Probe Card Tip Condition Detection Method, Structure, Wafer, and Wafer Testing Method

Abstract

The present application provides a method and structure for detecting the tip condition of a probe card, a wafer, and a wafer testing method. It relates to a method for detecting the tip condition of a probe card, including: determining a plurality of probes to be tested on the probe card; determining a plurality of probe pads, and sequentially arranging a metal wire structure between two probe pads to form a test circuit by connection; respectively inserting the probes to be tested into the corresponding probe pads for contact connection; dividing and designing a plurality of test groups based on the positions of the probe pads in the test circuit, and measuring the contact resistance between the probes to be tested and the corresponding probe pads; and judging the tip state of the probes to be tested based on the contact resistance between the probes to be tested and the corresponding probe pads. The present application monitors the tip condition of the probe card by means of electrical testing, which not only reduces the testing cost, but also further improves the testing accuracy and detection efficiency.

Description

Technical Field

[0001] The present application relates to the field of semiconductor integrated circuit testing, and in particular to a probe card needle tip condition detection method, structure, wafer, and wafer testing method. Background Art

[0002] The probe card is a test interface that connects the chip under test and the tester in wafer testing. It is mainly used for preliminary measurement of the electrical performance of the chip before chip segmentation and packaging. The common needle materials of the probe card are generally composed of metal tungsten and its alloys or copper and its alloys. The probe card needs to be installed on the probe station and cooperate with the movement of the probe station to realize the test of each chip one by one and screen out defective chips.

[0003] During the test process of wafer mass production, each time the probe card is inserted, the needle tip of the probe card will repeatedly come into friction contact with the probe pad on the wafer. The long-term friction process will cause the needle tip to wear and tear. When the needle tip wear accumulates to a certain extent, the contact condition between the needle tip and the probe pad will deteriorate, thus affecting the transmission of electrical signals during the actual test process. However, the equipment required to detect the needle tip condition (needle tip length, needle diameter, flatness) of the probe card is expensive, the detection process is complicated, and the detection cycle is long.

[0004] Therefore, how to accurately monitor and evaluate the condition of the needle tip and repair the probe card in advance before the life of the needle card is reached is very important to the wafer testing process. Summary of the invention

[0005] The present application utilizes electrical testing methods to monitor the needle tip condition of the probe card, which not only reduces the testing cost but also further improves the testing accuracy and detection efficiency.

[0006] To achieve one, part, or all of the above purposes or other purposes, the present invention provides a probe card needle tip condition detection method, structure, wafer, and wafer testing method.

[0007] In a first aspect, the present application provides a method for detecting a probe card tip condition, comprising:

[0008] determining a plurality of probes to be tested of the probe card;

[0009] Determine a plurality of probe pads, and sequentially set a metal wire structure between two of the probe pads to connect and form a test circuit;

[0010] Insert the probes to be tested into corresponding probe pads for contact connection;

[0011] Designing a plurality of test groups based on the positions of the probe pads in the test circuit, and measuring the contact resistance between the probes to be tested and the corresponding probe pads;

[0012] Based on the contact resistance between the probe to be measured and the corresponding probe pad, determine the tip state of the probe to be measured.

[0013] In some of these embodiments, the determining of multiple probe pads and sequentially setting a metal wire structure between two of the probe pads to form a test circuit by connection includes:

[0014] The metal wire structures sequentially set between two of the probe pads are consistent, that is, the resistance values of the metal wire structures sequentially set between two of the probe pads are the same;

[0015] Wherein, the metal wire structure includes metal wires in at least one metal layer;

[0016] The metal wires in the metal layer are at least one of metal wires with straight traces, metal wires with serpentine traces, and metal wires with preset path traces.

[0017] In some of these embodiments, the dividing and designing of multiple test groups based on the positions of the probe pads in the test circuit and measuring the contact resistance between the probe to be measured and the corresponding probe pad includes:

[0018] Taking four adjacent probes to be measured as a first test group, measure the contact resistance between the middle two probes to be measured in the first test group and the corresponding probe pads; by setting at least one first test group, measure the contact resistance between the remaining probes to be measured except the first and last probes to be measured and the corresponding probe pads, and the resistance of the metal wire structure;

[0019] Taking two adjacent probes to be measured as a second test group, based on the resistance of the metal wire structure, measure the contact resistance between the first and last probes to be measured and the corresponding probe pads respectively.

