Resistance test structure, resistance test method and semiconductor structure

Abstract

The application relates to the technical field of semiconductors, in particular to a resistance test structure, a resistance test method and a semiconductor structure. The resistance test structure comprises a resistance structure to be tested; the resistance structure to be tested comprises metal wires of different types or through holes connecting different metal layers; a preset number of pads, the resistance structure to be tested is located in a circuit between two adjacent pads in the preset number of pads; a diode is located in a circuit between the resistance structure to be tested and a target pad, and the target pad is one of two adjacent thermal pads; wherein the resistance test structure is used to measure the resistance of the metal wires of different types or the resistance of the through holes connecting the different metal layers under the condition that a forward voltage or a negative voltage is applied to the diode. The application can test the resistance of the metal wires of different types or the through holes connecting the different metal layers by multiplexing the preset number of test pads, thereby reducing the consumption of pad resources and wafer area.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing, and in particular to a resistance testing structure, a resistance testing method, and a semiconductor structure. Background Technology

[0002] In the chip manufacturing process, circuits of different structures are typically stacked layer by layer. The front-end stacking of integrated circuits mainly involves gates and contact holes, while the back-end stacking mainly involves vias and metal lines. The vias and metal lines in the back-end stack are fabricated using different colors and either a litho-freeze-litho-etch (LELE) or self-aligned double patterning (SADP) process.

[0003] When performing stress migration testing on semiconductor devices, the four-terminal method is typically used to test the resistance of metal lines and vias. This method requires a large number of test pads (for example, if N pads are needed to test the resistance of a metal line of one color, then an additional N pads are needed to test the resistance of a metal line of another color, resulting in a total of 2N pads). The use of more test pads increases the consumption of pad resources and wafer area, thereby increasing wafer production costs. In addition, the use of more test pads also reduces the efficiency of resistance testing. Summary of the Invention

[0004] This application provides a resistance testing structure, a resistance testing method, and a semiconductor structure to at least solve the aforementioned problems existing in the related technologies.

[0005] To solve the above-mentioned technical problems, the technical solution of this application is as follows:

[0006] According to a first aspect of the embodiments of this application, a resistance testing structure is provided, the resistance testing structure comprising:

[0007] The resistor under test structure includes different types of metal wires or through-holes connecting different metal layers.

[0008] A preset number of solder pads are provided, and the resistor structure under test is located in the circuit between two adjacent solder pads among the preset number of solder pads.

[0009] A diode is located in the circuit between the resistor under test structure and the target pad, wherein the target pad is one of the two adjacent thermal pads.

[0010] The resistance testing structure is used to measure the resistance of different types of metal wires when a positive or negative voltage is applied to the diode, or to measure the resistance of vias connecting different metal layers when a positive or negative voltage is applied to the diode.

[0011] In an optional embodiment, the resistor under test structure includes different types of metal wires, and the preset number of pads include a first pad, a second pad, a third pad, and a fourth pad arranged in sequence. A circuit for providing current is formed between the second pad and the third pad, and a circuit for measuring voltage is formed between the first pad and the fourth pad.

[0012] The resistor under test is located in the circuit between the second pad and the third pad;

[0013] The target pad is the second pad, and the diode is disposed in the circuit between the second pad and the different types of metal wires.

[0014] In an optional embodiment, the resistor under test structure includes a first type of metal wire and a second type of metal wire, and the diode includes a first diode and a second diode. The first diode is disposed in the circuit between the second pad and the first type of metal wire, and the second diode is disposed in the circuit between the second pad and the second type of metal wire. The positive and negative terminals of the first diode are arranged in opposite directions to those of the second diode.

[0015] In an optional embodiment, the second pad is connected to the positive terminal of the first diode, the negative terminal of the first diode is connected to the first type of metal wire, the second pad is connected to the negative terminal of the second diode, and the positive terminal of the second diode is connected to the second type of metal wire.

[0016] The resistance test structure is used to provide a first current to the first type of metal line through the circuit between the second and third pads when a positive voltage is applied to the first diode, and to measure a first voltage of the first type of metal line through the circuit between the first and fourth pads, and to determine the resistance of the first type of metal line based on the ratio of the first voltage to the first current.

[0017] The resistance test structure is used to provide a second current to the second type of metal line through the circuit between the second pad and the third pad when a negative voltage is applied to the second diode, and to measure a second voltage of the second type of metal line through the circuit between the first pad and the fourth pad, and to determine the resistance of the second type of metal line based on the ratio of the second voltage to the second current.

[0018] In an optional embodiment, the resistor under test structure includes through-holes connecting different metal layers, and the preset number of pads includes a first pad, a second pad, a third pad, and a fourth pad arranged in sequence. A circuit for providing current is formed between the first pad and the second pad, and a circuit for measuring voltage is formed between the third pad and the fourth pad.

[0019] The resistor under test is located between the second pad and the third pad;

[0020] The target pad is the second pad, and the diode is disposed in the circuit between the second pad and the via connecting different metal layers.

[0021] In an optional embodiment, the resistor under test structure includes a first through-hole and a second through-hole connecting different metal layers, and the diode includes a third diode and a fourth diode. The third diode is disposed in the circuit between the second pad and the first through-hole, and the fourth diode is disposed in the circuit between the second pad and the second through-hole. The positive and negative terminals of the third diode are arranged in opposite directions to those of the fourth diode.

[0022] In an optional embodiment, the second pad is connected to the negative terminal of the third diode, the positive terminal of the third diode is connected to the first via, the second pad is connected to the positive terminal of the fourth diode, and the negative terminal of the fourth diode is connected to the second via.

