Resistance measuring device and measuring method for high resistance metal interconnection structure

Abstract

The application provides a resistance measuring device and method for a large-resistance metal interconnection structure. The application adds an introduction branch and controls the input signal of a corresponding pad, so that the introduction resistances on the introduction branch respectively form parallel circuits with the large-resistance metal interconnection structure, and then the parallel resistance of the parallel circuits is obtained according to the corresponding measurement results, so as to obtain the resistance of the large-resistance metal interconnection structure. The resistance of the super-large resistance can be accurately measured, and the resistance of the introduction resistance can be accurately measured.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and in particular to a resistance measuring device and method for a high-resistivity metal interconnect structure in an integrated circuit chip. Background Technology

[0002] Stress migration testing is an important test for evaluating the reliability of metal interconnect structures in integrated circuit chips. This test involves baking the integrated circuit chip at a certain high temperature for a specific time and assessing whether the deviation of the resistance of the relevant structure after baking from the initial resistance is within an acceptable range.

[0003] Due to limitations in the accuracy and range of measuring equipment, it is usually impossible to accurately measure the resistance of some high-resistance metal interconnect structures in integrated circuit chips. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a resistance measuring device and method for a high-resistivity metal interconnect structure, which can accurately measure the resistance of the high-resistivity metal interconnect structure.

[0005] To address the aforementioned problems, this invention provides a resistance measurement device for a high-resistance metal interconnect structure, wherein the high-resistance metal interconnect structure has opposing first and second ends; the device includes: a first inlet branch electrically connected between the first end and a common node of the branch, the first inlet branch including at least one first inlet resistor; a second inlet branch electrically connected between the second end and the common node of the branch, the second inlet branch including at least one second inlet resistor; a test pad set, the test pad set including a first pad electrically connected to the common node of the branch, a second pad electrically connected to the first end, and a third pad electrically connected to the second end; and a measurement module, configured to provide a first constant current or apply a first voltage to the first pad, apply a common voltage to the second pad and the third pad, and acquire a first measured voltage or a first measured current on the first pad; and to provide a second constant current or apply a second voltage to the second pad, and to acquire a first measured voltage or a first measured current on the first pad; and to acquire a first measured voltage or a first measured current on the second pad, and to acquire a first measured voltage or a first measured current on the first pad; and to acquire a first measured voltage or a first measured current on the second pad, and to acquire a second measured current on the first pad. The common voltage is applied to the first pad and the third pad, and a second measured voltage or a second measured current is collected on the second pad; and it is used to provide a third constant current or apply a third voltage to the third pad, apply the common voltage to the first pad and the second pad, and collect a third measured voltage or a third measured current on the third pad, wherein the first voltage, the second voltage, and the third voltage are all greater than the common voltage; the processing module is used to obtain a first parallel resistance value of the first input branch and the second input branch in parallel according to the first measured voltage or the first measured current, obtain a second parallel resistance value of the first input branch and the large-resistance metal interconnect structure in parallel according to the second measured voltage or the second measured current, obtain a third parallel resistance value of the second input branch and the large-resistance metal interconnect structure in parallel according to the third measured voltage or the third measured current, and obtain the resistance value of the large-resistance metal interconnect structure according to the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value.

[0006] To address the aforementioned problems, the present invention also provides a method for measuring the resistance of a high-resistance metal interconnect structure, wherein the high-resistance metal interconnect structure has a first end and a second end opposite to each other; the method includes the following steps: providing a resistance measuring device for a high-resistance metal interconnect structure, wherein a first input branch of the device is electrically connected between the first end and a common node of the branch, a second input branch of the device is electrically connected between the second end and the common node of the branch, a first pad in a test pad group of the device is electrically connected to the common node of the branch, a second pad in the test pad group is electrically connected to the first end, and a third pad in the test pad group is electrically connected to the second end, wherein the first input branch includes at least one first input resistor, and the second input branch includes at least one second input resistor; providing a first constant current or applying a first voltage to the first pad, applying a common voltage to the second pad and the third pad, and acquiring a first measured voltage or a first measured voltage on the first pad. The system measures current; provides a second constant current or applies a second voltage to the second pad, applies the common voltage to the first pad and the third pad, and acquires a second measured voltage or a second measured current on the second pad; provides a third constant current or applies a third voltage to the third pad, applies the common voltage to the first pad and the second pad, and acquires a third measured voltage or a third measured current on the third pad; obtains a first parallel resistance value of the first input branch and the second input branch connected in parallel based on a first measured voltage or a first measured current, obtains a second parallel resistance value of the first input branch and the large-resistance metal interconnect structure connected in parallel based on a second measured voltage or a second measured current, obtains a third parallel resistance value of the second input branch and the large-resistance metal interconnect structure connected in parallel based on a third measured voltage or a third measured current, and obtains the resistance value of the large-resistance metal interconnect structure based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value.

