socket

Abstract

To provide a socket which can be mounted on a surface and is equipped with a wiping function while being suitable for a narrow pitch.SOLUTION: A socket 100 of the present invention can be mounted on a surface of a circuit board 210. The socket 100 includes a plurality of contacts 110, and each contact 110 includes a contact portion 112 capable of coming into contact with a terminal of a semiconductor device, a locking portion 116 connected to the contact portion 112, and a substrate side contact portion 118 extended from the locking portion 116 and capable of coming into contact with a conductive area formed on a substrate surface. The socket 100 further includes a stopper member 120 holding the locking portions 116 of the plurality of contacts 110, and a guide member 180 disposed oppositely to the stopper member 120. The guide member 180 is provided with a plurality of through-holes 186 storing the respective substrate side contacts 118 projecting out from the stopper member 120.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a socket for mounting a semiconductor device such as a BGA (Ball Grid Array), a CSP (Chip Sized Package), or an LGA (Land Grid Array), and more particularly to a structure for surface mounting a socket on a circuit board. [Background technology]

[0002] Sockets are widely used as interfaces for electrically connecting semiconductor devices to circuit boards and the like. FIG. 1A illustrates a through-hole type socket 10. As shown in the figure, the socket 10 includes a base member 20, a cover member 30 that can reciprocate toward and away from the base member 20, a plurality of contacts 40 embedded in the base member 20, a contact restricting member 50 that restricts the positions of board-side contacts 42 of the contacts 40, an adapter 60 that can reciprocate relative to the contact restricting member 50, and a latch member 70 that presses against the surface of a semiconductor device such as a BGA. The upwardly extending contact portions of the contacts 40 are connected to terminals on the bottom surface of the semiconductor device, and the board-side contact portions 42 protrude from the bottom of the socket 10 through through holes in the contact restricting member 50. Post members 22 are provided at each corner of the base member 20, and the post members 22 are inserted into positioning holes in the circuit board to position them (see, for example, Patent Document 1). As shown in FIG. 1(B), the board-side contact portion 42 of the contact 40 is inserted into a through-hole 92 of the circuit board 90, and the board-side contact portion 42 is electrically connected to a conductive land or wiring pattern of the circuit board 90 by solder 94.

[0003] In a through-hole type socket 10, the board-side contact portions 42 of the contacts 40 are soldered to the through-holes 92 of the circuit board 90, which means that if the socket 10 breaks down, it takes time and effort to replace it. As a solution to this problem, Patent Document 2 discloses a surface-mount type socket in which the board-side contact portions of the contacts are not soldered into the through-holes of the circuit board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3566691 [Patent Document 2] Patent No. 6991782 Summary of the Invention [Problem to be solved by the invention]

[0005] Fig. 2 is a cross-sectional view of the socket of Patent Document 2, and Fig. 3 is a diagram showing the structure of the board-side contact portion of the contact. Surface-mount type socket 10A has a configuration generally similar to that of through-hole type socket 10, but a guide member 50A is provided below contact restricting member 50 so as to be movable in the vertical direction, and when guide member 50A moves upward, board-side contact portion 42A of contact 40A protrudes from through-hole 52 of guide member 50A. Board-side contact portion 42A is curved, for example, into a U-shape.

[0006] During the process of pressing the socket 10A against the circuit board 90, the board-side contact portion 42A comes into contact with the edge portion of the through-hole 90 (the inside of the through-hole is plated with Ag or Au) at a position offset from the through-hole 90, as shown in FIG. 3(A), and then, as shown in FIG. 3(B), the board-side contact portion 42A performs a wiping action with the edge portion WP, and finally the board-side contact portion 42A makes electrical contact with the edge portion of the through-hole 90 at multiple points.

[0007] However, since this socket 10A has a curved shape for the board-side contact portion 42A, it is necessary to provide a margin of space to prevent contact with adjacent contact portions, which creates the problem of making it difficult to achieve a narrow contact pitch.