[0023] The resistance test structure is used to provide a third current to the second via through the circuit between the first pad and the second pad when a positive voltage is applied to the fourth diode, and is used to measure a third voltage of the second via through the circuit between the third pad and the fourth pad, and to determine the resistance of the second via based on the ratio of the third voltage to the third current.

[0024] The resistance test structure is used to provide a fourth current to the first via through the circuit between the first pad and the second pad when a negative voltage is applied to the third diode, and to measure a fourth voltage of the first via through the circuit between the third pad and the fourth pad, and to determine the resistance of the first via based on the ratio of the fourth voltage to the fourth current.

[0025] A second aspect of this application provides a resistance testing method, wherein the resistance testing method is performed using a resistance testing structure as described in any of the above embodiments, and the resistance testing method includes:

[0026] When a positive or negative voltage is applied to a diode, the current flowing through different types of metal lines and the voltage on different types of metal lines are measured through a preset number of pads; based on the current flowing through different types of metal lines and the voltage on different types of metal lines, the resistance of different types of metal lines is obtained.

[0027] Alternatively, when a positive or negative voltage is applied to the diode, the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers are measured through the preset number of pads; based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, the resistance of the vias connecting different metal layers is obtained.

[0028] In an optional embodiment, the preset number of solder pads includes a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged sequentially. A circuit for providing current is formed between the second solder pad and the third solder pad, and a circuit for measuring voltage is formed between the first solder pad and the fourth solder pad. The resistor under test structure includes a first type of metal wire and a second type of metal wire. The diode includes a first diode and a second diode. The first diode is disposed in the circuit between the second solder pad and the first type of metal wire, and the second diode is disposed in the circuit between the second solder pad and the second type of metal wire.

[0029] When a positive or negative voltage is applied to the diode, the current flowing through different types of metal lines and the voltage on the different types of metal lines are measured using a preset number of pads; based on the current flowing through the different types of metal lines and the voltage on the different types of metal lines, the resistance of the different types of metal lines is obtained, including:

[0030] When a forward voltage is applied to the first diode, a first current is provided to the first type of metal line through the circuit between the second and third pads, a first voltage of the first type of metal line is measured through the circuit between the first and fourth pads, and the resistance of the first type of metal line is determined based on the ratio of the first voltage to the first current.

[0031] When a negative voltage is applied to the second diode, a second current is provided to the first type of metal line through the circuit between the second and third pads, a second voltage of the second type of metal line is measured through the circuit between the first and fourth pads, and the resistance of the second type of metal line is determined based on the ratio of the second voltage to the second current.

[0032] In an optional embodiment, the preset number of solder pads includes a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged sequentially. A circuit for providing current is formed between the first solder pad and the second solder pad, and a circuit for measuring voltage is formed between the third solder pad and the fourth solder pad. The resistor under test structure includes a first through-hole and a second through-hole connecting different metal layers. The diode includes a third diode and a fourth diode. The third diode is disposed in the circuit between the second solder pad and the first through-hole, and the fourth diode is disposed in the circuit between the second solder pad and the second through-hole.

[0033] When a positive or negative voltage is applied to the diode, the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers are measured through the preset number of pads; based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, the resistance of the vias connecting different metal layers is obtained, including:

[0034] When a forward voltage is applied to the fourth diode, a third current is provided to the second via through the circuit between the first and second pads, a third voltage of the second via is measured through the circuit between the third and fourth pads, and the resistance of the second via is determined based on the ratio of the third voltage to the third current.

[0035] When a negative voltage is applied to the third diode, a fourth current is provided to the first via through the circuit between the first pad and the second pad, a fourth voltage is measured on the metal line of the first via through the circuit between the third pad and the fourth pad, and the resistance of the first via is determined based on the ratio of the fourth voltage to the fourth current.

[0036] A third aspect of this application provides a semiconductor structure, the semiconductor structure including a device region and a non-device region, wherein vias or metal lines as described in any of the above embodiments are located in the device region, and a predetermined number of pads as described in any of the above embodiments are located in the non-device region.

[0037] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects:

[0038] This application provides a resistance testing structure, a resistance testing method, and a semiconductor structure. The resistance testing structure includes a resistor under test (DUT); a preset number of bonding pads, with the DUT located in a circuit between two adjacent bonding pads; and a diode located in a circuit between the DUT and a target bonding pad, where the target bonding pad is one of the two adjacent thermal bonding pads. Since the DUT includes different types of metal lines or vias connecting different metal layers, the resistance of different types of metal lines can be measured when a positive or negative voltage is applied to the diode. This allows for the reuse of a preset number of test bonding pads to test the resistance of different types of metal lines, reducing the consumption of bonding pad resources and wafer area during the resistance testing process, thereby reducing wafer production costs and improving the testing efficiency for different types of metal lines. When a positive or negative voltage is applied to the diode, the resistance of vias connecting different metal layers can be measured. This allows for the reuse of a preset number of test pads to test the resistance of vias connecting different metal layers, reducing the consumption of pad resources and wafer area during the resistance testing process, thereby reducing wafer production costs and improving the testing efficiency of vias connecting different metal layers.

[0039] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0040] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application, and do not constitute an undue limitation of this application.

[0041] Figure 1 This is a schematic diagram of a resistance test structure according to an exemplary embodiment.

[0042] Figure 2 This is a schematic diagram of a four-terminal resistance testing apparatus according to an exemplary embodiment.

[0043] Figure 3This is a schematic diagram of a resistance test structure according to an exemplary embodiment. Figure 2 .

