CN117630529A - Electromigration test structure and test device - Google Patents

Abstract

The invention discloses an electromigration test structure and a test device. The electromigration test structure is used for inputting two or more test currents in parallel by arranging at least two groups of test current detection ends at two ends of the structure to be tested, and arranging voltage detection ends at two ends of the structure to be tested to detect the voltage at two ends of the structure to be tested, so that the current flowing on a single probe card is reduced when the test current is input, the maximum test current of the electromigration test structure is increased, and the test efficiency of the electromigration test is improved.

Description

Electromigration test structure and test device

Technical Field

The invention relates to the technical field of semiconductors, in particular to an electromigration test structure and a test device.

Background

With the continued development of semiconductor technology, the integration of integrated circuits has increased and the size and pitch of devices has been reduced, which has made the reliability of metal interconnect lines within devices increasingly important, wherein electromigration (EM, electro Migration) reliability is an important part of the reliability of metal interconnect lines. Electromigration refers to a metal migration phenomenon generated by a metal interconnection line under the action of current and temperature, and when moving electrons and a main metal lattice exchange momentum, metal atoms migrate along the electron flow direction, cavities are formed at original positions, and hillock-shaped protrusions are formed by migration and accumulation of the metal atoms, so that the metal interconnection line is opened or broken or is difficult to photoetching and short-circuited between layers, and the reliability of a semiconductor device is affected. Electromigration is a microscopic phenomenon, and is firstly shown as resistance increase under the condition that the electromigration is not obvious, the electromigration can be predicted to occur by measuring the resistance of the metal interconnection line, and the electromigration is shown to seriously influence the normal operation of the component when the resistance is suddenly increased.

In the conventional electromigration detection structure, the resistance value of the metal interconnection line is usually detected by adopting a Kelvin four-terminal method, and the resistance value of the interconnection line to be detected is obtained by applying a test current to two ends of the interconnection line to be detected and obtaining the voltage values of the two ends of the interconnection line to be detected. However, since the probe card is required to be in contact with the current input port when the test current is applied, and since the metal interconnection line has small resistance, a larger test current is required to be applied to heat the interconnection line to be tested to a required temperature, when the test current is larger than the maximum current limit, the probe card can generate melting due to excessive heating of the current, and the test cannot be continued, so that the electromigration detection structure has limited use field, and when the test current is larger, the electromigration detection cannot be performed.

Disclosure of Invention

In the summary, a series of concepts in a simplified form are introduced, which will be further described in detail in the detailed description. The summary of the invention is not intended to define the key features and essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In order to solve the problems in the prior art, the invention provides an electromigration test structure, which at least comprises a structure to be tested, a first current input end, a first current output end, a second current input end, a second current output end, a first voltage detection end and a second voltage detection end, wherein: the first current input end, the second current input end and the first voltage detection end are all connected with the first end of the structure to be detected; the first current output end, the second current output end and the second voltage detection end are all connected with the second end of the structure to be detected.

Illustratively, the first current input includes a first pad, the first current output includes a second pad, the second current input includes a third pad, and the second current output includes a fourth pad.

Illustratively, the first voltage detection terminal includes a first voltage detection pad and the second voltage detection terminal includes a second voltage detection pad.

Illustratively, the structure under test includes a metal interconnect line in a semiconductor device.

Illustratively, the test currents input by the first current input and the second current input are equal.

According to another aspect of the present application, there is further provided an electromigration test apparatus for testing an electromigration test structure, where the electromigration test structure at least includes a structure to be tested, a first current input end, a first current output end, a second current input end, a second current output end, a first voltage detection end, and a second voltage detection end, where the first current input end, the second current input end, and the first voltage detection end are all connected to the first end of the structure to be tested; the first current output end, the second current output end and the second voltage detection end are all connected with the second end of the structure to be detected;

the electromigration test device at least comprises a first test current branch and a second test current branch, wherein a first end of the first test current branch is electrically connected with the first current input end, and a second end of the first test current branch is electrically connected with the first current output end; the first end of the second test current branch is electrically connected with the second current input end, and the second end of the second test current branch is electrically connected with the second current output end.