[0008] SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a surface-mount type socket that is compatible with narrow pitches and has a wiping function. [Means for solving the problem]

[0009] The socket of the present invention is capable of being surface-mounted on a substrate and comprises a plurality of contacts made of a plate-shaped conductive material, each contact including a contact portion capable of contacting a terminal of a semiconductor device, a locking portion connected to the contact portion, and a substrate-side contact portion extending from the locking portion and capable of contacting a conductive area including an opening formed on the substrate, the substrate-side contact portion including an elastic deformation portion connected to the locking portion and a tip portion connected to the elastic deformation portion and having a narrow portion and a wide portion in the axial direction, the socket comprises a plurality of contacts, a holding member that holds the locking portions of the plurality of contacts, and a guide member that is movable in a direction toward or away from the holding member and has a plurality of through holes formed therein for inserting the board-side contact portions protruding from the holding member, and when the guide member is moved in a direction toward the holding member, the tip portion is allowed to enter the axial direction into the opening.

[0010] In one embodiment, the wide portion is larger than the diameter of the opening and the narrow portion is smaller than the diameter of the opening, and when the guide member moves toward the holding member, the narrow portion enters the opening and wipes the edge of the opening at a connection region between the wide portion and the narrow portion. In one embodiment, the contact has a generally constant thickness in a first direction, the elastic deformation portion protrudes in the first direction from the axial direction, and the tip portion has the narrow portion and the wide portion in a second direction perpendicular to the first direction. In one embodiment, the connection region slopes linearly or curvedly. In one embodiment, the tip portion has a wedge or inverted triangle shape. In one embodiment, when the guide member is located away from the holding member, a portion of the tip portion is located facing the opening in the board. In one embodiment, when the guide member moves in a direction approaching the holding member, the tip portion contacts the opening, and the tip portion, receiving an axial force, tilts in a certain direction due to the elastic deformation portion. In one embodiment, the through hole of the guide member is formed with an inclined surface to allow the tip portion to tilt. In one embodiment, the tip portion further includes an extension portion 118 extending axially from the narrow portion, and when the guide member is in a position away from the holding member, the extension portion enters the opening. In one embodiment, when the guide member moves in a direction approaching the holding member, the tip portion wipes the edge portion of the opening, and the extension portion wipes the inner wall portion of the through hole. In one embodiment, the opening is a through hole. In one embodiment, the socket further includes spring means for biasing the guide member in a direction away from the holding member. [Effects of the Invention]