[0044] Figure 4 This is a schematic diagram of a resistance test structure according to an exemplary embodiment. Figure 3 .

[0045] In the figure, the corresponding labels are: 1-first pad, 2-second pad, 3-third pad, 4-fourth pad, 5-first type metal wire, 6-second type metal wire, 7-first diode, 8-second diode, 9-voltage measurement probe, 10-current input probe, 11-current output probe, 12-first via, 13-second via, 14-third diode, 15-fourth diode. Detailed Implementation

[0046] The following provides numerous different embodiments or instances for implementing various features of the provided subject matter. Specific examples of elements and configurations are described below in a simplified manner. Of course, these elements and configurations are merely examples and are not intended to be limiting. For example, the formation of an initial feature above or on a second feature in the following description may include embodiments where the initial and second features are formed in direct contact, and may also include embodiments where additional features may be formed between the initial and second features such that the initial and second features do not need to be in direct contact. Furthermore, references to numbers and / or letters may be repeated in various instances throughout this application. This repetition is for simplicity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0047] Additionally, spatial relative terms, such as “below,” “under,” “lower part,” “above,” “upper part,” “front,” “back,” “above,” and similar terms, may be used in this application for ease of description to describe the relationship between one element or feature as illustrated in the figures and another element(s). Spatial relative terms are intended to cover different orientations in the use or operation of the device other than those depicted in the figures.

[0048] This application provides a resistance testing structure, which includes:

[0049] The resistor under test structure includes different types of metal wires or through-holes connecting different metal layers.

[0050] A preset number of solder pads are provided, and the resistor structure under test is located in the circuit between two adjacent solder pads among the preset number of solder pads.

[0051] A diode is located in the circuit between the resistor under test structure and the target pad, wherein the target pad is any one of the two adjacent thermal pads.

[0052] The resistance testing structure is used to measure the resistance of different types of metal wires when a positive or negative voltage is applied to the diode, or to measure the resistance of vias connecting different metal layers when a positive or negative voltage is applied to the diode.

[0053] Optionally, the number of the preset number of pads can be set according to actual needs, and there is no specific limitation. For example, the number of the preset number of pads is 4. Some of the pads form a circuit to provide current, and the remaining pads form a circuit to measure voltage.

[0054] It should be noted that the preset number of solder pads can be arranged in any way, and no specific limitation is made here. For example, the preset number of solder pads can be arranged in a row.

[0055] Optionally, the resistor under test is located in the circuit between two adjacent pads from a preset number of pads. Either of these two adjacent pads can be designated as the target pad, and a diode can be placed in the current flow between the resistor under test and the target pad.

[0056] In one approach, the resistor under test (DUT) structure comprises different types of metal wires. Because different techniques are used in the fabrication of the metal wires during advanced back-end processing, this directly affects the color representation of the metal wires and vias. Therefore, these different types of metal wires can be made of different materials, resulting in different colors. Thus, different types of metal wires can be considered as metal wires of different colors. When a positive or negative voltage is applied to the diode, the resistance of these different types of metal wires can be measured using the four-terminal method. Specifically, the process of measuring the resistance of different types of metal wires using the four-terminal method involves: providing current to the different types of metal wires through a portion of a predetermined number of solder pads; measuring the voltage across the different types of metal wires through the remaining solder pads of the predetermined number of solder pads; and calculating the resistance of the different types of metal wires by using the ratio of the measured voltage to the current.

[0057] In another approach, the resistor under test structure includes vias connecting different metal layers. For example, if the semiconductor structure includes three metal layers, there are two vias: one via connects to a metal line in the first metal layer and a metal line in the second metal layer, and the other via connects to a metal line in the second metal layer and a metal line in the third metal layer. When a positive or negative voltage is applied to the diode, the resistance of the via connecting different metal layers can be measured using the four-terminal method. Specifically, the process of measuring the resistance of the via connecting different metal layers using the four-terminal method can be as follows: current is supplied to the via connecting different metal layers through a portion of a predetermined number of solder pads; the voltage across the via connecting different metal layers is measured through the remaining solder pads of the predetermined number of solder pads; and the resistance of the via connecting different metal layers is calculated using the ratio of the measured voltage to the current.

[0058] Because the resistor under test (DUT) structure includes different types of metal lines or vias connecting different metal layers, the resistance of different types of metal lines can be measured when a positive or negative voltage is applied to the diode. This allows for the reuse of a predetermined number of test pads to test the resistance of different types of metal lines, reducing the consumption of pad resources and wafer area during the resistance testing process, thereby lowering wafer production costs and improving testing efficiency. Similarly, when a positive or negative voltage is applied to the diode, the resistance of vias connecting different metal layers can be measured. This also allows for the reuse of a predetermined number of test pads to test the resistance of vias connecting different metal layers, reducing the consumption of pad resources and wafer area during the resistance testing process, thereby lowering wafer production costs and improving testing efficiency.

[0059] The following explanation uses different types of metal wires as examples to illustrate the resistance testing structure.

[0060] Figure 1 This is a schematic diagram of a resistance test structure according to an exemplary embodiment. Figure 1 ,like Figure 1 As shown, the preset number of solder pads includes a first solder pad 1, a second solder pad 2, a third solder pad 3, and a fourth solder pad 4 arranged in sequence. A circuit for providing current is formed between the second solder pad 2 and the third solder pad 3, and a circuit for measuring voltage is formed between the first solder pad 1 and the fourth solder pad 4.

[0061] The resistor under test (UUT) structure is located in the circuit between the second pad 2 and the third pad 3, and the UUT structure includes different types of metal wires. The target pad is the second pad 2, and the diode is disposed in the circuit between the second pad 2 and the different types of metal wires.