Illustratively, the first current input terminal includes a first pad, the first current output terminal includes a second pad, the second current input terminal includes a third pad, and the second current output terminal includes a fourth pad; the first end of the first test current branch comprises a first probe card for contacting the first welding pad; the second end of the first test current branch comprises a second probe card which is used for being contacted with the second welding pad, and the first probe card and the second probe card provide a first test current for the structure to be tested; the first end of the second test current branch comprises a third probe card for contacting with the third welding pad; and the second end of the second test current branch comprises a fourth probe card for contacting with the fourth welding pad, and the third probe card and the fourth probe card provide a second test current for the structure to be tested.

Illustratively, the test currents output by the first and second test current branches are equal.

According to another aspect of the present application, there is further provided an electromigration test apparatus for testing an electromigration test structure, where the electromigration test structure at least includes a structure to be tested, a first current input end, a first current output end, a first voltage detection end, and a second voltage detection end, where the first current input end and the first voltage detection end are both connected to the first end of the structure to be tested; the first current output end and the second voltage detection end are both connected with the second end of the structure to be detected; the electromigration test device at least comprises a first test current branch and a second test current branch, wherein the first end of the first test current branch and the first end of the second test current branch are electrically connected with the first current input end, and the second end of the first test current branch and the second end of the second test current branch are electrically connected with the first current output end.

Illustratively, the first current input terminal includes a first pad and the first current output terminal includes a second pad; the first end of the first test current branch comprises a first probe card, the second end of the first test current branch comprises a second probe card, and the first probe card and the second probe card provide a first test current to the structure to be tested; the first end of the second test current branch comprises a third probe card, the second end of the second test current branch comprises a fourth probe card, and the third probe card and the fourth probe card provide a second test current for the structure to be tested.

Illustratively, the first and third probe cards are spaced apart a predetermined distance to simultaneously contact the first pads, and the second and fourth probe cards are spaced apart a predetermined distance to simultaneously contact the second pads.

Illustratively, the test currents output by the first and second test current branches are equal.

According to the electromigration test structure, at least two groups of test current detection ends are arranged at two ends of the structure to be tested and used for inputting two or more test currents in parallel, and voltage detection ends are arranged at two ends of the structure to be tested to detect voltages at two ends of the structure to be tested, so that current flowing on a single probe card is reduced when the test currents are input, the maximum test current of the electromigration test structure is increased, and the test efficiency of the electromigration test is improved.

Drawings

The foregoing and other objects, features and advantages of the present application will become more apparent from the following more particular description of embodiments of the present application, as illustrated in the accompanying drawings. The accompanying drawings are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate the application and not constitute a limitation to the application. In the drawings, like reference numerals generally refer to like parts or steps.

FIG. 1 shows a schematic circuit diagram of an electromigration test using a conventional electromigration test architecture;

FIG. 2 shows a schematic structural diagram of a conventional electromigration test structure;

FIG. 3 illustrates a schematic structural diagram of an electromigration test structure in accordance with an embodiment of the present application;

FIG. 4 shows a schematic diagram of an electromigration test apparatus using an embodiment in accordance with the present application;

fig. 5 shows a schematic diagram using an electromigration test apparatus according to another embodiment of the present application.

Detailed Description

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size of layers and regions, as well as the relative sizes, may be exaggerated for clarity. Like numbers refer to like elements throughout.

It will be understood that when an element or layer is referred to as being "on" …, "adjacent to" …, "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected to or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on" …, "directly adjacent to" …, "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

Spatially relative terms, such as "under …", "below" … "," beneath "," under … "," above … "," above "and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, then elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "under …" and "under …" may include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present specification and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

In order to provide a thorough understanding of the present invention, detailed steps and structures will be presented in the following description in order to illustrate the technical solution presented by the present invention. Preferred embodiments of the present invention are described in detail below, however, the present invention may have other embodiments in addition to these detailed descriptions.