[0011] According to the present invention, when the guide member is moved toward the holding member, the tip portion, which has a narrow portion and a wide portion in the axial direction, enters the opening in the circuit board in the axial direction, so that the tip portion can wipe the edge of the opening and obtain a good electrical connection between the socket and the circuit board. Furthermore, because the tip portion enters the opening in the axial direction, the contacts can be arranged at a narrower pitch than in conventional sockets. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1(A) is a cross-sectional view of a conventional through-hole type socket, and FIG. 1(B) is a cross-sectional view showing the connection between the contact and the through-hole. [Figure 2] FIG. 2 is a cross-sectional view of a conventional surface mount socket. [Figure 3] 10A and 10B are diagrams showing connections between board-side contact portions of contacts in a conventional surface mount socket and through holes. [Figure 4] 1 is a perspective view of a surface-mount type socket according to an embodiment of the present invention, as viewed from above; [Figure 5] 1 is an exploded perspective view of a surface-mount type socket according to an embodiment of the present invention; [Figure 6] 1 is a perspective view of a surface-mount type socket according to an embodiment of the present invention, viewed from below. [Figure 7] 1 is an exploded perspective view of a surface-mount type socket according to an embodiment of the present invention; [Figure 8] 1A and 1B are diagrams illustrating a connection between a surface mount type socket and a circuit board according to an embodiment of the present invention. [Figure 9] FIG. 9(A) is a cross-sectional view showing the schematic configuration of a surface mount type socket according to an embodiment of the present invention, FIG. 9(B) is an enlarged cross-sectional view of the guide member in the X direction, and FIG. 9(C) is an enlarged cross-sectional view of the guide member in the Y direction. [Figure 10] FIG. 10(A) is a plan view of the base member, and FIG. 10(B) is a side view including a partial cross section of the base member. [Figure 11]11A and 11B are diagrams illustrating a contact according to an embodiment of the present invention, in which FIG. 11A is a front view of the contact, FIG. 11B is a side view of the contact, and FIG. 11C is an enlarged view of a board-side contact portion. [Figure 12] 10A and 10B are diagrams illustrating the relationship between the board-side contact portion and the through-hole of the circuit board. [Figure 13A] FIG. 2 is a plan view of a holder according to an embodiment of the present invention. [Figure 13B] FIG. 2 is a plan view of a stopper member according to an embodiment of the present invention. [Figure 14] 14(A) is a plan view of a guide member according to an embodiment of the present invention, FIG. 14(B) is a cross-sectional view of the through-hole taken along line XX, and FIG. 14(C) is a cross-sectional view of the through-hole taken along line YY. [Figure 15] 1 is a schematic cross-sectional view showing a state in which the socket of the present embodiment is mounted on a circuit board. [Figure 16] 1 is a schematic cross-sectional view showing a state in which the socket of the present embodiment is pressed against a circuit board. [Figure 17] 17(A1) and (A2) are diagrams showing the relationship between the board-side contact portion and the through-hole of the circuit board in the state shown in FIG. 15, and FIGS. 17(B1) and (B2) are diagrams showing the relationship between the board-side contact portion and the through-hole of the circuit board in the state shown in FIG. 16. [Figure 18] 10A and 10B are diagrams showing the configuration of contacts of a socket according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] The best mode for carrying out the present invention will be described in detail below with reference to the drawings. Figures 4 to 8 are perspective views showing the schematic configuration of a surface-mountable socket according to an embodiment of the present invention. The socket according to this embodiment comprises a plurality of contacts 110 that provide electrical connection between a semiconductor device such as a BGA (semiconductor package or IC bare chip) and a substrate, a stopper member 120 that aligns and holds the substrate-side contact portions of the contacts 110, a base member 130 that positions and fixes the stopper member 120 and aligns and holds the IC-side ends of the contacts 110, and a cover member 140 that is movable toward or away from the base member 130 and is biased by a coil spring in the direction away from the base member 130. The socket is configured to include a latch member 150 that presses against the upper surface of the semiconductor device to bring the terminals of the semiconductor device into contact with the contacts, a link member 160 that rotates the latch member 150 in conjunction with the movement of the cover member 140, a floating / adapter member 170 that places the semiconductor device on it and guides the ends of the contacts 110 so that the ends of the contacts 110 come into contact with the terminals of the semiconductor device, a guide member 180 that aligns the contact portions of the contacts 110 on the board side, and an insert nut 190 that becomes a female screw when the socket and board are screwed together.

[0014] The configurations and operations of the socket's cover member 140, latch member 150, link member 160, and floating / adapter member 170 are similar to those disclosed in Patent Documents 1 and 2, etc., and detailed description thereof will be omitted. The socket of this embodiment may be configured to accommodate a semiconductor device such as a BGA, and does not necessarily need to include cover member 140, latch member 150, link member 160, and floating / adapter member 170. Although not shown, the socket of this embodiment may include a bias clip that presses the semiconductor device in a certain direction to accurately position the semiconductor device placed on floating / adapter member 170 or base member 130 relative to contact 110. For example, the bias clip presses the semiconductor device diagonally, bringing the semiconductor device into contact with a corner of floating / adapter member 170 or base member 130.

[0015] 9A is a cross-sectional view showing a schematic configuration of the socket of this embodiment. The socket 100 of this embodiment has an interface structure that allows it to be surface-mounted on a circuit board, which makes it possible to mount it on an existing through-hole type circuit board. In a through-hole type board, as shown in FIG. 1B, the socket contacts are soldered to the through holes. However, the socket 100 of this embodiment allows electrical connection of the contacts to the through holes or conductive areas (including conductive pads and wiring) without soldering to the through holes.

