CN114745843A - PCB and probe card - Google Patents

Abstract

The PCB comprises a substrate, wherein at least two golden fingers are arranged on the upper surface of the substrate around the center of the substrate, each golden finger is provided with a test connection point, a device connection area, a first isolation groove and a second isolation groove, the device connection area is positioned in the first isolation groove and is disconnected with the golden finger through the first isolation groove, and the test connection point is positioned in the second isolation groove and is disconnected with the golden finger through the second isolation groove; the device connecting area is provided with at least two first connecting points, the first connecting points are electrically communicated, and at least one first connecting point is electrically connected with the test connecting point; the upper surface of the substrate is also provided with a plurality of second connecting areas around the center of the substrate, and the golden fingers are positioned in the peripheral areas of the second connecting areas. The PCB can be used as a verification board, and the first connecting points on the plurality of golden fingers are connected with components for measurement to obtain the accuracy of the test machine; the PCB can also be used as a substrate of the probe card, and the efficient use of the PCB is improved.

Description

PCB and probe card

Technical Field

The invention belongs to the technical field of semiconductor design and manufacture, and particularly relates to a PCB and a probe card.

Background

In the semiconductor integrated circuit industry, a probe card (probe card) is commonly used to perform auxiliary testing when performing wafer-level electrical testing on a tester.

In the conventional probe card, one end of a probe (probe) is fixed on a PCB (circuit board), and then the probe (probe) is connected to a test machine through the PCB, and the other end of the probe (probe) is in contact with a probe on each test unit (DUT) on a wafer, thereby forming a complete test system. The probe card is used for communicating the testing machine table with the tested structure through pricking the bonding pads. In the use process of the probe card, each tester manufacturer uses slightly different probe cards due to the unique design of the test head.

In order to verify the testing accuracy and testing accuracy of the wafer electrical testing equipment, a series of verification work is usually required before the testing equipment leaves a factory, the verification mode is mainly that a known component is measured, a value measured by the testing equipment is compared with an actual value of the component to see difference, and the closer the measured value is to the actual value, the higher the accuracy of the testing equipment is. The existing probe card can only be used for wafer testing, when testing equipment needs to be verified, an extra PCB verification board is needed to carry out connection testing on components, operation steps are increased, and testing efficiency is reduced.

Meanwhile, the substrate materials of the existing probe card are mainly two, one is all-ceramic material, the price is high, and the electric leakage risk is low; the other is FR4 material, which is relatively inexpensive, but which has a high risk of leakage during use. Because the wafer belongs to a low-leakage product, if the leakage risk of the probe card is higher, the test precision of a test machine table is greatly influenced, and the test result is influenced.

Therefore, it is necessary to provide a PCB and a probe card thereof with multifunction, moderate price and small leakage risk, so as to realize efficient use of the probe card.

Disclosure of Invention

The invention provides a PCB which can realize the multifunctionality of the PCB and can greatly reduce the production cost under the condition of ensuring low electric leakage risk.

The invention also provides a probe card, and the probe card is multifunctional and efficient to use due to the adoption of the PCB.

Other objects and advantages of the present invention will be further understood from the technical features disclosed in the present invention.

In order to achieve one or a part of or all of the above purposes or other purposes, the PCB provided in a technical solution of the present invention includes a substrate, wherein at least two gold fingers are disposed on an upper surface of the substrate around a center of the substrate, each of the gold fingers is provided with a test connection point, a device connection area, a first isolation groove and a second isolation groove, the device connection area is located in the first isolation groove and disconnected from the gold finger through the first isolation groove, and the test connection point is located in the second isolation groove and disconnected from the gold finger through the second isolation groove; the device connection region is provided with at least two first connection points which are electrically connected to each other, and at least one of the first connection points is electrically connected to the test connection point. The PCB can be used as a verification board, and when the PCB is used as the verification board, the PCB can be connected with components through the first connecting points of the device connecting areas on the plurality of golden fingers; the PCB can also be used as a substrate of the probe card, and only the probes are required to be arranged on the PCB so as to be electrically connected with the first connecting points, so that the PCB provided by the technical scheme has multiple functions, and the efficient use of the PCB is improved; in addition, the first isolation groove and the second isolation groove can block the electrical connection between the regions, and the insulating capability is improved. The upper surface of the substrate is also provided with a plurality of second connecting areas around the center of the substrate, and the golden fingers are positioned in the peripheral areas of the second connecting areas. When the PCB board uses as the verification board, if the size of components and parts is great, when unable direct interlinkage between a plurality of golden fingers, can regard as the intermediate junction point through the second joining region, make components and parts be connected to the second joining region earlier, and then link to each other with other device joining regions.

