US20010050427A1 - Test soket of semiconductor device - Google Patents
Test soket of semiconductor device Download PDFInfo
- Publication number
- US20010050427A1 US20010050427A1 US09/839,239 US83923901A US2001050427A1 US 20010050427 A1 US20010050427 A1 US 20010050427A1 US 83923901 A US83923901 A US 83923901A US 2001050427 A1 US2001050427 A1 US 2001050427A1
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- US
- United States
- Prior art keywords
- contact
- blade
- semiconductor device
- test socket
- positioning
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/02—General constructional details
- G01R1/04—Housings; Supporting members; Arrangements of terminals
- G01R1/0408—Test fixtures or contact fields; Connectors or connecting adaptors; Test clips; Test sockets
- G01R1/0433—Sockets for IC's or transistors
- G01R1/0483—Sockets for un-leaded IC's having matrix type contact fields, e.g. BGA or PGA devices; Sockets for unpackaged, naked chips
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/02—General constructional details
- G01R1/04—Housings; Supporting members; Arrangements of terminals
- G01R1/0408—Test fixtures or contact fields; Connectors or connecting adaptors; Test clips; Test sockets
- G01R1/0433—Sockets for IC's or transistors
- G01R1/0441—Details
- G01R1/0466—Details concerning contact pieces or mechanical details, e.g. hinges or cams; Shielding
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
Definitions
- the present invention relates to a test socket of a semiconductor device to be used, for example, to connect a semiconductor package having a ball-shaped external terminal projected from the package bottom to test equipment.
- FIGS. 1 to 3 A conventional test socket of a semiconductor device will be explained by referring to FIGS. 1 to 3 .
- FIG. 1 is a cross sectional view showing a basic constitution of a contact member 1 of a spring probe pin type test socket.
- the spring probe pin type test socket is a test socket for executing a characteristic evaluation test of, for example, an FBGA (flat package ball grid array) IC (integrated circuit) 2 in which many contact members 1 are installed in the test socket.
- FBGA flat package ball grid array
- IC integrated circuit
- Each of these contact members 1 is structured so as to receive a ball-shaped external terminal 3 made of solder projecting from a bottom of a package of IC 2 with a concavity at an upper end thereof being supported by a pin support member not shown in the drawing.
- the lower end thereof is in contact with a contact pad 5 of a test board 4 corresponding to the external terminal 3 of the IC 2 .
- External terminal 3 and pad 5 are thus connected to be conductible to each other, thereby DC characteristic evaluation or AC characteristic evaluation such as the high frequency characteristics and high-speed characteristics are carried out.
- the contact member 1 has a metallic cylindrical case 6 with an upper end closed, a compression spring 7 housed in the case 6 for generating compression force in the axial direction, and a contact end 8 projecting downward from a lower end opening of the case 6 .
- An upper end of the contact end 8 is connected to a metallic plunger 9 , which is compressed by the spring 7 in the cylindrical case 6 .
- a concavity 10 is formed at the upper end of the case 6 .
- the characteristic evaluation test of the IC 2 is executed under the condition that the external terminal 3 on the bottom of the IC 2 is pressed against the upper end concavity 10 of the contact member 1 installed to the test socket and that the contact end 8 of the plunger 9 projected downward is pressed against the contact pad 5 of the test board 4 of the test equipment at the same time.
- the contact member 1 of the spring probe pin type test socket has a line length of, for example, 3 to 5 mm and has an inductance of 1 nH to 1.5 nH or so due to the structure in which the upper end concavity 10 and the contact end 8 are respectively pressed against the corresponding external terminal 3 and contact pad 5 so as to conduct to each other by the plunger 9 compressed by the spring 7 housed in the case 6 and connected.
- the line length must be shorter.
- a test socket for high frequency having a short line length and low inductance must be used which means a replacement of the test socket.
- FIG. 2 is a cross sectional view showing a basic structure of a contact member 11 of a sheet type test socket.
- the contact member 11 is a test socket for executing the characteristic evaluation test of the IC 2 of the FBGA type described above, which is structured so that many metallic wires 13 are embedded overall a sheet-like insulating base 12 at a fine pitch and are inclined to a surface of the sheet.
- the contact member 11 of the test socket is arranged between the IC 2 and the test board 4 of the test equipment.
- the external terminal 3 of the IC 2 and the corresponding contact pad 5 of the test board 4 are arranged facing to each other across the contact member 11 . Thereafter, the external terminal 3 and the contact pad 5 are pressed against the contact member 11 .
- a part of the wires 13 obliquely embedded in the insulating base 12 and in contact with the external terminal 3 are also in contact with the contact pad 5 and thereby being made conductive to each other.
- the length of the oblique metallic wires 13 is about 1.1 mm when the thickness of the insulating base 12 is about 1 mm, for example, which is shorter than that of the first prior art and the inductance is 0.2 nH or less, which is also lower than that of the first prior art.
- solder dust or package dust adhered on the surface of the external terminal 3 is also adhered on the surface of the contact member 11 in contact with the external terminal 3 of the IC 2 when the IC 2 characteristic evaluation test is executed many times.
- the adhered dust remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, whenever the contact count reaches about 1500 times, for example, the contact member 11 must be frequently cleaned for which a great deal of time is required.
- the cost is very high due to the structure of the contact member 11 in which the metallic wires 13 are arranged regularly overall the insulating base 12 .
- FIG. 3 is a cross sectional view showing the basic structure of a contact member 14 of a sheet type test socket for executing the characteristic evaluation test of the IC 2 of FBGA described above.
- the contact member 14 holds many conductive elastic contactors 16 at a position corresponding to the external terminal 3 on the bottom of the package of IC 2 of the sheet-like insulating base 15 .
- Each of the elastic contactors 16 is formed passing through the insulating base 15 and having an upper contact part 16 a and a lower contact part 16 b respectively projected from an upper and a lower surface of the insulating base 15 .
- the contact member 14 of the test socket is arranged between the IC 2 , so that the test board 4 of the test equipment and the contact surface of the lower contact part 16 b of the elastic contactor 16 is positioned right above the contact pad 5 of the test board 4 . Further, the corresponding the external terminal 3 of the IC 2 is positioned right above the contact surface of the upper contact part 16 a of the elastic contactor 16 .
- the external terminal 3 is pressed against the contact surface of the upper contact part 16 a of the elastic contactor 16 installed on the contact member 14 and the contact surface of the lower contact part 16 b of the elastic contactors 16 is pressed against the top of the contact pad 5 of the test board 4 .
- the external terminal 3 and the contact pad 5 are made conductive to each other via the elastic contactor 16 .
- the line length is selected as about 0.7 mm, for example, in the contact member 14 of the test socket having the structure described, it is shorter than that of the second prior art having such a low inductance as 1.0 nH. As a result, characteristics at a higher frequency than that of the second prior art can be evaluated.
- solder dust or package dust adhered on the surface of the external terminal 3 is also adhered on the surface of the elastic contactor 16 of the contact member 14 in contact with the external terminal 3 of the IC when the IC 2 characteristic evaluation test is executed many times.
- the adhered dust remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, whenever the contact count reaches about 1500 times, for example, the contact member 14 must be frequently cleaned for which a great deal of time is required.
- the present invention was made under the circumstance described above and has an object to provide a test socket for a semiconductor device which enables the high frequency characteristics evaluation satisfactorily, requires shorter time for cleaning and is easy to handle.
- test socket for a semiconductor device having contact members which lie between ball-shaped external terminals projected from a surface of the semiconductor device and contact pads of the semiconductor test circuit to make them conductive to each other wherein each of said contact member comprises blade-shaped contact members in contact with one of said external terminals, a positioning member for positioning said blade-shaped contact members having positioning holes into which said blade-shaped contact members are inserted, and a conductive elastic contactor having a top portion which is in contact with said blade-shaped contact member positioned by said positioning member and a bottom portion of which is in contact with one of said contact pads.
- the blade-shaped contact members have a plurality of blades arranged so that their outer surfaces form a circular surface and that ridgelines of the blades become gradually low from the outer peripheral surfaces of the circular arrangement toward the center thereof and intersect each other at a bottom part.
- the blade-shaped contact member has a flange formed at its bottom which engages a lower surface of the positioning member and prevents the blade-shaped contact member from being get out of the positioning holes upward, when they are inserted into the positioning holes of the positioning members.
- the blade-shaped contact member has a substantially flat bottom surface, which is in contact with a top of the elastic contactors.
- the blade-shaped contact members are installed so as to be removable from the elastic contactors.
- the elastic contactors are made of a conductive resin and are embedded in an insulating base at a predetermined pitch.
- the insulating base supports the elastic contactors so that both ends thereof are projected from upper and lower surfaces of the insulating base.