Electromigration refers to a phenomenon that electrons in a metal interconnect line undergo electron migration under the action of a large current. When electrons flow through the wire, they collide with atoms of the wire, which causes an increase in resistance of the metal and heat generation. If a large number of electrons collide with metal atoms within a certain period of time, the metal atoms flow in the direction of the electrons. This will result in the moved atoms leaving a void in the metal, and if a large number of atoms are moved, the wire will break; further, the moving atoms stop at a certain place, and a large amount of accumulation is formed at the end of the current flow direction. Taking copper wire as an example, the skin effect of the current causes electrons to move across the surface of the copper wire. After collision, atoms on the surface are continuously impacted to move towards the end of the wire. The copper wires at the places where atoms leave are continuously thinned and even broken, and the copper wires at the places where atoms are accumulated are continuously thickened and even possibly contact with surrounding metal wires to cause short circuits. In order to detect whether or not a metal interconnect in a semiconductor device has degraded performance, disconnected, and/or shorted due to electromigration failure, electromigration testing of the metal interconnect is required.

In the current electromigration test structure, as shown in fig. 1, a kelvin four-terminal method is generally used to detect the resistance value of the structure to be tested. Since the structure to be measured is usually a metal interconnect in a semiconductor device, the resistance value thereof is usually low, and if the structure to be measured is directly connected to an ohmmeter, the resistance value of a wire between the structure to be measured and the ohmmeter will cause a serious measurement error, so that the structure to be measured is subjected to electromigration test by adopting the kelvin four-terminal method as shown in fig. 1. As shown in the circuit diagram of fig. 1, voltmeter 102 is connected in parallel to two ends of structure under test 101, and test current branches are arranged at two ends of structure under test 101, and each test current branch comprises a power supply 103 and an ammeter 104.

In the process of testing using the circuit shown in fig. 1, the voltmeter 102 measures the voltage V of the structure 101 to be tested, and the ammeter 104 measures the current I of the structure 101 to be tested, which can be calculated, where the resistance r=v/I of the structure to be tested. In the test structure shown in fig. 1, the voltage drop on the wires connected to both ends of the voltmeter 102 at both ends of the structure under test 101 is negligible with respect to the voltage drop at both ends of the structure under test 101, so that measurement errors introduced by wire resistance can be avoided. In the electromigration test process, it is generally required to continuously measure a structure to be tested for a period of time, continuously record a measured current value, a measured voltage value and a calculated resistance value, and judge the electromigration reliability of the structure to be tested according to a measurement result.

In the electromigration test structure 200 shown in fig. 2, a current input terminal 202a and a voltage test input terminal 203a are connected to a first terminal of the structure under test 101, and a current output terminal 202b and a voltage test output terminal 203b are connected to a second terminal of the structure under test 101. The positive pole of the power supply 103 in the test circuit 100 is connected with the current input end 202a on the test structure 200, the output end of the ammeter 104 is connected with the current output end 202b on the test structure 200, the input end of the voltmeter 102 is connected with the voltage test input end 203a, and the output end of the voltmeter 102 is connected with the voltage test output end 203b. Wherein the electrical connection between the devices in test circuit 100 and the devices on test structure 101 is made by the contact of the probe card disposed on test structure 100 with the bond pads disposed on each connection port on test structure 200. Due to the material and dimensional factors of the metal probes of the probe card disposed on the test structure 100, melting of the probe card will occur when the current flowing through the probe card exceeds a certain threshold. When the test structure shown in fig. 1 is used for testing the metal interconnection line of the semiconductor device, a relatively large test current needs to be applied to the test current branch because of relatively low resistance of the metal interconnection line, and the test current flows through the probe card, when the test current is greater than the current threshold of the probe card, the probe card generates heat to reduce the performance, and finally a melting phenomenon occurs to prevent the test.

An electromigration test structure according to an embodiment of the present application is described below with reference to fig. 3 and 4, wherein fig. 3 shows a schematic structural diagram of the electromigration test structure according to an embodiment of the present application, and fig. 4 shows a schematic diagram using an electromigration test apparatus according to an embodiment of the present application.

