Probe unit, probe head, probe card and probe system

Abstract

A probe unit includes a first probe and a second probe of the same length. Each probe body has at least one through-hole extending along its longitudinal direction, creating a hollow shape. The slit defines at least two plates, with the total cross-sectional area of ​​the plates of the first probe being larger than that of the plates of the second probe. Alternatively, the second probe body may be solid without slits, and the total cross-sectional area of ​​the plates of the first probe may be larger than that of the second probe body. The shape of the plates is selected such that the contact force of the first probe is greater than that of the second probe, thereby meeting the testing requirements of probe contact areas of different sizes on electronic devices under test, while simultaneously avoiding problems such as different tip wear rates and excessively large differences in the area ratio of probe marks.

Description

[Technical Field]

[0001] This invention relates to probes in probe cards, and more particularly to a probe unit comprising probes of different shapes, and a probe head, probe card and probe system employing said probe unit. [Previous Technology]

[0002] When testing devices on a conventional wafer, a probe card is typically used to transmit signals between a device under test (DUT) and a testing machine. The probe card is equipped with multiple probes to contact multiple probe contact areas of the DUT, such as pads or bumps. Some DUT probe contact areas have different current requirements and different sizes. Generally, high current corresponds to large probe contact areas, and these large contact areas are spaced further apart. Conversely, low current typically corresponds to small probe contact areas, and these small contact areas are spaced further apart. Therefore, if the probe card is equipped with only thin probes, there will be insufficient contact force and current carrying capacity for probes with high current requirements and large contact areas. Conversely, if the probe cards are all equipped with coarse probes, there will be excessive probe pressure, which may damage the probe contact area, which has a small current requirement and a corresponding small size.

[0003] Please refer to Taiwan Patent No. I695549, which proposes a scheme that uses probes with different cross-sectional areas simultaneously, that is, using both coarse and fine probes. While this can solve the above-mentioned problem, the probes have the same bending stiffness, thus generating the same contact force. In other words, the probes contact different sized probe contact areas on the tested device with the same contact force, which will result in inconsistent tip wear rates and / or excessively large differences in the area ratio of the needle marks.

[0004] In detail, the tip wear rate depends on the contact force per unit area. When a coarse probe and a fine probe contact the large and small probe contact areas with the same contact force, respectively, the tip wear rate of the fine probe will be higher than that of the coarse probe. The needle mark area ratio refers to the ratio of the area of ​​the mark produced by the probe flattening the top of the bump to the cross-sectional area of ​​the bottom of the bump when the probe contact area of ​​the device under test is a bump. When a coarse probe and a fine probe contact the large and small bumps with the same contact force, respectively, the needle mark area ratio produced by the fine probe will be greater than that produced by the coarse probe, resulting in an inconsistency in the height of the large and small bumps after the test. [Summary of the Invention]

[0005] This invention discloses a probe unit, probe head, probe card and probe system, which uses probes with different cross-sectional areas and can suppress the adverse effects caused by the difference in the wear rate of the probe tip, and can also control the difference in the area ratio of the probe marks within an acceptable range.

[0006] This invention discloses a probe unit for contacting a plurality of probe contact blocks of an electronic test device integrated on a semiconductor wafer. The probe unit includes a plurality of probes of the same length, each probe including a tail and a tip at its two ends, and a body between the tail and the tip. The body includes at least one slit extending along its longitudinal direction. The slit penetrates the body along a first transverse axis, making the body hollow and defining at least two pieces by the at least one slit. The at least two pieces are separated from each other along a second transverse axis and can be elastically bent under a load. Each piece can define a cross-sectional area on an imaginary plane parallel to the first and second transverse axes. The sum of the cross-sectional areas of the at least two pieces of each probe is defined as a total cross-sectional area. The plurality of probes includes a first probe and a second probe. The total cross-sectional area of ​​the sheet of the first probe is greater than the total cross-sectional area of ​​the sheet of the second probe. The shapes of the sheet of the first probe and the sheet of the second probe are different from each other. The shapes of the sheet of the first and second probes are selected such that the contact force of the first probe is greater than the contact force of the second probe.

[0007] Accordingly, the present invention employs a hybrid probe approach, that is, simultaneously using at least two probe types, namely a first probe and a second probe. The width and thickness of the first and second probes can be designed to match the size and spacing of the probe contact areas of the electronic device under test that they need to contact. Furthermore, the rigidity of the probes can be appropriately reduced through the design of the slits in the probe body (design width, number, etc.), thereby appropriately reducing the contact force of the probes. This allows the first and second probes to meet the testing requirements of their corresponding probe contact areas in various aspects. Specifically, the first probe has a larger total cross-sectional area, which can meet the high current requirements of larger probe contact areas, while the larger probe contact areas can withstand the larger contact force of the first probe without easily being damaged. The second probe has a smaller total cross-sectional area, which can meet the low current requirements of smaller probe contact areas, while the smaller contact force of the second probe can avoid damaging the smaller probe contact areas. More importantly, the first and second probes can contact larger and smaller probe contact areas with larger and smaller contact forces, respectively. Therefore, the ratio of contact force to contact area of ​​the first and second probes can be made consistent or similar through size design, resulting in consistent or similar tip wear rates for the first and second probes, and consequently, consistent or similar lengths for the first and second probes. Furthermore, the size design can produce consistent or similar probe mark area ratios for the large and small bumps of the electronic device under test that the first and second probes contact, resulting in consistent or similar heights for the large and small bumps after testing.

[0008] Preferably, the ratio of the contact force of the first probe to the contact force of the second probe is greater than 1 and less than 4. This can meet the needs of most wafer testing.

[0009] Preferably, the body of each probe can be defined with a thickness in the first transverse axis and a width in the second transverse axis, and the width of the body of each probe is less than or equal to the thickness.

[0010] In other words, the probe's cross-sectional shape can be square or rectangular, with the longer side of the rectangle pointing in the direction of the probe's thickness, i.e., the first transverse axis. Since the probe's slit extends through the probe body along the first transverse axis, the probe body bends along the second transverse axis (i.e., the axis defining the width) during use. A probe with a square cross-section not only better matches the shape of the probe contact area of ​​the electronic test device, but also, since the width of the probe body is no greater than its thickness, it facilitates the elastic deformation effect when bending along the second transverse axis. A probe with a rectangular cross-section, whose width is less than its thickness, exhibits even better elastic deformation when bending along the second transverse axis. Furthermore, the probe body's width being less than or equal to its thickness allows the probe body to have sufficient thickness to maintain a certain current-carrying capacity.

[0011] Preferably, the tip of the first probe includes a base connected to the needle body and an end connected to the base. The end is used to contact the probe contact area of ​​the electronic device under test. The base and the end can define a cross-sectional area on an imaginary plane parallel to the first transverse axis and the second transverse axis, respectively. The cross-sectional area of ​​the end is smaller than the cross-sectional area of ​​the base.

[0012] In other words, the tip of the first probe has a thinned and / or narrowed end. That is, the base may have the same outer contour size as the needle body, while the end is further reduced in thickness and / or width compared to the base, so that the cross-sectional area of ​​the end is smaller than that of the base. Such a structural design also helps to adjust the tip wear rate of the first probe and the ratio of the resulting needle mark area, thereby making the tip wear rates of the first and second probes consistent or similar, and making the first and second probes produce consistent or similar needle mark area ratios.

[0013] More preferably, the tip of the second probe can define a cross-sectional area on an imaginary plane parallel to the first transverse axis and the second transverse axis, and the cross-sectional area of ​​the end of the tip of the first probe is greater than or equal to the cross-sectional area of ​​the tip of the second probe.

[0014] Accordingly, when the first and second probes contact the probe contact area of ​​the electronic test device, the contact area of ​​the first probe will be greater than or equal to the contact area of ​​the second probe. Such a structural design also helps to make the tip wear rate of the first and second probes consistent or similar, and to make the first and second probes produce consistent or similar needle mark area ratios.

[0015] More preferably, the ratio of the cross-sectional area of ​​the tip of the first probe to the cross-sectional area of ​​the tip of the second probe is greater than 1 and less than 4. This satisfies the requirements of most wafer testing.