- either one of the bottom of the blade-shaped contact member and the top of the elastic contactor has either one of a convexity and concavity so that they are fit into each other.
- the positioning members having the positioning openings position the contact members and elastic contactors for the external terminals and contact pads.
- test socket for a semiconductor device having contact members which lie between a plurality of ball-shaped external terminals projected from a surface of the semiconductor device and contact pads of the semiconductor test circuit to make them conductive to each other wherein each of said contact member comprises blade-shaped contact members in contact with one of said external terminals, a positioning member for holding the blade-shaped contact members, and a plurality of conductive elastic contactors having a top portion which is in contact with one of said blade-shaped contact members positioned by said positioning member and a bottom portion of which is in contact with one of said contact pads.
- the blade-shaped contact members have a plurality of blades arranged so that their outer surfaces form a circular surface and that ridgelines of the blades become gradually low from the outer peripheral surfaces of the circular arrangement toward the center thereof and intersect each other at a bottom part.
- a plurality of positioning holes are formed in the positioning members and the blade-shaped contact member has a flange formed at its bottom which engages a lower surface of the positioning member and prevents the blade-shaped contact member from being get out of the positioning holes upward, when they are inserted into the positioning holes of the positioning members.
- the blade-shaped contact member has a substantially flat bottom surface, which is in contact with a top of the elastic contactors.
- the elastic contactors are made of a conductive resin and are embedded in an insulating base at a predetermined pitch.
- the test socket for a semiconductor device comprises a frame plate having a space for housing the semiconductor device at a center portion thereof, a positioning member in contact with a bottom surface of the frame plate which is arranged so that a part of an upper surface thereof is exposed in the space for housing the semiconductor device, a plurality of blade-shaped contact members fixedly received in a plurality of positioning holes formed in the positioning member, an insulating base arranged so as to be in contact with a bottom surface of the positioning member, a plurality of elastic contactors embedded in an insulating base at a predetermined pitch, and a board arranged in contact with a bottom surface of the insulating base on which the semiconductor test circuit is formed.
- positioning pins are fixed to the frame plate penetrating through the positioning member, insulating base, and the board on which the semiconductor test circuit are formed.
- FIG. 1 is a cross sectional view showing the basic structure of a conventional test socket for a semiconductor device.
- FIG. 2 is a cross sectional view showing the basic structure of a conventional test socket for a semiconductor device.
- FIG. 3 is a cross sectional view showing the basic structure of a conventional test socket for a conventional semiconductor device.
- FIG. 4 is a cross sectional view showing the basic structure of the test socket for a semiconductor device according to a first embodiment of the present invention.
- FIG. 5 is a partial cross sectional view of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 6 is an enlarged view of the essential section of the test socket for a semiconductor device according to the present invention.
- FIG. 7 is an enlarged view of the essential section of the test socket for a semiconductor device according to the present invention.
- FIG. 8 is a cross sectional view showing a modified example of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 9 is a partial cross sectional view showing a modified example of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 10 is a cross sectional view showing the basic structure of the test socket for a semiconductor device according to a second embodiment of the present invention.
- FIG. 11 is a cross sectional view showing a part of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 12 is a cross sectional view showing a modified example of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 13 is a partial cross sectional view showing a modified example of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 14 is a top view of the test socket for a semiconductor device according to a third embodiment of the present invention.
- FIG. 15 is a cross sectional view showing a part of the test socket for a semiconductor device according to the third embodiment of the present invention.
- FIG. 4 is a cross sectional view showing the basic structure of the test socket of the semiconductor device according to the present invention and FIG. 5 is a cross sectional view showing the essential section thereof.
- FIGS. 6 and 7 are enlarged views of a part of FIG. 4.
- a test socket 21 is a test socket for executing a characteristic evaluation test of an IC (integrated circuit) 22 of a FBGA (flat package ball array).
- the test socket 21 is attached to the IC 22 and then mounted to a test board 23 of the test equipment, thereby the test for characteristic evaluation is executed.
- a plurality of external terminals 25 made of ball-shaped solder is projected at a predetermined pitch on the bottom of a package 24 .
- gold-plated contact pads 26 made of a copper material are mounted corresponding to the external terminals 25 of the IC 22 at a predetermined pitch.
- the test socket 21 has a contact member 30 having an elastic contactor 28 mounted on a sheet-like.
- An upper contact part 28 a and a lower contact part 28 b of the elastic contactor 28 are projected from the top and bottom surfaces of the insulating base 27 .
- a metallic blade-shaped contact member 29 is provided in a removable state so as to cover the upper contact part 28 a of the elastic contactor 28 .
- the contact member 30 thus formed, is provided lying between the external terminates 25 of the IC 22 and the contact pads 26 of the test boards 23 , so that the corresponding external terminals and the contact pads are made conducted to each other.
- FIG. 6 is a drawing showing the structure of a blade-shaped contact member 29 , and (A) is a top view, and (B) is a side view.
- FIG. 7 is also a drawing showing the structure of the blade-shaped contact member 29 , though it is a drawing viewed at a different angle from that shown in FIG. 6.
- the blade-shaped contact member 29 has four contact blades 29 - 1 , 29 - 2 , 29 - 3 , and 29 - 4 , each of which forms an arc outer peripheral surface in the top view.
- the four contact blades 29 - 1 , 29 - 2 , 29 - 3 , and 29 - 4 are arranged so that the whole outer thereof are almost circular as shown in the top view (A). Inside the circular peripheral surfaces, ridges of the blades 29 - 1 , 29 - 2 , 29 - 3 , and 29 - 4 descend by a gradual slope from the circular outer peripheral surface toward a center portion thereof and intersect each other at the center portion.
- the blade-shaped contact member 29 is made of, for example, beryllium copper having a gold-plated surface.
- An upper end of the contact member 29 is in contact with the surface of the ball-shaped external terminals 25 of the IC 22 via the ridges of the contact blades 29 - 1 , 29 - 2 , 29 - 3 , and 29 - 4 , and thus one of the contact members 29 and the corresponding external terminal 25 are made conductive to each other.
- the blade-shaped contact members 29 were explained as each having four contact blades 29 - 1 , 29 - 2 , 29 - 3 , and 29 - 4 .
- the number of contact blades is not limited to 4 and may be any number more than one.
- the insulating base 27 included in the contact member 30 is made of, for example, a polyimide resin film, which allows little deformation in size and has a high heat resistance.
- mounting holes 31 for mounting the elastic contactors 28 are formed at positions corresponding to the locations of the external terminals 25 of the IC 22 .
- the elastic contactor 28 is made of, for example, synthetic rubber such as conductive silicone rubber, natural rubber, or flexible synthetic resin with carbon, metallic powder, or metal filler mixed.
- An upper contact part 28 a and a lower contact part 28 b having a shape of truncated cone the diameter of which is larger than that of a mounting hole 31 are formed on both end sides of the elastic contactor 28 .
- An intermediate part 28 c of the elastic contactor 28 is inserted in the mounting hole 31 , thereby fixing the elastic contactor 28 to the insulating base 27 .
- a concavity 33 with a larger diameter than that of the upper contact part 28 a of the elastic contactor 28 is formed at the end of the blade-shaped contact member 29 on the side of the test board 23 .
- a conic concavity 34 is further formed in the concavity 33 .
- a flange 35 is provided extending outward at the end of the blade-shaped contact member 29 on the side of the test board 23 .
- the test socket 21 has an upper positioning member 36 and a lower positioning member 37 with a predetermined thickness and predetermined hardness for supporting and positioning the contact member 30 at the time of test.
- the upper positioning member 36 and the lower positioning member 37 are made of such an insulating material as a synthetic resin including epoxy resin filled with glass filler, PAT (polyamide-imide), or PES (polyether sulfide), for example.
- the upper positioning member 36 is placed on the insulating base 27 to position the contact member 29 as well as to support the IC 22 at the time of test.
- the upper positioning member 36 has a plurality of upper positioning holes 39 in which the blade-shaped contact members 29 are inserted.
- a step portion 38 is formed on the lower sidewall of the upper positioning holes 39 to form a lower part with a large diameter.
- the upper positioning hole 39 positions the contact member 29 in the transverse direction and engages the flange 35 of the blade-shaped contact member 29 with the step portion 38 so as to prevent it from getting out of the upper positioning hole 39 .
- the thickness of the upper positioning member 36 is appropriately selected within a range of elastic deformation of the upper contact part 28 a of the elastic contactor 28 , so that even when the upper contact part 28 a is deformed until the external terminal 25 is brought in contact with the four blades of the blade-shaped contact member 29 by pressing the IC 22 downward, and the bottom of the package 24 of the IC 22 touches the top of the upper positioning member 36 , a pressure for making a contact between the external terminal 25 and the four blades of the blade-shaped contact member 29 is set to a required value.