In order to at least partially solve the foregoing technical problem, as shown in fig. 3, the present application provides an electromigration test structure 300, at least including a structure under test 301, a first current input terminal 302a, a first current output terminal 302b, a second current input terminal 303a, a second current output terminal 303b, a first voltage detection terminal 304a and a second voltage detection terminal 304b, wherein: the first current input end 302a, the second current input end 303a and the first voltage detection end 304a are all connected to the first end of the structure 301 to be tested; the first current output end 302b, the second current output end 303b and the second voltage detection end 304b are all connected to the second end of the structure under test 301.

According to the electromigration test structure, at least two groups of test current detection ends are arranged at two ends of the structure to be tested and used for inputting two or more test currents in parallel, and then the voltage detection ends are arranged at two ends of the structure to be tested so as to detect the voltage at two ends of the structure to be tested, so that the current flowing through a single probe card is reduced when the test current is input, the maximum test current of the electromigration test structure is increased, and the test efficiency of the electromigration test is improved.

Illustratively, the first current input includes a first bond pad, the first current output includes a second bond pad, the second current input includes a third bond pad, and the second current output includes a fourth bond pad. In one example, as shown in fig. 3, each end on the electromigration test structure 300 is a pad, wherein the first current input 302a includes a first pad, the first current output 302b includes a second pad, the second current input 303a includes a third pad, and the second current output 303b includes a fourth pad.

Illustratively, the first voltage detection terminal includes a first voltage detection pad and the second voltage detection terminal includes a second voltage detection pad. In one example, as shown in fig. 3, the first voltage detection terminal 304a and the second voltage detection terminal 304b on the electromigration test structure 300 are both pads.

Illustratively, the structure under test includes metal interconnect lines in a semiconductor device. In one example, connecting the metal interconnect lines in the semiconductor device to the test structure may be used to perform electromigration test on the metal interconnect lines in the semiconductor device by a test station to test electromigration reliability of the metal interconnect lines of the semiconductor device.

Illustratively, the test currents input by the first current input and the second current input are equal. In one example, the first test current I1 input at the first current input terminal 302a and the second test current I2 input at the second current input terminal 303a are equal as shown in fig. 3. In one example, when two or more current inputs are included on electromigration test structure 300, the test currents input by the two or more current inputs are all equal.

According to another aspect of the present application, as shown in fig. 4, there is further provided an electromigration test apparatus 400 for testing an electromigration test structure 300, where the electromigration test structure 300 at least includes a structure under test 301, a first current input 302a, a first current output 302b, a second current input 303a, a second current output 303b, a first voltage detection 304a, and a second voltage detection 304b, and the first current input 302a, the second current input 303a, and the first voltage detection 304a are all connected to a first end of the structure under test 301; the first current output end 302b, the second current output end 303b and the second voltage detection end 304b are all connected with the second end of the structure 301 to be tested; the electromigration test apparatus 400 at least comprises a first test current branch 402 and a second test current branch 403, wherein a first end 402a of the first test current branch 402 is electrically connected to the first current input end 302a, and a second end 402b of the first test current branch 402 is electrically connected to the first current output end 302b; the first end 403a of the second test current branch 403 is electrically connected to the second current input end 303a, and the second end 403b of the second test current branch 403 is electrically connected to the second current output end 303b.

In one example, as shown in fig. 4, the test apparatus 400 further includes a voltage detection branch, a first end 404a of the voltage detection branch being connected to the first voltage detection end 304a of the electromigration test 300, and a second end 404b of the voltage detection branch being connected to the second voltage detection end 304b.

Illustratively, the first current input terminal includes a first pad, the first current output terminal includes a second pad, the second current input terminal includes a third pad, and the second current output terminal includes a fourth pad; the first end of the first test current branch comprises a first probe card for contacting the first welding pad; the second end of the first test current branch comprises a second probe card which is used for being contacted with the second welding pad, and the first probe card and the second probe card provide a first test current for the structure to be tested; the first end of the second test current branch comprises a third probe card for contacting with the third welding pad; and the second end of the second test current branch comprises a fourth probe card for contacting with the fourth welding pad, and the third probe card and the fourth probe card provide a second test current for the structure to be tested.