[0016] Preferably, the plurality of probe contact blocks of the electronic test device includes a first protrusion and a second protrusion, the maximum cross-sectional area of ​​the first protrusion being greater than the maximum cross-sectional area of ​​the second protrusion; when the tip of the first probe and the tip of the second probe press against the first protrusion and the second protrusion respectively, causing the needle body of the first probe and the needle body of the second probe to bend elastically under load, the first probe forms a first needle mark area on the first protrusion, and the second probe forms a second needle mark area on the second protrusion, and the ratio of the first needle mark area to the maximum cross-sectional area of ​​the first protrusion and the ratio of the second needle mark area to the maximum cross-sectional area of ​​the second protrusion are substantially equal.

[0017] In this way, when the probe contact area of ​​the electronic device under test is a protrusion, the first and second probes produce substantially equal probe mark area ratios for the large protrusion (i.e., the first protrusion) and the small protrusion (i.e., the second protrusion) of the electronic device under test they contact. Substantially equal is defined as a difference of less than or equal to 20%, so that the first and second protrusions have consistent or similar heights after the test.

[0018] Alternatively, the plurality of probe contact blocks of the electronic test device may also include a plurality of first protrusions and a second protrusion, each of the first protrusions and the second protrusion being substantially the same size; the tip of the first probe is used to press against the plurality of first protrusions simultaneously, each of the plurality of first protrusions being configured to transmit a first signal, the first signal being one of a power signal and a ground signal; the tip of the second probe is used to press against the second protrusion, the second protrusion being configured to transmit a second signal, the second signal being a test signal different from the first signal.

[0019] Thus, even if the dimensions of each first protrusion and the second protrusion are substantially the same, the first probe with a larger contact force is used to press against multiple first protrusions at the same time, while the second probe with a smaller contact force is used to press against a single second protrusion. Therefore, the wear rate of the tips of the first and second probes can still be made consistent or similar through the size design, and / or the first protrusion and the second protrusion can produce a consistent or similar needle mark area ratio.

[0020] Preferably, the needle body of each probe can be defined with a thickness in the first transverse axis and a width in the second transverse axis, and the ratio of the width to the thickness of the needle body of the first probe is less than the ratio of the width to the thickness of the needle body of the second probe.

[0021] Accordingly, the ratio of the width to the thickness of the first probe body is smaller, which helps to improve its elastic deformation effect when bending along the second transverse axis, so that the first probe body with a larger total cross-sectional area and the second probe body with a smaller total cross-sectional area can produce the same or similar elastic deformation effect, thereby producing the same or similar needle measurement performance.

[0022] Preferably, the first probe and the second probe are made of different materials with different hardness.

[0023] Accordingly, the first probe and the second probe can be made of materials with different hardness. For example, the second probe with a smaller total cross-sectional area can be made of a harder material to slow down its tip wear rate, which also helps to make the tip wear rates of the first and second probes consistent or similar.

[0024] More preferably, the material hardness of the second probe is greater than that of the first probe.

[0025] In this way, the second probe with a smaller total cross-sectional area is made of a harder material, which can slow down its tip wear rate and help to make the tip wear rates of the first and second probes consistent or similar.

[0026] Preferably, at least one bump group is provided in the slit of the first probe (meaning that at least one bump group may also be provided in the slit of the second probe, or there may be no bump group in the slit of the second probe), the bump group includes two bumps, the two bumps protruding from the two adjacent pieces facing each other.

[0027] In this way, when the probe body is subjected to load and bends elastically, the two protrusions facing each other in the slit will abut against each other, thus preventing adjacent pieces from contacting each other and wearing out, thereby increasing the service life of the probe. Moreover, by having the two protrusions facing each other abut against each other, the pieces can maintain a consistent yaw direction and a certain distance, which is helpful for the electrical performance of high-frequency and high-speed testing.

[0028] The present invention further provides another probe unit for contacting a plurality of probe contact blocks of an electronic test device integrated on a semiconductor wafer. The probe unit includes a plurality of probes of the same length, each probe including a tail and a tip at its two ends, and a body between the tail and the tip. The plurality of probes includes a first probe and a second probe. The body of the first probe includes at least one slit extending along its longitudinal direction. The slit penetrates the body of the first probe along a first transverse axis, such that the body of the first probe is hollow and defined by the at least one slit as at least two pieces. The at least two pieces are separated from each other along a second transverse axis and can be elastically bent under a load. The body of the second probe is solid and can be elastically bent under a load. The tail and tip of each probe, each piece of the first probe, and the body of the second probe can each define a cross-sectional area on an imaginary plane parallel to the first and second transverse axes. The sum of the cross-sectional areas of the at least two pieces of the first probe is defined as a total cross-sectional area. The total cross-sectional area of ​​the pieces of the first probe is greater than the cross-sectional area of ​​the body of the second probe. The cross-sectional area of ​​the body of the second probe is less than the cross-sectional area of ​​the tail of the second probe and less than the cross-sectional area of ​​the tip of the second probe. The shape of the pieces of the first probe is selected such that the contact force of the first probe is greater than the contact force of the second probe.

[0029] Accordingly, the present invention adopts a mixed-probe approach, that is, simultaneously employing at least two probe types, namely a first probe and a second probe. The width and thickness of the first and second probes can be designed to match the size and spacing of the probe contact areas of the electronic device under test to be contacted. Furthermore, the rigidity of the first probe can be appropriately reduced by designing the width of the slit in its body, thereby appropriately reducing the contact force of the probe. Similarly, the rigidity of the second probe can be appropriately reduced by reducing the cross-sectional area of ​​its body relative to the tail and tip, thereby appropriately reducing the contact force of the probe. In other words, although the body of the first probe is hollow and the body of the second probe is solid, the cross-sectional area of ​​both probes can be designed to ensure that the first and second probes meet the testing requirements of their corresponding probe contact areas in various aspects. Specifically, the first probe has a larger total cross-sectional area, which can meet the high current requirements of a larger probe contact area, while the larger probe contact area can withstand the larger contact force of the first probe without easily being damaged. The second probe has a smaller cross-sectional area, which can meet the low current requirements of a smaller probe contact area, while the smaller contact force of the second probe can avoid damaging the smaller probe contact area. More importantly, the first and second probes can contact the larger and smaller probe contact areas with larger and smaller contact forces, respectively. Therefore, the ratio of contact force to contact area of ​​the first and second probes can be made consistent or similar through size design, so that the tip wear rate of the first and second probes is consistent or similar, thereby maintaining consistent or similar lengths of the first and second probes. Furthermore, the size design can produce consistent or similar needle mark area ratios for the large and small bumps of the electronic device under test that the first and second probes contact, so that the large and small bumps have consistent or similar heights after testing.

[0030] Preferably, the needle body of the first probe can be defined with a thickness in the first transverse axis and a width in the second transverse axis, wherein the width of the needle body of the first probe is less than or equal to the thickness.

[0031] In other words, the cross-sectional shape of the first probe can be square or rectangular, and the long side of the rectangle is in the thickness direction of the probe, i.e., the first transverse axis. Since the slit of the first probe penetrates the probe body along the first transverse axis, the probe body is bent along the second transverse axis (i.e., the axis defining the width) during use. A probe with a square cross-section not only better matches the shape of the probe contact area of ​​the electronic test device, but also the width of the probe body is not greater than the thickness, which is beneficial to its elastic deformation effect when bent along the second transverse axis. A probe with a rectangular cross-section has a width of less than its thickness, which makes its elastic deformation effect when bent along the second transverse axis even better. Furthermore, the width of the probe body is less than or equal to its thickness, which allows the probe body to have sufficient thickness to maintain a certain current carrying capacity.

[0032] Preferably, the first probe and the second probe are made of different materials with different hardness.

[0033] Accordingly, the first probe and the second probe can be made of materials with different hardness. For example, the second probe with a smaller cross-sectional area can be made of a harder material to slow down its tip wear rate, which also helps to make the tip wear rates of the first and second probes consistent or similar.

[0034] More preferably, the material hardness of the second probe is greater than that of the first probe.

[0035] In this way, the second probe with a smaller total cross-sectional area is made of a harder material, which can slow down its tip wear rate and help to make the tip wear rates of the first and second probes consistent or similar.