Further, the device connection region is disposed at an end of each of the gold fingers near a center of the substrate. The technical scheme has the advantages that when the PCB is used as a probe card substrate, because the probe is generally arranged at the center of the substrate and the device connecting area is arranged at one end close to the center of the substrate, the connecting distance between the probe and the device connecting area can be shortened, and adverse effects caused by overlong connecting channels are avoided.

Furthermore, the plurality of second connecting areas are radially arranged outwards to form a plurality of layers by taking the center of the substrate as the center. The arrangement of the multiple layers of second connecting areas can be suitable for connecting components with different sizes.

The second connection region may be a metal layer disposed on the upper surface of the substrate, and each metal layer is not electrically connected to each other. Preferably, the metal layer is provided with a through hole, so that pin welding of components can be facilitated.

The arrangement mode of the second connecting area is the same as that of the golden fingers, so that the neatness and the attractiveness of the PCB are guaranteed, and the operation and the connection of a user are facilitated.

Every be provided with a plurality of test connection points on the golden finger, every the test connection point all dispose alone the correspondence the second isolation tank to through the correspondence the second isolation tank with golden finger disconnection, and at least one first connecting point with a plurality of test connection point electricity are connected. Through the arrangement of a plurality of test connection points, different electrical parameters can be measured simultaneously.

Through holes are formed in the first connecting point, the test connecting point and the golden fingers located in the outer areas of the first isolation groove and the second isolation groove. The through holes can be used for electrically connecting the first connecting points and the test connecting points, can also be used as welding holes of pins of components and parts when being used as a verification plate, and can be used for realizing the electrical connection between the golden fingers on the upper surface and the lower surface of the substrate when the golden fingers on the outer areas of the first isolation groove and the second isolation groove are provided with the golden fingers corresponding to the golden fingers on the upper surface at the lower surface of the substrate, and can also be used as welding holes of the pins of the components and parts.

The lower surface of the substrate is also provided with at least two golden fingers, the golden fingers on the lower surface of the substrate are in one-to-one correspondence with the golden fingers on the upper surface of the substrate, and the through holes in the golden fingers on the outer areas of the first isolation groove and the second isolation groove are electrically connected with the corresponding golden fingers on the upper surface and the lower surface of the substrate.

The substrate is provided with a grounding point. The grounding point can be connected with a grounding pressure point of the test head when in use, and can also be directly connected with a test machine table to realize the grounding protection of the substrate.

The upper surface and the lower surface of the substrate are paved by adopting ceramic materials, and the middle layer positioned between the upper surface and the lower surface is made of FR4 material. Because the ceramic material is expensive and has small influence on the electric leakage of the probe card, and the FR4 material is very cheap and can generate large electric leakage, the electric leakage of the product is not influenced by adopting the design, and the manufacturing cost is greatly saved.

The base plate is provided with a positioning hole or/and a convenient holding device mounting hole; the positioning hole is used for positioning and mounting the PCB, and the convenient holding device mounting hole is used for mounting the convenient holding device. The positioning hole can be used for positioning the probe card position so as to be installed on the probe station; meanwhile, the positioning hole can also be used as a mounting hole of the fixing structure, and the fixing structure such as a bolt can be fixed on the probe station, so that the fixing structure is more firmly mounted, and the pressure point of the test head is more accurate. In addition, the device can be installed through the installation hole of the device, a user can conveniently take and place the PCB, the problem that the probe card is too high in electric leakage due to pollution and damage to the surface of the probe card is avoided, and meanwhile, certain protection effect on parts on the substrate can be achieved.

The substrate is also provided with a direction indication mark. The direction of the probe can be more conveniently determined by a user, and the probe can be positioned and installed more quickly.

The invention also provides a probe card which comprises the PCB, wherein a plurality of probe connection points and a plurality of probes are arranged on a substrate of the PCB, the probes are positioned in the center of the upper surface of the substrate, the probe connection points are distributed around the periphery of the probes, the probes are respectively and electrically connected with the probe connection points, and the probe connection points are respectively and electrically connected with the first connection points.

Compared with the prior art, the invention has the beneficial effects that: the PCB board can realize multifunctional use of the PCB board by arranging the device connecting area, and meanwhile, the base plate is made of mixed materials, so that the electric leakage of the product is not affected, and the manufacturing cost is greatly saved.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive efforts.

FIG. 1 is a diagram illustrating a probe card according to a preferred embodiment of the present invention.

Fig. 2 is a partially enlarged view of fig. 1.