[0016] The socket 100 includes a plurality of contacts 110, a stopper member 120 attached within a central opening of a base member 130, and a guide member 180 attached below the stopper member 120. This embodiment further includes a holder 122 between the stopper member 120 and the base member 130, with the holder 122 supporting an upper portion of the wide portion 116A (see FIG. 11 ) of the locking portion 116 of the contact 110, and the stopper member 120 supporting a lower portion of the wide portion 116A of the locking portion 116. However, the holder 122 is not necessarily required, and may be formed integrally with the base member 130 or the stopper member 120, for example.

[0017] FIG. 10A is a plan view of the base member 130, and FIG. 10B is a side view including a partial cross section of the base member 130. A plurality of openings 134 are formed in a matrix in the center of the base member 130. Each opening 134 includes a relatively wide portion 134A and an extending portion 134B extending perpendicularly from the wide portion 134. The extending portion 134B is narrower than the wide portion 134. The openings 134 penetrate the base member and form an internal space partitioned by a plurality of partition walls for aligning and holding a plurality of contacts 110. The contacts 110 are held within the base member 130 with their tips protruding from the wide portion 134A of the openings 134. Cylindrical location pins 200 are provided at the corners of the bottom surface of the base member 130.

[0018] Fig. 11(A) is a front view of the contact, Fig. 11(B) is a side view of the contact, and Fig. 11(C) is an enlarged view of the board-side contact portion. For convenience, the direction of the contact shown in Fig. 11(A) is referred to as the X direction, and the direction of the contact shown in Fig. 11(B) is referred to as the Y direction.

[0019] The contact 110 is formed by stamping or etching a sheet of conductive metal material, such as beryllium copper or a copper alloy. The contact 110 has a generally uniform thickness t in the X direction. The contact 110 extends generally axially, and one end of the contact 110 forms a contact portion 112 that connects to a terminal of a semiconductor device. The contact portion 112 includes a tip portion 112A that contacts a terminal formed on the bottom surface of a BGA package or bare chip, for example, and a protrusion portion 112B that protrudes laterally from the axial direction. The tip portion 112A passes through the wide portion 134A of the opening 134 of the base member 130 and then tilts toward the extended portion 134B. The protrusion portion 112B is fixed upward by the groove in the extended portion 134B, applying a preload to the contact 110.

[0020] A floating / adapter member 170 is disposed on the base member 130, and a through-hole formed in the floating / adapter member 170 is aligned with the position of the opening 134 of the base member 130. The contact portion 112 protruding from the surface of the base member 130 is housed in the through-hole of the floating / adapter member 170. When the floating / adapter member 170 is pressed downward by the latch member 150 via the semiconductor device, the contact portion 112 is guided within the through-hole and protrudes from the surface of the floating / adapter member 170. The cover member 140 is biased in a direction away from the base member 130 by a spring coil 142 (see FIG. 9 ), and the floating / adapter member 170 is linked to the cover member 140 and the latch member 150 via the link member 160. When the cover member 140 is lowered, the latch member 150 opens and the floating / adapter member 170 rises, and when the cover member 140 rises, the latch member 150 closes and the floating / adapter member 170 falls.

[0021] The contact 110 further includes an elastically deforming portion 114 that is bent into a generally U-shape and connected to the contact portion 112 in the X direction. Flexing of the elastically deforming portion 114 applies a constant contact pressure between the contact portion 112 and the terminal of the semiconductor device. The contact 110 further includes a locking portion 116 that extends axially from the elastically deforming portion 114. The locking portion 116 is fixed by a stopper member 120, which will be described later. In one example, the locking portion 116 includes a wide portion 116A that is wider than the wide portion 116A, and the wide portion 116A locks onto the stopper member 120.

[0022] The engaging portion 116 is further connected with a substrate-side contact portion 118 for contacting a conductive region including through holes of the circuit board. The substrate-side contact portion 118 includes an elastic deformation portion 118A bent generally in a U or V shape protruding from the axial direction in the X direction, and a tip portion 118B connected to the elastic deformation portion 118A and extending in the axial direction. The tip portion 118B has a wedge or inverted triangle shape having a width W1 at the root portion and a width W2 at the tip in the Y direction (W1>W2). The side surface connecting the width W1 and the width W2 may be a linear tapered surface or a curved tapered surface.