[0036] Preferably, at least one bump group is provided in the slit of the first probe, the bump group including two bumps, the two bumps protruding from two adjacent pieces facing each other.

[0037] In this way, when the probe body of the first probe is subjected to load and bends elastically, the two protrusions facing each other in the slit will abut against each other, thus preventing adjacent probe bodies from contacting each other and wearing out, thereby improving the service life of the first probe. Moreover, by having the two protrusions facing each other abut against each other, the probe bodies can maintain a consistent yaw direction and a certain distance, which is helpful for the electrical performance of high-frequency and high-speed testing.

[0038] Preferably, the resistance values ​​of the first probe and the second probe are different.

[0039] Accordingly, the first probe and the second probe can be designed to have different resistance values ​​by means of their material, shape, size, etc., so that they can be used for different currents to meet the testing requirements of different probe contact areas. At the same time, the first probe and the second probe can still be designed so that their contact force can make their tip wear rate consistent or similar, and / or produce consistent or similar needle mark area ratios for the probe contact areas they contact.

[0040] More preferably, the resistance value of the first probe is less than the resistance value of the second probe.

[0041] Accordingly, the first probe can be used for larger currents, which can meet the large current requirements of the larger probe contact area, and the larger probe contact area can withstand the large contact force of the first probe without being easily damaged; the second probe can be used for smaller currents, which can meet the small current requirements of the smaller probe contact area, and the smaller contact force of the second probe can avoid damaging the smaller probe contact area.

[0042] Preferably, the current withstand values ​​of the first probe and the second probe are different.

[0043] Accordingly, the first probe and the second probe can be designed to have different current withstand values ​​by means of their material, shape, size, etc., so as to meet the current requirements of different probe contact areas. At the same time, the first probe and the second probe can still be designed so that their contact force can make their tip wear rate consistent or similar, and / or produce consistent or similar needle mark area ratios for the probe contact areas they contact.

[0044] Preferably, the resistivity of the first probe and the second probe are different.

[0045] Accordingly, the first probe and the second probe can be made of different materials with different resistivity, so as to achieve the optimal design of the first and second probes under different current conditions by means of material differences. For example, the probe with high current requirements uses a low resistivity material to reduce Joule heat loss, while the probe with low current requirements can use a material with better mechanical strength to improve life and accuracy.

[0046] Preferably, the conductivity of the first probe and the second probe are different.

[0047] Accordingly, the first probe and the second probe can be made of different materials with different electrical conductivity, so as to achieve the optimal design of the first and second probes under different current conditions by means of material differences. The higher the electrical conductivity of the material, the easier it is to conduct electricity. The probe with high current requirement can use a material with high electrical conductivity, while the probe with low current requirement can use a material with better mechanical strength to improve life and accuracy.

[0048] The present invention further provides a probe head, which is applied to a probe system for testing an electronic device under test integrated on a semiconductor wafer. The probe head includes an upper guide plate unit, a lower guide plate unit, and a probe unit as described above. The upper guide plate unit includes a plurality of upper guide holes, and the lower guide plate unit includes a plurality of lower guide holes. The tails of the plurality of probes pass through the upper guide holes, the tips of the plurality of probes pass through the lower guide holes, and the bodies of the plurality of probes are all bent along a second transverse axis.

[0049] The present invention further provides a probe card, which is applied to a probe system for testing an electronic device under test integrated on a semiconductor wafer. The probe card includes a probe head as described above, a space converter, and a main circuit board. The space converter is disposed on a lower surface of the main circuit board and includes a lower surface and a plurality of contact pads located on the lower surface. The probe tails of the plurality of probes of the probe head mechanically and electrically contact the contact pads of the space converter.

[0050] The present invention further provides a probe system for testing an electronic device under test integrated on a semiconductor wafer. The probe system includes a fixture for supporting the electronic device under test, a tester, and a probe card as described above. The probe card is electrically connected to the tester to contact the electronic device under test, thereby electrically connecting the tester and the electronic device under test to perform an electrical test procedure.

[0051] Accordingly, the probe head, probe card and probe system provided by the present invention adopt the probe unit as described above, and thus have its advantages and functions. It can use probes with different cross-sectional area to meet the testing requirements of probe contact blocks of different sizes of electronic devices under test, and at the same time avoid the problems of different tip wear rates and excessive differences in the area ratio of the needle marks.

[0052] The detailed structure, features, assembly, and usage of the probe unit, probe head, probe card, and probe system provided by the present invention will be described in the following detailed description of the embodiments. However, those skilled in the art should understand that such detailed descriptions and the specific embodiments listed for implementing the present invention are merely illustrative and not intended to limit the scope of the patent application.

Implementation Method

[0054] The applicant first clarifies that in the embodiments and drawings described below, the same reference numerals denote the same or similar elements or their structural features. It should be noted that the elements and structures in the drawings are for illustrative purposes and are not drawn according to actual scale and quantity; and features of different embodiments can be used interchangeably if feasible in practice. Secondly, when it is stated that an element is disposed on another element, it means that the aforementioned element is directly disposed on the other element, or that the aforementioned element is indirectly disposed on the other element; that is, one or more other elements are disposed between the two elements. Conversely, when it is stated that an element is "directly" disposed on another element, it means that no other elements are disposed between the two elements.

[0055] Please refer to FIG1 first. A first preferred embodiment of the present invention provides a probe system 10, which is used to test a plurality of electronic devices under test 22 integrated on a semiconductor wafer 20. As shown in FIG2, each electronic device under test 22 includes a plurality of probe contact blocks 221, 222. The probe contact blocks 221, 222 can be bumps or contact pads. In the embodiment of the present invention, they are bumps. The probe contact blocks 221, 222 are quite small in size and very numerous. For the sake of simplifying the diagram and facilitating explanation, the probe contact blocks 221, 222 are not shown in FIG1. Figure 2 schematically shows one configuration of probe contact blocks 221 and 222, wherein probe contact block 221 has a larger area and spacing and is configured in a central region 223 of the electronic device under test 22, and probe contact block 222 has a smaller area and spacing and is configured in a peripheral region 224 of the electronic device under test 22.

[0056] The probe system 10 includes a fixture 11 for supporting the electronic device under test 22, a tester 12, and a probe card 13. The probe card 13 includes a main circuit board 14, a space transformer 15 (ST), and a probe head 16 (PH). The probe head 16 includes multiple probes (described in detail below) for contacting the probe contact blocks 221 and 222 of the electronic device under test 22. For the sake of simplicity and ease of explanation, the probes are not shown in Figure 1 and the probe head 16 is only schematically represented by a rectangle. The internal structure of the probe head 16 is shown in other figures. The main circuit board 14 is electrically connected to the test machine 12. The space converter 15 is located between the probe head 16 and the lower surface 141 of the main circuit board 14, and is used to perform spatial conversion between the probe of the probe head 16 and the conductive contacts (not shown) on the lower surface 141 of the main circuit board 14. That is, the lower surface 151 of the space converter 15 is provided with a plurality of contact pads 153 for electrical contact of the probe (as shown in Figure 3), and the spacing between them is smaller than the distance between the contact pads (not shown) on the upper surface 152 of the space converter 15 for electrical connection of the main circuit board 14. In this way, when the probe of the probe card 13 contacts the probe contact blocks 221, 222 of the electronic test device 22, the test machine 12 is electrically connected to the electronic test device 22 through the probe card 13, so that an electrical test procedure can be performed to test the electrical properties of the electronic test device 22. More specifically, the present invention provides a method for testing an electronic device under test 22, comprising: (a) providing a probe system 10 as described above; (b) positioning a probe tip 16 relative to the electronic device under test 22; and (c) pressing the probe tip 16 against the electronic device under test 22 such that the probe of the probe tip 16 contacts the probe contact areas 221, 222 of the electronic device under test 22, and detecting the electronic characteristics of the electronic device under test 22.