[0007] The above technical solution, by adding an input branch and controlling the input signal of the corresponding pad, allows the input resistors on the input branch to form parallel circuits with the large-resistance metal interconnect structure. The parallel resistance value of the parallel circuit is then obtained based on the measurement results, thereby obtaining the resistance value of the large-resistance metal interconnect structure. This enables accurate measurement of ultra-large resistance values ​​and accurate measurement of the input resistor value. Furthermore, the input resistor on the input branch can be a single resistor or multiple resistors connected in series; and the resistor material and thickness are not limited, improving the flexibility of the resistance measurement device and facilitating its widespread application. Further control of the input resistor to a smaller value improves measurement accuracy, reduces the influence of the input resistor on the large-resistance metal interconnect structure under test, and lowers the manufacturing cost of the input resistor.

[0008] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 A schematic diagram of the architecture of a resistance measurement device with a large-resistance metal interconnect structure provided in an embodiment of the present invention;

[0011] Figure 2 for Figure 1 The diagram shows the principle of the device for obtaining parallel resistance.

[0012] Figure 3 A schematic diagram of the architecture of a resistance measurement device with a large-resistance metal interconnect structure provided in another embodiment of the present invention;

[0013] Figure 4 for Figure 3 The diagram shows the principle of the device for obtaining parallel resistance.

[0014] Figure 5 This is a flowchart illustrating a method for measuring the resistance of a high-resistance metal interconnect structure according to an embodiment of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please refer to the following: Figures 1-2 ,in, Figure 1 This is a schematic diagram of the architecture of a resistance measurement device with a large-resistance metal interconnect structure provided in an embodiment of the present invention. Figure 2 for Figure 1 The diagram shows the principle of the device for obtaining parallel resistance values. The arrows in the diagram indicate one direction of current flow during measurement.

[0017] like Figure 1As shown, the high-resistance metal interconnect structure 10 serves as the resistor under test Rtest, having a corresponding first terminal 10A (corresponding to...). Figure 2 Point a) and the second end 10B (corresponding to) Figure 2 (Point b shown). The resistance measuring device includes: a first input branch 11, a second input branch 12, a test pad group 13, a measuring module 14, and a processing module 15.

[0018] Specifically, the first inlet branch 11 is electrically connected to the first terminal 10A and a branch common node 10C (corresponding to...). Figure 2 Between point c shown, the first input branch 11 includes a first input resistor R1. The second input branch 12 is electrically connected between the second terminal 10B and the common node 10C of the branches, and the second input branch 12 includes a second input resistor R2.

[0019] In some embodiments, the first input branch 11 may also include multiple first input resistors R1 connected in series, and / or the second input branch 12 may also include multiple second input resistors R2 connected in series. The input resistors in the same branch may be the same or different, and the input resistors in different branches may be the same or different, so as to improve the flexibility of the resistance measuring device of the present invention and facilitate its promotion.

[0020] In some embodiments, the total resistance of the first inlet branch 11 and the total resistance of the second inlet branch 12 are both less than the resistance of the large-resistance metal interconnect structure 10. That is, a resistor with a smaller resistance is introduced to measure the resistance of the resistor under test, thereby improving measurement accuracy, reducing the influence of the introduced resistor on the resistor under test, and reducing the manufacturing cost of the introduced resistor.

[0021] In some embodiments, the first introducing resistor R1, the second introducing resistor R2, and the large-resistance metal interconnect structure 10 are manufactured using the same process, thereby improving measurement accuracy, reducing the influence of the introducing resistor on the resistor under test, and simplifying the fabrication process of the introducing resistor. In other embodiments, the resistive material, thickness, etc., of the introducing resistor can also be unrestricted, thereby improving the flexibility of the resistance measurement device of the present invention and facilitating its widespread adoption.

[0022] Specifically, the test pad group 13 includes a first pad 131 electrically connected to the branch common node 10C, a second pad 132 electrically connected to the first end 10A, and a third pad 133 electrically connected to the second end 10B.