[0023] FIG. 12 is a diagram for explaining the positional relationship between the substrate-side contact portion and the through hole of the circuit board. As will be described later, when the socket 100 is surface-mounted on the circuit board, the tip portion 118B presses the through hole 214 of the circuit board 210 due to the elastic deformation of the elastic deformation portion 118A. The width W1 of the tip portion 118B of the substrate-side contact portion 118 is larger than the diameter D of the through hole 214, and the width W2 is smaller than the diameter D (W1>D, W2<D). Therefore, when the socket 100 is surface-mounted on the circuit board 210, a part of the tip portion 118B enters the through hole 214, and the side surface of the selection portion 118B contacts the edge of the through hole 214. When plating 212 is formed on the surface of the circuit board 210 and / or the inner wall of the through hole 214, the tip portion 118B contacts the plating 212.

[0024] As described above, a plurality of spaces partitioned by a plurality of partition walls for aligning and holding the plurality of contacts 110 respectively are formed in the base member 130, and the stopper member 120 is attached from the bottom side of the base member 130 so that these spaces are closed (see FIG. 7).

[0025] 13A is a plan view of holder 122, and FIG. 13B is a plan view of stopper member 120. Holder 122 has a generally rectangular shape that is accommodated in the opening of base member 130, and multiple grooves 123 are formed in holder 122. Stopper member 120 has a body portion 121 that is also generally rectangular like holder 122, and multiple grooves 126 are formed in body portion 121 at positions that correspond to grooves 123 of holder 122. Additionally, multiple legs 124 are formed on the sides of body portion 121. Legs 124 are inserted into mounting holes in base member 130 to secure stopper member 120 to base member 130.

[0026] Groove 123 and groove 126 have the same shape and are disposed at a position corresponding to opening 134 of base member 130. As shown in FIG. 13B, groove 126 / 123 includes a slot-shaped extending portion 128A extending laterally, a plurality of extension portions 128B formed at regular intervals on extending portion 128A, and a support portion 128C that supports wide portion 116A of contact 110.

[0027] When assembling the socket, the holder 122 is attached to the opening of the base member 130, and then the contact 110 is inserted into the groove 123 of the holder 122 so that the contact portion 112 (tip portion 112A and protrusion 112B) passes through the extension portion 128B of the groove 123 of the holder 122 and so that the X direction of the contact coincides with the extending direction of the extension portion 128A. The upper portion of the wide portion 116A of the contact 110 is inserted into the support portion 128C, the contact 110 is supported by the holder 122, and the elastic deformation portion 114 is housed in the extension portion 128A.

[0028] Next, the stopper member 120 is attached to the base member 130 so as to be aligned with the holder 122. The tip end 118B of the board-side contact portion 118 of the contact 110 passes through the extended portion 128B of the groove 128 of the stopper member 120, the lower portion of the wide portion 116A is inserted into the support portion 128C, the contact 110 is supported by the stopper member 120, and the elastically deforming portion 118A of the board-side contact portion 118 is housed in the extended portion 128A.

[0029] In this way, a plurality of contacts 110 are arranged in the X direction on one extension portion 128A. The width of the extension portion 128A in the short direction is slightly larger than the thickness t of the contacts 110, and the contacts 110 can move or deform in the X direction within the extension portion 128A.

[0030] The thickness of each of the holder 122 and the stopper member 120 is approximately equal to the axial length of the elastic deformation portion 118A of the board-side contact portion 118. Therefore, the tip portion 118B of the board-side contact portion 118 protrudes from the bottom surface of the stopper member 120.

[0031] A guide member 180 is attached to the base member 130 so as to face the stopper member 120. FIG. 14(A) is a plan view of the guide member 180. As shown in the figure, the guide member 180 includes a main body 182 that provides a rectangular surface and multiple legs 184 formed on the sides of the main body 182. A hook is formed at the tip of each of the multiple legs 184, and the hook engages with a hook 132 formed on the side wall of the base member 130 (see FIG. 9). In a preferred example, the guide member 180 is biased in a direction away from the base member 130 by a spring coil 136 (FIG. 15 shows another cross section to show the spring coil 136), and the guide member 180 can move toward or away from the base member 130. When the legs 184 are engaged with the hooks 132 of the base member 130, the guide member 180 is at a position farthest from the stopper member 120, and a certain distance is formed between them.