[0062] It should be noted that the resistor under test structure includes different types of metal wires, i.e., metal wires of different colors, and the number of diodes matches the color of the metal wires. The second pad 2 forms a corresponding circuit with each type of metal wire, and a corresponding diode is placed in each of these circuits. For example, if there are two colors of metal wires, then there are two diodes, and the second pad 2 forms different circuits with the two metal wires, with a corresponding diode placed in each circuit.

[0063] Therefore, by setting the number of solder pads to four, using the circuit between two of them as the current supply circuit and the circuit between the other two as the voltage measurement circuit, four-terminal testing can be completed with fewer solder pads, reducing the consumption of solder pad resources during resistance testing of different types of metal lines. In addition, by setting diodes in the circuit between the second solder pad and each type of metal line, the resistance of different types of metal lines can be tested by reusing a preset number of test pads, reducing the consumption of solder pad resources and wafer area during resistance testing of different types of metal lines, thereby reducing wafer production costs and improving the testing efficiency for resistance testing of different types of metal lines.

[0064] In an optional embodiment, the resistor under test structure includes a first type of metal line 5 and a second type of metal line 6, and the diode includes a first diode 7 and a second diode 8. The first diode 7 is disposed in the circuit between the second pad 2 and the first type of metal line 5, and the second diode 8 is disposed in the circuit between the second pad 2 and the second type of metal line 6. The positive and negative terminals of the first diode 7 are arranged in opposite directions to those of the second diode 8.

[0065] In this embodiment, continue as follows Figure 1 As shown, the resistor under test structure can include two types of metal wires, namely two colors of metal wires. These two types of metal wires can include a first type of metal wire 5 and a second type of metal wire 6. A circuit is formed between the second solder pad 2 and the first type of metal wire 5, and a first diode 7 is disposed in this circuit. A circuit is formed between the second solder pad 2 and the second type of metal wire 6, and a second diode 8 is disposed in this circuit.

[0066] It should be noted that since the resistance test is performed on different types of metal wires, if the positive and negative terminals of the diodes are set in the same direction, when the diodes are conducting, the circuit formed between the second pad 2 and the first type of metal wire, as well as the circuit between the second pad 2 and the second type of metal wire 6, will be conducted. Thus, the measured resistance is equivalent to the series connection of the resistances of the two types of metal wires. Based on this, the positive and negative terminals of the first diode 7 and the second diode 8 can be set in opposite directions. This ensures that only the metal wire being tested is conducting when measuring resistance. Therefore, it is possible to accurately test the resistance of different types of metal wires by reusing a preset number of test pads.

[0067] In an optional embodiment, the second pad 2 is connected to the positive terminal of the first diode 7, the negative terminal of the first diode 7 is connected to the first type of metal wire 5, the second pad 2 is connected to the negative terminal of the second diode 8, and the positive terminal of the second diode 8 is connected to the second type of metal wire 6.

[0068] The resistance test structure is used to provide a first current to the first type of metal line 5 when a positive voltage is applied to the first diode 7, and to measure a first voltage of the first type of metal line 5 through the circuit between the first pad 1 and the fourth pad 4, and to determine the resistance of the first type of metal line 5 according to the ratio of the first voltage to the first current.

[0069] The resistance test structure is used to provide a second current to the second type of metal line 6 when a negative voltage is applied to the second diode 8, and to measure a second voltage of the second type of metal line 6 through the circuit between the first pad 1 and the fourth pad 4, and to determine the resistance of the second type of metal line 6 based on the ratio of the second voltage to the second current.

[0070] First, the principle of resistance testing using the four-terminal method will be explained. Figure 2 This is a schematic diagram of a four-terminal resistance testing apparatus according to an exemplary embodiment, as shown below. Figure 2 As shown, the resistance testing device includes two voltage measurement probes 9, one current input probe 10, and one current output probe 11. A voltmeter is connected in series between the two voltage measurement probes 9, and an ammeter is connected in series between the current input probe 10 and the current output probe 11. During the test, the second pad 2 and the third pad 3 are connected to the current input probe 10 and the current output probe 11, respectively, while the first pad 1 and the second pad 2 are connected to the voltage measurement probes 9, respectively.

[0071] Continue as Figure 1As shown, the second pad 2 is connected to the positive terminal of the first diode 7, the negative terminal of the first diode 7 is connected to the first type of metal line 5, the second pad 2 is connected to the negative terminal of the second diode 8, and the positive terminal of the second diode 8 is connected to the second type of metal line 6. This achieves that the setting directions of the positive and negative terminals of the first diode 7 and the second diode 8 are opposite.

[0072] In one embodiment, when a forward voltage is applied to the first diode 7, current flows from the positive terminal to the negative terminal of the first diode 7, at which point the first diode 7 is in a conducting state. This allows a first current to be supplied to the first type of metal line 5 through the circuit between the second pad 2 and the third pad 3, and a first voltage to the first type of metal line 5 to be measured through the circuit between the first pad 1 and the fourth pad 4. The resistance of the first type of metal line 5 is then determined based on the ratio of the first voltage to the first current. However, since the second diode 8 is in a non-conducting state at this time, no current can be supplied to the second type of metal line 6, and therefore, the resistance of the second type of metal line 6 cannot be measured.