[0023] Specifically, the measurement module 14 is used to provide a first constant current I1 or apply a first voltage V1 to the first pad 131, apply a common voltage V0 to the second pad 132 and the third pad 133, and acquire a first measurement voltage Vtest1 or a first measurement current Itest1 on the first pad 131. The measurement module 14 is also used to provide a second constant current I2 or apply a second voltage V2 to the second pad 132, apply the common voltage V0 to the first pad 131 and the third pad 133, and acquire a second measurement voltage Vtest2 or a second measurement current Itest2 on the second pad 132. The measurement module 14 is also used to provide a third constant current I3 or apply a third voltage V3 to the third pad 133, apply the common voltage V0 to the first pad 131 and the second pad 132, and acquire a third measurement voltage Vtest3 or a third measurement current Itest3 on the third pad 133. Wherein, the first voltage V1, the second voltage V2, and the third voltage V3 are all greater than the common voltage V0. It should be noted that the measurement module 14 provides constant current or applies voltage to the first pad 131, the second pad 132 and the third pad 133 in a time-division manner, but the order is not restricted.

[0024] In some embodiments, the current values ​​of the first constant current I1, the second constant current I2, and the third constant current I3 are the same; that is, the measurement module 14 times provides the same constant current to the first pad 131, the second pad 132, and the third pad 133.

[0025] In some embodiments, the voltage values ​​of the first voltage V1, the second voltage V2, and the third voltage V3 are the same; that is, the measurement module 14 times applies the same voltage to the first pad 131, the second pad 132, and the third pad 133.

[0026] In some embodiments, the measurement module 14 may employ a source measurement unit (SMU) to provide a voltage source with a measurement resolution of less than 1 mV or a current source with a measurement resolution of less than 1 uA. A source measurement unit is a precision power supply device that can provide not only a voltage source with a measurement resolution of less than 1 mV but also a current source with a measurement resolution of less than 1 uA. The source measurement unit can improve production efficiency, perform more comprehensive characteristic tests, and enhance the overall performance of the test system.

[0027] Specifically, the processing module 15 is used to obtain the first parallel resistance value Rc of the first input branch 11 and the second input branch 12 in parallel according to the first measurement voltage Vtest1 or the first measurement current Itest1; to obtain the second parallel resistance value Ra of the first input branch 11 and the large-resistance metal interconnect structure 10 in parallel according to the second measurement voltage Vtest2 or the second measurement current Itest2; to obtain the third parallel resistance value Rb of the second input branch 12 and the large-resistance metal interconnect structure 10 in parallel according to the third measurement voltage Vtest3 or the third measurement current Itest3; and to obtain the resistance value of the large-resistance metal interconnect structure 12 (i.e., the resistor under test Rtest) according to the first parallel resistance value Rc, the second parallel resistance value Ra, and the third parallel resistance value Rb.

[0028] In some embodiments, the processing module 15 may employ a microprocessor.

[0029] In some embodiments, the first parallel resistance value Rc, the second parallel resistance value Ra, and the third parallel resistance value Rb are obtained by the following formulas:

[0030] Rc=(Vc-V0) / Ic, Ra=(Va-V0) / Ia, Rb=(Vb-V0) / Ib;

[0031] Wherein, V0 is the common voltage; Vc is the first measuring voltage and Ic is the first constant current, or Vc is the first voltage and Ic is the first measuring current; Va is the second measuring voltage and Ia is the second constant current, or Va is the second voltage and Ia is the second measuring current; Vb is the third measuring voltage and Ib is the third constant current, or Vb is the third voltage and Ib is the third measuring current. Figure 1 In the diagram, when A in the circle represents a current source, V in the circle represents a voltmeter. In this case, each pad can be measured with a voltmeter to obtain the corresponding voltage measurement value, thereby improving the measurement accuracy. When A in the circle represents an ammeter, V in the circle represents a voltage source, and each pad is subjected to the corresponding voltage as needed.

[0032] In some embodiments, the resistance value of the high-resistance metal interconnect structure 11 is obtained by the following formula:

[0033] 2 / Rtest = 1 / Ra + 1 / Rb - 1 / Rc;

[0034] Wherein, Rtest is the resistance value of the large-resistance metal interconnect structure, Rc is the first parallel resistance value, Ra is the second parallel resistance value, and Rb is the third parallel resistance value.

