JP6529599B2 - Electrical contacts - Google Patents

Description

  The present invention relates to a method of manufacturing a three-dimensional structure, a mold used for the manufacture, and an electrical contact as the three-dimensional structure to be manufactured, and in particular, a fine metal having a depression formed by an inclined surface on the surface. The present invention relates to a method of manufacturing a three-dimensional structure, a mold having an inclined surface for forming the shape of a depression on the surface of the three-dimensional structure, and an electrical contact manufactured by this manufacturing method.

As a method of producing a three-dimensional structure from metal, it is common to pour molten metal into a plurality of combined molds, and after cooling, remove the mold to produce a desired three-dimensional structure. However, in the case where the structure is a fine three-dimensional structure having a diameter of about 10 microns to several tens of microns and a length of about 100 microns, different techniques are performed. For example, in the case of producing an electrical contact (probe) used for electrical inspection of a semiconductor device, the three-dimensional structure to be produced may be an upper (tip), a middle (body), a lower (base), etc. There is a method of dividing into a plurality of parts, and sequentially stacking and creating the body and base from the tip end.

  If this fine three-dimensional structure is required to have a unique shape like a probe, that is, in the probe, the tip is pointed like a pyramid or inclined obliquely in order to contact the electrode of the semiconductor device And various shapes are required. When forming an inclined surface at the tip, form a recess with an inclined surface in the substrate, form a metal thin film on the inner wall surface of the recess, and electroplate using this metal thin film as an electrode to form a metal of the upper shape Forming a layer is performed.

  Then, after forming the metal layer at the tip, in order to form the metal layer of the trunk, a resist is applied, this is exposed with a predetermined pattern, and developed to form an exposed surface according to the pattern, Patent Document 1 proposes that metal layers are stacked on an exposed surface by electroforming to form a metal three-dimensional structure of a predetermined pattern, and similarly to sequentially form a metal layer of the base. Thus, after forming the metal layer of the tip portion, the body portion and the base portion, the substrate, the metal thin film and the resist are removed to form a three-dimensional structure of the metal layer. However, in the three-dimensional structure disclosed in Patent Document 1, as a means for forming the shape of the protrusion on the upper side, pressing a hard tool such as a diamond indenter has been described, but a specific description is given. Rather, photolithography has become mainstream and stuck because the means of realization has not been shown at all.

Unexamined-Japanese-Patent No. 2003-121469

  This method of producing a three-dimensional structure by electroforming has no particular problem when producing one structure, but particularly when producing many three-dimensional structures at the same time, the sloped surface of the tip portion is There was a problem in production.

  Conventionally, in order to form a recess with an inclined surface in a substrate, it is common to expose a portion forming the recess and press a hard tool such as a diamond indenter with a sharpened tip or perform etching. However, if the tip has a pointed shape, the die of the desired shape can be obtained by pressing and molding a pointed mold, but a depression is formed on the surface of the tip. In this case, there is a problem that there is no mold having an appropriate shape. In addition, although it is conceivable to form the sloped surface in a step-like manner by laminating multiple layers, a large number of layers are required to form a smooth surface as much as possible, resulting in a problem that it takes a lot of process time. Furthermore, it was unexpected to produce a three-dimensional structure having a recess with an inclined surface at the tip.

An object of the present invention is to provide an electrical contact configured to guide an electrode to a central portion of tip positions of a plurality of fingers .

  The electric contact according to the present invention comprises a pedestal and a plurality of fingers extending perpendicularly from the pedestal, and an inclination is made toward the central portion of the plurality of fingers of the pedestal at the tips of the plurality of fingers. It has a surface, and the elastic force of the plurality of fingers is different.

The electrode can be guided to the center of the tip positions of the plurality of fingers by having an inclined surface which is inclined toward the center of the plurality of fingers at the tips of the plurality of fingers, and the elastic force of the plurality of fingers Can be obtained, the effect that the movement direction can be determined can be obtained.

It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is explanatory drawing which shows the comparative example of a metal mold | die. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is the schematic which shows the state of the electroplating of this invention. It is the schematic which shows the state of the electroplating of this invention. It is the schematic which shows the state of the electroplating of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. It is the schematic which shows the state which forms a through-hole in the flat plate of this invention. It is the schematic which shows the state which forms a through-hole in the flat plate of this invention. It is process drawing which shows the manufacturing process of the three-dimensional structure of this invention. FIG. 1 is a schematic view showing an example of a probe of the present invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is explanatory drawing of the metal mold | die used for the manufacturing process of this invention. It is the schematic which shows the state of shaping | molding by the metal mold | die of this invention.