- the lower positioning contactor 37 positions the elastic contactor 28 placed on the contact pad 26 of the test board 23 as well as supports the insulating base 27 , the upper positioning member 36 and the IC 22 , which are placed on it at the time of test.
- Lower positioning holes 40 are formed in the lower positioning contactor 37 in which the lower contact parts 28 b of the elastic contactor 28 are inserted.
- the lower positioning holes 40 position the lower contact parts 28 b of the elastic contactor 28 in the transverse direction, thereby controlling the position of the insulating base 27 to which the elastic contactor 28 is mounted in the transverse direction.
- the thickness of the lower positioning member 37 is appropriately selected within the range of the elastic deformation of the lower contact part 28 b of the elastic contactor 28 , thereby making the pressing force between the elastic contactor 28 and the contact pad 26 is set to a required value.
- the contact member 30 in which the upper contact parts 28 a of the elastic contactor 28 mounted on the insulating base 27 are covered respectively by the contact members 29 is combined with the lower positioning members 37 by inserting the lower contact parts 28 b into the corresponding lower positioning holes 40 .
- the contact members 29 are then inserted into the corresponding upper positioning holes 39 , and the upper positioning members 36 are located on the insulating base 27 so that the step portion 38 is put on the flange 35 , thereby constructing the test socket 21 .
- the IC 22 is set in the test socket 21 so that the external terminals 25 are in contact with the concavities 32 of the contact members 29 in the corresponding upper positioning holes 39 . Then, the test socket 21 is put on the test board 2 of the test equipment, and the IC 22 set in the test socket 21 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing.
- the upper contact parts 28 a are deformed until the bottom of the package 24 of the IC 22 touches the top of the upper positioning members 36 .
- the lower contact parts 28 b is elastically deformed until the insulating base 27 touches the top of the lower positioning members 37 and the height of the lower contact parts 28 b of the elastic contactors 28 reaches the thickness of the lower positioning members 37 .
- the bottom of the lower contact parts 28 b is thus in contact with the contact pads 26 of the test board 23 with predetermined compression force and the external terminals 25 of the IC 22 are made conductive to the corresponding contact pads 26 of the test board 23 .
- the line length of the test socket 21 becomes, for example, 1 mm or less and the inductance becomes 0.5 nH or less.
- the line length of the test socket 21 can be shortened and the inductance can be lowered to less than 0.5 nH, so that the characteristics at a high frequency of several GHz can be evaluated.
- the blade-shaped contact members 29 are pressed to the ball-shaped external terminals 25 of the IC 22 with a long contact length of blades of the blade-shaped contact members 29 with little contact resistance.
- the contact members 29 are in contact with the external terminals 25 via a metallic blades, so that the contact members 29 are hardly affected by, for example, solder dust or package dust attached to the surface of the external terminals 25 and the characteristic evaluation test can be executed in a comparatively satisfactory state. Even when the characteristic evaluation test is continued further, the problems in the prior art is resolved that the adhered dust is remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, the necessity of cleaning is reduced remarkably, and a great deal of time for cleaning is not required.
- the ends of the contact members 29 on the side of the IC 22 are of the blade-shaped shape so as to make the contact length of the external terminals 25 with the contact members 29 longer.
- a pin shape may be applied so as to scratch the surface of the external terminals 25 and to realize a sure contact.
- the shape of the compressing structure between the contact members 29 and the elastic contactors 28 may be modified.
- the inner bottoms of the concavities of the contact members 29 are conic concavities 34 to make the stroke length at the contact portions of the upper contact parts 28 a longer.
- the inner bottoms of the concavities of the contact members 29 may be concavities having a curved surface such a spherical surface and furthermore, they may be conic projections or projections having a curved surface such a spherical surface.
- the concavities may be deformed as shown in FIGS. 8 and 9.
- the inner bottoms of concavities 133 of contact members 129 are a flat surface.
- the flat upper end surfaces of the upper contact parts 28 a of the elastic contactors 28 are in contact with the inner bottoms of the concavities 133 , and the elastic deformation amount of the upper contact parts 28 a is reduced under the same compression force, and thus the stroke length can be shortened. Even in the deformed structure thus formed, the same effect as that of the first embodiment can be obtained.
- FIG. 10 is a cross sectional view showing a basic structure of the test socket for a semiconductor device according to the present invention
- FIG. 11 is a cross sectional view of an partial section thereof.
- FIG. 12 shows a structure shown in FIGS. 10 and 11, which is slightly deformed. The same numeral is assigned to each of the same parts as those in the first embodiment, and the explanation thereof is omitted. The parts of the embodiment different from those of the first embodiment will be explained bellow.
- a test socket 41 is used to mount the IC 22 on the test board 23 and evaluate the characteristics thereof.
- elastic contactors 43 are berried in an elastic laminar insulating base 42 so that upper contact end faces 43 a and lower contact end faces 43 b are exposed on the top and bottom surfaces of the elastic laminar insulating base 42 .
- metallic blade-shaped contact members 44 in contact with the upper contact end faces 43 a of the elastic contactors 43 are mounted in a removable state and the elastic contactors 43 and the blade-shaped contact members 44 constitute a contact member 45 .
- the contact member 45 lies between the external terminals 25 of the IC 22 and the contact pads 26 of the test board 23 , thereby making them in conductive to each other.
- the insulating base 42 and the elastic contactors 43 of the contact member 45 are of pillar-like shape and are made of, for example, synthetic rubber such as silicone rubber, or natural rubber, or flexible synthetic resin, which are made conductive by being mixed with, for example, carbon, metallic powder, or metal filler.
- the elastic contactors 43 are fit into holes 46 formed in the corresponding portions to the external terminals 25 of the IC 22 of the insulating base 42 and integrated with the insulating base 42 and the elastic contactors 43 and the insulating base 42 form a so-called zebra connector.
- the blade-shaped contact members 44 are made of, for example, beryllium copper having a gold-plated surface and have a structure shown in FIGS. 6 and 7.
- the ends of the blade-shaped contact members 44 on the side of the IC 22 are, as described above, in contact with the ball-shaped external terminals 25 at the four blade-shaped ridges and are made conductive with the ball-shaped external terminals 25 .
- convexities 47 are formed on the end of the blade-shaped contact members 44 on the side of the test board 23 , which has such a curved surface as an almost spherical surface in contact with the upper contact end faces 43 a of the elastic contactors 43 . Furthermore, at the intermediate portion of the blade-shaped contact members 44 , the flanges 35 project outward. When the blade-shaped contact members 44 come in contact with the upper contact end faces 43 a of the elastic contactors 43 with being compressed to each other, the elastic contactors 43 begin deforming at the portions where the convexities 47 of the blade-shaped contact members 44 come in contact, thereby being made conductive with each other.
- the test socket 41 has positioning members 48 with a predetermined thickness and hardness for supporting and positioning the contact member 45 at the time of test.
- the positioning members 48 are made of such an insulating material as a synthetic resin including epoxy resin filled with glass filler, PAI (polyamide-imide), or PES (polyether sulfide), for example.
- the positioning member 48 is placed on the insulating base 42 for supporting the IC 22 and has positioning holes 49 for positioning the blade-shaped contact members 44 by being inserted in the positioning holes 49 at the time of test.
- the positioning holes 49 position the blade-shaped contact members 44 in the transverse direction and press the flanges 35 of the blade-shaped contact members 44 at the bottom of the positioning members 48 so as to prevent them from getting out of the positioning holes 49 .
- the thickness of the positioning members 48 is so selected that the four blades of the blade-shaped contact members 44 are in contact with the external terminals 25 at predetermined pressure caused by the deformation of the elastic contactors 43 within the range of the elastic deformation when IC 22 is compressed downward.
- the contact members 44 are put on the respective upper contact end faces 43 a of the elastic contactors 43 berried in the insulating base 42 , in such a manner that the respective convexities 47 come in contact with the respective upper contact end faces 43 a of the elastic contactors 43 .
- the positioning members 48 are then placed over the blade-shaped contact members 44 so that each of blade-shaped contact members 44 may be inserted into each of the positioning holes 49 and that the positioning members 48 are may be put on the flanges 35 .
- the IC 22 is mounted in the test socket 41 so that the external terminals 25 may touch the corresponding blade-shaped contact members 44 in the positioning holes 48 .
- the test socket 41 is put on the test board 23 of the test equipment, and the IC 22 mounted in the test socket 41 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing.
- the upper contact end faces 43 a of the elastic contactors 43 are elastically deformed until the external terminals 25 on the bottom of the package 24 of the IC 22 touch the top of the blade-shaped contact members 44 .
- the lower contact end faces 43 b are thus in contact with the contact pads 26 of the test board 23 with predetermined pressure and the external terminals 25 of the IC 22 and the corresponding contact pads 26 of the test board 23 are made conductive with each other.