[0035] The following combination Figure 2Taking the second voltage V0 = 0 as an example, where the measurement module 14 times provides a corresponding constant current to the first pad 131, the second pad 132, and the third pad 133, the principle of measuring the resistance value of the large-resistance metal interconnect structure 11 (i.e., the resistor under test Rtest) is explained. The measurement method of providing a constant current to the corresponding pads and obtaining the corresponding measurement voltage can obtain more accurate measurement results and avoid the influence of voltage drop on the measurement results.

[0036] (1) Ground point a through the second pad 132 (or connect to 0V), ground point b through the third pad 133 (or connect to 0V), and input the first constant current I1 through the first pad 131 at point c; that is, the resistor R1 on the first input branch 11 is connected in parallel with the resistor R2 on the second input branch 12; by measuring the first measurement voltage Vc at point c, the first parallel resistance value Rc=(Vc-V0) / I1 is calculated.

[0037] (2) Ground point b through the third pad 133 (or connect to 0V), ground point c through the first pad 131 (or connect to 0V), and input the second constant current I3 into the second pad 132 at point a; that is, the large resistance metal interconnect structure 10, which is the resistor R1 on the first input branch 11, is connected in parallel with the resistor R1 of the resistor Rtest to be measured; by measuring the second measurement voltage Va at point a, the second parallel resistance value Ra=(Va-V0) / I2 is calculated.

[0038] (3) Ground point a through the second pad 132 (or connect to 0V), ground point c through the first pad 131 (or connect to 0V), and input a third constant current I3 through the third pad 133 at point b; that is, the large-resistance metal interconnect structure 10, which serves as the resistor to be measured Rtest, is connected in parallel with the resistor R2 on the second input branch 12. By measuring the third measurement voltage Vb at point b, the third parallel resistance value Rb = (Vb - V0) / I3 is calculated.

[0039] The formula for calculating the resistance of parallel resistors is known:

[0040] Formula (1): 1 / R1 + 1 / R2 = 1 / Rc

[0041] 1 / Rtest+1 / R1=1 / Ra Formula (2)

[0042] 1 / Rtest + 1 / R2 = 1 / Rb (Formula 3)

[0043] Subtracting formula (1) from formula (2) gives:

[0044] 1 / Rtest-1 / R2=1 / Ra-1 / Rc Formula (4)

[0045] Adding formula (3) and formula (4) together, we get:

[0046] 2 / Rtest=1 / Ra+1 / Rb-1 / Rc Formula (5)

[0047] Since Ra, Rb, and Rc have been measured and calculated as described above and are known values, the resistance value of the resistor to be tested, Rtest, can be obtained according to formula (5).

[0048] Similarly, the resistance values ​​of resistors R1 and R2 can also be determined through calculation. That is, the processing module 15 is also used to obtain the resistance values ​​of the first input branch 11 and the second input branch 12 according to the first parallel resistance value, the second parallel resistance value and the third parallel resistance value.

[0049] Specifically, subtracting formula (3) from formula (2) yields:

[0050] Formula (6) = 1 / R1 - 1 / R2 = 1 / Ra - 1 / Rb

[0051] Adding formula (1) to formula (6), we get:

[0052] 2 / R1=1 / Rc+1 / Ra-1 / Rb Formula (7)

[0053] Subtracting formula (1) from formula (6), we get:

[0054] 2 / R21=1 / Rc-1 / Ra+1 / Rb Formula (8)

[0055] Since Ra, Rb, and Rc have been measured and calculated as described above and are known values, the resistance value of resistor R1 on the first inlet branch 11 can be obtained according to formula (7); the resistance value of resistor R2 on the second inlet branch 12 can be obtained according to formula (8).

[0056] Please refer to the following: Figures 3-4 ,in, Figure 3 This is a schematic diagram of the architecture of a resistance measurement device with a large-resistance metal interconnect structure provided in another embodiment of the present invention. Figure 4 for Figure 3 The diagram shows the principle of the device for obtaining parallel resistance values. The arrows in the diagram indicate one direction of current flow during measurement.

[0057] like Figure 3 As shown, with Figure 1 The difference in the illustrated embodiment is that, in this embodiment, the branch common node 10C, the first end 10A, and the second end 10B are electrically connected to two pads respectively for input / output of electrical signals, which can avoid signal interference and improve measurement accuracy.