Detailed Description

The foregoing and other technical and scientific aspects, features and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment, which is to be read in connection with the accompanying drawings. Directional terms as referred to in the following examples, for example: up, down, left, right, front or rear, etc., are referred to only in the direction of the attached drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.

A preferred embodiment of the present invention provides a probe card as shown in fig. 1, and fig. 2 shows a partially enlarged view thereof. Referring to fig. 1 and fig. 2 in combination, the probe card of the present embodiment includes a PCB, where the PCB includes a substrate 1 and at least two gold fingers 2 disposed on the upper surface of the substrate 1 and surrounding the center of the substrate 1, in the present embodiment, a circular substrate and 48 gold fingers 2 are taken as an example for illustration, in other embodiments, the substrate 1 may have other shapes, and the number of the gold fingers 2 may be adjusted according to actual needs.

Specifically, in the present embodiment, each gold finger 2 is provided with a test connection point 21, a device connection area 22, a first isolation groove 23, and a second isolation groove 24; the device connection region 22 is positioned in the first isolation groove 23 and disconnected with the golden finger 2 through the first isolation groove 23, and the test connection point 21 is positioned in the second isolation groove 24 and disconnected with the golden finger 2 through the second isolation groove 24; the device connection region 22 is provided with at least two first connection points, in this embodiment, two first connection points are taken as an example, the two first connection points are respectively denoted as 221 and 222, the two first connection points 221 and 222 are electrically connected through metal on the device connection region 22, and at least one of the first connection points is electrically connected with the test connection point 21, the electrical connection manner can be connected through a circuit in the substrate 1, can also be connected through a flying wire, and can also be connected through a conductive path arranged on the lower surface of the substrate 1, where the conductive path arranged on the lower surface of the substrate 1 can be, for example, through arranging gold fingers (not shown in the figure) on the lower surface of the substrate 1, the number of the gold fingers on the lower surface corresponds to the arrangement manner of the gold fingers on the upper surface one by one, the conductive path arranged on the gold fingers on the lower surface, and the gold fingers on the upper and lower surfaces are electrically connected during testing, the electrical connection of each connection point on the gold finger 2 on the upper surface can be realized, which is not specifically limited by the present invention.

In order to measure different electrical parameters simultaneously, a plurality of test connection points 21 may also be provided on each gold finger 2, two test connection points are taken as an example in this embodiment and are respectively marked as 21 and 21'; each test connection point 21, 21 'is individually configured with a corresponding second isolation slot 24, 24' and is disconnected from the gold finger 2 by the corresponding second isolation slot 24, 24 ', and at least one of the two first connection points 221 and 222 is electrically connected to the test connection point 21, 21', respectively.

The upper surface of the substrate 1 is further provided with a plurality of probes 3 and a plurality of probe connection points 4, in this embodiment, the number of channels is 48, that is, the number of the probes 3 is 48, and the number of the probe connection points 4 is 48; the probe 3 is positioned in the center of the upper surface of the substrate 1, the probe connection points 4 are arranged around the periphery of the probe 3, and the 48 golden fingers 2 are arranged in the peripheral area of the probe connection points 4 around the center of the substrate. Each probe 3 is electrically connected to each probe connection point 4, for example, by directly soldering the probe 3 to the probe connection point 4, and each probe connection point 4 is also electrically connected to its corresponding first connection point 221 or 222, and the electrical connection may be made by a circuit in the substrate 1, by flying wire, or by providing a conductive path on the lower surface of the substrate 1. Further, in order to facilitate the communication between the probe pin connection point 4 and the first connection point 221 or 222, the device connection region 22 is disposed at an end of each of the gold fingers 2 near the center of the substrate 1, reducing possible adverse effects due to a long communication path.

When used as a verification board, the probe card can be connected to the first connection points 221 on one device connection area 22 and the first connection points 221 on the other device connection area 22, for example: if the connected components are resistors, the resistors can be used as resistance plates, namely, the two pins of the resistors are respectively connected with the first connecting points 221 on the two different golden fingers 2, the testing machine is used for testing the resistors, the difference between the testing resistance value and the actual component resistance value is compared, if the difference is small, the testing accuracy of the testing machine is higher, the resistors can also be used as standard tests for the delivery of the testing machine in the production process, and the connected components are also capacitors and are used as capacitor plates, and the use method of the capacitors is the same as that of the resistance plates. It should be noted that the components may be connected by two first connection points 222 on different gold fingers 2, or the components may be connected by the first connection point 221 on one gold finger 2 and the first connection point 222 on the other gold finger 2.