Embodiment 1
FIG. 1 is a process diagram showing molding by a die in the process of the first embodiment of the present invention. As shown in the figure, in the process of FIG. 1, a mold 1 is used to apply pressure to a first acrylic plate 2 as a resin plate to perform molding. At the time of this molding, the first acrylic plate 2 is heated so as to be easily deformed. Further, the first acrylic plate 2 is easily deformed by heating the mold 1 as well. The cross-sectional shape of the mold 1 used here is shown in FIG. 1, but the production of the mold 1 is performed as shown in FIGS. First, as shown in FIG. 2, the through hole 12 is provided on the central axis of the cylindrical main body 11, and etching is performed to form the inclined surface 13 at the opening of the through hole 12 as shown in FIG. . The mold 1 can be made of a material containing nickel as a main component.

  As shown in FIG. 2, the mold 1 has a through hole 12 in the center axis, and then, as shown in FIG. 3, a desired inclined surface 13 is formed by etching. As shown in FIG. 3, providing the through hole 12 at the central axis of the cylindrical main body 11 has a unique effect.

The mold 1 of the comparative example with respect to the mold 1 of the present invention has a shape without the through hole 12 as shown in FIG. When this mold 1 is pressed against the first acrylic plate 2 and the first acrylic plate 2 starts to be molded, an air reservoir is formed between the depression of the central portion of the mold 1 and the surface of the first acrylic plate 2. As a result, the pressing force of the mold 1 becomes difficult to be transmitted to the first acrylic plate 2, and the molding is not as expected. In order to prevent this air accumulation, the mold 1 needs a through hole 12 for removing air.
In addition, although the metal mold | die shown in FIG. 2 and FIG. 3 has shown the thing from which the outer side is cylindrical shape, the outer shape is not restricted to it and the metal in the case of producing several structures simultaneously As the mold 1, as shown in FIG. 5, a plurality of regions are set on the surface of a flat plate-shaped main body 11, a through hole 12 is provided in the central part of each region, and etching is performed centering on the through hole 12. The inclined surface 13 can also be provided. FIG. 5 illustrates the case where the mold 1 is in the shape of a flat plate, and a part of the mold 1 is broken for convenience of illustration.

  When pressure is applied to the first acrylic plate 2 using the mold 1 shown in FIG. 3 and then the mold 1 is removed, the first acrylic plate 2 is molded as shown in FIG. The same inclined surface 21 as the shape of the inclined surface 13 remains, and the portion of the through hole 12 of the mold 1 allows the first acrylic plate 2 to be released at the time of molding, so a slight protrusion 22 is made. Since the drawing shown in FIG. 6 is a cross-sectional view, the actual shape is difficult to understand, so the shape of the first acrylic plate 2 after molding is shown in FIG. 7 in a perspective view. As shown in FIG. 7, the first acrylic plate 2 has an inclined surface 21 and a protrusion 22.

  Note that although only one molding portion is shown in the molding process of FIG. 7, at the time of actual processing, as shown in FIG. 8, efficiency can be improved by simultaneously performing a plurality of portions.

  After the molding step of FIG. 6, as shown in FIG. 9, a sacrificial metal layer 3 is formed on the surface of the first acrylic plate 2 after molding. The sacrificial metal layer 3 serves as an electrode when manufacturing the three-dimensional structure 100 by electroplating. Next, as shown in FIG. 10, the whole is covered with a resist layer 4, and as shown in FIG. 11, the resist layer 4 is masked to expose the sacrificial metal layer 3 of the inclined surface 21. The surrounding resist layer 41 is left.

  Further, as shown in FIG. 12, the main metal layer 5 is formed on the surface of the sacrificial metal layer 3 surrounded by the inner wall surface of the resist layer 41 by electroplating.

  Here, a state in which electroplating is performed using the exposed sacrificial metal layer 3 will be described using FIG. The state of electroplating shown in FIG. 13 shows the case where there is a sacrificial metal layer on the bottom and the protruding part of the central part. In this case, the plating layer is formed along the sacrificial layer, and the plating layer is formed from the bottom and the wall of the uneven portion. The state of electroplating shown in FIG. 14 shows the case where the sacrificial layer is exposed only on the bottom surface. In this case, a plating layer parallel to the inclination of the bottom surface is formed.

  The state of electroplating shown in FIG. 15 shows a comparative example in the case where the sacrificial metal layer is spread on the inner wall surface of the recess. In this case, since the plating layer is formed from the bottom and the side, in some cases, the plating solution is trapped in the plating layer.

  After the main body metal layer 5 is formed, the first acrylic plate 2, the resist layer 4 and the main body metal layer 5 are integrally formed and polished as shown in FIG. This reference board 20 is a structure in which the structure of the upper part (tip part) of the three-dimensional structure 100 to be created is embedded, and based on this part, the middle part (leg part) and the lower part (base part) ) Is formed by electroplating.