As shown in fig. 4, in one example, when the test apparatus 400 of fig. 4 is used to perform an electromigration test on the structure 301 under test, the first end 402a of the first test current leg 402 includes a first probe card, the second end 402b of the first test current leg includes a second probe card, the first end 403a of the second test current leg 403 includes a third probe card, and the second end 403b of the second test current leg 403 includes a fourth probe card. As shown in fig. 4, the first test current branch 402 is electrically connected to the test structure 300 through the first end 402a of the first test current branch 402 and the second end 402b of the first test current branch 402 to provide the first test current I1 to the structure under test 301, i.e. the first probe card is in contact with the first pad and the second probe card is in contact with the second pad; the second test current branch 403 is electrically connected to the test structure 300 through the first end 403a of the second test current branch 403 and the second end 403b of the second test current branch 403 to provide the second test current I2 to the structure under test 301, i.e. the third probe card is in contact with the third pad and the fourth probe card is in contact with the fourth pad. In one example, a first power supply and a first current detection unit are included in the first test current leg 402 and a second power supply and a second current detection unit are included in the second test current leg 403. The first power supply is used for supplying power to the structure 301 to be tested, and the first current detection unit is used for obtaining a current value of a first test current I1; the second power supply is used for supplying power to the structure to be tested 301, and the second current detection unit is used for obtaining a current value of the second test current I2.

Limited by the material and size of the probe card, the maximum current that can be passed on a single probe card is Imax, I1 is less than or equal to Imax and I2 is less than or equal to Imax, so the current I that can be passed on the structure to be tested is less than or equal to 2 x Imax.

Illustratively, the test currents output by the first test current branch and the second test current branch are equal. In one example, the first test current and the second test current are equal, i.e., i1=i2.

In one example, the test structure further comprises: one or more current input terminals connected to the first end of the structure to be tested; one or more current output terminals connected to the second end of the structure under test. In one example, the test device may connect the test structure to two or more test current branches to apply two or more test currents to the structure to be tested, which may further reduce the current of a single test current branch, so that the current flowing on a single probe card is reduced, and thus the maximum value of the test current passing on the structure to be tested is further increased without changing the material of the probe card.

In one example, as shown in fig. 4, the two ends of the structure under test 301 are connected in parallel with a voltage detection branch, the first voltage detection end 304a is connected to the first end 404a of the voltage detection branch, and the second voltage detection end 304b is connected to the second end 404b of the voltage detection branch. In one example, the first end 404a of the voltage detection branch includes a first voltage probe card for contacting the first voltage detection pad, and the second end 404b of the voltage detection branch includes a second voltage probe card for contacting the second voltage detection pad, the first voltage probe card and the second voltage probe card being configured to obtain a detection voltage across the structure under test.

In one example, the first voltage detection pad is in contact with the first voltage probe card, and the second voltage detection pad is in contact with the second voltage probe card, so that the voltage detection branch is connected in parallel to two ends of the structure 301 to be tested, and the voltage detection branch comprises a voltmeter, so that the voltage of two ends of the structure 301 to be tested can be measured.

According to another aspect of the present application, as shown in fig. 5, there is further provided an electromigration test apparatus 500 for testing an electromigration test structure 300, where the electromigration test structure 300 at least includes a structure under test 301, a first current input 302a, a first current output 302b, a first voltage detection 304a and a second voltage detection 304b, and the first current input 302a and the first voltage detection 304a are both connected to a first end of the structure under test 301; the first current output end 302b and the second voltage detection end 304b are both connected to the second end of the structure 301 to be tested;

the electromigration test apparatus 500 at least comprises a first test current branch 502 and a second test current branch 503, wherein a first end 502a of the first test current branch 502 and a first end 503a of the second test current branch 503 are electrically connected to the first current input end 302a, and a second end 502b of the first test current branch 502 and a second end 503b of the second test current branch 503 are electrically connected to the first current output end 302b.