[0020] In some of these embodiments, the taking four adjacent probes to be measured as a first test group and measuring the contact resistance between the middle two probes to be measured in the first test group and the corresponding probe pad includes:

[0021] The four probes to be measured in the first test group are sequentially the first probe to be measured, the second probe to be measured, the third probe to be measured, and the fourth probe to be measured, and the four probe pads corresponding to the four probes to be measured for needle insertion are sequentially the first probe pad, the second probe pad, the third probe pad, and the fourth probe pad;

[0022] Using the second probe to be measured and the third probe to be measured, apply voltages V3 and V4 to the second probe pad and the third probe pad respectively, and measure the current value I1 of the second probe pad or the third probe pad;

[0023] Using the first probe to be measured and the fourth probe to be measured, measure the voltage values V1 and V2 of the first probe pad and the fourth probe pad respectively;

[0024] Based on the voltages V3 and V4, the current value I1, and the voltage values V1 and V2, calculate the contact resistance between the second probe to be measured and the second probe pad, the contact resistance between the third probe to be measured and the third probe pad, and the resistance of the metal wire structure between adjacent probe pads.

[0025] In some embodiments, taking two adjacent probes to be measured as the second test group, and based on the resistance of the metal wire structure, measure the contact resistances between the first and last probes to be measured and the corresponding probe pads respectively, including:

[0026] The two probes to be measured in the second test group are the fifth probe to be measured and the sixth probe to be measured in sequence, and the two probe pads corresponding to the two probes to be measured for needle insertion are the fifth probe pad and the sixth probe pad in sequence; wherein, the fifth probe to be measured is the first probe to be measured or the last probe to be measured;

[0027] Using the fifth probe to be measured and the sixth probe to be measured, apply voltages V5 and V6 on the fifth probe pad and the sixth probe pad respectively, and measure the current value I2 of the fifth probe pad or the sixth probe pad;

[0028] Based on the resistance of the metal wire structure, the contact resistance between the sixth probe to be measured and the sixth probe pad, and the voltages V5 and V6 and the current value I2, calculate the contact resistances between the first and last probes to be measured and the corresponding probe pads.

[0029] In some embodiments, based on the contact resistance between the probe to be measured and the corresponding probe pad, determine the tip state of the probe to be measured, including:

[0030] Obtain a preset tip contact resistance threshold;

[0031] Judge whether the contact resistance between the probe to be measured and the corresponding probe pad is less than the tip contact resistance threshold. If so, the state of the probe to be measured is good; otherwise, the state of the probe to be measured is bad and an alarm is given.

[0032] In some embodiments, insert the probe to be measured into different probe pads multiple times for contact connection to measure multiple contact resistance values between the probe to be measured and the corresponding probe pads;

[0033] Based on the multiple contact resistance values, determine the contact resistance between the probe to be measured and the probe pad, which is used to judge the tip state of the probe to be measured.

[0034] In a second aspect, the present application provides a probe card tip condition test structure for implementing the probe card tip condition detection method described in the first aspect. The probe card tip condition test structure includes a plurality of metal wire structures, a plurality of probe pads, and a plurality of probes to be measured;

[0035] The metal wire structure is sequentially arranged between the two probe pads to form a test circuit;

[0036] The multiple probes to be tested are respectively inserted into the corresponding probe pads to make contact connections with the corresponding probe pads.

[0037] In a third aspect, the present application provides a wafer testing method, which is implemented by using the probe card tip condition testing structure described in the second aspect. The wafer testing method includes the steps of:

[0038] Install a probe card on the probe table to determine the multiple probes to be tested on the probe card;

[0039] Control the wafer to be tested to enter the probe table, and insert the probes to be tested into the corresponding probe pads of the wafer to be tested for contact connection; wherein, the scribing grooves of the wafer to be tested include multiple metal wire structures and multiple probe pads, and the metal wire structures are sequentially arranged between the two probe pads to form a test circuit;

[0040] Based on the positions of the probe pads in the test circuit, design multiple test groups, and measure the contact resistance between the probes to be tested and the corresponding probe pads;

[0041] Based on the contact resistance between the probes to be tested and the corresponding probe pads, judge the tip states of the probes to be tested:

[0042] If the states of all the probes to be tested are good, adjust the position of the wafer to be tested, and use the probe card to insert the needles into the test pads of the wafer to be tested for subsequent wafer testing;

[0043] If there is an alarm situation in the state of the probes to be tested, stop the subsequent wafer testing until all the probes to be tested on the probe card pass the state test.

[0044] In a fourth aspect, the present application provides a wafer for implementing the wafer testing method described in the third aspect. The wafer includes a test circuit and a performance testing structure;

[0045] The test circuit includes multiple metal wire structures and multiple probe pads. The metal wire structures are sequentially arranged between the two probe pads to form a test circuit; the test circuit is placed in the scribing groove of the wafer for testing the tip conditions of the probe card;

[0046] The wafer further includes a performance testing structure for electrically testing the device performance on the wafer.