[0057] As shown in Figure 3, the probe head 16 includes an upper guide plate unit 31, a lower guide plate unit 32, and a probe unit 33 disposed within the upper and lower guide plate units 31 and 32. The probe unit described in this invention refers to a collection of probes used to contact the probe contact areas 221 and 222 of an electronic test device 22. It includes a plurality of first probes 40A for contacting the probe contact area 221 and a plurality of second probes 40B for contacting the probe contact area 222. For simplicity and ease of explanation, only one first probe 40A and one second probe 40B are schematically shown in the figures of this invention. Hereinafter, the first and second probes 40A and 40B will represent all probes in the probe unit 33 for description. However, the probe unit of this invention is not limited to all probes having the structural features of the first and second probes described below.

[0058] In this embodiment, the upper and lower guide plate units 31 and 32 each contain only one plate body. However, the upper guide plate unit 31 and / or the lower guide plate unit 32 may also be composed of a plurality of stacked plates. The edges of the upper and lower guide plate units 31 and 32 may have protruding structures and be directly connected to each other, or a hollow middle guide plate (not shown in the figure) may be connected between the upper and lower guide plate units 31 and 32. The upper guide plate unit 31 contains a plurality of upper guide holes 311, and the lower guide plate unit 32 contains a plurality of lower guide holes 321. The first and second probes 40A and 40B have the same length and each includes a needle tail 41 and a needle tip 42 located at their respective ends, and an elongated needle body 43 extending between the needle tail 41 and the needle tip 42. The needle tail 41 is used to mechanically and electrically contact the contact pad 153 of the space converter 15, and the needle tip 42 is used to mechanically and electrically contact the probe contact blocks 221 and 222 of the electronic test device 22. The needle tails 41 of the first and second probes 40A and 40B respectively pass through the upper guide hole 311, the needle tips 42 respectively pass through the lower guide hole 321, and the needle body 43 is located in an accommodating space 34 between the upper and lower guide plate units 31 and 32.

[0059] In this embodiment, the first and second probes 40A and 40B are both square, meaning that the cross-sectional shape of each part is square. For example, Figure 4 shows that the outer contour of the needle body 43 of the first and second probes 40A and 40B is square. Furthermore, each part of the first and second probes 40A and 40B can define a thickness along a first transverse axis (X-axis), a width along a second transverse axis (Y-axis), and a cross-sectional area on an imaginary plane (XY plane) parallel to the first and second transverse axes. For example, Figure 4 shows the widths W1 and W2 and the thicknesses T1 and T2 of the needle body 43 of the first and second probes 40A and 40B. In this embodiment, W1=T1 and W2=T2. In addition, the needle body 43 of the first and second probes 40A and 40B in this embodiment has a lamellar shape, which is commonly referred to as a comb-shaped needle. In detail, the needle body 43 includes at least one slit 431 extending along its longitudinal direction (parallel to the Z-axis in Figure 3). The slit 431 penetrates the needle body 43 along a first transverse axis (X-axis), making the needle body 43 hollow and defining at least two pieces 432 by the at least one slit 431. The at least two pieces 432 are separated from each other along a second transverse axis (Y-axis), that is, the at least two pieces 432 are spaced apart along the second transverse axis (Y-axis). The sum of the cross-sectional areas of the at least two pieces 432 is defined as a total cross-sectional area. In this embodiment, each probe's needle body 43 has only a single slit 431, thus defining two pieces 432, and the total cross-sectional area is the sum of the cross-sectional areas of the two pieces 432. If the needle body 43 has two slits 431, then three pieces 432 will be defined, and the total cross-sectional area will be the sum of the cross-sectional areas of the three pieces 432, and so on.

[0060] During the assembly of the probe head 16, the upper and lower guide plate units 31 and 32 are initially positioned relative to each other but not yet fixed. At this time, the upper guide hole 311 is coaxially aligned with the lower guide hole 321, and the first and second probes 40A and 40B pass through the coaxially aligned upper guide hole 311 and lower guide hole 321 in a straight line, as shown in Figure 3. After the probes are inserted, the upper and lower guide plate units 31 and 32 will move relative to each other along the second transverse axis (Y-axis), causing the upper guide hole 311 and lower guide hole 321 to be offset from each other along the Y-axis, thereby causing the needle bodies 43 of the first and second probes 40A and 40B to bend along the second transverse axis (Y-axis). After the upper and lower guide plate units 31 and 32 have moved relative to each other, they will be fixed together. Therefore, when the probe head 16 is assembled, each piece 432 of the needle body 43 of the first and second probes 40A and 40B will remain bent. Thus, the needle body 43 has good elasticity. When the needle tips 42 of the first and second probes 40A and 40B contact the probe contact blocks 221 and 222 of the electronic test device 22, each piece 432 will be elastically bent under a load.

[0061] In detail, when the first and second probes 40A and 40B are used to test the electronic device under test 22, the probe tips 42 will come into contact with the probe contact areas 221 and 222 of the electronic device under test 22, and then move closer to each other by a test stroke (overdrive, abbreviated as OD; or overtravel, abbreviated as OT), so that the needle bodies 43 of the first and second probes 40A and 40B are compressed and elastically bent, and the probe tips 42 of the first and second probes 40A and 40B press against the probe contact areas 221 and 222 of the electronic device under test 22. During this period, the force exerted by the probe tips 42 of the first and second probes 40A and 40B on the probe contact areas 221 and 222 of the electronic device under test 22 is defined in this invention as the contact force of the first and second probes 40A and 40B. The greater the contact force, the smaller the contact resistance between the needle tip 42 and the probe contact blocks 221, 222 of the electronic test device 22. The contact force is measured by applying OD / OT to the first and second probes 40A and 40B, and measuring the force value of each needle tip 42 acting on a force sensor at this time.

[0062] Furthermore, the aforementioned contact force includes probe deformation force and probe friction force. Probe deformation force refers to the force required for the probe to undergo elastic deformation during the aforementioned test stroke. The probe deformation force depends on many factors, such as the material properties of the probe (e.g., Young's modulus, elastic modulus), the final geometry and dimensions of the probe (e.g., length, thickness, width, etc.). Probe friction force refers to the friction force applied to the probe by the guide plate, such as the friction force applied to the probe by the wall of the aforementioned upper guide hole 311 and / or the wall of the lower guide hole 321. The aforementioned contact force can stably push the needle tails 41 of the first and second probes 40A and 40B against the contact pad 153 of the aforementioned space converter 15, and then buckle the needle bodies 43 of the first and second probes 40A and 40B. This enables an electrical connection to be established between the first and second probes 40A and 40B and the probe contact blocks 221 and 222 of the electronic device under test 22, and thus an electrical connection is established between the probe contact blocks 221 and 222 of the electronic device under test 22 and the first and second probes 40A and 40B to the test machine 12.

[0063] As can be seen from Figures 3 to 5, the first probe 40A and the second probe 40B are respectively a coarse probe and a fine probe. The first probe 40A is used to contact the probe contact area 221 with a larger contact area and spacing, and the second probe 40B is used to contact the probe contact area 222 with a smaller contact area and spacing. More specifically, the total cross-sectional area of ​​the sheet 432 of the first probe 40A is greater than the total cross-sectional area of ​​the sheet 432 of the second probe 40B. The shapes of the sheet 432 of the first probe 40A and the sheet 432 of the second probe 40B are different from each other (although the cross-sectional shapes are both rectangular, the sizes are different, so they are considered to be different shapes), and the shape of the sheet 432 is selected such that the contact force of the first probe 40A is greater than the contact force of the second probe 40B. Preferably, the ratio of the contact force of the first probe 40A to the contact force of the second probe 40B is greater than 1 and less than 4. When the ratio is less than or equal to 1, i.e., the contact force of the first probe 40A is less than or equal to the contact force of the second probe 40B, it is easy to cause insufficient contact force of the first probe 40A, which is used to contact the larger probe contact area 221, thus affecting test stability. Alternatively, it may cause excessive contact force of the second probe 40B, which is used to contact the smaller probe contact area 222, thus easily damaging the second probe 40B and / or the probe contact area 222. Furthermore, it is impossible to avoid a higher tip wear rate. The problem is that the ratio of the needle marks is too large. Secondly, when the ratio is greater than or equal to 4, that is, when the contact force of the first probe 40A is greater than or equal to four times the contact force of the second probe 40B, not only is the difference between the contact force of the first probe 40A and the contact force of the second probe 40B too large, which can easily affect the wear consistency of the first probe 40A and the second probe 40B, it can also easily cause damage to the central area and the outer area of ​​the space converter 15 due to the extremely uneven force, or require additional reinforcement structure design. Moreover, the excessive contact force of the first probe 40A can also easily cause damage to the first probe 40A and / or the probe contact block 221.