Illustratively, the first current input comprises a first pad and the first current output comprises a second pad; the first end of the first test current branch comprises a first probe card, the second end of the first test current branch comprises a second probe card, and the first probe card and the second probe card provide a first test current for a structure to be tested; the first end of the second test current branch comprises a third probe card, the second end of the second test current branch comprises a fourth probe card, and the third probe card and the fourth probe card provide the second test current for the structure to be tested.

Illustratively, the first and third probe cards are spaced apart a predetermined distance to simultaneously contact the first pads, and the second and fourth probe cards are spaced apart a predetermined distance to simultaneously contact the second pads.

As shown in fig. 5, in one example, when the test apparatus 500 of fig. 5 is used to perform an electromigration test on the structure 301 under test, the first end 502a of the first test current leg 502 includes a first probe card, the second end 502b of the first test current leg includes a second probe card, the first end 503a of the second test current leg 503 includes a third probe card, and the second end 503b of the second test current leg 503 includes a fourth probe card. As shown in fig. 5, the first test current branch 502 is electrically connected to the test structure 300 through a first end 502a of the first test current branch 502 and a second end 502b of the first test current branch 502 to provide a first test current I1 to the structure under test 301; the second test current branch 503 is electrically connected to the test structure 300 through the first end 503a of the second test current branch 503 and the second end 503b of the second test current branch 503 to provide the second test current I2 to the structure under test 301, that is, the first probe card and the third probe card are separated by a predetermined distance D to simultaneously contact the first pad; the second probe card and the fourth probe card are spaced apart by a predetermined distance D to simultaneously contact the second pads. In one example, a first power supply and a first current detection unit are included in the first test current branch 502, and a second power supply and a second current detection unit are included in the second test current branch 503. The first power supply is used for supplying power to the structure 301 to be tested, and the first current detection unit is used for obtaining a current value of a first test current I1; the second power supply is used for supplying power to the structure to be tested 301, and the second current detection unit is used for obtaining a current value of the second test current I2. In one example, the preset distance D is determined by the probe card material, the magnitude of the first test current, and the magnitude of the second test current.

Limited by the material and size of the probe card, the maximum current that can be passed on a single probe card is Imax, I1 is less than or equal to Imax and I2 is less than or equal to Imax, so the current I that can be passed on the structure to be tested is less than or equal to 2 x Imax.

Illustratively, the test currents output by the first test current branch and the second test current branch are equal. In one example, the first test current and the second test current are equal, i.e., i1=i2.

In one example, the test structure further comprises: one or more current input terminals connected to the first end of the structure to be tested; one or more current output terminals connected to the second end of the structure under test. In one example, the test device may connect the test structure to two or more test current branches to apply two or more test currents to the structure to be tested, which may further reduce the current of a single test current branch, so that the current flowing on a single probe card is reduced, and thus the maximum value of the test current passing on the structure to be tested is further increased without changing the material of the probe card.

In one example, as shown in fig. 5, voltage detection branches are connected in parallel to two ends of the structure under test 301, and referring to fig. 3, a first voltage detection end 304a is connected to a first end 504a of the voltage detection branch, and a second voltage detection end 304b is connected to a second end 504b of the voltage detection branch. In one example, the first end 504a of the voltage detection branch includes a first voltage probe card for contacting a first voltage detection pad, and the second end 504b of the voltage detection branch includes a second voltage probe card for contacting a second voltage detection pad, the first voltage probe card and the second voltage probe card being configured to obtain a detection voltage across the structure under test.

In one example, the first voltage detection pad is in contact with the first voltage probe card, and the second voltage detection pad is in contact with the second voltage probe card, so that the voltage detection branch is connected in parallel to two ends of the structure 301 to be tested, and the voltage detection branch comprises a voltmeter, so that the voltage of two ends of the structure 301 to be tested can be measured.

According to the electromigration test structure, at least two groups of test current detection ends are arranged at two ends of the structure to be tested and used for inputting two or more test currents in parallel, and voltage detection ends are arranged at two ends of the structure to be tested to detect voltages at two ends of the structure to be tested, so that current flowing on a single probe card is reduced when the test currents are input, the maximum test current of the electromigration test structure is increased, and the test efficiency of the electromigration test is improved.