  The reference board 20 is constituted by the first acrylic plate 2, the sacrificial metal layer 3, the resist layer 4 and the main body metal layer 5. Here, although the first acrylic plate 2 is pressurized at the time of molding, while the back surface of the first acrylic plate 2 is maintained flat, the mold 1 has a predetermined depth of the first acrylic plate 2. You will get into it. Therefore, the main metal layer 5 is adjusted to the reference height by polishing the resist layer 4 and the main metal layer 5 with reference to the back surface of the first acrylic plate 2.

  When the reference board 20 is completed, as shown in FIG. 17, in order to form the middle part (legs) of the three-dimensional structure 100 on the reference board 20, the masking layer 6 is formed, and the middle part Form the legs). In the first embodiment, a special shape is shown because a probe is illustrated, but even if it is another structure, various shapes can be realized if the reference board 20 is completed. Become.

  As the masking layer 6, usually, a resist layer is overlaid on the reference board 20, and the resist layer is used after removing a predetermined pattern. The middle portion (leg portion) of the three-dimensional structure 100 is formed by laminating a metal layer by electroplating on the portion of the removed pattern of the resist layer.

However, when a resist layer is used as the masking layer 6, a thick layer can not be formed at once. Therefore, since the resist layer formation, the metal layer formation, and the polishing are repeatedly performed, time for processing There is a problem that it hangs.
This problem can be overcome by using a second acrylic plate 7 of a predetermined thickness.

  The second acrylic plate 7 has a thickness of the dimension of the middle portion (leg portion) of the three-dimensional structure 100 and is provided with the through hole 71 at a position corresponding to the leg portion. The second acrylic plate 7 can be overlaid on the reference board 20, and the leg metal layer can be formed by electroplating using the body metal layer 5 exposed in the through hole 71 as an electrode.

In the second acrylic plate 7 used here, since the through holes 71 are extremely minute, a special method is required to provide the through holes 71.
A method of providing the through holes 71 in the second acrylic plate 7 will be described. As shown in FIG. 18, a plate 70 thicker than the acrylic plate 7 to be used is prepared, and a hole 73 is formed from the surface side of the thick plate 70 by the through hole mold 72. After the holes 73 are formed, as shown in FIG. 19, the back side of the thick plate is polished to a predetermined thickness. Then, the polishing is repeated until the holes 73 become the through holes 71. The position of the second acrylic plate 7 thus prepared is adjusted on the reference board 20 by an alignment mark or the like, and then superimposed on a predetermined place.

The preparation of the second acrylic plate 7 is carried out in parallel with the manufacture of the reference plate 20, and the process can be shortened by combining the two structures at the ready stage.
Similarly to the formation of the middle part (leg part) of the three-dimensional structure 100, the third acrylic plate 8 in which the through holes 81 of a predetermined pattern are formed is also superimposed on the lower part (base part), and electroplating is performed. The lower part (base part) of the three-dimensional structure 100 can be created.

  When the lower portion (base portion) of the three-dimensional structure 100 is manufactured, the first acrylic plate 2, the sacrificial metal layer 3, the resist layer 41, the second acrylic plate 7 and the third acrylic plate 8 are removed as shown in FIG. As shown in the above, it is possible to obtain a three-dimensional structure 100 having a predetermined shape in which the structure of the upper portion (tip portion), the structure of the middle portion (leg portion) and the structure of the lower portion (base portion) are integrated.

The method of manufacturing the three-dimensional structure 100 makes it possible to create a three-dimensional structure having a special shape at the tip.
Next, as an example of a three-dimensional structure, a probe 101 having a special shape at the tip will be described.
The probe 101 is in contact with the electrode of the semiconductor device to detect an electrical signal associated with the operation of the semiconductor device, and needs to be in contact with the electrode of the semiconductor device. For this reason, although various probe shapes have been considered, when the electrode of the semiconductor device has a ball shape, there is no one configured to wrap the electrode.

  That is, as shown in FIG. 21, this special shaped probe 101 is configured such that a plurality of vertically extending fingers 1011 are in contact with one electrode. In addition, the tip of the finger has an inclined surface 1012 so as to guide the ball-like electrode to the center of the tip position of the plurality of fingers. That is, the inclined surface 1012 is provided so as to be directed to the centers of the tips of the plurality of fingers 1011 with three or more fingers 1011. In addition, each finger 1011 is flexible and configured to flexibly contact the electrode of the semiconductor device.

  To change the expression, the overall shape of the probe 101 is similar to the shape of the wrist. The pedestal portion 1013 is connected like a palm, and has a shape in which the finger 1011 extends toward the contact object, and the tip of the finger 1011 contacts the electrode of the semiconductor device.

  Such a configuration allows the shape of the probe 101 to be in contact so as to wrap the electrode of the semiconductor device.