[0073] In another embodiment, when a negative voltage is applied to the second diode 8, current flows from the negative terminal to the positive terminal of the second diode 8. At this time, a second current can be supplied to the second type of metal line 6 through the circuit between the second pad 2 and the third pad 3, and a second voltage of the second type of metal line 6 can be measured through the circuit between the first pad 1 and the fourth pad 4. The resistance of the second type of metal line 6 is determined based on the ratio of the second voltage to the second current. However, since the first diode 7 is in a non-conducting state at this time, no current can be supplied to the first type of metal line 5, and therefore, the resistance of the first type of metal line 5 cannot be measured.

[0074] Therefore, by connecting the second pad to the positive terminal of the first diode, the negative terminal of the first diode to the first type of metal wire, the second pad to the negative terminal of the second diode, and the positive terminal of the second diode to the second type of metal wire, different types of metal wires can be tested during four-terminal testing. This avoids the defect that prevents different types of metal wires from being tested when the entire circuit is turned on, and improves the test accuracy of testing the resistance of different types of metal wires by reusing a preset number of test pads.

[0075] The following explanation uses a via connecting different metal layers as an example to illustrate the resistance test structure.

[0076] Figure 3This is a schematic diagram of a resistance test structure according to an exemplary embodiment. Figure 2 , Figure 4 This is a schematic diagram of a resistance test structure according to an exemplary embodiment. Figure 3 ,like Figure 3 and Figure 4 As shown, the preset number of solder pads includes a first solder pad 1, a second solder pad 2, a third solder pad 3, and a fourth solder pad 4 arranged in sequence. A circuit for providing current is formed between the first solder pad 1 and the second solder pad 2, and a circuit for measuring voltage is formed between the third solder pad 3 and the fourth solder pad 4.

[0077] The resistor under test structure is located between the second pad 2 and the third pad 3. The resistor under test structure includes a via connecting different metal layers. The target pad is the second pad 2. The diode is disposed in the circuit between the second pad 2 and the via connecting different metal layers.

[0078] It should be noted that the resistor under test structure includes vias connecting different metal layers, and the number of diodes matches the number of vias. Each of the second pad 2 and the vias connecting different metal layers forms a corresponding circuit, and a corresponding diode is placed in each of these circuits. For example, if there are two vias, then there are two diodes, and the second pad 2 forms different circuits with the two vias, with a corresponding diode in each circuit.

[0079] Therefore, by setting the number of solder pads to four, using the circuit between two of them as the current supply circuit and the circuit between the other two as the voltage measurement circuit, four-terminal testing can be completed with fewer solder pads, reducing the consumption of solder pad resources during the resistance testing of vias connecting different metal layers. Furthermore, by placing a diode in the circuit between the second solder pad 2 and the via connecting different metal layers, the resistance of vias connecting different metal layers can be tested by reusing a preset number of test pads, reducing the consumption of solder pad resources and wafer area during the resistance testing of vias connecting different metal layers, thereby reducing wafer production costs and improving the testing efficiency of the resistance testing of vias connecting different metal layers.

[0080] In an optional embodiment, continue as follows Figure 3As shown, the resistor under test structure includes a first through-hole 12 and a second through-hole 13 connecting different metal layers. The diodes include a third diode 14 and a fourth diode 15. The third diode 14 is disposed in the circuit between the second pad 2 and the first through-hole 12, and the fourth diode 15 is disposed in the circuit between the second pad 2 and the second through-hole 13. The positive and negative terminals of the third diode 14 are arranged in opposite directions to those of the fourth diode 15. In this embodiment, the circuits for measuring the first through-hole 12 and the second through-hole 13 are essentially separated using diodes.

[0081] It should be noted that since the resistance test is performed on vias connecting different metal layers, if the positive and negative terminals of the diodes are set in the same direction, when the diodes are conducting, the circuit formed between the second pad 2 and the first via 12, as well as the circuit between the second pad 2 and the first via 12, will be conducted. Thus, the measured resistance is equivalent to the resistance of the first via 12 and the second via 13 connected in series. Based on this, the positive and negative terminals of the third diode 14 can be set in opposite directions to those of the fourth diode 15. This ensures that only the via being tested is conducting when the resistance is measured. Therefore, by reusing a preset number of test pads, the resistance of vias connecting different metal layers can be accurately tested.

[0082] In an optional embodiment, the second pad 2 is connected to the negative terminal of the third diode 14, the positive terminal of the third diode 14 is connected to the first through hole 12, the second pad 2 is connected to the positive terminal of the fourth diode 15, and the negative terminal of the fourth diode 15 is connected to the second through hole 13.

[0083] The resistance test structure is used to provide a third current to the second via 13 through the circuit between the first pad 1 and the second pad 2 when a positive voltage is applied to the fourth diode 15, and is used to measure the third voltage of the second via 13 through the circuit between the third pad 3 and the fourth pad 4, and to determine the resistance of the second via 13 according to the ratio of the third voltage to the third current.

[0084] The resistance test structure is used to provide a fourth current to the first via 12 through the circuit between the first pad 1 and the second pad 2 when a negative voltage is applied to the third diode 14, and is used to measure a fourth voltage of the first via 12 through the circuit between the third pad 3 and the fourth pad 4, and to determine the resistance of the first via 12 based on the ratio of the fourth voltage to the fourth current.

[0085] Optionally, continue as follows Figure 3 and Figure 4 As shown, the second pad 2 is connected to the negative terminal of the third diode 14, the positive terminal of the third diode 14 is connected to the first through hole 12, the second pad 2 is connected to the positive terminal of the fourth diode 15, and the negative terminal of the fourth diode 15 is connected to the second through hole 13. This achieves that the setting directions of the positive and negative terminals of the third diode 14 and the fourth diode 15 are opposite.