[0047] Compared with the prior art, the beneficial effects of the present invention mainly include:

[0048] The present application provides a method for detecting the tip condition of a probe card, which monitors the tip condition of the probe card by measuring the contact resistance between the probe under test and the corresponding probe pad, reducing the test cost, further improving the test accuracy and detection efficiency.

[0049] The probe card tip condition test structure of the present application can be used to quickly detect the tip condition of the probe card, which is simple and effective, does not require expensive detection equipment, and can be realized by means of electrical testing.

[0050] The wafer testing method of the present application can first perform a probe card tip condition test before performing a conventional wafer test on the wafer under test. After the tip condition passes the test, subsequent wafer tests are carried out. No additional equipment and steps are required, ensuring the accuracy of subsequent wafer tests.

[0051] The wafer of the present application designs the test circuit and performance test structure for detecting the tip condition of the probe card on the same wafer. By designing the test circuit in the dicing slot of the wafer, it does not affect the placement area of the performance test structure on the chip, and can directly use this wafer to perform the probe card tip condition test before the device performance test, improving the test accuracy and detection efficiency.

[0052] To make the above and other objects, features, and advantages of the present invention more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. Description of the Drawings

[0053] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0054] Figure 1 It is a schematic flow chart of a method for detecting the tip condition of a probe card provided in Embodiment 1 of the present application.

[0055] Figure 2 It is a schematic layout design diagram of the probe pad provided by the present application.

[0056] Figure 3 It is a schematic diagram of contact resistance measurement provided in Embodiment 1 of the present application.

[0057] Figure 4 It is a schematic diagram of the circuit structure of the first test group provided in Embodiment 1 of the present application.

[0058] Figure 5 It is a schematic diagram of the circuit structure of the second test group provided in Embodiment 1 of the present application.

[0059] Figure 6 This is the contact resistance experimental data graph provided for Embodiment 1 of the present application. Specific Embodiments

[0060] Regarding the foregoing and other technical contents, features and effects of the present invention, they will be clearly presented in the following detailed description of a preferred embodiment with reference to the drawings. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or back, etc., are only with reference to the directions of the attached drawings. Therefore, the directional terms used are for illustration and not for limiting the present invention.

[0061] In this application, four adjacent probes to be measured are used as the first test group, and the contact resistance between the middle two probes to be measured and the corresponding probe pads in the first test group is measured by the Kelvin four-terminal method. Two adjacent probes to be measured are used as the second test group, and the contact resistance between the first and last probes to be measured and the corresponding probe pads is measured by the two-terminal method. This application takes the measured contact resistance between the probes to be measured and the corresponding probe pads as an important reference index for whether the tip condition is normal, and further realizes the monitoring of the tip condition of the probe card, which not only reduces the test cost, but also further improves the test accuracy and detection efficiency.

[0062] The following will elaborate on each embodiment of the present application in conjunction with the drawings. However, those of ordinary skill in the art can understand that in each embodiment of the present application, many technical details are provided for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can still be implemented.

[0063] Embodiment 1

[0064] As Figure 1 shown, a method for detecting the tip condition of a probe card includes:

[0065] Step S1: Determine multiple probes to be measured on the probe card;

[0066] Step S2: Determine multiple probe pads, and sequentially set metal wire structures between two probe pads to form a test circuit;

[0067] Step S3: Pierce the probes to be measured into the corresponding probe pads for contact connection respectively;

[0068] Step S4: Divide and design multiple test groups based on the positions of the probe pads in the test circuit, and measure the contact resistance between the probes to be measured and the corresponding probe pads;

[0069] Step S5: Judge the tip state of the probes to be measured based on the contact resistance between the probes to be measured and the corresponding probe pads.

[0070] Specifically, asFigure 2 As shown, the wire structure is sequentially connected between two probe pads. Multiple probe pads and the wire structure sequentially arranged between the two probe pads form a test circuit. The wire structures sequentially arranged between the two probe pads are the same, that is, the resistance values of the wire structures sequentially arranged between the two probe pads are the same. Both ends of any probe pad except the first and last probe pads are connected to the wire. The wire structure includes wires in at least one metal layer. Among them, the wires in the metal layer are at least one of the wires with straight traces, the wires with serpentine traces, and the wires with preset path traces, and the width of the wires should meet the requirements of the chip design rules. The wire connection methods and metal layer combination methods between different probe pads are the same.