It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order. These words may be interpreted as names.

The above description is merely illustrative of specific embodiments of the present application or the descriptions of specific embodiments, the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes or substitutions are covered in the protection scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims (12)

1. The electromigration test structure is characterized by at least comprising a structure to be tested, a first current input end, a first current output end, a second current input end, a second current output end, a first voltage detection end and a second voltage detection end, wherein:

the first current input end, the second current input end and the first voltage detection end are all connected with the first end of the structure to be detected;

the first current output end, the second current output end and the second voltage detection end are all connected with the second end of the structure to be detected.

2. The test structure of claim 1, wherein the first current input comprises a first pad, the first current output comprises a second pad, the second current input comprises a third pad, and the second current output comprises a fourth pad.

3. The test structure of claim 1, wherein the first voltage sense terminal comprises a first voltage sense pad and the second voltage sense terminal comprises a second voltage sense pad.

4. The test structure of claim 1, wherein the structure under test comprises a metal interconnect line in a semiconductor device.

5. The test structure of claim 1, wherein the test currents input by the first current input and the second current input are equal.

6. An electromigration test device is used for testing an electromigration test structure and at least comprises a structure to be tested, a first current input end, a first current output end, a second current input end, a second current output end, a first voltage detection end and a second voltage detection end, wherein the first current input end, the second current input end and the first voltage detection end are all connected with the first end of the structure to be tested; the first current output end, the second current output end and the second voltage detection end are all connected with the second end of the structure to be detected; it is characterized in that the method comprises the steps of,

the electromigration test device at least comprises a first test current branch and a second test current branch, wherein a first end of the first test current branch is electrically connected with the first current input end, and a second end of the first test current branch is electrically connected with the first current output end; the first end of the second test current branch is electrically connected with the second current input end, and the second end of the second test current branch is electrically connected with the second current output end.

7. The test device of claim 6, wherein the first current input comprises a first pad, the first current output comprises a second pad, the second current input comprises a third pad, and the second current output comprises a fourth pad; the first end of the first test current branch comprises a first probe card for contacting the first welding pad; and

the second end of the first test current branch comprises a second probe card which is used for being contacted with the second welding pad, and the first probe card and the second probe card are used for providing a first test current for the structure to be tested;

the first end of the second test current branch comprises a third probe card for contacting with the third welding pad; and

the second end of the second test current branch comprises a fourth probe card for contacting with the fourth welding pad, and the third probe card and the fourth probe card provide a second test current for the structure to be tested.

8. The test device of claim 6, wherein the test currents output by the first and second test current branches are equal.

9. An electromigration test device is used for testing an electromigration test structure and at least comprises a structure to be tested, a first current input end, a first current output end, a first voltage detection end and a second voltage detection end, wherein the first current input end and the first voltage detection end are both connected with the first end of the structure to be tested; the first current output end and the second voltage detection end are both connected with the second end of the structure to be detected; it is characterized in that the method comprises the steps of,

the electromigration test device at least comprises a first test current branch and a second test current branch, wherein the first end of the first test current branch and the first end of the second test current branch are electrically connected with the first current input end, and the second end of the first test current branch and the second end of the second test current branch are electrically connected with the first current output end.

10. The test device of claim 9, wherein the first current input comprises a first pad and the first current output comprises a second pad; the first end of the first test current branch comprises a first probe card, the second end of the first test current branch comprises a second probe card, and the first probe card and the second probe card provide a first test current to the structure to be tested; the first end of the second test current branch comprises a third probe card, the second end of the second test current branch comprises a fourth probe card, and the third probe card and the fourth probe card provide a second test current for the structure to be tested.

11. The test apparatus of claim 10, wherein the first probe card and the third probe card are spaced apart a predetermined distance to simultaneously contact the first bond pad, and the second probe card and the fourth probe card are spaced apart a predetermined distance to simultaneously contact the second bond pad.

12. The test device of claim 9, wherein the test currents output by the first and second test current branches are equal.