- the line length of the test socket 41 becomes, for example, 1 mm or less and the inductance is 0.5 nH or less, which is the same as that of the first embodiment.
- the line length of the test socket 21 can be shortened and the inductance can be lowered to less than 0.5 nH, so that the characteristics at a high frequency of several GHz can be evaluated.
- the blade-shaped contact members 29 are pressed to the ball-shaped external terminals 25 of the IC 22 with a long contact length of blades of the blade-shaped contact members 29 with little contact resistance.
- the contact members 29 are hardly affected by, for example, solder dust or package dust adhered to the surface of the external terminals 25 because the dust is torn off by the blades and the characteristic evaluation test can be executed satisfactorily. Even when the characteristic evaluation test is continued further, the problems in the prior art is resolved that the adhered dust is remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, the necessity of cleaning is reduced remarkably, and a great deal of time for cleaning is not required.
- the ends of the contact members 44 on the side of the IC 22 has blades 32 having a linear ridge to make the contact length of the external terminals 25 with the blade-shaped contact members 44 long.
- the blades may have such a curved surface as a spherical surface.
- the pressing portions of the contact members 44 are of the convexities 47 to make the stroke length at the contact portions of the upper contact end faces 43 a longer, the deformed structure shown in FIGS. 12 and 13 may be used to make the stroke length shorter, inversely, by changing the compression characteristics between the blade-shaped contact members 44 and the elastic contactors 43 .
- an end of a blade-shaped contact members 144 on the side of the test board 23 has a convexity 147 with a flat end face in contact with an upper contact end faces 43 a of the elastic contactors 43 .
- the flat end faces of the convexity 147 and the flat upper end surface 43 a of the elastic contactors 43 are in contact with each other and the elastic deformation amount of the upper contact end faces 43 a is reduced under a given compression force, and the stroke length can be shortened. Even in the deformed structure, the same effect as that of the second embodiment can be obtained.
- FIGS. 14 and 15 are drawings of the test socket for a semiconductor device showing a third embodiment according to the present invention, wherein FIG. 14 is a top view and FIG. 15 is a cross sectional view showing a part of the test socket.
- the test socket of the present invention as shown in FIG. 14, has a square frame 151 with a concavity space 152 at the center thereof for receiving the IC 22 .
- contact members 153 for the test socket are arranged in a surrounding portion in the concavity space 152 of the frame 151 .
- the contact members 153 are composed of the positioning members 48 , the blade-shaped contact members 44 , the insulating base 42 , and the elastic contactors 43 embedded in the insulating base 42 .
- the positioning members 48 in a similar manner as mentioned above, the positioning holes 49 are provided, which are arranged in a matrix form on the insulating plate.
- the blade-shaped contact members 44 are pressed into the positioning holes 49 .
- the four blades are formed to support the external terminals 25 made of ball-shaped solder fixed to the bottom of the IC 22 at the time of test.
- the positioning holes 49 of the positioning members 48 position the blade-shaped contact members 44 in the transverse direction and press the flanges 35 of the blade-shaped contact members 44 by the bottom surface of the positioning members 48 so as to prevent them from getting out of the holes.
- the thickness of the positioning members 48 is so selected that the four blades of the blade-shaped contact members 44 are in contact with the external terminals 25 at predetermined pressure caused by the deformation of the elastic contactors 43 within the range of the elastic deformation when IC 22 is compressed downward.
- the contact members 44 are put on the respective upper contact end faces 43 a of the elastic contactors 43 berried in the insulating base 42 , in such a manner that the respective convexities 47 come in contact with the respective upper contact end faces 43 a of the elastic contactors 43 .
- the positioning members 48 are then placed over the blade-shaped contact members 44 so that each of blade-shaped contact members 44 may be inserted into each of the positioning holes 49 and that the positioning members 48 are may be put on the flanges 35 .
- the IC 22 is mounted in the test socket 41 so that the external terminals 25 may touch the corresponding blade-shaped contact members 44 in the positioning holes 48 .
- the test socket 41 is put on the test board 23 of the test equipment, and the IC 22 mounted in the test socket 41 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing.
- the upper contact end faces 43 a of the elastic contactors 43 are elastically deformed until the external terminals 25 on the bottom of the package 24 of the IC 22 touch the top of the blade-shaped contact members 44 .
- the lower contact end faces 43 b are thus in contact with the contact pads 26 of the test board 23 with predetermined pressure and the external terminals 25 of the IC 22 and the corresponding contact pads 26 of the test board 23 are made conductive with each other.
- the line length of the test socket 41 becomes, for example, 1 mm or less and the inductance is 0.5 nH or less, which is the same as that of the first embodiment.
- the test board 23 , the insulating base 42 , and the positioning members 48 are laminated properly interposing spacers 154 and finally the frame 151 is laminated on them.
- Positioning pins 155 are inserted from the bottom of the frame 151 passing through the test board 23 , the insulating base 42 , the positioning members 48 and the spacer 154 . With the positioning pins 155 , the external terminals 25 , the positioning members 48 , the insulating base 42 , and the test board 23 of the IC 22 are aligned in their mutual positions.
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- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
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- General Physics & Mathematics (AREA)
- Testing Of Individual Semiconductor Devices (AREA)
- Measuring Leads Or Probes (AREA)
- Connecting Device With Holders (AREA)
Abstract
Description
- The present invention relates to a test socket of a semiconductor device to be used, for example, to connect a semiconductor package having a ball-shaped external terminal projected from the package bottom to test equipment.
- A conventional test socket of a semiconductor device will be explained by referring to FIGS.1 to 3.
- Firstly, the first prior art will be explained referring to FIG. 1. FIG. 1 is a cross sectional view showing a basic constitution of a
contact member 1 of a spring probe pin type test socket. The spring probe pin type test socket is a test socket for executing a characteristic evaluation test of, for example, an FBGA (flat package ball grid array) IC (integrated circuit) 2 in whichmany contact members 1 are installed in the test socket. Each of thesecontact members 1 is structured so as to receive a ball-shapedexternal terminal 3 made of solder projecting from a bottom of a package ofIC 2 with a concavity at an upper end thereof being supported by a pin support member not shown in the drawing. The lower end thereof is in contact with acontact pad 5 of atest board 4 corresponding to theexternal terminal 3 of theIC 2.External terminal 3 andpad 5 are thus connected to be conductible to each other, thereby DC characteristic evaluation or AC characteristic evaluation such as the high frequency characteristics and high-speed characteristics are carried out. - The
contact member 1 has a metalliccylindrical case 6 with an upper end closed, acompression spring 7 housed in thecase 6 for generating compression force in the axial direction, and a contact end 8 projecting downward from a lower end opening of thecase 6. An upper end of the contact end 8 is connected to ametallic plunger 9, which is compressed by thespring 7 in thecylindrical case 6. Furthermore, at the upper end of thecase 6, a concavity 10 is formed. The characteristic evaluation test of theIC 2 is executed under the condition that theexternal terminal 3 on the bottom of theIC 2 is pressed against the upper end concavity 10 of thecontact member 1 installed to the test socket and that the contact end 8 of theplunger 9 projected downward is pressed against thecontact pad 5 of thetest board 4 of the test equipment at the same time. - However, the
contact member 1 of the spring probe pin type test socket has a line length of, for example, 3 to 5 mm and has an inductance of 1 nH to 1.5 nH or so due to the structure in which the upper end concavity 10 and the contact end 8 are respectively pressed against the correspondingexternal terminal 3 andcontact pad 5 so as to conduct to each other by theplunger 9 compressed by thespring 7 housed in thecase 6 and connected. As a result, at the time of evaluation of the characteristics at a frequency of several GHz, the line length must be shorter. However, due to the structure of the spring probe pin type test socket, it is difficult to shorten the line length. Thus, a test socket for high frequency having a short line length and low inductance must be used which means a replacement of the test socket. - Next, the second prior art will be explained referring to FIG. 2. FIG. 2 is a cross sectional view showing a basic structure of a
contact member 11 of a sheet type test socket. In FIG. 2, thecontact member 11 is a test socket for executing the characteristic evaluation test of theIC 2 of the FBGA type described above, which is structured so that manymetallic wires 13 are embedded overall a sheet-likeinsulating base 12 at a fine pitch and are inclined to a surface of the sheet. - At the time of conducting the DC characteristic evaluation or the AC characteristic evaluation such as the high frequency characteristics and high-speed characteristics, the
contact member 11 of the test socket is arranged between theIC 2 and thetest board 4 of the test equipment. Theexternal terminal 3 of theIC 2 and thecorresponding contact pad 5 of thetest board 4 are arranged facing to each other across thecontact member 11. Thereafter, theexternal terminal 3 and thecontact pad 5 are pressed against thecontact member 11. With the arrangement, a part of thewires 13 obliquely embedded in theinsulating base 12 and in contact with theexternal terminal 3 are also in contact with thecontact pad 5 and thereby being made conductive to each other. - In the