[0071] It should be noted that the sequence numbers of steps S1 - S5 are only for convenience of explaining this embodiment and do not involve the limitation of the execution sequence of the steps of this application. For example, in other embodiments, steps S1 and S2 can be executed simultaneously, or step S2 can be executed first and then step S1. This application does not make specific limitations.

[0072] The probe card is installed on the probe stage. The probe card is provided with probes. The wafer is installed on the wafer chuck. The connection between the wafer and the tester is realized by the probes on the probe card piercing the wafer, so as to use the tester to perform wafer testing.

[0073] In this embodiment, by measuring the contact resistance value between the tip of the probe on the probe card and the probe pad, it is used as an important reference index for whether the tip condition is normal, and then the monitoring of the tip condition of the probes on the probe card is realized. As Figure 3 shown, Probing Rc represents the contact resistance between the probe to be measured and the corresponding probe pad, and Metal Rs represents the resistance value of the wire structure connecting two adjacent probe pads.

[0074] In this embodiment, multiple test groups are designed based on the positions of the probe pads in the test circuit, and the contact resistance between the probe to be measured and the corresponding probe pad is measured, including: taking four adjacent probes to be measured as the first test group, and measuring the contact resistance between the middle two probes to be measured in the first test group and the corresponding probe pads by the Kelvin four-terminal method. By setting at least one first test group, the contact resistance between the remaining probes to be measured except the first and last probes to be measured and the corresponding probe pads, and the resistance of the wire structure are measured. Then, taking two adjacent probes to be measured as the second test group, based on the resistance of the wire structure, the contact resistance between the first and last probes to be measured and the corresponding probe pads is measured by the two-terminal method. By setting two second test groups, the contact resistance between the first and last probes to be measured and the corresponding probe pads is measured respectively.

[0075] Specifically, first, as Figure 4As shown, in this embodiment, four adjacent probes to be measured form a first test group, and the contact resistances between the middle two probes to be measured in the first test group and the corresponding probe pads are measured. Specifically, it includes:

[0076] Any four adjacent probe pads form a first test group. The four probes to be measured in the first test group are successively the first probe to be measured, the second probe to be measured, the third probe to be measured, and the fourth probe to be measured. The four probe pads corresponding to the four probes to be measured for needle insertion are successively the first probe pad (Pad1), the second probe pad (Pad2), the third probe pad (Pad3), and the fourth probe pad (Pad4);

[0077] Using the second probe to be measured and the third probe to be measured, voltages V3 and V4 are respectively applied to the second probe pad and the third probe pad, that is, a voltage difference Vf1 is applied to the second probe pad and the third probe pad, and the current value I1 of the second probe pad or the third probe pad is measured;

[0078] Using the first probe to be measured and the fourth probe to be measured, the voltage values V1 and V2 of the first probe pad and the fourth probe pad are respectively measured;

[0079] Based on the voltages V3 and V4, the current value I1, and the voltage values V1 and V2, the contact resistances between the second probe to be measured and the second probe pad, between the third probe to be measured and the third probe pad, and the resistance of the metal wire structure between adjacent probe pads are calculated. The specific calculation methods include:

[0080] 1) The contact resistance Rc2 between the second probe to be measured and the second probe pad = (V3 - V1) / I1;

[0081] Since the first probe pad (Pad1) and the second probe pad (Pad2) are conducting, the voltage on Pad2 can be measured on Pad1, and the large impedance mode is used for measuring resistance. Therefore, it is considered that (V3 - V1) is the voltage drop of Rc2; in addition, it is considered that the current values measured at the second probe pad or the third probe pad are the same. Therefore, only one place can be measured and recorded as the current value I1;

[0082] 2) The contact resistance Rc3 between the third probe to be measured and the third probe pad = (V4 - V2) / I1;

[0083] Since the third probe pad (Pad3) and the fourth probe pad (Pad4) are conducting, the voltage on Pad3 can be measured on Pad4, and the large impedance mode is used for measuring resistance. Therefore, it is considered that (V4 - V2) is the voltage drop of Rc3; in addition, it is considered that the current values measured at the second probe pad or the third probe pad are the same. Therefore, only one place can be measured and recorded as the current value I1, and the same is true for the current flowing through the metal wire structure subsequently;

[0084] 3) Resistance of the metal wire structure between adjacent probe pads (Pad2 and Pad3) Rs = (V1-V2) / I1;

[0085] The voltage value V1 is the voltage on the second probe pad (Pad2), and the voltage value V2 is the voltage on the third probe pad (Pad3). The reason is the same as above and will not be repeated here. Therefore, it is considered that (V1-V2) is the voltage drop of Rc3. In this embodiment, the resistance value of all metal wire structures arranged between the two probe pads is the same, which is Rs.