[0032] A plurality of through holes 186 are formed in the main body 182 of the guide member 180 at positions that align with the grooves 126 of the stopper member 120. The through holes 186 are rectangular grooves whose diameter narrows from the surface to the bottom surface of the guide member 180, but the shapes of the through holes 186 differ in the longitudinal and lateral directions.

[0033] 14(B) is a cross-sectional view of through-hole 186 taken along line XX, and FIG. 14(C) is a cross-sectional view of through-hole 186 taken along line YY. As shown in FIG. 14(B), the shape of through-hole 186 in the X direction is asymmetrical, with one inclined surface S1 having a larger inclination angle (angle formed with the horizontal) than the other opposing inclined surface S2, and inclined surfaces S1 and S2 are connected to vertical surfaces S3 and S4 of width d1. On the other hand, the shape of through-hole 186 in the Y direction is symmetrical, with one inclined surface S5 having the same inclination angle as the other opposing inclined surface S6, and inclined surfaces S5 and S6 are connected to vertical surfaces S7 and S8 of width d2 (d1 <d2)。

[0034] 9, the contacts 110 are arranged on the base member 130 so that their orientations in the X direction are reversed left and right. Accordingly, the through-holes 186 of the guide member 180 have the inclined surface S1 of the through-hole 186A in the left half of the socket positioned on the left side, and the through-hole 186B in the right half positioned on the right side.

[0035] Tip 118B protruding from the bottom surface of stopper member 120 is inserted into through-hole 186 of guide member 180. When guide member 180 is at the farthest position from base member 130, tip 118B is at a position approximately flush with the bottom surface of guide member 180 or protrudes slightly beyond the bottom surface. The amount of this protrusion can be adjusted depending on the position of guide member 180 when it is farthest from base member 130.

[0036] 9(B) shows a state when the X-direction tip 118B has entered the through-hole 186, and FIG. 9(C) shows a state when the Y-direction tip 118B has entered the through-hole 186. Sloped surfaces S1, S2, S5, and S6 on the upper surface side of the through-hole 186 function as guides for guiding the tip 118B into the through-hole 186. The width d1 of the bottom surface of the through-hole 186 in the X direction is slightly larger than the plate thickness t of the contact 110, and the width d2 of the bottom surface of the through-hole 186 in the Y direction is slightly larger than the width W1 of the tip 118B.

[0037] Next, the operation of attaching the socket of this embodiment to a board will be described. First, the location pins 200 protruding from the corners of the bottom surface of the base member 130 are inserted into the positioning holes 216 in the circuit board 210, and the socket 100 is positioned on the circuit board 210. FIG. 15 shows this state. Also, FIGS. 17(A1) and 17(A2) show the positional relationship between the tip portion 118B and the through-hole 214 in the circuit board 210. The tip portion 118B protrudes slightly from the bottom surface of the guide member 180, and is positioned so that this protruding portion faces the through-hole 214. In other words, the axial direction of the board-side contact portion 118 roughly coincides with the axial center of the through-hole 214 in the circuit board 210.

[0038] Next, while pressing socket 100 against circuit board 210, the socket is fixed with screws 220 from the back side of the circuit board (see FIG. 8). This pressing force causes guide member 180 to move toward stopper member 120 against spring member 136, and eventually guide member 180 abuts against stopper member 120. As guide member 180 moves upward, tip portions 118B of contacts 110 protrude further from the bottom surface of guide member 180. FIG. 16 shows this state.

[0039] During the process of pressing the socket 100 against the circuit board 210, the Y-direction side of the tip 118B comes into contact with the edge of the through-hole 214, and the board-side contact portion 118 receives an axial reaction force from the surface of the board. This causes the elastic deformation portion 118A to elastically deform, and the X-direction tip 118B tilts as shown in FIG. 17(B1). Because the inclination angle of the inclined surface S1 of the through-hole 186 of the guide member 180 is large, the tip 118B tilts without interfering with the inclined surface S1. In one embodiment, by appropriately selecting the inclination angle of the inclined surface S1, the angle at which the tip 118B tilts can be restricted by bringing the tip 118B into contact with the inclined surface S1, thereby ensuring that the tip 118B wipes against the edge portion WP.