  Also, this special shape can be used for structures other than probes. For example, it can also be used as an electrical contact, as a structure for making an electrical connection. That is, when the electrode of the semiconductor device is ball-shaped, the structure is effective as an electrical connection with a plurality of fingers as a connection means in place of the lead frame.

  In addition, although the structure which contacts with four fingers 1011 is shown in FIG. 21 as a three-dimensional structure which aims at an electrical connection, when an electrical connection is assumed, when it is set as three fingers, a contact is stable. Have the effect of That is, in the case of four fingers, it is necessary for all the fingers to flex in order to contact all the fingers equally, and in the case where one finger does not contact if it is not flexed. There is. If the contact becomes unstable, it becomes an electronically minute discharge phenomenon, which causes disturbance in the electric signal to be handled. For this reason, it makes sense to use three fingers for stable contact.

  Also, since the three fingers are formed by electroplating here, the material is the same. Here, the flexibility or elastic force can be changed by changing the cross-sectional area of one or two of the three. By changing the elastic force to make the finger easy to be deformed, it is possible to determine the direction in which the electrode is moved when an external force is applied by the electrode of the semiconductor device or the like.

Embodiment 2
The shape of the mold according to the first embodiment is a shape in which a recess is provided at the central portion of a predetermined region, and is a shape obtained by cutting a conical shape from a cylindrical shape. On the other hand, in the second embodiment, in order to shorten the process after the molding of the resin plate by the mold, further investigation is advanced, and the shape of the mold based on the shape of the intended three-dimensional structure. Are defined.
That is, as shown in FIG. 21, the target three-dimensional structure is an electrical contact, and the pedestal portion 1013 is connected like a palm, and the finger 1011 is extended toward the contact object, The tip of the finger 1011 has a special shape in which an inclined surface 1012 is provided.

This specially shaped three-dimensional structure, especially the shape of the tip portion, is molded into a resin flat plate with a mold, and instead of the conical surface of the first embodiment, the tip portion of the finger requiring a slope It is a mold with a shape that protrudes only in a limited manner.
Specifically, as shown in FIG. 22, the mold 1 has a shape in which a protrusion 14 having an inclined surface 13 at its tip portion is provided to the main body 11. The point common to the first embodiment is that the central portion of the predetermined area is recessed. In the second embodiment, although the structure in which the projections 14 are arranged at four places is shown, the number can be further increased or decreased.

As shown in FIG. 23 as a perspective view in which a part of the mold 1 is cut away, the through hole 12 is provided in the main body 11 to provide a relief passage of resin in molding the resin plate. Further, as shown in FIG. 24, a plurality of grooves 15 are provided on the side surface of the projection 14 of the mold 1 along the direction in which the resin is pushed by the projection 14 (the direction of the arrow in the drawing). When the resin is molded using the mold 1, the resin is vibrated by the pressure of the mold 1 and is a groove 15 for preventing a large number of pulsations from remaining in the resin.
Also in the second embodiment, as in the first embodiment, the mold 1 can be disposed on a plurality of planes so as to simultaneously mold a plurality of portions. This state is as shown in FIG.

In addition, as shown to a figure, the front-end | tip part of protrusion 14 part of the metal mold | die 1 shown in FIG. 22 has not only the inclined surface 13, but a plane part. Even if this plane portion is not required as the shape of the target three-dimensional structure, it is a shape necessary for the mold. That is, in order to have the necessary mechanical strength as a mold, the structure of the block is required as much as possible, and in this mold, if this portion is made only to the inclined surface, it leads to breakage of the projection.
When a flat plate of resin is molded using the mold of the second embodiment, as shown in FIG. 26, the shape of the inclined surface of the tip portion of the three-dimensional structure as if the three-dimensional object is removed. You can get it.

  In the first and second embodiments, the shape of the tip portion of the three-dimensional structure is formed by molding a flat plate of resin by a mold, but in order to form a flat plate of resin by using a mold, a resin plate As the weight average molecular weight is preferably 1000 to 100000, and particularly an acrylic plate having a weight average molecular weight of 30000 or less is suitable. This is because when the resin is molded using a mold, it is considered that the memory of deformation at the time of molding tends to remain if the molecular weight is small.

In the embodiment of the present invention, although the case of using an acrylic plate as a flat plate has been described, it is of course possible to use a flat plate of other resin.
In the present invention, within the scope of the invention, the embodiments can be freely combined, or the embodiments can be appropriately modified or omitted.

Claims (1)

A pedestal, and a plurality of fingers vertically extending from the pedestal, the tip of the plurality of fingers having an inclined surface inclined toward a central portion of the plurality of fingers of the pedestal; An electrical contact characterized in that the elasticity of the finger is different .

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