[0086] In this embodiment, at least one first test group is set to measure the contact resistance between the remaining probes to be tested and the corresponding probe pads, as well as the resistance of the metal wire structure, except for the first and last two probes to be tested. Assuming that there are 25 probes to be tested and 25 corresponding probe pads, the same method can be used to measure Rc2 and Rc3 (the first first test group), Rc4 and Rc5 (the second first test group), ..., Rc23 and Rc24 (the twelfth first test group); that is, the tip contact resistance Rc except for the first two pads is tested.

[0087] This embodiment reasonably plans and arranges at least one first test group to measure the contact resistance between the probes to be tested (except the first and last probes) and the corresponding probe pads using the Kelvin four-terminal method. The design is reasonable, ingenious and effective.

[0088] Then, if Figure 5 As shown, in this embodiment, two adjacent probes to be tested are used as the second test group, and based on the resistance of the metal wire structure, the contact resistances between the first and last two probes to be tested and the corresponding probe pads are measured respectively, including:

[0089] The two probes to be tested in the second test group are the fifth probe to be tested and the sixth probe to be tested, respectively. The two probe pads corresponding to the two probes to be tested are the fifth probe pad (Pad1 or Pad25) and the sixth probe pad (Pad2 or Pad24), respectively. The fifth probe to be tested is the first probe to be tested or the last probe to be tested.

[0090] Using the fifth probe to be tested and the sixth probe to be tested, voltages V5 and V6 are applied to the fifth probe pad and the sixth probe pad, respectively, that is, a voltage difference Vf2 is applied to the fifth probe pad and the sixth probe pad, and a current value I2 of the fifth probe pad or the sixth probe pad is measured;

[0091] Based on the resistance of the metal wire structure, the contact resistance between the sixth probe to be tested and the sixth probe pad, as well as the voltages V5, V6 and the current value I2, the contact resistances between the first and last two probes to be tested and the corresponding probe pads are calculated; the following is an example of the fifth probe to be tested as the first probe to be tested. The specific process is as follows Figure 5 As shown, including:

[0092] The contact resistance Rc1 between the first probe to be measured and the fifth probe pad (Pad1) = (V5 - V6) / I2 - Rs - Rc2;

[0093] (V5 - V6) is Vf2. Since the resistances in this circuit loop include the contact resistance Rc1 between the first probe to be measured and Pad1, the contact resistance Rc2 obtained through the foregoing process, and the metal wire structure resistance Rs (in this embodiment, the resistances of all metal wire structures arranged between two probe pads are the same, all being Rs); in addition, it is considered that the current values measured at the fifth probe pad and the sixth probe pad are the same, so the current can be measured at only one place and recorded as the current value I2.

[0094] As Figure 5 shown, similarly, the contact resistance Rc25 between the last probe to be measured and the corresponding probe pad can be measured as Rc25 = (V5 - V6) / I2 - Rs - Rc24.

[0095] In this embodiment, based on the contact resistance between the probe to be measured and the corresponding probe pad, the tip state of the probe to be measured is judged, including: obtaining a preset tip contact resistance threshold; judging whether the contact resistance between the probe to be measured and the corresponding probe pad is less than the tip contact resistance threshold. If so, the state of the probe to be measured is good; otherwise, the state of the probe to be measured is bad and an alarm is given. In the application scenario of this embodiment, as Figure 6 shown, the preset threshold is 10 ohms, and reference can be made to Figure 6 the straight line y = 10 representing this threshold (Rc_Spec); the contact resistance value is compared with the preset threshold. If the contact resistance value is less than 10 ohms, the tip state is normal; if it is greater than 10 ohms, the tip state is abnormal and an alarm is given.

[0096] Figure 6 It is a data graph of the contact resistance (Rc) between a 25-pin probe to be measured and the corresponding probe pad (pad). The abscissa represents 23 of the probes to be measured, and the ordinate represents the corresponding contact resistance values; as Figure 6 shown, in this embodiment, the Rc of the tips of all probes is less than Rc_Spec (10 ohms), indicating that the state of the probes to be measured is good, that is, the conditions of all the needle cards are normal.