[0040] When Y-direction tip 118B enters through-hole 214 in the axial direction, its side contacts and wipes edge portion WP of through-hole 214. At the same time, X-direction tip 118B is tilted, causing the side of tip 118B to further wipe the edge portion. In this way, tip 118B removes foreign matter adhering to the edge portion of through-hole 214, thereby achieving a good electrical connection with through-hole 214.

[0041] Thereafter, as described above, the socket 100 and the substrate 210 are fixed together with the screws 220. After the socket 100 has been surface mounted, it is subjected to a burn-in test and the like in the same manner as a normal socket.

[0042] As described above, according to this embodiment, the axial direction of contact 110 is aligned with the axial center of through-hole 214, and then wedge-shaped tip 118B is inserted into through-hole 214. This eliminates the need for a curved portion that protrudes laterally from the axial direction at the board-side contact point, as in conventional sockets, allowing the contacts to be arranged at a narrow pitch. Furthermore, by inserting tip 118B axially into the through-hole and wiping the edge of the through-hole, an electrical connection with the through-hole via multiple contacts can be obtained.

[0043] 18 is a diagram showing the configuration of a contact according to another embodiment of the present invention. In the previous embodiment, tip portion 118B of board-side contact portion 118 has a wedge shape as shown in FIG. 11(C). However, in this embodiment, tip portion 118B further includes extension portion 118C that extends a certain length with width W2. The length of extension portion 118C is adjusted so that board-side contact portion 118B can wipe the inner wall of through-hole 214 when tilted.

[0044] 17(A1) and (A2), when socket 100 is placed on circuit board 210, extension portion 118C of board-side contact portion 118 penetrates further into through-hole 214 of circuit board 210. Next, when socket 100 is pressed against circuit board 210 and guide member 190 approaches base member 130, wedge-shaped tip portion 118B comes into contact with edge portion WP and wipes edge portion WP, as shown in FIGS. 18(B1) and (B2), and extension portion 118C comes into contact with inner wall portion WP1 of through-hole 214 and wipes inner wall portion WP1.

[0045] Thus, according to another embodiment, by providing an extension portion 118C on the board-side contact portion 118, the board-side contact portion 118 can be wiped with the edge portion WP and inner wall portion WP1 of the through-hole 214, and multiple contacts can be increased, thereby obtaining a good electrical connection between the socket and the circuit board.

[0046] Furthermore, this embodiment has the following effects. Surface mount sockets can be used on existing through-hole type boards, and mixed mounting is also possible. -Since the component configuration is almost the same as that of existing through-hole type sockets, it is cheaper than probe pin type surface mount sockets. · The tip of the contact is formed by stamping only, so it can be applied regardless of IC pitch. The following measures can prevent poor contact caused by foreign objects, which was a conventional problem. a. Two points of contact with the edge of the through-hole are made, accompanied by wiping. b. The tip of the contact part on the board side is inserted into the through hole, so contact is not hindered by foreign matter on the pad as in the past. c. The tip of the board-side contact part is arrowhead-shaped, and the inclined part of the through-hole of the guide member acts as a guide for the tip to be inserted into the through-hole reliably. d. The base of the arrowhead shape of the tip is larger than the diameter of the through-hole, and the plate thickness t is smaller than the diameter of the through-hole, so that when the tip is inserted into the through-hole, the slopes on both sides of the tip wipe the edge of the through-hole. e.The spring parts on the IC side and board side move independently.

[0047] In the above embodiment, the tip 118B of the board-side contact portion 118 is wedge-shaped or inverted triangular, but the tip 118B is not limited to such a shape. The tip 118B should have at least a portion narrower than the diameter D of the through-hole and a portion wider than the diameter D, and should have a linear or curved tapered portion between the narrow and wide portions that can wipe the edge of the through-hole. For example, the tip may be barrel-shaped.