When the size of the component is too large, the two gold fingers 2 may not be directly connected, and this embodiment provides a preferred scheme for solving the problem, specifically, a plurality of second connection areas 5 and 5 'are provided on the upper surface of the substrate 1, and the plurality of second connection areas 5 and 5' are located between the gold fingers 2 and the probe connection points 4. The plurality of second connecting areas 5 and 5' are radially arranged outwards to form a plurality of layers by taking the center of the substrate 1 as the center; specifically, in this embodiment, the arrangement is taken as an example of two layers, the second connection region 5 of one layer near the center of the substrate 1 is a metal layer disposed on the upper surface of the substrate 1, the metal layer is, for example, a metal sheet, the metal sheet is provided with through holes 51, which is convenient for pin soldering of the device, the second connection region 5' of the second layer located in the peripheral region is only a metal sheet without through holes, and all the metal sheets are independent from each other and are not conducted with each other. In other embodiments, a user may select whether each second connection area is made of a metal sheet or a through hole is formed in the metal sheet according to actual needs, and the user may also select the number of distribution layers of the second connection areas in order to adapt to components of different sizes.

In order to ensure the uniformity and the aesthetic property of the whole substrate 1, the arrangement of the second connection areas 5 and 5 'in the embodiment is the same as that of the gold fingers 2, and each gold finger 2 is correspondingly provided with two second connection areas 5 and 5' to adapt to components of different sizes.

In order to facilitate the pin soldering of the device and the electrical connection between the first connection point and the test connection point, in this embodiment, in addition to the through hole 51 formed in the second connection region 5 of the layer near the center of the substrate 1, through holes 25 are formed in the first connection points 221 and 222 and the test connection points 21 and 21' on the gold finger 2. When the signal conduction of each connection point on the upper surface of the substrate is realized through the golden finger on the lower surface of the substrate, a through hole is also formed in the golden finger 2 located in the outer area of the first isolation groove 23 and the second isolation grooves 24 and 24 ', and is marked as 25 ', and the through hole 25 ' can realize the electrical connection of the golden fingers on the upper surface and the lower surface of the substrate, so as to realize the simultaneous grounding of the golden fingers on the upper surface and the lower surface. The first connection points 221, 222 may be used as connection points of components during verification, and the through holes 25 on the first connection points 221, 222 and the test connection points 21, 21' may be used to electrically connect the probe connection points, the first connection points and the test connection points during testing.

That is, when the probe card is used as a verification board, the components to be connected may be directly connected between two gold fingers 2 through the first connection points 221 or 222 of the device connection area 22, may be connected between the first connection points 221 or 222 and the second connection area 5 or 5 'on one gold finger 2, may be connected between the first connection points 221 or 222 and the probe connection points 4 on one gold finger 2, may be connected between the probe connection points 4 and the second connection points 5 or 5', and may be connected in series through flying wire connection.

In order to realize the ground protection, the substrate 1 in this embodiment is provided with the ground point 6, and during the test, the ground protection of the substrate 1 can be realized by connecting the ground pressure point of the test head, and the ground protection of the substrate 1 can also be realized by directly connecting the test machine.

In order to reduce the cost, the middle layer of the substrate 1 of the embodiment is made of FR4 material, the upper surface and the lower surface of the substrate 1 are made of ceramic, and the circuit part of the probe card is covered by ceramic. Because the ceramic material is expensive and has small influence on the electric leakage of the probe card, and the FR4 material is very cheap and can generate large electric leakage, the electric leakage of the product is not influenced by adopting the design, and the manufacturing cost is greatly saved.

It should be noted that, in other embodiments, structures that facilitate positioning, installation, taking, or calibrating directions may be added to the substrate 1. For example, in some embodiments, positioning holes 7 may be provided on the substrate 1 for positioning a probe card to fixedly mount the probe card on a probe station; meanwhile, the positioning hole 7 can also be used as a mounting hole of a fixing structure, and the fixing structure such as a bolt is fixed on the probe station, so that the probe card is more firmly mounted, and the pressure point of the test head is more accurate.

In other embodiments, the substrate 1 may further be provided with the easy holding device mounting holes 8 for mounting the easy holding device, the easy holding device mounting holes 8 may be symmetrically or asymmetrically arranged on the substrate 1, the probe card further includes the easy holding device mounted in the easy holding device mounting holes 8, the easy holding device may be mounted and fixed by a single easy holding device mounting hole 8 for a single device, or may be mounted and fixed by a plurality of easy holding device mounting holes 8 when a single device is large, or may be a combination of a plurality of devices, and when a plurality of devices are combined, the plurality of devices are respectively mounted in their corresponding different easy holding device mounting holes 8. In addition, to accommodate user's operating habits or to accommodate environmental considerations such as the use of the probe card, the holding device may be annular, contoured, circular, arcuate, or other irregular shape to accommodate and accommodate the testing environment. The device is convenient to hold, a user can conveniently take and place the device, the problem that the probe card is overhigh in electric leakage due to pollution and damage to the surface of the probe card is avoided, and meanwhile, certain protection effect on parts on the probe card can be achieved.