[0097] It should be noted that Figure 6 the contact resistances of different colors in

[0098] In this embodiment, the probe to be measured is repeatedly pricked into different probe pads for contact connection to measure the contact resistance values between multiple probes to be measured and the corresponding probe pads. Based on the multiple contact resistance values, the contact resistance between the probe to be measured and the probe pad is determined to judge the tip state of the probe to be measured. A specific example is as follows Figure 6 As shown, each contact resistance is basically not a point value, but a drawn interval value, that is, it means that each probe to be measured is repeatedly pricked into different probe pads for contact connection to measure multiple contact resistance values. Figure 6 The median of these multiple contact resistance values is also calculated. By repeatedly pricking each probe to be measured into different probe pads to calculate the contact resistance, accidental errors that may cause data anomalies are avoided, and the reliability of monitoring the tip condition of the probe card is improved.

[0099] Embodiment 2

[0100] This embodiment provides a test structure for the tip condition of a probe card, which is used to implement the method for detecting the tip condition of the probe card in Embodiment 1. The test structure for the tip condition of the probe card includes: a plurality of metal wire structures, a plurality of probe pads, and a plurality of probes to be measured; the metal wire structures are sequentially arranged between two probe pads to form a test circuit. The test circuit can be referred to Figure 2 ; a plurality of probes to be measured are respectively pricked into the corresponding probe pads and are in contact connection with the corresponding probe pads.

[0101] In this embodiment, to determine a plurality of probe pads and sequentially arrange metal wire structures between two probe pads to form a test circuit, it includes: the metal wire structures sequentially arranged between two probe pads are the same, that is, the resistance values of the metal wire structures sequentially arranged between two probe pads are the same; wherein, the metal wire structure includes metal wires in at least one metal layer; the metal wires in the metal layer are at least one of straight-walking metal wires, serpentine-walking metal wires, and metal wires with a preset path.

[0102] In summary, the method for detecting the tip condition of the probe card and the test structure for the tip condition of the probe card of the present application realize the monitoring of the tip condition of the probe card by means of electrical testing, which not only reduces the test cost, but also improves the test accuracy and detection efficiency.

[0103] Embodiment 3

[0104] This embodiment provides a wafer testing method, which is implemented by using the probe tip condition testing structure in Embodiment 2. The wafer testing method includes the steps of: installing a probe card on a probe table and determining a plurality of probes to be tested on the probe card; controlling the wafer to be tested to enter the probe table and respectively inserting the probes to be tested into the corresponding probe pads of the wafer to be tested for contact connection; wherein, the scribing grooves of the wafer to be tested include a plurality of metal wire structures and a plurality of probe pads, and the metal wire structures are sequentially arranged between two probe pads to form a test circuit; designing a plurality of test groups based on the positions of the probe pads in the test circuit, and measuring the contact resistance between the probes to be tested and the corresponding probe pads; based on the contact resistance between the probes to be tested and the corresponding probe pads, determining the tip states of the probes to be tested: if the states of all the probes to be tested are good, adjusting the position of the wafer to be tested, and using the probe card to insert the probes into the test pads of the wafer to be tested for subsequent wafer testing; if there is an alarm situation for the state of a probe to be tested, stopping the subsequent wafer testing until all the probes to be tested on the probe card pass the state test.

[0105] In this embodiment, the metal wire structures sequentially arranged between two probe pads are consistent, that is, the resistance values of the metal wire structures sequentially arranged between two probe pads are the same; wherein, the metal wire structure includes metal wires in at least one metal layer; the metal wires in the metal layer are at least one of metal wires with straight traces, metal wires with serpentine traces, and metal wires with preset path traces.

[0106] In this embodiment, designing a plurality of test groups based on the positions of the probe pads in the test circuit and measuring the contact resistance between the probes to be tested and the corresponding probe pads includes:

[0107] 1) Taking four adjacent probes to be tested as a first test group, and measuring the contact resistance between the middle two probes to be tested in the first test group and the corresponding probe pads by the Kelvin four-terminal method; by setting at least one first test group, measuring the contact resistance between the probes to be tested except the first and last probes to be tested and the corresponding probe pads, and the resistance of the metal wire structure. Specifically: the four probes to be tested in the first test group are the first probe to be tested, the second probe to be tested, the third probe to be tested, and the fourth probe to be tested in sequence, and the four probe pads corresponding to the four probes to be tested are inserted with needles are the first probe pad, the second probe pad, the third probe pad, and the fourth probe pad in sequence; using the second probe to be tested and the third probe to be tested, applying voltages V3 and V4 on the second probe pad and the third probe pad respectively, and measuring the current value I1 of the second probe pad or the third probe pad; using the first probe to be tested and the fourth probe to be tested, measuring the voltage values V1 and V2 of the first probe pad and the fourth probe pad respectively; based on the voltages V3 and V4, the current value I1, and the voltage values V1 and V2, calculating the contact resistance between the second probe to be tested and the second probe pad, the contact resistance between the third probe to be tested and the third probe pad, and the resistance of the metal wire structure between adjacent probe pads.