[0086] Optionally, during the resistance test using the four-terminal method, the first pad 1 and the second pad 2 are connected to the current input probe 10 and the current output probe 11, respectively, and the third pad 3 and the fourth pad 4 are connected to the voltage measurement probe 9, respectively.

[0087] In one implementation, continue as follows Figure 4 As shown, when a positive voltage is applied to the fourth diode 15, current flows from the positive terminal to the negative terminal of the fourth diode 15, making the fourth diode 15 conductive. This allows a third current to flow through the circuit between the first pad 1 and the second pad 2 to the second via 13, and a third voltage to be measured through the circuit between the third pad 3 and the fourth pad 4. The resistance of the second via 13 is then determined based on the ratio of the third voltage to the third current. However, since the third diode 14 is not conductive at this time, it cannot provide current to the first via 12, and therefore, the resistance of the first via 12 cannot be measured.

[0088] In another implementation, continue as follows Figure 3 As shown, when a negative voltage is applied to the third diode 14, current flows from the negative terminal to the positive terminal of the third diode 14. At this time, a fourth current can be provided to the first via 12 through the circuit between the first pad 1 and the second pad 2, and a fourth voltage of the first via 12 can be measured through the circuit between the third pad 3 and the fourth pad 4. The resistance of the first via 12 is determined based on the ratio of the fourth voltage to the fourth current. However, since the fourth diode 15 is in a non-conducting state at this time, it cannot provide current to the second via 13, and therefore, the resistance of the second via 13 cannot be measured.

[0089] Therefore, by connecting the second pad 2 to the negative terminal of the third diode 14, the positive terminal of the third diode 14 to the first via 12, the second pad 2 to the positive terminal of the fourth diode 15, and the negative terminal of the fourth diode 15 to the second via 13, the vias connected to different metal layers can be tested during four-terminal testing. This avoids the defect that prevents testing of vias connected to different metal layers when the entire circuit is conducting, and improves the testing accuracy of testing the resistance of vias connected to different metal layers by reusing a preset number of test pads.

[0090] This application embodiment also provides a resistance testing method, wherein the resistance testing method is obtained by using the resistance testing structure described in any of the above embodiments, and the resistance testing method includes:

[0091] When a positive or negative voltage is applied to a diode, the current flowing through different types of metal lines and the voltage on different types of metal lines are measured through a preset number of pads; based on the current flowing through different types of metal lines and the voltage on different types of metal lines, the resistance of different types of metal lines is obtained.

[0092] Alternatively, when a positive or negative voltage is applied to the diode, the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers are measured through the preset number of pads; based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, the resistance of the vias connecting different metal layers is obtained.

[0093] In one embodiment, the resistance testing process for different types of metal wires involves the following steps: When a forward voltage is applied to a diode, the current flowing through one type of metal wire and the voltage on that type of metal wire can be measured using a preset number of pads; the resistance of that type of metal wire is then determined based on the current and voltage. Similarly, when a negative voltage is applied to a diode, the current flowing through another type of metal wire and the voltage on that type of metal wire can be measured using a preset number of pads; the resistance of that other type of metal wire is then determined based on the current and voltage. This ensures that only the metal wire being tested is conductive when testing different types of metal wires, thus enabling accurate resistance testing of different types of metal wires by reusing a preset number of test pads.

[0094] In another embodiment, for testing the resistance of vias connecting different metal layers, when a forward voltage is applied to the diode, the current flowing through one via and the voltage of that via can be measured using the predetermined number of pads; the resistance of the via is obtained based on the current flowing through the via and the voltage of that via. When a negative voltage is applied to the diode, the current flowing through another via and the voltage of that other via can be measured using the predetermined number of pads; the resistance of that other via is obtained based on the current flowing through the other via and the voltage of that other via. Thus, it is possible to accurately test the resistance of vias connecting different metal layers by reusing a predetermined number of test pads.

[0095] In an optional embodiment, when a positive or negative voltage is applied to the diode, measuring the current flowing through different types of metal lines and the voltage on the different types of metal lines using a preset number of pads; and obtaining the resistance of different types of metal lines based on the current flowing through the different types of metal lines and the voltage on the different types of metal lines, includes:

[0096] When a positive voltage is applied to the first diode 7, a first current is provided to the first type of metal line 5 through the circuit between the second pad 2 and the third pad 3, a first voltage of the first type of metal line 5 is measured through the circuit between the first pad 1 and the fourth pad 4, and the resistance of the first type of metal line 5 is determined according to the ratio of the first voltage to the first current.

[0097] When a negative voltage is applied to the second diode 8, a second current is provided to the first type of metal line 5 through the circuit between the second pad 2 and the third pad 3, a second voltage of the second type of metal line 6 is measured through the circuit between the first pad 1 and the fourth pad 4, and the resistance of the second type of metal line 6 is determined based on the ratio of the second voltage to the second current.

[0098] In one implementation, continue as follows Figure 1 As shown, when a forward voltage is applied to the first diode 7, current flows from the positive terminal to the negative terminal of the first diode 7, making the first diode 7 conductive. This allows a first current to be supplied to the first type of metal line 5 through the circuit between the second pad 2 and the third pad 3. A first voltage is measured on the first type of metal line 5 through the circuit between the first pad 1 and the fourth pad 4, and the resistance of the first type of metal line 5 is determined based on the ratio of the first voltage to the first current. However, since the second diode 8 is not conductive at this time, it cannot supply current to the second type of metal line 6, and therefore, the resistance of the second type of metal line 6 cannot be measured.