In other embodiments, the substrate 1 may further be provided with a direction indicator 9, such as an arrow printed on the substrate, which may make it more convenient for a user to determine the direction of the probe, and enable faster positioning and installation.

It should be noted that the substrate 1 in this embodiment is circular, and in other embodiments, the substrate may also be square, rectangular, etc.; in addition, the gold fingers 2, the second connection regions 5 and 5' and the probe connection points 4 in this embodiment are all arranged in a ring shape around the center of the substrate, and in other embodiments, the gold fingers may also be arranged in a square shape, a rectangular shape, an oval shape, and the like, which is not specifically limited in this invention.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the invention, which is defined by the claims and the description of the invention, and all simple equivalent changes and modifications made therein are also within the scope of the invention. Moreover, it is not necessary for any embodiment or claim of the invention to address all of the objects, advantages, or features disclosed herein. In addition, the abstract and the title of the invention are provided for assisting the retrieval of patent documents and are not intended to limit the scope of the invention. Furthermore, the terms "first", "second", and the like in the description or the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used for limiting the upper limit or the lower limit on the number of elements.

Claims (14)

1. A PCB board comprises a substrate and is characterized in that at least two golden fingers are arranged on the upper surface of the substrate around the center of the substrate, each golden finger is provided with a test connection point, a device connection area, a first isolation groove and a second isolation groove, the device connection area is located in the first isolation groove and disconnected with the golden finger through the first isolation groove, and the test connection point is located in the second isolation groove and disconnected with the golden finger through the second isolation groove; the device connection region is provided with at least two first connection points which are electrically connected with each other, and at least one first connection point is electrically connected with the test connection point; the upper surface of the substrate is also provided with a plurality of second connecting areas around the center of the substrate, and the golden fingers are positioned in the peripheral areas of the second connecting areas.

2. The PCB board of claim 1, wherein the device connection region is disposed at an end of each of the gold fingers near a center of the substrate.

3. The PCB board of claim 1, wherein the second connection areas are radially arranged outward in multiple layers centered on the center of the substrate.

4. The PCB board of claim 1 or 3, wherein the second connecting region is a metal layer disposed on the upper surface of the substrate, and each metal layer is not electrically connected to each other.

5. The PCB board of claim 4, wherein the metal layer is provided with a through hole.

6. The PCB board as claimed in claim 1, wherein the second connection region is arranged in the same manner as the gold finger.

7. The PCB board of claim 1, wherein a plurality of test connection points are disposed on each golden finger, each test connection point is individually configured with a corresponding second isolation slot and is disconnected from the golden finger by the corresponding second isolation slot, and at least one first connection point is electrically connected to the plurality of test connection points.

8. The PCB board of claim 1 or 7, wherein the first connection point, the test connection point and the gold finger located at the outer region of the first isolation groove and the second isolation groove are all provided with through holes.

9. The PCB board of claim 8, wherein the lower surface of the substrate is also provided with at least two golden fingers, the golden fingers on the lower surface of the substrate correspond to the golden fingers on the upper surface of the substrate one by one, and the electrical connection between the corresponding golden fingers on the upper surface and the lower surface of the substrate is realized through the through holes on the golden fingers at the outer areas of the first isolation groove and the second isolation groove.

10. The PCB panel of claim 1, wherein a ground point is disposed on the substrate.

11. The PCB board of claim 1, wherein the upper and lower surfaces of the substrate are formed of ceramic material, and the intermediate layer between the upper and lower surfaces is formed of FR4 material.

12. The PCB board of claim 1, wherein the substrate is provided with positioning holes or/and convenient holding device mounting holes; the positioning hole is used for positioning and mounting the PCB, and the convenient holding device mounting hole is used for mounting the convenient holding device.

13. The PCB board of claim 1, wherein the substrate is further provided with a direction indicator.

14. A probe card comprising the PCB of any one of claims 1 to 13, wherein a plurality of probe connection points and a plurality of probes are further disposed on a substrate of the PCB, the plurality of probes are located at a center of an upper surface of the substrate, the plurality of probe connection points are arranged around a periphery of the plurality of probes, the plurality of probes are electrically connected to the plurality of probe connection points, respectively, and the plurality of probe connection points are electrically connected to the plurality of first connection points, respectively.

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