[0058] Specifically, the test pad group 33 includes two first pads 3311 and 3312 electrically connected to the branch common node 10C. During measurement, one of the first pads 3311 is used to receive a first constant current I1 or apply a first voltage V1, and the other first pad 3312 is used to output the first measurement voltage Vtest1 or the first measurement current Itest1. For example, when measuring the first parallel resistance Rc of the first inlet branch 11 and the second inlet branch 12, the measurement module 14 provides a first constant current I1 to one of the first pads 3311 and collects the first measurement voltage Vtest1 on the other first pad 3312; or, the measurement module 14 applies the first voltage V1 to one of the first pads 3311 and collects the first measurement current Itest1 on the other first pad 3312.

[0059] Specifically, the test pad group 33 includes two second pads 3321 and 3322 electrically connected to the first terminal 10A. During measurement, one of the second pads 3321 is used to receive a second constant current I2 or apply a second voltage V2, and the other second pad 3322 is used to output a second measurement voltage Vtest2 or a second measurement current Itest2. For example, when measuring the second parallel resistance Ra of the first inlet branch 11 and the large-resistance metal interconnect structure 10, the measurement module 14 provides a second constant current I2 to one of the second pads 3321 and collects the second measurement voltage Vtest2 on the other second pad 3322; or, the measurement module 14 applies a second voltage V2 to one of the second pads 3321 and collects the second measurement current Itest2 on the other second pad 3322.

[0060] Specifically, the test pad group 33 includes two third pads 3331 and 3332 electrically connected to the second terminal 10B. During measurement, one of the third pads 3331 is used to receive a third constant current I3 or apply a third voltage V3, and the other third pad 3332 is used to output a third measurement voltage Vtest3 or a third measurement current Itest3. For example, when measuring the third parallel resistance Rb of the second input branch 12 connected in parallel with the large-resistance metal interconnect structure 10, the measurement module 14 provides a third constant current I3 to one of the third pads 3331 and collects the third measurement voltage Vtest3 on the other third pad 3332; or, the measurement module 14 applies a third voltage V3 to one of the third pads 3331 and collects the third measurement current Itest3 on the other third pad 3332.

[0061] In some embodiments, the distance from one of the two pads connected to the same node or end to the node or end is less than the distance from the other pad to the node or end; when a voltage is applied to the pad, the voltage is applied to the pad closer to the node or end, so as to reduce the line length through which the input voltage passes, reduce the voltage drop of the line itself, and improve measurement accuracy.

[0062] Based on the same inventive concept, the present invention also provides a method for measuring the resistance of a high-resistivity metal interconnect structure. The method can be implemented by using the measuring device described above in the present invention to measure the resistance of the high-resistivity metal interconnect structure.

[0063] Please see Figure 5 This is a flowchart illustrating a method for measuring the resistance of a large-resistance metal interconnect structure according to an embodiment of the present invention. The large-resistance metal interconnect structure has a first end and a second end. The method in this embodiment includes the following steps: S51, providing a resistance measuring device for a large-resistance metal interconnect structure, wherein a first input branch of the device is electrically connected between the first end and a common node of the branch, a second input branch of the device is electrically connected between the second end and the common node of the branch, a first pad in the test pad group of the device is electrically connected to the common node of the branch, a second pad in the test pad group is electrically connected to the first end, and a third pad in the test pad group is electrically connected to the second end. The first input branch includes at least one first input resistor, and the second input branch includes at least one second input resistor; S52, providing a first constant current or applying a first voltage to the first pad, applying a common voltage to the second pad and the third pad, and acquiring a first measurement voltage or a first measurement current on the first pad; S53, providing a first constant current or applying a first voltage to the second pad. S53: Provide a second constant current or apply a second voltage, apply the common voltage to the first pad and the third pad, and acquire a second measured voltage or a second measured current on the second pad; S54: Provide a third constant current or apply a third voltage to the third pad, apply the common voltage to the first pad and the second pad, and acquire a third measured voltage or a third measured current on the third pad; and S55: Obtain a first parallel resistance value of the first input branch and the second input branch connected in parallel based on the first measured voltage or the first measured current, obtain a second parallel resistance value of the first input branch and the large-resistance metal interconnect structure connected in parallel based on the second measured voltage or the second measured current, obtain a third parallel resistance value of the second input branch and the large-resistance metal interconnect structure connected in parallel based on the third measured voltage or the third measured current, and obtain the resistance value of the large-resistance metal interconnect structure based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value. Steps S52, S53, and S54 are performed time-sharingly, but the order is not restricted. For the specific execution method of each step, please refer to... Figures 1-4 Detailed description of the measuring device shown.