[0064] In other words, this embodiment uses different comb-shaped needles, namely the first and second probes 40A and 40B. The outer contour of the cross-section of the needle body 43 is square, but the length and width are different, so they are considered to be different shapes. Specifically, the width W1, thickness T1 and total cross-sectional area of ​​the needle body 43 of the first probe 40A are greater than the width W2, thickness T2 and total cross-sectional area of ​​the needle body 43 of the second probe 40B. In addition, the contact force of the first probe 40A on the needle contact area 221 is greater than the contact force of the second probe 40B on the needle contact area 222. The different comb-shaped needles can be mixed in the following ways: the first and second probes 40A and 40B can both have a single slit 431 and two pieces 432 (as provided in this embodiment); or the second probe 40B can have a single slit 431 and two pieces 432, and the first probe 40A can have two slits 431 and three pieces 432, or more than two slits 431 and more than three pieces 432; or the second probe 40B can have two slits 431 and three pieces 432, and the first probe 40A can have a single slit 431 and two pieces 432, or two slits 431 and three pieces 432, or more than two slits 431 and more than three pieces 432; and so on.

[0065] Accordingly, the width and thickness of the first and second probes 40A and 40B can be designed to match the size and spacing of the probe contact areas 221 and 222 that they need to contact. The rigidity of the probe can be appropriately reduced by the design of the slits 431 of the probe body 43 (design width, number, etc.), thereby appropriately reducing the contact force of the probe. This allows the first and second probes 40A and 40B to meet the testing requirements of their corresponding probe contact areas 221 and 222 in various aspects. Specifically, the total cross-sectional area of ​​the sheet 432 of the first probe 40A is larger, which can meet the high current requirements of the larger probe contact area 221. The larger probe contact area 221 can also withstand the larger contact force of the first probe 40A without being easily damaged. The total cross-sectional area of ​​the sheet 432 of the second probe 40B is smaller, which can meet the low current requirements of the smaller probe contact area 222. The smaller contact force of the second probe 40B can also avoid damaging the smaller probe contact area 222. In other words, the sheet bodies 432 of the first probe 40A and the second probe 40B have different thickness-to-width ratios in geometry. This difference in shape results in different total cross-sectional areas, and further causes different contact force performance. Specifically, the sheet bodies 432 of the first probe 40A and the second probe 40B may be formed with different lengths, and / or the sheet bodies 432 of the first probe 40A and the second probe 40B may be formed with different thicknesses, and / or the sheet bodies 432 of the first probe 40A and the second probe 40B may be formed with different widths.

[0066] More importantly, the present invention can, through the dimensional design of the first and second probes 40A and 40B, such as width, thickness, slit width 431, total cross-sectional area of ​​sheet 432, etc., harmonize the first and second probes 40A and 40B to achieve substantially equal tip abrasion rates and / or substantially equal needle mark area ratios. Substantially equal as described in the present invention is defined as a difference of less than or equal to 20%. In other words, by designing the dimensions of the first and second probes 40A and 40B, the ratio of contact force to contact area of ​​the first and second probes 40A and 40B is made consistent or similar, so that the tip wear rate of the first and second probes 40A and 40B is consistent or similar, thereby making the first and second probes 40A and 40B maintain consistent or similar lengths; and / or making the first and second probes 40A and 40B produce consistent or similar needle mark area ratios for the large protrusion (i.e., probe contact area 221) and the small protrusion (i.e., probe contact area 222) they contact, so that the large protrusion and the small protrusion have consistent or similar heights after testing.

[0067] In detail, since the probe contact blocks 221 and 222 in the embodiments of the present invention are protrusions, the probe contact blocks 221 and 222 are respectively defined as the first protrusion 51 and the second protrusion 52. The maximum cross-sectional area of ​​the first protrusion 51 (i.e., the cross-sectional area of ​​its bottom 511) is greater than the maximum cross-sectional area of ​​the second protrusion 52 (i.e., the cross-sectional area of ​​its bottom 521). When the tip 42 of the first probe 40A and the tip 42 of the second probe 40B press against the first protrusion 51 and the second protrusion 52 respectively, causing the needle body 43 of the first probe 40A and the needle body 43 of the second probe 40B to bend elastically under load, the tips 42 of the first and second probes 40A and 40B will respectively flatten the first and second protrusions 51 and 52 locally to produce planar needle marks 513 and 523, as shown in FIG6 (side view). The area of ​​the needle mark 513 formed by the first probe 40A on the first protrusion 51 is fixed. The area of ​​the first needle mark 523 formed by the second probe 40B on the second protrusion 52 is defined as a first needle mark area. The area of ​​the needle mark 523 formed by the second probe 40B on the second protrusion 52 is defined as a second needle mark area. The area ratio of the needle marks generated by the first probe 40A is the ratio of the area of ​​the first needle mark (i.e., the area of ​​needle mark 513) to the maximum cross-sectional area of ​​the first protrusion 51 (i.e., the cross-sectional area of ​​the bottom 511). The area ratio of the needle marks generated by the second probe 40B is the ratio of the area of ​​the second needle mark (i.e., the area of ​​needle mark 523) to the maximum cross-sectional area of ​​the second protrusion 52 (i.e., the cross-sectional area of ​​the bottom 521). In this embodiment, the "needle mark area ratio" refers to the ratio of the probe contact area (needle mark area) formed by the needle mark on the top of the protrusion when viewed from the top view (top view) of the electronic test device 22 to the maximum cross-sectional area of ​​the protrusion. In other words, the needle mark area ratio is a parameter that measures the degree of indentation of the probe corresponding to the protrusion, thereby comparing the deformation range produced by different needle marks corresponding to protrusions of different sizes. Generally, the maximum cross-sectional area of ​​a protrusion is defined based on its size, that is, the nominal size (specification) set during protrusion design. For example, if the protrusion is a circular protrusion with a diameter of 20 micrometers, its maximum cross-sectional area can be considered as the area of ​​a circle, calculated based on that diameter. In this embodiment, the maximum cross-sectional area of ​​the protrusion is defined by its diameter, width, or equivalent geometric dimensions (e.g., projected area), used as a reference for the needle mark area ratio. In some embodiments, the needle mark area can also be inferred from the collapse height of the protrusion after probe contact. Generally, the ratio of the first needle mark area to the maximum cross-sectional area of ​​the first protrusion 51 and / or the ratio of the second needle mark area to the maximum cross-sectional area of ​​the second protrusion 52 is preferably less than 25%.

[0068] It is worth mentioning that the first and second probes 40A and 40B can also be used to contact the first protrusion 51 and the second protrusion 52 of substantially the same size. As shown in FIG13, the tip 42 of the first probe 40A is used to press against a plurality of first protrusions 51 simultaneously, for example, four first protrusions 51 arranged in a matrix (FIG13 only shows two of the first protrusions 51). The plurality of first protrusions 51 are all configured to transmit a first signal, which can be a power signal or a ground signal. The tip 42 of the second probe 40B is used to press against a single second protrusion 52. The second protrusion 52 is configured to transmit a second signal, which is a test signal different from the first signal, that is, a non-power signal or a non-ground signal. Therefore, even if the dimensions of each first protrusion 51 and second protrusion 52 are substantially the same, the first probe 40A with a larger contact force is used to press against multiple first protrusions 51 at the same time, while the second probe 40B with a smaller contact force is used to press against a single second protrusion 52. Thus, the wear rate of the tips of the first and second probes 40A and 40B can still be made consistent or similar through the size design, and / or the first protrusion 51 and the second protrusion 52 can produce consistent or similar needle mark area ratios.

[0069] Furthermore, the first probe 40A and the second probe 40B can also be made of materials with different hardness. The difference in hardness between the first probe 40A and the second probe 40B helps to harmonize the tip wear rates of the first and second probes 40A and 40B to be substantially equal. For example, the second probe 40B, with its smaller total cross-sectional area, can be made of a harder material to slow down its tip wear rate. In this embodiment, the 'different hardness' of the first probe 40A and the second probe 40B refers to the fact that the probe systems of the two probes are composed of materials with different hardnesses. The hardness can be measured according to Vickers hardness (HV) or other standard hardness testing methods and has certain differences. By configuring materials with different hardnesses, the wear rates of probes of different sizes can be coordinated, maintaining consistency and long-term stability during testing.