[0048] In the above embodiment, the tip 118B is inserted into a through-hole in a circuit board, but the tip 118B may be brought into contact with a conductive area other than a through-hole. For example, a conductive area including an opening or recess may be formed on the circuit board, and the tip 118B may be brought into contact with such an opening or recess to perform wiping.

[0049] The circuit board on which the socket is mounted may be either a board with a single-layer wiring structure or a board with a multi-layer wiring structure. The shape and material of the conductive region formed in the through-hole of the board are not particularly limited, as long as the board-side contact portion 118C can be electrically connected to the conductive region when it comes into contact with the through-hole of the board.

[0050] Furthermore, the semiconductor device mounted in the socket is not particularly limited. In the above embodiment, a BGA package with solder balls was used, but other surface-mount semiconductor packages (semiconductor devices) may also be used. Furthermore, the shape of the terminals is not limited to spherical, and may be semicircular, conical, rectangular, or other bump shapes.

[0051] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and variations are possible within the scope of the gist of the present invention as set forth in the claims. [Explanation of symbols]

[0052] 100: Socket 110:Contact 112: Contact point 114: Elastic deformation part 116: Locking part 118: Board side contact part 118A: Elastic deformation part 118B:Tip 120: Stopper member 122: Holder component 130: Base material 140: Cover member 180: Guide member 210: Substrate 214:Through hole

Claims

1. A socket that can be surface mounted on a substrate, a plurality of contacts made of a plate-like conductive material, each contact including a contact portion capable of contacting a terminal of a semiconductor device, a locking portion connected to the contact portion, and a substrate-side contact portion extending from the locking portion and capable of contacting a conductive region including an opening formed on a substrate, the substrate-side contact portion including an elastically deformable portion connected to the locking portion and a tip portion connected to the elastically deformable portion; a holding member for holding the locking portions of the plurality of contacts; a guide member that is movable in a direction toward or away from the holding member and has a plurality of through holes formed therein into which the board-side contact portions protruding from the holding member are inserted; the tip portion has a first end portion located on the elastically deforming portion side and a second end portion located on the opposite side to the elastically deforming portion, a width of the first end greater than a diameter of the opening, and a width of the second end less than a diameter of the opening; When the guide member is moved in a direction approaching the holding member, the tip portion enters the opening from the second end, and the connection area between the first end and the second end contacts the edge portion of the opening, and the elastic deformation portion elastically deforms, causing the tip portion to tilt while the connection area contacts the edge portion of the opening, wiping the edge portion of the opening.

2. 2. The socket of claim 1, wherein the contact has a generally constant thickness in a first direction, the elastic deformation portion protrudes from the axial direction in the first direction, and the width of the first end and the second end of the tip portion is a length in a second direction perpendicular to the first direction.

3. 3. The socket according to claim 1, wherein the connection area is linearly or curvedly sloped.

4. 4. The socket according to claim 1, wherein the tip portion has a wedge or inverted triangle shape.

5. 5. The socket according to claim 1, wherein when said guide member is at a position spaced apart from said holding member, a part of said tip portion is located at a position facing the opening of said circuit board.

6. A socket described in any one of claims 1 to 5, wherein when the connection region contacts the edge portion of the opening, the tip portion is subjected to an axial force and tilts in a certain direction due to elastic deformation of the elastic deformation portion.

7. The socket according to claim 6 , wherein the through hole of the guide member is formed with an inclined surface for allowing the tip portion to be inclined.

8. 8. The socket according to claim 1, wherein the tip portion further includes an extension portion extending axially from the second end portion, the extension portion extending into the opening when the guide member is in a position spaced apart from the retaining member.

9. The socket according to claim 8 , wherein when the guide member moves in a direction approaching the holding member, the connection region wipes the edge portion of the opening and the extension portion wipes the inner wall portion of the opening.

10. 10. The socket according to claim 1, wherein the opening is a through hole.

11. 2. The socket of claim 1, further comprising spring means for biasing said guide member in a direction away from said holding member.

12. 12. A mounting device comprising: the socket according to claim 1; and a circuit board on which the socket is surface-mounted.

13. The socket according to claim 12 , wherein the mounting device is a test device.

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