contact member 11 of the test socket having the structure described, the length of the obliquemetallic wires 13, that is, the line length is about 1.1 mm when the thickness of theinsulating base 12 is about 1 mm, for example, which is shorter than that of the first prior art and the inductance is 0.2 nH or less, which is also lower than that of the first prior art. As a result, characteristics at a frequency of several GHz can be evaluated. - However, in the test socket of the second prior art, solder dust or package dust adhered on the surface of the
external terminal 3 is also adhered on the surface of thecontact member 11 in contact with theexternal terminal 3 of theIC 2 when theIC 2 characteristic evaluation test is executed many times. When the characteristic evaluation test is continued further, the adhered dust remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, whenever the contact count reaches about 1500 times, for example, thecontact member 11 must be frequently cleaned for which a great deal of time is required. - In the test socket, on the other hand, the cost is very high due to the structure of the
contact member 11 in which themetallic wires 13 are arranged regularly overall theinsulating base 12. - Next, the third prior art will be explained referring to FIG. 3. FIG. 3 is a cross sectional view showing the basic structure of a
contact member 14 of a sheet type test socket for executing the characteristic evaluation test of theIC 2 of FBGA described above. Thecontact member 14 holds many conductiveelastic contactors 16 at a position corresponding to theexternal terminal 3 on the bottom of the package ofIC 2 of the sheet-like insulating base 15. Each of theelastic contactors 16 is formed passing through theinsulating base 15 and having anupper contact part 16 a and alower contact part 16 b respectively projected from an upper and a lower surface of theinsulating base 15. - At the time of conducting the DC characteristic evaluation and the AC characteristic evaluation such as the high frequency characteristics and high speed characteristics, the
contact member 14 of the test socket is arranged between theIC 2, so that thetest board 4 of the test equipment and the contact surface of thelower contact part 16 b of theelastic contactor 16 is positioned right above thecontact pad 5 of thetest board 4. Further, the corresponding theexternal terminal 3 of theIC 2 is positioned right above the contact surface of theupper contact part 16 a of theelastic contactor 16. Thereafter, theexternal terminal 3 is pressed against the contact surface of theupper contact part 16 a of theelastic contactor 16 installed on thecontact member 14 and the contact surface of thelower contact part 16 b of theelastic contactors 16 is pressed against the top of thecontact pad 5 of thetest board 4. With the arrangement, theexternal terminal 3 and thecontact pad 5 are made conductive to each other via theelastic contactor 16. - When the total height of the
elastic contactor 16 held by theinsulating base 15, that is, the line length is selected as about 0.7 mm, for example, in thecontact member 14 of the test socket having the structure described, it is shorter than that of the second prior art having such a low inductance as 1.0 nH. As a result, characteristics at a higher frequency than that of the second prior art can be evaluated. - However, in the test socket described, as well as in the second prior art, solder dust or package dust adhered on the surface of the
external terminal 3 is also adhered on the surface of theelastic contactor 16 of thecontact member 14 in contact with theexternal terminal 3 of the IC when theIC 2 characteristic evaluation test is executed many times. When the characteristic evaluation test is continued further, the adhered dust remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, whenever the contact count reaches about 1500 times, for example, thecontact member 14 must be frequently cleaned for which a great deal of time is required. - The present invention was made under the circumstance described above and has an object to provide a test socket for a semiconductor device which enables the high frequency characteristics evaluation satisfactorily, requires shorter time for cleaning and is easy to handle.
- The test socket for a semiconductor device according to the present invention having contact members which lie between ball-shaped external terminals projected from a surface of the semiconductor device and contact pads of the semiconductor test circuit to make them conductive to each other wherein each of said contact member comprises blade-shaped contact members in contact with one of said external terminals, a positioning member for positioning said blade-shaped contact members having positioning holes into which said blade-shaped contact members are inserted, and a conductive elastic contactor having a top portion which is in contact with said blade-shaped contact member positioned by said positioning member and a bottom portion of which is in contact with one of said contact pads.
- Further, in the test socket for a semiconductor device according to the present invention, the blade-shaped contact members have a plurality of blades arranged so that their outer surfaces form a circular surface and that ridgelines of the blades become gradually low from the outer peripheral surfaces of the circular arrangement toward the center thereof and intersect each other at a bottom part.
- Furthermore, in the test socket of a semiconductor device according to the present invention, the blade-shaped contact member has a flange formed at its bottom which engages a lower surface of the positioning member and prevents the blade-shaped contact member from being get out of the positioning holes upward, when they are inserted into the positioning holes of the positioning members.
- Furthermore, in the test socket for a semiconductor device of the present invention, the blade-shaped contact member has a substantially flat bottom surface, which is in contact with a top of the elastic contactors.
- Furthermore, in the test socket for a semiconductor device according to the present invention, the blade-shaped contact members are installed so as to be removable from the elastic contactors.
- Furthermore, in the test socket for a semiconductor device according to the present invention, the elastic contactors are made of a conductive resin and are embedded in an insulating base at a predetermined pitch.
- Furthermore, in the test socket for a semiconductor device according to the present invention, the insulating base supports the elastic contactors so that both ends thereof are projected from upper and lower surfaces of the insulating base.
- Furthermore, in the test socket for a semiconductor device according to the present invention, either one of the bottom of the blade-shaped contact member and the top of the elastic contactor has either one of a convexity and concavity so that they are fit into each other.
- Furthermore, in the test socket for a semiconductor device according to the present invention, the positioning members having the positioning openings position the contact members and elastic contactors for the external terminals and contact pads.
- Further, the test socket for a semiconductor device according to the present invention having contact members which lie between a plurality of ball-shaped external terminals projected from a surface of the semiconductor device and contact pads of the semiconductor test circuit to make them conductive to each other wherein each of said contact member comprises blade-shaped contact members in contact with one of said external terminals, a positioning member for holding the blade-shaped contact members, and a plurality of conductive elastic contactors having a top portion which is in contact with one of said blade-shaped contact members positioned by said positioning member and a bottom portion of which is in contact with one of said contact pads.
- Further, in the test socket for a semiconductor device according to the present invention, the blade-shaped contact members have a plurality of blades arranged so that their outer surfaces form a circular surface and that ridgelines of the blades become gradually low from the outer peripheral surfaces of the circular arrangement toward the center thereof and intersect each other at a bottom part.
- Furthermore, in the test socket for a semiconductor device according to the present invention, a plurality of positioning holes are formed in the positioning members and the blade-shaped contact member has a flange formed at its bottom which engages a lower surface of the positioning member and prevents the blade-shaped contact member from being get out of the positioning holes upward, when they are inserted into the positioning holes of the positioning members.
- Furthermore, in the test socket of the semiconductor device of the present invention, the blade-shaped contact member has a substantially flat bottom surface, which is in contact with a top of the elastic contactors.
- Furthermore, in the test socket for a semiconductor device according to the present invention, the elastic contactors are made of a conductive resin and are embedded in an insulating base at a predetermined pitch.
- The test socket for a semiconductor device according to the present invention comprises a frame plate having a space for housing the semiconductor device at a center portion thereof, a positioning member in contact with a bottom surface of the frame plate which is arranged so that a part of an upper surface thereof is exposed in the space for housing the semiconductor device, a plurality of blade-shaped contact members fixedly received in a plurality of positioning holes formed in the positioning member, an insulating base arranged so as to be in contact with a bottom surface of the positioning member, a plurality of elastic contactors embedded in an insulating base at a predetermined pitch, and a board arranged in contact with a bottom surface of the insulating base on which the semiconductor test circuit is formed.
- Furthermore, in the test socket for a semiconductor device according to the present invention, positioning pins are fixed to the frame plate penetrating through the positioning member, insulating base, and the board on which the semiconductor test circuit are formed.
- FIG. 1 is a cross sectional view showing the basic structure of a conventional test socket for a semiconductor device.
- FIG. 2 is a cross sectional view showing the basic structure of a conventional test socket for a semiconductor device.
- FIG. 3 is a cross sectional view showing the basic structure of a conventional test socket for a conventional semiconductor device.
- FIG. 4 is a cross sectional view showing the basic structure of the test socket for a semiconductor device according to a first embodiment of the present invention.
- FIG. 5 is a partial cross sectional view of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 6 is an enlarged view of the essential section of the test socket for a semiconductor device according to the present invention.
- FIG. 7 is an enlarged view of the essential section of the test socket for a semiconductor device according to the present invention.