[0099] In another embodiment, when a negative voltage is applied to the second diode 8, current flows from the negative terminal to the positive terminal of the second diode 8. At this time, a second current can be supplied to the second type of metal line 6 through the circuit between the second pad 2 and the third pad 3, and a second voltage of the second type of metal line 6 can be measured through the circuit between the first pad 1 and the fourth pad 4. The resistance of the second type of metal line 6 is determined based on the ratio of the second voltage to the second current. However, since the first diode 7 is in a non-conducting state at this time, no current can be supplied to the first type of metal line 5, and therefore, the resistance of the first type of metal line 5 cannot be measured.

[0100] Therefore, the resistance of a first type of metal wire can be measured when a positive voltage is applied to the first diode, and the resistance of a second type of metal wire can be measured when a negative voltage is applied to the second diode. This allows for testing of different types of metal wires, avoiding the defect that prevents testing of different types of metal wires when the entire circuit is turned on. It also improves the testing accuracy of testing the resistance of different types of metal wires by reusing a preset number of test pads.

[0101] In an optional embodiment, when a positive or negative voltage is applied to the diode, measuring the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers using the preset number of pads; and obtaining the resistance of the vias connecting different metal layers based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, includes:

[0102] When a positive voltage is applied to the fourth diode 15, a third current is provided to the second via 13 through the circuit between the first pad 1 and the second pad 2, a third voltage of the second via 13 is measured through the circuit between the third pad 3 and the fourth pad 4, and the resistance of the second via 13 is determined based on the ratio of the third voltage to the third current.

[0103] When a negative voltage is applied to the third diode, a fourth current is provided to the first via 12 through the circuit between the first pad 1 and the second pad 2. A fourth voltage is measured on the metal line of the first via 12 through the circuit between the third pad 3 and the fourth pad 4. The resistance of the first via 12 is determined based on the ratio of the fourth voltage to the fourth current.

[0104] In one implementation, continue as follows Figure 4As shown, when a positive voltage is applied to the fourth diode 15, current flows from the positive terminal to the negative terminal of the fourth diode 15, making the fourth diode 15 conductive. This allows a third current to flow through the circuit between the first pad 1 and the second pad 2 to the second via 13, and a third voltage to be measured through the circuit between the third pad 3 and the fourth pad 4. The resistance of the second via 13 is then determined based on the ratio of the third voltage to the third current. However, since the third diode 14 is not conductive at this time, it cannot provide current to the first via 12, and therefore, the resistance of the first via 12 cannot be measured.

[0105] In another embodiment, when a negative voltage is applied to the third diode 14, current flows from the negative terminal to the positive terminal of the third diode 14. At this time, a fourth current can be supplied to the first via 12 through the circuit between the first pad 1 and the second pad 2, and a fourth voltage of the first via 12 can be measured through the circuit between the third pad 3 and the fourth pad 4. The resistance of the first via 12 is determined based on the ratio of the fourth voltage to the fourth current. Since the fourth diode 15 is in a non-conducting state at this time, no current can be supplied to the second via 13, and therefore, the resistance of the second via 13 cannot be measured.

[0106] Therefore, by connecting the second pad 2 to the negative terminal of the third diode 14, the positive terminal of the third diode 14 to the first via 12, the second pad 2 to the positive terminal of the fourth diode 15, and the negative terminal of the fourth diode 15 to the second via 13, the vias connected to different metal layers can be tested during four-terminal testing. This avoids the defect that prevents testing of vias connected to different metal layers when the entire circuit is conducting, and improves the testing accuracy of testing the resistance of vias connected to different metal layers by reusing a preset number of test pads.

[0107] In an optional embodiment, this application also provides a semiconductor structure, the semiconductor structure including a device region and a non-device region, wherein vias or metal lines as described in any of the above embodiments are located in the device region, and a preset number of pads as described in any of the above embodiments are located in the non-device region.

[0108] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0109] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A resistance test structure, characterized by, The resistance testing structure includes: The resistor under test structure includes different types of metal wires or through-holes connecting different metal layers. A preset number of solder pads are provided, and the resistor structure under test is located in the circuit between two adjacent solder pads among the preset number of solder pads. A diode is located in the circuit between the resistor under test structure and the target pad, wherein the target pad is one of the two adjacent thermal pads. The resistance testing structure is used to measure the resistance of different types of metal wires when a positive or negative voltage is applied to the diode, or to measure the resistance of vias connecting different metal layers when a positive or negative voltage is applied to the diode.

2. The resistance test structure of claim 1, wherein, The resistor under test structure includes different types of metal wires, and the preset number of solder pads include a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged in sequence. A circuit for providing current is formed between the second solder pad and the third solder pad, and a circuit for measuring voltage is formed between the first solder pad and the fourth solder pad. The resistor under test is located in the circuit between the second pad and the third pad; The target pad is the second pad, and the diode is disposed in the circuit between the second pad and the different types of metal wires.

3. The resistance test structure of claim 2, wherein, The resistor under test structure includes a first type of metal wire and a second type of metal wire. The diode includes a first diode and a second diode. The first diode is disposed in the circuit between the second pad and the first type of metal wire, and the second diode is disposed in the circuit between the second pad and the second type of metal wire. The positive and negative terminals of the first diode are arranged in opposite directions to those of the second diode.

4. The resistance test structure of claim 3, wherein, The second pad is connected to the positive terminal of the first diode, the negative terminal of the first diode is connected to the first type of metal wire, the second pad is connected to the negative terminal of the second diode, and the positive terminal of the second diode is connected to the second type of metal wire. The resistance test structure is used to provide a first current to the first type of metal line through the circuit between the second and third pads when a positive voltage is applied to the first diode, and to measure a first voltage of the first type of metal line through the circuit between the first and fourth pads, and to determine the resistance of the first type of metal line based on the ratio of the first voltage to the first current. The resistance test structure is used to provide a second current to the second type of metal line through the circuit between the second pad and the third pad when a negative voltage is applied to the second diode, and to measure a second voltage of the second type of metal line through the circuit between the first pad and the fourth pad, and to determine the resistance of the second type of metal line based on the ratio of the second voltage to the second current.

