIG. 8 is a diagram illustrating an example of a process for forming a contact probe according to the first embodiment, and illustrates a continuation of FIG. FIG. 6 is a diagram showing an example of a process for forming a contact probe according to the first embodiment, and shows a continuation of FIG. 4D is a partial perspective view of the probe substrate 107 corresponding to FIG. 4D, showing a state in which the first conductive region 51 a, the probe base film region 61, and the insulating region 41 are formed on the probe substrate 107. Yes. FIG. 9 is a partial perspective view of the probe substrate 107 corresponding to FIG. 4E, showing a state where a first resist layer 71 having a first opening 71 a is formed on the probe substrate 107. FIG. 6 is a partial perspective view of the probe substrate 107 corresponding to FIG. 5A, showing a state in which a first sacrificial layer 81 is formed on the first conductive film 51 of the probe substrate 107. FIG. 6C is a partial perspective view of the probe substrate 107 corresponding to FIG. 5C, showing a state in which the second conductive film 52 is formed on the first sacrificial layer 81 and the insulating film 4 of the probe substrate 107. ing. FIG. 6E is a partial perspective view of the probe substrate 107 corresponding to FIG. 5E, in which a second sacrificial layer 82 is formed on the second conductive film 52 exposed in the second opening 72 a of the second resist layer 72. Shows the state. FIG. 7 is a partial perspective view of the probe substrate 107 corresponding to FIG. 6A, showing a state where the second resist layer 72 is removed and a second sacrificial layer 82 is formed on the probe substrate 107. FIG. 7C is a partial perspective view of the probe substrate 107 corresponding to FIG. 6C, on which the third resist layer 73 having the third opening 73 a is formed and on the second sacrificial layer 82 exposed in the third opening 73 a. The figure shows a state in which the probe metal layer 91 is formed. FIG. 7 is a partial perspective view of the probe substrate 107 corresponding to FIG. 6E, showing a state where the contact probe 1 is fixed on the probe substrate 107.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact probe 2 Contact part 3 Beam part 31 Substrate fixing | fixed part 32 Elastic deformation part 4 Insulating film 41 Insulating area | region 51 1st electroconductive film 51a 1st electroconductive area | region 52 2nd electroconductive film 52a 2nd electroconductive area | region 6 Probe Formation base film 61 Probe base film region 71 First resist layer 71a First opening 72 Second resist layer 72a Second opening 73 Third resist layer 73a Third opening 74 Fourth resist layer 74a Fourth opening 8 Sacrificial layer 81 First sacrificial layer 81a Base curved surface 82 Second sacrificial layer 82a First curved surface 82b Second curved surface 91 Probe metal layer 92 Rhodium layer 100 Probe device 102 Inspection object 121 Electrode pad 103 Movable stage 104 Drive device 105 Housing 106 Main board 161 External terminal 162 Connector 107 Probe board 108 Connecting member 110 Plow Card

Claims (3)

A first conductive film made of a conductive material is formed on an insulating substrate, a first conductive region made of the first conductive film on the main surface of the insulating substrate, and an insulation adjacent to the first conductive region. A first conductive film forming step for forming a conductive region;
By electroplating a conductive material on the first conductive film, a first sacrificial layer having a base curved surface that rises at the peripheral edge extending to the outside of the first conductive region and curves toward the first conductive region is formed. A first sacrificial layer forming step to be formed;
A second conductive film made of a conductive material is formed on the first sacrificial layer and the insulating region exposed adjacent to the first sacrificial layer, and the second conductive film is formed on the main surface of the insulating substrate. A second conductive film forming step of forming a second conductive region and an insulating region adjacent to the second conductive region,
By electroplating a conductive material on the second conductive film, the first curved surface rising at the peripheral edge extending to the outside of the second conductive region and bending toward the second conductive region, and the base curved surface A second sacrificial layer forming step of forming a second sacrificial layer formed above and having a second curved surface rising toward the center from the end side of the second conductive film;
A probe forming step of forming a contact probe on the second sacrificial layer;
A contact probe comprising: a sacrificial layer removing step of removing the first conductive film, the first sacrificial layer, the second conductive film, and the second sacrificial layer by etching the conductive material. Production method. In the first conductive film forming step, a first conductive film is formed so as to form a first conductive region sandwiched between the insulating regions,
2. The method of manufacturing a contact probe according to claim 1, wherein in the first sacrificial layer forming step, the first sacrificial layer is formed so as to have two opposing base curved surfaces. In the second conductive film forming step, a second conductive film is formed so as to form a second conductive region sandwiched between the insulating regions,
3. The method of manufacturing a contact probe according to claim 2, wherein in the second sacrificial layer forming step, the second sacrificial layer is formed so as to have two first curved surfaces and two second curved surfaces facing each other.

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