- FIG. 8 is a cross sectional view showing a modified example of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 9 is a partial cross sectional view showing a modified example of the test socket for a semiconductor device according to the first embodiment of the present invention.
- FIG. 10 is a cross sectional view showing the basic structure of the test socket for a semiconductor device according to a second embodiment of the present invention.
- FIG. 11 is a cross sectional view showing a part of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 12 is a cross sectional view showing a modified example of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 13 is a partial cross sectional view showing a modified example of the test socket for a semiconductor device according to the second embodiment of the present invention.
- FIG. 14 is a top view of the test socket for a semiconductor device according to a third embodiment of the present invention.
- FIG. 15 is a cross sectional view showing a part of the test socket for a semiconductor device according to the third embodiment of the present invention.
- The embodiments of the present invention will be explained hereunder with reference to the accompanying drawings.
- The first embodiment will be explained by referring to FIGS.4 to 7. FIG. 4 is a cross sectional view showing the basic structure of the test socket of the semiconductor device according to the present invention and FIG. 5 is a cross sectional view showing the essential section thereof. FIGS. 6 and 7 are enlarged views of a part of FIG. 4.
- In FIGS. 4 and 5, a
test socket 21 is a test socket for executing a characteristic evaluation test of an IC (integrated circuit) 22 of a FBGA (flat package ball array). Thetest socket 21 is attached to theIC 22 and then mounted to atest board 23 of the test equipment, thereby the test for characteristic evaluation is executed. On theIC 22 to be tested, a plurality ofexternal terminals 25 made of ball-shaped solder is projected at a predetermined pitch on the bottom of apackage 24. On thetest board 23 of the test equipment, gold-platedcontact pads 26 made of a copper material are mounted corresponding to theexternal terminals 25 of theIC 22 at a predetermined pitch. - On the other hand, the
test socket 21 has acontact member 30 having anelastic contactor 28 mounted on a sheet-like. Anupper contact part 28 a and alower contact part 28 b of theelastic contactor 28 are projected from the top and bottom surfaces of the insulatingbase 27. A metallic blade-shapedcontact member 29 is provided in a removable state so as to cover theupper contact part 28 a of theelastic contactor 28. Thecontact member 30, thus formed, is provided lying between the external terminates 25 of theIC 22 and thecontact pads 26 of thetest boards 23, so that the corresponding external terminals and the contact pads are made conducted to each other. - FIG. 6 is a drawing showing the structure of a blade-shaped
contact member 29, and (A) is a top view, and (B) is a side view. FIG. 7 is also a drawing showing the structure of the blade-shapedcontact member 29, though it is a drawing viewed at a different angle from that shown in FIG. 6. As shown in these drawings, the blade-shapedcontact member 29 has four contact blades 29-1, 29-2, 29-3, and 29-4, each of which forms an arc outer peripheral surface in the top view. The four contact blades 29-1, 29-2, 29-3, and 29-4 are arranged so that the whole outer thereof are almost circular as shown in the top view (A). Inside the circular peripheral surfaces, ridges of the blades 29-1, 29-2, 29-3, and 29-4 descend by a gradual slope from the circular outer peripheral surface toward a center portion thereof and intersect each other at the center portion. The blade-shapedcontact member 29 is made of, for example, beryllium copper having a gold-plated surface. An upper end of thecontact member 29 is in contact with the surface of the ball-shapedexternal terminals 25 of theIC 22 via the ridges of the contact blades 29-1, 29-2, 29-3, and 29-4, and thus one of thecontact members 29 and the correspondingexternal terminal 25 are made conductive to each other. The blade-shapedcontact members 29 were explained as each having four contact blades 29-1, 29-2, 29-3, and 29-4. However, the number of contact blades is not limited to 4 and may be any number more than one. - The insulating
base 27 included in thecontact member 30, as shown in FIGS. 4 and 5, is made of, for example, a polyimide resin film, which allows little deformation in size and has a high heat resistance. In the insulatingbase 27, mountingholes 31 for mounting theelastic contactors 28 are formed at positions corresponding to the locations of theexternal terminals 25 of theIC 22. - Furthermore, the
elastic contactor 28 is made of, for example, synthetic rubber such as conductive silicone rubber, natural rubber, or flexible synthetic resin with carbon, metallic powder, or metal filler mixed. Anupper contact part 28 a and alower contact part 28 b having a shape of truncated cone the diameter of which is larger than that of a mountinghole 31 are formed on both end sides of theelastic contactor 28. Anintermediate part 28 c of theelastic contactor 28 is inserted in the mountinghole 31, thereby fixing theelastic contactor 28 to the insulatingbase 27. - On the other hand, a
concavity 33 with a larger diameter than that of theupper contact part 28 a of theelastic contactor 28 is formed at the end of the blade-shapedcontact member 29 on the side of thetest board 23. Aconic concavity 34 is further formed in theconcavity 33. Aflange 35 is provided extending outward at the end of the blade-shapedcontact member 29 on the side of thetest board 23. When thecontact member 29 covers theupper contact part 28 a of theelastic contactor 28, the conic surface of theconcavity 34 of in theconcavity 33 is in contact with the edge of theupper contact part 28 a. When thecontact member 29 is pressed at the time of the test, theupper contact part 28 a begins to deform thereby making thecontact member 29 and theelastic contactor 28 in conductive to each other. - The
test socket 21 has anupper positioning member 36 and alower positioning member 37 with a predetermined thickness and predetermined hardness for supporting and positioning thecontact member 30 at the time of test. Theupper positioning member 36 and thelower positioning member 37 are made of such an insulating material as a synthetic resin including epoxy resin filled with glass filler, PAT (polyamide-imide), or PES (polyether sulfide), for example. - The
upper positioning member 36 is placed on the insulatingbase 27 to position thecontact member 29 as well as to support theIC 22 at the time of test. Theupper positioning member 36 has a plurality of upper positioning holes 39 in which the blade-shapedcontact members 29 are inserted. Astep portion 38 is formed on the lower sidewall of the upper positioning holes 39 to form a lower part with a large diameter. Theupper positioning hole 39 positions thecontact member 29 in the transverse direction and engages theflange 35 of the blade-shapedcontact member 29 with thestep portion 38 so as to prevent it from getting out of theupper positioning hole 39. - The thickness of the
upper positioning member 36 is appropriately selected within a range of elastic deformation of theupper contact part 28 a of theelastic contactor 28, so that even when theupper contact part 28 a is deformed until theexternal terminal 25 is brought in contact with the four blades of the blade-shapedcontact member 29 by pressing theIC 22 downward, and the bottom of thepackage 24 of theIC 22 touches the top of theupper positioning member 36, a pressure for making a contact between theexternal terminal 25 and the four blades of the blade-shapedcontact member 29 is set to a required value. - On the other hand, the
lower positioning contactor 37 positions theelastic contactor 28 placed on thecontact pad 26 of thetest board 23 as well as supports the insulatingbase 27, theupper positioning member 36 and theIC 22, which are placed on it at the time of test. Lower positioning holes 40 are formed in thelower positioning contactor 37 in which thelower contact parts 28 b of theelastic contactor 28 are inserted. The lower positioning holes 40 position thelower contact parts 28 b of theelastic contactor 28 in the transverse direction, thereby controlling the position of the insulatingbase 27 to which theelastic contactor 28 is mounted in the transverse direction. The thickness of thelower positioning member 37 is appropriately selected within the range of the elastic deformation of thelower contact part 28 b of theelastic contactor 28, thereby making the pressing force between theelastic contactor 28 and thecontact pad 26 is set to a required value. - At the time of the characteristic evaluation test of the
IC 22 with the test socket thus formed, thecontact member 30 in which theupper contact parts 28 a of theelastic contactor 28 mounted on the insulatingbase 27 are covered respectively by thecontact members 29 is combined with thelower positioning members 37 by inserting thelower contact parts 28 b into the corresponding lower positioning holes 40. Thecontact members 29 are then inserted into the corresponding upper positioning holes 39, and theupper positioning members 36 are located on the insulatingbase 27 so that thestep portion 38 is put on theflange 35, thereby constructing thetest socket 21. - The
IC 22 is set in thetest socket 21 so that theexternal terminals 25 are in contact with theconcavities 32 of thecontact members 29 in the corresponding upper positioning holes 39. Then, thetest socket 21 is put on thetest board 2 of the test equipment, and theIC 22 set in thetest socket 21 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing. Theupper contact parts 28 a are deformed until the bottom of thepackage 24 of theIC 22 touches the top of theupper positioning members 36. Thelower contact parts 28 b is elastically deformed until the insulatingbase 27 touches the top of thelower positioning members 37 and the height of thelower contact parts 28 b of theelastic contactors 28 reaches the thickness of thelower positioning members 37. - The bottom of the