[0108] 2) Take two adjacent probes to be tested as the second test group. Based on the resistance of the metal wire structure, measure the contact resistances between the first and the last probes to be tested and their corresponding probe pads respectively by the two-terminal method. Specifically: The two probes to be tested in the second test group are the fifth probe to be tested and the sixth probe to be tested in sequence, and the two probe pads corresponding to the two probes to be tested for needle insertion are the fifth probe pad and the sixth probe pad in sequence; among them, the fifth probe to be tested is the first probe to be tested or the last probe to be tested; use the fifth probe to be tested and the sixth probe to be tested to apply voltages V5 and V6 on the fifth probe pad and the sixth probe pad respectively, and measure the current value I2 of the fifth probe pad or the sixth probe pad; based on the resistance of the metal wire structure, the contact resistance between the sixth probe to be tested and the sixth probe pad, as well as the voltages V5, V6 and the current value I2, calculate the contact resistances between the first and the last probes to be tested and their corresponding probe pads.

[0109] In this embodiment, based on the contact resistance between the probe to be tested and the corresponding probe pad, judge the tip state of the probe to be tested, including: obtaining a preset tip contact resistance threshold; judging whether the contact resistance between the probe to be tested and the corresponding probe pad is less than the tip contact resistance threshold, if so, the state of this probe to be tested is good, otherwise, the state of this probe to be tested is bad and an alarm is given.

[0110] In this embodiment, insert the probe to be tested into different probe pads multiple times for contact connection to measure the contact resistance values between multiple probes to be tested and their corresponding probe pads; based on the multiple contact resistance values, determine the contact resistance between the probe to be tested and the probe pad, which is used to judge the tip state of the probe to be tested.

[0111] In this embodiment, a wafer is also provided for implementing the wafer test method in this embodiment. The wafer includes a test circuit and a performance test structure; the test circuit includes a plurality of metal wire structures and a plurality of probe pads, and the metal wire structures are arranged between two probe pads in sequence to form a test circuit; the test circuit is placed in the dicing slot of the wafer for testing the tip condition of the probe card; the wafer also includes a performance test structure, and the performance test structure is used for electrically testing the device performance on the wafer.

[0112] In summary, based on the probe card tip condition test structure, this application proposes an optimized wafer test method, which realizes that before performing a conventional wafer test on the wafer to be tested, the tip condition of the probe card can be tested first. After the tip state passes the test, subsequent wafer tests are carried out. No additional equipment and steps are required, ensuring the accuracy of subsequent wafer tests. Further, this application also provides a wafer for the foregoing wafer test method. By designing the test circuit in the dicing slot of the wafer, it does not affect the placement area of the performance test structure on the chip, and can directly use this wafer to test the tip state of the probe card before device performance testing, improving the test accuracy and detection efficiency.

[0113] Some common English nouns or letters used in this invention for the sake of clear description are only for exemplary reference rather than restrictive interpretation or specific usage, and the protection scope of this invention should not be limited by their possible Chinese translations or specific letters.

[0114] It should also be noted that in this text, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

Claims

1. A method for detecting the tip condition of a probe card, characterized in that, Including: Determine multiple probes to be tested on the probe card; Determine multiple probe pads, and sequentially set wire structures between two of the probe pads to connect and form a test circuit; Pierce the probes to be tested into the corresponding probe pads respectively for contact connection; Based on the positions of the probe pads in the test circuit, divide and design multiple test groups, and measure the contact resistance between the probes to be tested and the corresponding probe pads, including: Take four adjacent probes to be tested as the first test group, and measure the contact resistance between the middle two probes to be tested in the first test group and the corresponding probe pads by the Kelvin four-terminal method; by setting at least one first test group, measure the contact resistance between the remaining probes to be tested except the first and last probes to be tested and the corresponding probe pads, and the resistance of the wire structure; Take two adjacent probes to be tested as the second test group, and based on the resistance of the wire structure, measure the contact resistance between the first and last probes to be tested and the corresponding probe pads respectively by the two-terminal method; Based on the contact resistance between the probes to be tested and the corresponding probe pads, judge the tip state of the probes to be tested.