[0070] Furthermore, the first probe 40A and the second probe 40B may also have different resistance values, and / or different current-carrying capacity values, and / or different resistivity, and / or different conductivity, in order to meet the testing requirements of different probe contact areas. At the same time, the first probe 40A and the second probe 40B may still be designed such that their contact force can make their tip wear rate consistent or similar, and / or produce consistent or similar needle mark area ratios for the probe contact areas they contact.

[0071] In this embodiment, the resistance value of the probe refers to the electrical impedance generated by the conductive material constituting the probe under its designed length and cross-sectional area, when current flows through it. It is typically expressed in ohms (Ω). In other words, the resistance value is a comprehensive representation of the probe's geometric dimensions and its material properties (resistivity), suitable for comparing the conductivity of probes of different sizes or materials. The resistance value of the probe can be calculated using the formula R=ρ(L / A), where R is the resistance value of the probe, L is the length of the probe, A is the cross-sectional area of ​​the probe, and ρ is the resistivity of the probe material. For example, when the first probe 40A and the second probe 40B are made of the same material but have different dimensions, their resistance values ​​will mainly be due to differences in geometric dimensions. Generally, a larger probe with a larger cross-sectional area (i.e., the first probe 40A) has a lower resistance value, while a smaller probe with a smaller cross-sectional area (i.e., the second probe 40B) has a higher resistance value.

[0072] The current withstand value referred to in this embodiment refers to the maximum current that a single probe can continuously withstand under stable operating conditions without overheating, structural damage, or material degradation, usually expressed in milliamperes (mA). In other words, the current withstand value is a comprehensive indicator of structural dimensions, material thermal conductivity, and heat dissipation environment conditions. In this embodiment, the current withstand capability of the probe is affected by factors such as the probe's cross-sectional area, length, material melting point, and thermal conductivity. Generally speaking, a thicker probe with a larger cross-sectional area has better heat dissipation efficiency and current carrying capacity, so its current withstand value is usually higher than that of a thinner probe. For example, if the first probe 40A is a thicker probe and the second probe 40B is a thinner probe, then under the same material and test conditions, the current withstand capability of the first probe 40A is expected to be higher than that of the second probe 40B, that is, the first probe 40A can withstand a larger current without thermal damage.

[0073] In this embodiment, resistivity refers to the ability of a material to impede the conduction of current. It is an inherent physical property of the material and is usually measured in ohm-meters (Ω·m). A higher resistivity means that the material impedes the current more, while a lower resistivity indicates better conductivity. On the other hand, conductivity is the reciprocal of resistivity and is also the ability of a material to conduct current, usually measured in Siemens per meter (S / m). The higher the conductivity, the easier the material is to conduct electricity. In this invention, if the first probe 40A and the second probe 40B have different resistivities or conductivity, it means that the first and second probes 40A and 40B are made of different conductive materials. This material difference can be used to achieve optimal design of the probes under different current conditions. For example, probes with high current requirements use low resistivity materials to reduce Joule heat loss, while probes with low current requirements can use materials with better mechanical strength to improve lifespan and accuracy.

[0074] The first probe 40A and the second probe 40B in this invention are not limited to squares, that is, the cross-sectional shape of each part is not limited to a square. For example, as shown in Figure 7, the outer contour of the cross-section of the needle body 43 of the first and second probes 40A and 40B is rectangular. The width of the needle body 43 of each probe is less than its thickness, that is, W1 < T1, W2 < T2. In other words, the long side of the rectangle is the thickness direction of the probe, that is, the first transverse axis (X-axis). This design can make the elastic deformation effect of the needle body 43 bending along the second transverse axis (Y-axis) better, and can make the needle body 43 have sufficient thickness to maintain a certain current carrying capacity.

[0075] Furthermore, in the first and second probes 40A and 40B shown in Figure 7, since the total cross-sectional area of ​​the sheet 432 of the first probe 40A is greater than that of the sheet 432 of the second probe 40B, it indicates that the first probe 40A is a probe with a larger needle diameter, while the second probe 40B is a probe with a smaller needle diameter. Generally speaking, probes with smaller needle diameters also have relatively smaller spacing between them, so their needle diameter (width and / or thickness) cannot be arbitrarily expanded to avoid problems such as probes short-circuiting due to excessively small probe spacing, or insufficient wall thickness caused by excessively small spacing of the guide holes in the guide plate. Based on this design consideration, the ratio of the width W1 to the thickness T1 of the needle body 43 of the first probe 40A is less than the ratio of the width W2 to the thickness T2 of the needle body 43 of the second probe 40B, that is, W1 / T1 < W2 / T2. Alternatively, the outer contour of the cross-section of the first probe 40A can be rectangular, and the outer contour of the cross-section of the second probe 40B can be square, achieving the aforementioned structural features of the ratio relationship. In this way, while maintaining a larger cross-sectional area to withstand higher current, the needle body 43 of the first probe 40A, due to its smaller width-to-thickness ratio, possesses better elastic deformation effects when bending along the second transverse axis. This allows it to produce consistent or similar elastic deformation responses with the second probe 40B, which has a smaller cross-sectional area, thereby ensuring consistent or similar probe measurement performance.

[0076] Furthermore, the comb-shaped needle in this invention may also have the structural features shown in Figures 8 and 9. Here, the first probe 40A is used as an example. At least one set of protrusions 433 may be provided within its slit 431. The protrusion set 433 includes two protrusions 434, which protrude from adjacent plates 432 facing each other. Thus, when the tip 42 of the first probe 40A presses against the probe contact area 221 of the electronic test device 22, causing the plates 432 of the needle body 43 to bend elastically under load, the two protrusions 434 facing each other within the slit 431 will abut against each other. This prevents adjacent plates 432 from contacting each other and causing wear, thereby increasing the probe's service life. Moreover, by having the two protrusions 434 facing each other abut against each other, the plates 432 can maintain a consistent yaw direction and a certain distance, which is beneficial for high-frequency, high-speed electrical performance testing. The bump 434 is disposed between adjacent pads 432 and is arranged facing each other. When the probe is bent, the bump 434 will make contact first, thereby limiting the bending direction and angle of the pad 432. This can prevent the pad 432 from asymmetrically swaying under eccentric force, ensuring that the contact angle between the probe tip and the pad or bump is stable, which helps to ensure consistent needle marks and contact resistance.

[0077] Please refer to Figure 10. The probe unit 35 provided in a second preferred embodiment of the present invention is similar to the aforementioned probe unit 33, except that the difference lies in the shape of the tip 42 of the first probe 40A.

[0078] In detail, in this embodiment, the tip 42 of the first probe 40A includes a base 421 connected to the body 43 and an end portion 422 connected to the base 421. The cross-sectional shape of the base 421 is the same as or equivalent to the outer contour shape of the cross-section of the body 43, where "equivalent" means that the area difference is ±20%. Compared to the base 421, the end portion 422 is reduced in width and / or thickness, such that the cross-sectional area of ​​the end portion 422 is smaller than that of the base 421. The cross-sectional area of ​​the end portion 422 is preferably 20-60% of the cross-sectional area of ​​the base 421, and more preferably 50% of the cross-sectional area of ​​the base 421. This end portion 422 is the actual contact tip that enables the tip 42 of the first probe 40A to actually contact the electronic test device, that is, the end portion 422 refers to the part that is actually used to contact the probe contact block 221 of the electronic test device 22. As shown in Figure 10, the end 422 is preferably eccentric relative to the center of the first probe 40A, or eccentric relative to the base 421. This end 422 can be obtained by removing material asymmetrically (unilaterally / unidirectionally) from one side of the tip 42 of the first probe 40A.