5. The resistance test structure of claim 1, wherein, The resistor under test structure includes through holes connecting different metal layers, and the preset number of solder pads include a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged in sequence. A circuit for providing current is formed between the first solder pad and the second solder pad, and a circuit for measuring voltage is formed between the third solder pad and the fourth solder pad. The resistor under test is located between the second pad and the third pad; The target pad is the second pad, and the diode is disposed in the circuit between the second pad and the via connecting different metal layers.

6. The resistance test structure of claim 5, wherein, The resistor under test structure includes a first through-hole and a second through-hole connecting different metal layers. The diode includes a third diode and a fourth diode. The third diode is disposed in the circuit between the second pad and the first through-hole, and the fourth diode is disposed in the circuit between the second pad and the second through-hole. The positive and negative terminals of the third diode are arranged in opposite directions to those of the fourth diode.

7. The resistance test structure of claim 6, wherein, The second pad is connected to the negative terminal of the third diode, the positive terminal of the third diode is connected to the first through hole, the second pad is connected to the positive terminal of the fourth diode, and the negative terminal of the fourth diode is connected to the second through hole; The resistance test structure is used to provide a third current to the second via through the circuit between the first pad and the second pad when a positive voltage is applied to the fourth diode, and is used to measure a third voltage of the second via through the circuit between the third pad and the fourth pad, and to determine the resistance of the second via based on the ratio of the third voltage to the third current. The resistance test structure is used to provide a fourth current to the first via through the circuit between the first pad and the second pad when a negative voltage is applied to the third diode, and to measure a fourth voltage of the first via through the circuit between the third pad and the fourth pad, and to determine the resistance of the first via based on the ratio of the fourth voltage to the fourth current.

8. A resistance testing method, characterized in that, The resistance testing method is obtained using the resistance testing structure as described in any one of claims 1 to 7, and the resistance testing method includes: When a positive or negative voltage is applied to a diode, the current flowing through different types of metal lines and the voltage on different types of metal lines are measured through a preset number of pads; based on the current flowing through different types of metal lines and the voltage on different types of metal lines, the resistance of different types of metal lines is obtained. Alternatively, when a positive or negative voltage is applied to the diode, the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers are measured through the preset number of pads; based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, the resistance of the vias connecting different metal layers is obtained.

9. The resistance testing method according to claim 8, characterized in that, The preset number of solder pads includes a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged in sequence. A circuit for providing current is formed between the second solder pad and the third solder pad, and a circuit for measuring voltage is formed between the first solder pad and the fourth solder pad. The resistor under test structure includes a first type of metal wire and a second type of metal wire. The diode includes a first diode and a second diode. The first diode is disposed in the circuit between the second solder pad and the first type of metal wire, and the second diode is disposed in the circuit between the second solder pad and the second type of metal wire. When a positive or negative voltage is applied to the diode, the current flowing through different types of metal lines and the voltage on different types of metal lines are measured by a preset number of pads. Based on the current flowing through different types of metal wires and the voltage across those wires, the resistance of different types of metal wires can be determined, including: When a forward voltage is applied to the first diode, a first current is provided to the first type of metal line through the circuit between the second and third pads, a first voltage of the first type of metal line is measured through the circuit between the first and fourth pads, and the resistance of the first type of metal line is determined based on the ratio of the first voltage to the first current. When a negative voltage is applied to the second diode, a second current is provided to the first type of metal line through the circuit between the second and third pads, a second voltage of the second type of metal line is measured through the circuit between the first and fourth pads, and the resistance of the second type of metal line is determined based on the ratio of the second voltage to the second current.

10. The resistance testing method according to claim 8, characterized in that, The preset number of solder pads includes a first solder pad, a second solder pad, a third solder pad, and a fourth solder pad arranged in sequence. A circuit for providing current is formed between the first solder pad and the second solder pad, and a circuit for measuring voltage is formed between the third solder pad and the fourth solder pad. The resistor under test structure includes a first through-hole and a second through-hole connecting different metal layers. The diode includes a third diode and a fourth diode. The third diode is disposed in the circuit between the second solder pad and the first through-hole, and the fourth diode is disposed in the circuit between the second solder pad and the second through-hole. When a positive or negative voltage is applied to the diode, the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers are measured through the preset number of pads; based on the current flowing through the vias connecting different metal layers and the voltage of the vias connecting different metal layers, the resistance of the vias connecting different metal layers is obtained, including: When a forward voltage is applied to the fourth diode, a third current is provided to the second via through the circuit between the first and second pads, a third voltage of the second via is measured through the circuit between the third and fourth pads, and the resistance of the second via is determined based on the ratio of the third voltage to the third current. When a negative voltage is applied to the third diode, a fourth current is provided to the first via through the circuit between the first pad and the second pad, a fourth voltage is measured on the metal line of the first via through the circuit between the third pad and the fourth pad, and the resistance of the first via is determined based on the ratio of the fourth voltage to the fourth current.

11. A semiconductor structure, characterized in that, The semiconductor structure includes a device region and a non-device region, wherein a via or metal line as described in any one of claims 1 to 10 is located in the device region, and a predetermined number of pads as described in any one of claims 1 to 10 are located in the non-device region.

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