[0064] In some embodiments, the first parallel resistance value Rc, the second parallel resistance value Ra, and the third parallel resistance value Rb are obtained by the following formulas:

[0065] Rc=(Vc-V0) / Ic, Ra=(Va-V0) / Ia, Rb=(Vb-V0) / Ib;

[0066] Wherein, V0 is the common voltage; Vc is the first measuring voltage and Ic is the first constant current, or Vc is the first voltage and Ic is the first measuring current; Va is the second measuring voltage and Ia is the second constant current, or Va is the second voltage and Ia is the second measuring current; Vb is the third measuring voltage and Ib is the third constant current, or Vb is the third voltage and Ib is the third measuring current.

[0067] In some embodiments, the resistance value of the high-resistance metal interconnect structure 11 (i.e., the resistance under test Rtest) is obtained by the following formula:

[0068] 2 / Rtest = 1 / Ra + 1 / Rb - 1 / Rc;

[0069] Where Rtest is the resistance value of the resistor to be tested, Rc is the first parallel resistance value, Ra is the second parallel resistance value, and Rb is the third parallel resistance value.

[0070] In some embodiments, step S55 further includes: obtaining the resistance values ​​of the first input branch and the second input branch respectively based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value. Specific resistance calculation formulas can be found in the aforementioned formulas (7) and (8), and will not be repeated here.

[0071] In the above embodiments, by adding an input branch and controlling the input signal of the corresponding pad, the input resistors on the input branch form parallel circuits with the large-resistance metal interconnect structure. The parallel resistance value of the parallel circuit is then obtained based on the corresponding measurement results, thereby obtaining the resistance value of the large-resistance metal interconnect structure. This allows for accurate measurement of ultra-large resistance values ​​and accurate measurement of the input resistor value. Furthermore, the input resistor on the input branch can be a single resistor or multiple resistors connected in series; and the resistor material and thickness are not limited, improving the flexibility of the resistance measurement device and facilitating its widespread application. Further control of the input resistor to have a smaller value improves measurement accuracy, reduces the influence of the input resistor on the large-resistance metal interconnect structure under test, and reduces the manufacturing cost of the input resistor.

[0072] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "also includes a…" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A resistance measuring device for a high-resistance metal interconnect structure, wherein the high-resistance metal interconnect structure has opposing first and second ends; characterized in that, The device includes: A first inlet branch is electrically connected between the first end and a common node of a branch, and the first inlet branch includes at least one first inlet resistor; A second inlet branch is electrically connected between the second terminal and the common node of the branch, and the second inlet branch includes at least one second inlet resistor; A test pad assembly, the test pad assembly comprising a first pad electrically connected to the branch common node, a second pad electrically connected to the first end, and a third pad electrically connected to the second end; The measurement module is configured to provide a first constant current or apply a first voltage to the first pad, apply a common voltage to the second pad and the third pad, and acquire a first measured voltage or a first measured current on the first pad; and to provide a second constant current or apply a second voltage to the second pad, apply the common voltage to the first pad and the third pad, and acquire a second measured voltage or a second measured current on the second pad; and to provide a third constant current or apply a third voltage to the third pad, apply the common voltage to the first pad and the second pad, and acquire a third measured voltage or a third measured current on the third pad, wherein the first voltage, the second voltage, and the third voltage are all greater than the common voltage; The processing module is configured to obtain a first parallel resistance value of the first input branch and the second input branch connected in parallel based on a first measured voltage or a first measured current; obtain a second parallel resistance value of the first input branch and the large-resistance metal interconnect structure connected in parallel based on a second measured voltage or a second measured current; obtain a third parallel resistance value of the second input branch and the large-resistance metal interconnect structure connected in parallel based on a third measured voltage or a third measured current; and obtain the resistance value of the large-resistance metal interconnect structure based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value. The total resistance of the first input branch and the total resistance of the second input branch are both less than the resistance of the large-resistance metal interconnect structure.

2. The apparatus according to claim 1, characterized in that, The first introducing resistor, the second introducing resistor, and the large-resistance metal interconnect structure are manufactured using the same process.

3. The structure according to claim 1, characterized in that, The first inlet branch includes a plurality of first inlet resistors connected in series, and / or the second inlet branch includes a plurality of second inlet resistors connected in series.