[0079] Under this structural design, the shape of the sheet 432 of the first and second probes 40A and 40B can still be selected such that the contact force of the first probe 40A, which has a larger total cross-sectional area, is greater than the contact force of the second probe 40B, which has a smaller total cross-sectional area. Preferably, the ratio of the contact force of the first probe 40A to the contact force of the second probe 40B is greater than 1 and less than 4. Furthermore, the tip 42 of the first probe 40A has a thinned and / or narrowed end 422, which helps to adjust the tip wear rate of the first probe 40A and the ratio of the resulting needle mark area, thereby making the tip wear rates of the first and second probes 40A and 40B consistent or similar, and / or making the first and second probes 40A and 40B produce consistent or similar needle mark area ratios. In particular, it is easier to harmonize the first and second probes 40A and 40B so that the ratios of the needle mark areas they produce are substantially equal.

[0080] Furthermore, even if the cross-sectional area of ​​the tip 422 of the first probe 40A is reduced, the cross-sectional area of ​​the tip 422 of the first probe 40A can still be made larger than the cross-sectional area of ​​the tip 42 of the second probe 40B. This not only allows for the corresponding larger area of ​​the probe contact block 221 and the smaller area of ​​the probe contact block 222, but also helps to make the tip wear rates of the first and second probes 40A and 40B consistent or similar, and to make the first and second probes 40A and 40B produce consistent or similar needle mark area ratios. Preferably, the ratio of the cross-sectional area of ​​the tip 422 of the first probe 40A to the cross-sectional area of ​​the tip 42 of the second probe 40B is greater than 1 and less than 4. When the ratio is less than 1, that is, when the cross-sectional area of ​​the tip 422 of the first probe 40A is less than the cross-sectional area of ​​the tip 42 of the second probe 40B, it is impossible to avoid the problems of different tip wear rates and excessively large differences in the needle mark area ratio. Secondly, when the ratio is greater than or equal to 4, that is, when the cross-sectional area of ​​the tip 422 of the first probe 40A is greater than or equal to the cross-sectional area of ​​the tip 42 of the second probe 40B, the difference is too large, which not only easily affects the wear consistency of the first probe 40A and the second probe 40B, but also makes it difficult to avoid the problem of excessively large differences in the needle mark area ratio.

[0081] Please refer to Figures 11 and 12. The main difference between the probe unit 36 ​​provided in the third preferred embodiment of the present invention and the aforementioned embodiments is that the first probe 40A' in this embodiment is also a comb-shaped needle, but the second probe 40B' is a non-comb-shaped needle, and the needle body 43 of the second probe 40B' is inwardly recessed, as detailed below.

[0082] In this embodiment, the first probe 40A' is similar in shape and size to the second probe 40B in the aforementioned embodiments. The needle body 43 of the first probe 40A' includes at least one slit 431 extending along its longitudinal direction. The slit 431 penetrates the needle body 43 of the first probe 40A' along the first transverse axis (X-axis), so that the needle body 43 of the first probe 40A' is hollow and is defined by the at least one slit 431 as at least two pieces 432. The at least two pieces 432 are separated from each other along the second transverse axis (Y-axis) and can be elastically bent under load. Similar to the comb-shaped needle described in the first preferred embodiment, in this embodiment, the width W3 of the needle body 43 of the first probe 40A' can be equal to the thickness T1 (i.e., the outer contour of the cross-section is square), or the width W3 can be less than the thickness T1 (i.e., the outer contour of the cross-section is rectangular) to improve the elastic deformation effect of the needle body 43 when bending along the second transverse axis, and to make the needle body 43 have sufficient thickness to be less prone to breakage. In this embodiment, the first probe 40A' can also be provided with a bump group 433 as shown in Figures 8 and 9, thereby improving the service life of the probe and the electrical performance of high-frequency and high-speed testing.

[0083] In this embodiment, the tail 41 and tip 42 of the second probe 40B' are similar in shape and size to the tail 41 and tip 42 of the first probe 40A'. However, the body 43 of the second probe 40B' is solid without a slit, and the width and / or thickness of the body 43 of the second probe 40B' are reduced compared to the tail 41 and tip 42, so that the cross-sectional area of ​​the body 43 of the second probe 40B' is smaller than the cross-sectional area of ​​the tail 41 and smaller than the cross-sectional area of ​​the tip 42 of the second probe 40B'. The inward shrinkage of the body 43 of the second probe 40B' compared to the tail 41 and tip 42 can be a single-sided shrinkage, a double-sided shrinkage, a four-sided shrinkage, etc. Thus, the needle body 43 of the second probe 40B' can also be elastically bent between the upper and lower guide plate units 31 and 32, and has good elasticity, and can be elastically bent under load when the needle tip 42 presses against the electronic test device 22.

[0084] In other words, this embodiment uses a combination of comb-shaped needles and non-comb-shaped needles, that is, the first and second probes 40A' and 40B' have square outer contours of their needle bodies 43, but their lengths and widths are different, so they are also considered to be different shapes. Specifically, the width W3 and thickness T3 of the needle body 43 of the first probe 40A' are greater than the width W4 and thickness T4 of the needle body 43 of the second probe 40B', and the total cross-sectional area of ​​the sheet 432 of the first probe 40A' is greater than the cross-sectional area of ​​the needle body 43 of the second probe 40B'. Furthermore, the shape of the sheet 432 of the first probe 40A' is selected such that the contact force of the first probe 40A' is greater than the contact force of the second probe 40B'.

[0085] Accordingly, the first and second probes 40A' and 40B' of this embodiment can also meet the testing requirements of their corresponding probe contact areas 221 and 222 in various aspects through their size design. Specifically, the total cross-sectional area of ​​the sheet 432 of the first probe 40A' is larger, which can meet the high current requirements of the larger probe contact area 221, and the larger probe contact area 221 can withstand the larger contact force of the first probe 40A' without being easily damaged. The cross-sectional area of ​​the needle body 43 of the second probe 40B' is smaller, which can meet the low current requirements of the smaller probe contact area 222, and the smaller contact force of the second probe 40B' can avoid damaging the smaller probe contact area 222. More importantly, this embodiment can also adjust the first and second probes 40A' and 40B' to have substantially equal needle tip wear rates and / or substantially equal needle mark area ratios through the size design of the first and second probes 40A' and 40B'. Furthermore, the first probe 40A' and the second probe 40B' can also be made of materials with different hardness. This difference in hardness helps to harmonize the first and second probes 40A' and 40B' to achieve substantially equal tip wear rates. In this embodiment, the "different hardness" of the first probe 40A' and the second probe 40B' refers to the fact that their probe systems are composed of materials with different hardnesses. The hardness can be measured using Vickers hardness (HV) or other standard hardness testing methods and will have certain differences. By configuring materials with different hardnesses, the wear rates of probes of different sizes can be coordinated, maintaining consistency and long-term stability during testing.

[0086] In the embodiments described in this invention, "different shapes" refers to identifiable differences in the geometric shape, size ratio, or cross-sectional distribution of the first and second probes. For example, even if the cross-sections of the first and second probes are both rectangular, as long as their thickness and width (i.e., the dimensions defined by the first and second transverse axes) are different, they constitute "different shapes." Furthermore, if the number of probes is the same, but their distribution, number of slits, thickness-to-width ratio, and / or symmetrical configuration are different, this also falls under the category of "different shapes" as described in this specification. Such design differences help adjust the contact force distribution and elastic deformation behavior of each probe, ensuring the testing accuracy and reliability for different probe contact areas (such as large bumps and small pads).

[0087] Finally, it must be stated again that the constituent elements disclosed in the above-mentioned embodiments of the present invention are merely illustrative examples and are not intended to limit the scope of this application. Substitutions or variations of other equivalent elements should also be covered by the scope of the patent application of this application. [Simplified Explanation of the Diagram]

[0053] Figure 1 is a schematic diagram of a probe system and a semiconductor wafer provided in a first preferred embodiment of the present invention. Figure 2 is a top view of an electronic test device on a semiconductor wafer. Figure 3 is a partial cross-sectional view of a probe head and a space converter of the probe system provided in the first preferred embodiment of the present invention. Figure 4 is a cross-sectional view of the needle bodies of the first and second probes of the probe head. Figure 5 is a partial schematic diagram of the first and second probes and the electronic test device. Figure 6 is a partial schematic diagram of the electronic test device, showing the state of the first and second bumps of the electronic test device after being pressed by the first and second probes respectively. Figure 7 is similar to Figure 4, but shows the first and second probes in a different state. Figure 8 is a schematic diagram of another first probe in a different state. Figure 9 is a cross-sectional view along section line 9-9 of Figure 8. Figure 10 is a partial cross-sectional view of a probe head provided in a second preferred embodiment of the present invention. Figure 11 is a partial cross-sectional view of a probe head provided in a third preferred embodiment of the present invention. Figure 12 is a cross-sectional view of the needle body of the first and second probes of the probe head provided in the third preferred embodiment of the present invention. Figure 13 is a schematic diagram of the first and second probes used to contact the first and second protrusions of substantially the same size.