2. The method for detecting the tip condition of a probe card according to claim 1, wherein The determining multiple probe pads and sequentially setting wire structures between two of the probe pads to connect and form a test circuit includes: The wire structures sequentially arranged between two of the probe pads are consistent, that is, the resistance values of the wire structures sequentially arranged between two of the probe pads are the same; Wherein, the wire structure includes wires in at least one metal layer; The wires in the metal layer are at least one of straight-wired wires, serpentine-wired wires, and wires with a preset path; 3. The method for detecting the tip condition of a probe card according to claim 1, wherein The taking four adjacent probes to be tested as the first test group and measuring the contact resistance between the middle two probes to be tested in the first test group and the corresponding probe pads includes: The four probes to be tested in the first test group are sequentially the first probe to be tested, the second probe to be tested, the third probe to be tested, and the fourth probe to be tested, and the four probe pads corresponding to the four probes to be tested are sequentially the first probe pad, the second probe pad, the third probe pad, and the fourth probe pad; Use the second probe to be tested and the third probe to be tested to apply voltages V3 and V4 to the second probe pad and the third probe pad respectively, and measure the current value I1 of the second probe pad or the third probe pad; Use the first probe to be tested and the fourth probe to be tested to measure the voltage values V1 and V2 of the first probe pad and the fourth probe pad respectively; Based on the voltages V3 and V4, the current value I1, and the voltage values V1 and V2, calculate the contact resistance between the second probe to be tested and the second probe pad, the contact resistance between the third probe to be tested and the third probe pad, and the resistance of the wire structure between adjacent probe pads.

4. The method for detecting the tip condition of a probe card according to claim 3, characterized in that, The taking two adjacent probes to be tested as the second test group and measuring the contact resistance between the first and last probes to be tested and the corresponding probe pads respectively based on the resistance of the wire structure includes: The two probes to be tested in the second test group are sequentially the fifth probe to be tested and the sixth probe to be tested, and the two probe pads corresponding to the two probes to be tested are sequentially the fifth probe pad and the sixth probe pad; wherein, the fifth probe to be tested is the first or last probe to be tested; Apply voltages V5 and V6 to the fifth probe pad and the sixth probe pad respectively by using the fifth probe under test and the sixth probe under test, and measure the current value I2 of the fifth probe pad or the sixth probe pad; Based on the resistance of the metal wire structure, the contact resistance between the sixth probe under test and the sixth probe pad, and the voltages V5, V6 and the current value I2, calculate the contact resistances between the first and the last probes under test and the corresponding probe pads.

5. The method for detecting the condition of the probe card tip according to claim 4, wherein, Based on the contact resistances between the probes under test and the corresponding probe pads, judge the tip states of the probes under test, including: Obtain a preset tip contact resistance threshold; Judge whether the contact resistance between the probe under test and the corresponding probe pad is less than the tip contact resistance threshold. If so, the state of the probe under test is good; otherwise, the state of the probe under test is bad and an alarm is given.

6. The method for detecting the tip condition of a probe card according to claim 1, wherein Pierce the probe under test into different probe pads multiple times for contact connection to measure multiple contact resistance values between the probe under test and the corresponding probe pads; Based on the multiple contact resistance values, determine the contact resistance between the probe under test and the probe pad for judging the tip state of the probe under test.

7. A probe card tip condition testing structure for implementing the probe card tip condition detection method according to any one of claims 1 to 6, characterized in that, The probe card tip condition test structure includes a plurality of metal wire structures, a plurality of probe pads and a plurality of probes under test; The metal wire structures are sequentially arranged between the two probe pads to form a test circuit; The plurality of probes under test are respectively pierced into the corresponding probe pads to make contact connections with the corresponding probe pads.

8. A wafer testing method implemented by using the probe card tip condition testing structure according to claim 7, characterized in that, The wafer testing method includes the steps: Install a probe card on the probe station and determine the plurality of probes under test of the probe card; Control the wafer under test to enter the probe station, and pierce the probes under test into the corresponding probe pads of the wafer under test for contact connection; wherein, the scribing grooves of the wafer under test include a plurality of metal wire structures and a plurality of probe pads, and the metal wire structures are sequentially arranged between the two probe pads to form a test circuit; Based on the positions of the probe pads in the test circuit, design a plurality of test groups and measure the contact resistances between the probes under test and the corresponding probe pads; Based on the contact resistances between the probes under test and the corresponding probe pads, judge the tip states of the probes under test: If the states of all the probes under test are good, adjust the position of the wafer under test, and use the probe card to pierce into the test pads of the wafer under test for subsequent wafer testing; If there is an alarm situation for the state of the probe under test, stop the subsequent wafer testing until all the probes under test on the probe card pass the state test.

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