4. The apparatus according to claim 1, characterized in that, The first constant current, the second constant current, and the third constant current have the same current value; the first voltage, the second voltage, and the third voltage have the same voltage value.

5. The apparatus according to claim 1, characterized in that, The measurement module employs a source measurement unit to provide a voltage source with a measurement resolution of less than 1mV or a current source with a measurement resolution of less than 1uA; the processing module employs a microprocessor.

6. The apparatus according to claim 1, characterized in that, The processing module is further configured to obtain the resistance values ​​of the first input branch and the second input branch based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value, respectively.

7. The apparatus according to claim 1, characterized in that, The test pad group includes two first pads electrically connected to the common node of the branch. During measurement, one of the first pads is used to receive the first constant current or the first voltage, and the other first pad is used to output the first measurement voltage or the first measurement current. The test pad group includes two second pads electrically connected to the first end. During measurement, one of the second pads is used to receive the second constant current or the second voltage, and the other second pad is used to output the second measurement voltage or the second measurement current. The test pad assembly includes two third pads electrically connected to the second end. During measurement, one of the third pads is used to receive the third constant current or the third voltage, and the other third pad is used to output the third measurement voltage or the third measurement current.

8. A method for measuring the resistance of a high-resistance metal interconnect structure, wherein the high-resistance metal interconnect structure has opposing first and second ends; characterized in that, The method includes the following steps: A resistance measurement device for a large-resistance metal interconnect structure is provided. A first input branch of the device is electrically connected between a first terminal and a common node of the branch. A second input branch of the device is electrically connected between a second terminal and the common node of the branch. A first pad in a test pad group is electrically connected to the common node of the branch, a second pad in the test pad group is electrically connected to the first terminal, and a third pad in the test pad group is electrically connected to the second terminal. The first input branch includes at least one first input resistor, and the second input branch includes at least one second input resistor. The total resistance of both the first input branch and the second input branch is less than the resistance of the large-resistance metal interconnect structure. A first constant current or a first voltage is applied to the first pad, a common voltage is applied to the second pad and the third pad, and a first measured voltage or a first measured current is acquired on the first pad; Provide a second constant current or apply a second voltage to the second pad, apply the common voltage to the first pad and the third pad, and acquire a second measured voltage or a second measured current on the second pad; Provide a third constant current or apply a third voltage to the third pad, apply the common voltage to the first pad and the second pad, and acquire a third measured voltage or a third measured current on the third pad; as well as The first parallel resistance value of the first input branch and the second input branch connected in parallel is obtained according to the first measured voltage or the first measured current. The second parallel resistance value of the first input branch and the large-resistance metal interconnect structure connected in parallel is obtained according to the second measured voltage or the second measured current. The third parallel resistance value of the second input branch and the large-resistance metal interconnect structure connected in parallel is obtained according to the third measured voltage or the third measured current. The resistance value of the large-resistance metal interconnect structure is obtained according to the first parallel resistance value, the second parallel resistance value and the third parallel resistance value.

9. The method according to claim 8, characterized in that, The first parallel resistance value is obtained by the following formula: Rc = (Vc - V0) / Ic, Wherein, Rc is the first parallel resistance value, V0 is the common voltage, Vc is the first measured voltage, and Ic is the first constant current, or, Vc is the first voltage and Ic is the first measured current. The second parallel resistance value is obtained by the following formula: Ra = (Va - V0) / Ia, Wherein, Ra is the second parallel resistance value, V0 is the common voltage, Va is the second measured voltage, and Ia is the second constant current, or Va is the second voltage and Ia is the second measured current; The third parallel resistance value is obtained by the following formula: Rb = (Vb - V0) / Ib, Wherein, Rb is the third parallel resistance value, V0 is the common voltage, Vb is the third measured voltage, and Ib is the third constant current, or Vb is the third voltage and Ib is the third measured current; The resistance value of the high-resistance metal interconnect structure is obtained by the following formula: 2 / Rtest=1 / Ra+1 / Rb-1 / Rc, Wherein, Rtest is the resistance value of the high-resistance metal interconnect structure.

10. The method according to claim 8, characterized in that, The step of obtaining the resistance value of the large-resistance metal interconnect structure based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value further includes: obtaining the resistance values ​​of the first input branch and the second input branch respectively based on the first parallel resistance value, the second parallel resistance value, and the third parallel resistance value.

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