Claims

1. A probe unit for contacting a plurality of probe contact blocks of an electronic test device integrated on a semiconductor wafer; the probe unit comprising: a plurality of probes having the same length, each probe including a tail and a tip located at its two ends, and a body located between the tail and the tip, the body including at least one slit extending along its longitudinal direction, the slit penetrating the body along a first transverse axis, such that the body is hollow and defined by the at least one slit as at least two pieces, the at least two pieces being separated from each other along a second transverse axis and elastically bending under a load, each piece defining a cross-sectional area on an imaginary plane parallel to the first and second transverse axes, the sum of the cross-sectional areas of the at least two pieces of each probe being defined as a total cross-sectional area; wherein... The probes include a first probe and a second probe, the total cross-sectional area of ​​the sheet of the first probe is greater than the total cross-sectional area of ​​the sheet of the second probe, the shape of the sheet of the first probe is different from the shape of the sheet of the second probe, and the shape of the sheet is selected such that the contact force of the first probe is greater than the contact force of the second probe.

2. The probe unit as claimed in claim 1, wherein the ratio of the contact force of the first probe to the contact force of the second probe is greater than 1 and less than 4.

3. The probe unit as claimed in claim 1, wherein the body of each probe can define a thickness in the first transverse axis and a width in the second transverse axis, and the width of the body of each probe is less than or equal to the thickness.

4. The probe unit as claimed in claim 1, wherein the tip of the first probe includes a base connected to the body of the probe and an end connected to the base, the end being used to contact the probe contact area of ​​the electronic device under test, the base and the end being able to define a cross-sectional area on an imaginary plane parallel to the first transverse axis and the second transverse axis, respectively, the cross-sectional area of ​​the end being smaller than the cross-sectional area of ​​the base.

5. The probe unit as claimed in claim 4, wherein the tip of the second probe can define a cross-sectional area on an imaginary plane parallel to the first transverse axis and the second transverse axis, and the cross-sectional area of ​​the end of the tip of the first probe is greater than or equal to the cross-sectional area of ​​the tip of the second probe.

6. The probe unit as claimed in claim 5, wherein the ratio of the cross-sectional area of ​​the tip of the first probe to the cross-sectional area of ​​the tip of the second probe is greater than 1 and less than 4.

7. The probe unit as claimed in claim 1, wherein the plurality of probe contact blocks of the electronic test device includes a first protrusion and a second protrusion, the maximum cross-sectional area of ​​the first protrusion being greater than the maximum cross-sectional area of ​​the second protrusion; when the tip of the first probe and the tip of the second probe press against the first protrusion and the second protrusion respectively, causing the body of the first probe and the body of the second probe to bend elastically under load, the first probe forms a first needle mark area on the first protrusion, the second probe forms a second needle mark area on the second protrusion, and the ratio of the first needle mark area to the maximum cross-sectional area of ​​the first protrusion and the ratio of the second needle mark area to the maximum cross-sectional area of ​​the second protrusion are equal.

8. The probe unit as claimed in claim 1, wherein the plurality of probe contact blocks of the electronic device under test include a plurality of first bumps and a second bump, each of the first bumps and the second bump being of the same size; the tip of the first probe is used to press against the plurality of first bumps simultaneously, each of the plurality of first bumps being configured to transmit a first signal, the first signal being one of a power signal and a ground signal; the tip of the second probe is used to press against the second bump, the second bump being configured to transmit a second signal, the second signal being a test signal different from the first signal.

9. The probe unit as claimed in claim 1, wherein the body of each probe can define a thickness in the first transverse axis and a width in the second transverse axis, and the ratio of the width to the thickness of the body of the first probe is less than the ratio of the width to the thickness of the body of the second probe.

10. The probe unit as claimed in claim 1, wherein the first probe and the second probe are made of different materials with different hardness.

11. The probe unit as claimed in claim 10, wherein the material hardness of the second probe is greater than that of the first probe.

12. The probe unit as claimed in claim 1, wherein at least one bump group is provided in the slit of at least the first probe, the bump group comprising two bumps that protrude from two adjacent plates facing each other.

13. A probe unit for contacting a plurality of probe contact blocks of an electronic test device integrated on a semiconductor wafer; the probe unit comprising: a plurality of probes having the same length, each probe comprising a tail and a tip located at its two ends, and a body located between the tail and the tip, the probes including: a first probe, the body of which includes at least one slit extending along its longitudinal direction, the slit penetrating the body of the first probe along a first transverse axis, such that the body of the first probe is hollow and defined by the at least one slit as at least two pieces, the at least two pieces being separated from each other along a second transverse axis and elastically bending under a load; and a second probe, the body of which is solid and elastically bending under a load; wherein... Each of the probe's tail and tip, each of the first probe's plates, and the second probe's body can each define a cross-sectional area on an imaginary plane parallel to the first and second transverse axes. The sum of the cross-sectional areas of the at least two plates of the first probe is defined as a total cross-sectional area. The total cross-sectional area of ​​the first probe's plates is greater than the cross-sectional area of ​​the second probe's body. The cross-sectional area of ​​the second probe's body is less than the cross-sectional area of ​​the second probe's tail and less than the cross-sectional area of ​​the second probe's tip. The shape of the first probe's plates is selected such that the contact force of the first probe is greater than the contact force of the second probe.

14. The probe unit as claimed in claim 13, wherein the body of the first probe can define a thickness in the first transverse axis and a width in the second transverse axis, and the width of the body of the first probe is less than or equal to the thickness.

15. The probe unit as claimed in claim 13, wherein the first probe and the second probe are made of different materials with different hardness.

16. The probe unit as claimed in claim 15, wherein the material hardness of the second probe is greater than that of the first probe.

17. The probe unit as claimed in claim 13, wherein the slit is provided with at least one bump group, the bump group comprising two bumps that protrude from two adjacent plates facing each other.

18. The probe unit as described in claim 1 or 13, wherein the resistance values ​​of the first probe and the second probe are different.

19. The probe unit as claimed in claim 18, wherein the resistance value of the first probe is less than the resistance value of the second probe.

20. The probe unit as claimed in claim 1 or 13, wherein the first probe and the second probe have different current withstand values.

21. The probe unit as described in claim 1 or 13, wherein the resistivity of the first probe is different from that of the second probe.

22. The probe unit as claimed in claim 1 or 13, wherein the first probe and the second probe have different conductivities.

23. A probe head, used in a probe system for testing an electronic device under test integrated on a semiconductor wafer; the probe head comprising: an upper guide plate unit including a plurality of upper vias; a lower guide plate unit including a plurality of lower vias; and a probe unit as described in claim 1 or 13; wherein, The tails of the multiple probes pass through the upper guide holes, the tips of the multiple probes pass through the lower guide holes, and the bodies of the multiple probes are all bent along the second transverse axis.

24. A probe card for use in a probe system for testing an electronic device under test integrated on a semiconductor wafer; the probe card includes: a probe head as described in claim 23; a space converter; and a main circuit board; wherein, The space transducer is disposed on a lower surface of the main circuit board. The space transducer includes a lower surface and a plurality of contact pads located on the lower surface. The tails of the plurality of probes of the probe head mechanically and electrically contact the contact pads of the space transducer.

25. A probe system for testing an electronic device under test integrated on a semiconductor wafer; the probe system comprising: a fixture for supporting the electronic device under test; a tester; and a probe card as described in claim 24, electrically connected to the tester for contacting the electronic device under test to electrically connect the tester to the electronic device under test, thereby performing an electrical testing procedure.

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