lower contact parts 28 b is thus in contact with thecontact pads 26 of thetest board 23 with predetermined compression force and theexternal terminals 25 of theIC 22 are made conductive to thecorresponding contact pads 26 of thetest board 23. With the structure described above, the line length of thetest socket 21 becomes, for example, 1 mm or less and the inductance becomes 0.5 nH or less. - According to the present embodiment explained above, the line length of the
test socket 21 can be shortened and the inductance can be lowered to less than 0.5 nH, so that the characteristics at a high frequency of several GHz can be evaluated. The blade-shapedcontact members 29 are pressed to the ball-shapedexternal terminals 25 of theIC 22 with a long contact length of blades of the blade-shapedcontact members 29 with little contact resistance. - Furthermore, the
contact members 29 are in contact with theexternal terminals 25 via a metallic blades, so that thecontact members 29 are hardly affected by, for example, solder dust or package dust attached to the surface of theexternal terminals 25 and the characteristic evaluation test can be executed in a comparatively satisfactory state. Even when the characteristic evaluation test is continued further, the problems in the prior art is resolved that the adhered dust is remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, the necessity of cleaning is reduced remarkably, and a great deal of time for cleaning is not required. - In the embodiment described above, the ends of the
contact members 29 on the side of theIC 22 are of the blade-shaped shape so as to make the contact length of theexternal terminals 25 with thecontact members 29 longer. However, a pin shape may be applied so as to scratch the surface of theexternal terminals 25 and to realize a sure contact. - Furthermore, the shape of the compressing structure between the
contact members 29 and theelastic contactors 28 may be modified. In the embodiment described, the inner bottoms of the concavities of thecontact members 29 areconic concavities 34 to make the stroke length at the contact portions of theupper contact parts 28 a longer. However, the inner bottoms of the concavities of thecontact members 29 may be concavities having a curved surface such a spherical surface and furthermore, they may be conic projections or projections having a curved surface such a spherical surface. - Inversely, to make the stroke length at the contact portions of the
contact members 29 and theupper contact parts 28 a of theelastic contactors 28 shorter, the concavities may be deformed as shown in FIGS. 8 and 9. Namely, the inner bottoms ofconcavities 133 ofcontact members 129 are a flat surface. The flat upper end surfaces of theupper contact parts 28 a of theelastic contactors 28 are in contact with the inner bottoms of theconcavities 133, and the elastic deformation amount of theupper contact parts 28 a is reduced under the same compression force, and thus the stroke length can be shortened. Even in the deformed structure thus formed, the same effect as that of the first embodiment can be obtained. - Next, the second embodiment of the present invention will be described referring to FIGS.10 to 13. FIG. 10 is a cross sectional view showing a basic structure of the test socket for a semiconductor device according to the present invention and FIG. 11 is a cross sectional view of an partial section thereof. FIG. 12 shows a structure shown in FIGS. 10 and 11, which is slightly deformed. The same numeral is assigned to each of the same parts as those in the first embodiment, and the explanation thereof is omitted. The parts of the embodiment different from those of the first embodiment will be explained bellow.
- In FIGS.10 to 13, a test socket 41 is used to mount the
IC 22 on thetest board 23 and evaluate the characteristics thereof. In the test socket 41,elastic contactors 43 are berried in an elastic laminar insulatingbase 42 so that upper contact end faces 43 a and lower contact end faces 43 b are exposed on the top and bottom surfaces of the elastic laminar insulatingbase 42. In the test socket 41, metallic blade-shapedcontact members 44 in contact with the upper contact end faces 43 a of theelastic contactors 43 are mounted in a removable state and theelastic contactors 43 and the blade-shapedcontact members 44 constitute acontact member 45. Thecontact member 45 lies between theexternal terminals 25 of theIC 22 and thecontact pads 26 of thetest board 23, thereby making them in conductive to each other. - Further, the insulating
base 42 and theelastic contactors 43 of thecontact member 45 are of pillar-like shape and are made of, for example, synthetic rubber such as silicone rubber, or natural rubber, or flexible synthetic resin, which are made conductive by being mixed with, for example, carbon, metallic powder, or metal filler. Theelastic contactors 43 are fit intoholes 46 formed in the corresponding portions to theexternal terminals 25 of theIC 22 of the insulatingbase 42 and integrated with the insulatingbase 42 and theelastic contactors 43 and the insulatingbase 42 form a so-called zebra connector. - The blade-shaped
contact members 44 are made of, for example, beryllium copper having a gold-plated surface and have a structure shown in FIGS. 6 and 7. The ends of the blade-shapedcontact members 44 on the side of theIC 22 are, as described above, in contact with the ball-shapedexternal terminals 25 at the four blade-shaped ridges and are made conductive with the ball-shapedexternal terminals 25. - On the other hand, convexities47 are formed on the end of the blade-shaped
contact members 44 on the side of thetest board 23, which has such a curved surface as an almost spherical surface in contact with the upper contact end faces 43 a of theelastic contactors 43. Furthermore, at the intermediate portion of the blade-shapedcontact members 44, theflanges 35 project outward. When the blade-shapedcontact members 44 come in contact with the upper contact end faces 43 a of theelastic contactors 43 with being compressed to each other, theelastic contactors 43 begin deforming at the portions where theconvexities 47 of the blade-shapedcontact members 44 come in contact, thereby being made conductive with each other. - The test socket41 has
positioning members 48 with a predetermined thickness and hardness for supporting and positioning thecontact member 45 at the time of test. Thepositioning members 48 are made of such an insulating material as a synthetic resin including epoxy resin filled with glass filler, PAI (polyamide-imide), or PES (polyether sulfide), for example. - The positioning
member 48 is placed on the insulatingbase 42 for supporting theIC 22 and has positioning holes 49 for positioning the blade-shapedcontact members 44 by being inserted in the positioning holes 49 at the time of test. The positioning holes 49 position the blade-shapedcontact members 44 in the transverse direction and press theflanges 35 of the blade-shapedcontact members 44 at the bottom of thepositioning members 48 so as to prevent them from getting out of the positioning holes 49. The thickness of thepositioning members 48 is so selected that the four blades of the blade-shapedcontact members 44 are in contact with theexternal terminals 25 at predetermined pressure caused by the deformation of theelastic contactors 43 within the range of the elastic deformation whenIC 22 is compressed downward. - At the time of the characteristic evaluation test of the
IC 22 by the test socket thus constructed, thecontact members 44 are put on the respective upper contact end faces 43 a of theelastic contactors 43 berried in the insulatingbase 42, in such a manner that therespective convexities 47 come in contact with the respective upper contact end faces 43 a of theelastic contactors 43. Thepositioning members 48 are then placed over the blade-shapedcontact members 44 so that each of blade-shapedcontact members 44 may be inserted into each of the positioning holes 49 and that thepositioning members 48 are may be put on theflanges 35. - Then, the
IC 22 is mounted in the test socket 41 so that theexternal terminals 25 may touch the corresponding blade-shapedcontact members 44 in the positioning holes 48. Then, the test socket 41 is put on thetest board 23 of the test equipment, and theIC 22 mounted in the test socket 41 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing. The upper contact end faces 43 a of theelastic contactors 43 are elastically deformed until theexternal terminals 25 on the bottom of thepackage 24 of theIC 22 touch the top of the blade-shapedcontact members 44. - The lower contact end faces43 b are thus in contact with the
contact pads 26 of thetest board 23 with predetermined pressure and theexternal terminals 25 of theIC 22 and thecorresponding contact pads 26 of thetest board 23 are made conductive with each other. With the structure described, the line length of the test socket 41 becomes, for example, 1 mm or less and the inductance is 0.5 nH or less, which is the same as that of the first embodiment. - According to the present embodiment explained above, as is the case with the first embodiment, the line length of the
test socket 21 can be shortened and the inductance can be lowered to less than 0.5 nH, so that the characteristics at a high frequency of several GHz can be evaluated. The blade-shapedcontact members 29 are pressed to the ball-shapedexternal terminals 25 of theIC 22 with a long contact length of blades of the blade-shapedcontact members 29 with little contact resistance. - Furthermore, with the blade-shaped
contact members 44 being in contact with theexternal terminals 25 of through metallic blades, thecontact members 29 are hardly affected by, for example, solder dust or package dust adhered to the surface of theexternal terminals 25 because the dust is torn off by the blades and the characteristic evaluation test can be executed satisfactorily. Even when the characteristic evaluation test is continued further, the problems in the prior art is resolved that the adhered dust is remained and piled increases contamination, which impedes a result of the characteristic evaluation test. Therefore, the necessity of cleaning is reduced remarkably, and a great deal of time for cleaning is not required. - In the second embodiment, the ends of the
contact members 44 on the side of theIC 22 hasblades 32 having a linear ridge to make the contact length of theexternal terminals 25 with the blade-shapedcontact members 44 long. However, the blades may have such a curved surface as a spherical surface. Further, although the pressing portions of thecontact members 44 are of theconvexities 47 to make the stroke length at the contact portions of the upper contact end faces 43 a longer, the deformed structure shown in FIGS. 12 and 13 may be used to make the stroke length shorter, inversely, by changing the compression characteristics between the blade-shapedcontact members 44 and theelastic contactors 43. - Namely, in
contact members 145 of atest socket 141, an end of a blade-shapedcontact members 144 on the side of thetest board 23 has aconvexity 147 with a flat end face in contact with an upper contact end faces 43 a of theelastic contactors 43. The flat end faces of theconvexity 147 and the flat upper end surface 43 a of theelastic contactors 43 are in contact with each other and the elastic deformation amount of the upper contact end faces 43 a is reduced under a given compression force, and the stroke length can be shortened. Even in the deformed structure, the same effect as that of the second embodiment can be obtained. - FIGS. 14 and 15 are drawings of the test socket for a semiconductor device showing a third embodiment according to the present invention, wherein FIG. 14 is a top view and FIG. 15 is a cross sectional view showing a part of the test socket. In these drawings, the same numeral is assigned to each of the parts shown in FIGS.4 to 15 and detailed explanation will be omitted. The test socket of the present invention, as shown in FIG. 14, has a
square frame 151 with aconcavity space 152 at the center thereof for receiving theIC 22. In a surrounding portion in theconcavity space 152 of theframe 151,contact members 153 for the test socket are arranged. - The
contact members 153 are composed of thepositioning members 48, the blade-shapedcontact members 44, the insulatingbase 42, and theelastic contactors 43 embedded in the insulatingbase 42. In thepositioning members 48, in a similar manner as mentioned above, the positioning holes 49 are provided, which are arranged in a matrix form on the insulating plate. The blade-shapedcontact members 44 are pressed into the positioning holes 49. At the upper ends of the blade-shapedcontact members 44, in a similar manner as described above, the four blades are formed to support theexternal terminals 25 made of ball-shaped solder fixed to the bottom of theIC 22 at the time of test. The positioning holes 49 of thepositioning members 48 position the blade-shapedcontact members 44 in the transverse direction and press theflanges 35 of the blade-shapedcontact members 44 by the bottom surface of thepositioning members 48 so as to prevent them from getting out of the holes. The thickness of thepositioning members 48 is so selected that the four blades of the blade-shapedcontact members 44 are in contact with theexternal terminals 25 at predetermined pressure caused by the deformation of theelastic contactors 43 within the range of the elastic deformation whenIC 22 is compressed downward. - At the time of the characteristic evaluation test of the
IC 22 by the test socket thus constructed, thecontact members 44 are put on the respective upper contact end faces 43 a of theelastic contactors 43 berried in the insulatingbase 42, in such a manner that therespective convexities 47 come in contact with the respective upper contact end faces 43 a of theelastic contactors 43. Thepositioning members 48 are then placed over the blade-shapedcontact members 44 so that each of blade-shapedcontact members 44 may be inserted into each of the positioning holes 49 and that thepositioning members 48 are may be put on theflanges 35. - Then, the
IC 22 is mounted in the test socket 41 so that theexternal terminals 25 may touch the corresponding blade-shapedcontact members 44 in the positioning holes 48. Then, the test socket 41 is put on thetest board 23 of the test equipment, and theIC 22 mounted in the test socket 41 is compressed by a compression mechanism of the test equipment, which is not shown in the drawing. The upper contact end faces 43 a of theelastic contactors 43 are elastically deformed until theexternal terminals 25 on the bottom of thepackage 24 of theIC 22 touch the top of the blade-shapedcontact members 44. - The lower contact end faces43 b are thus in contact with the
contact pads 26 of thetest board 23 with predetermined pressure and theexternal terminals 25 of theIC 22 and thecorresponding contact pads 26 of thetest board 23 are made conductive with each other. With the structure described, the line length of the test socket 41 becomes, for example, 1 mm or less and the inductance is 0.5 nH or less, which is the same as that of the first embodiment. - As shown in FIG. 15, the
test board 23, the insulatingbase 42, and thepositioning members 48 are laminated properly interposingspacers 154 and finally theframe 151 is laminated on them. Positioning pins 155 are inserted from the bottom of theframe 151 passing through thetest board 23, the insulatingbase 42, thepositioning members 48 and thespacer 154. With the positioning pins 155, theexternal terminals 25, thepositioning members 48, the insulatingbase 42, and thetest board 23 of theIC 22 are aligned in their mutual positions. - It is well understood from the description above that, according to the present invention, high frequency characteristics can be satisfactorily evaluated, even when the characteristic evaluation test is repeatedly executed, since the test socket is hardly contaminated. It is also understood that the cleaning of the test socket does not require a great deal of time, which means that the maintenance and handling of the test socket is easy.
Claims (16)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000124208A JP2001307851A (en) | 2000-04-25 | 2000-04-25 | Test socket of semiconductor device |
JP2000-124208 | 2000-04-25 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20010050427A1 true US20010050427A1 (en) | 2001-12-13 |
US6426553B2 US6426553B2 (en) | 2002-07-30 |
Family
ID=18634377
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/839,239 Expired - Fee Related US6426553B2 (en) | 2000-04-25 | 2001-04-23 | Test socket of semiconductor device |
Country Status (2)
Country | Link |
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US (1) | US6426553B2 (en) |
JP (1) | JP2001307851A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150181708A1 (en) * | 2013-12-20 | 2015-06-25 | Samsung Electro-Mechanics Co., Ltd. | Semiconductor package module |
CN108780117A (en) * | 2016-03-23 | 2018-11-09 | 李诺工业股份有限公司 | Test jack component |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20030067401A (en) * | 2002-02-08 | 2003-08-14 | 정운영 | Test socket |
JP2003272788A (en) * | 2002-03-19 | 2003-09-26 | Enplas Corp | Socket for electric parts |
TWI280693B (en) * | 2004-09-10 | 2007-05-01 | Hon Hai Prec Ind Co Ltd | Electrical connector |
KR100929645B1 (en) * | 2008-03-31 | 2009-12-03 | 리노공업주식회사 | Socket for semiconductor chip inspection |
CN102422726B (en) | 2009-03-10 | 2015-07-01 | 约翰国际有限公司 | Electrically conductive pins for microcircuit tester |
US20130002285A1 (en) | 2010-03-10 | 2013-01-03 | Johnstech International Corporation | Electrically Conductive Pins For Microcircuit Tester |
JP5436122B2 (en) * | 2009-09-28 | 2014-03-05 | 株式会社エンプラス | Socket for electrical parts |
US9007082B2 (en) | 2010-09-07 | 2015-04-14 | Johnstech International Corporation | Electrically conductive pins for microcircuit tester |
TWI534432B (en) | 2010-09-07 | 2016-05-21 | 瓊斯科技國際公司 | Electrically conductive pins for microcircuit tester |
TWM439923U (en) * | 2012-04-09 | 2012-10-21 | Hon Hai Prec Ind Co Ltd | Electrical connector |
KR101749711B1 (en) * | 2015-11-30 | 2017-06-21 | 주식회사 대성엔지니어링 | Test socket |
KR101920855B1 (en) * | 2017-05-11 | 2018-11-21 | 주식회사 아이에스시 | Electrical test socket |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2739031B2 (en) * | 1992-12-08 | 1998-04-08 | 三菱電機株式会社 | Socket for semiconductor device |
US5493237A (en) | 1994-05-27 | 1996-02-20 | The Whitaker Corporation | Integrated circuit chip testing apparatus |
US6120885A (en) * | 1997-07-10 | 2000-09-19 | International Business Machines Corporation | Structure, materials, and methods for socketable ball grid |
US6283780B1 (en) * | 1998-04-01 | 2001-09-04 | Molex Incorporated | Test socket lattice |
US6313999B1 (en) * | 1999-06-10 | 2001-11-06 | Agere Systems Optoelectronics Guardian Corp. | Self alignment device for ball grid array devices |
-
2000
- 2000-04-25 JP JP2000124208A patent/JP2001307851A/en not_active Abandoned
-
2001
- 2001-04-23 US US09/839,239 patent/US6426553B2/en not_active Expired - Fee Related
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150181708A1 (en) * | 2013-12-20 | 2015-06-25 | Samsung Electro-Mechanics Co., Ltd. | Semiconductor package module |
CN108780117A (en) * | 2016-03-23 | 2018-11-09 | 李诺工业股份有限公司 | Test jack component |
Also Published As
Publication number | Publication date |
---|---|
JP2001307851A (en) | 2001-11-02 |
US6426553B2 (en) | 2002-07-30 |
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