EP1516195A1 - Elektromigrations-testvorrichtung und elektromigrations-testverfahren - Google Patents
Elektromigrations-testvorrichtung und elektromigrations-testverfahrenInfo
- Publication number
- EP1516195A1 EP1516195A1 EP03740110A EP03740110A EP1516195A1 EP 1516195 A1 EP1516195 A1 EP 1516195A1 EP 03740110 A EP03740110 A EP 03740110A EP 03740110 A EP03740110 A EP 03740110A EP 1516195 A1 EP1516195 A1 EP 1516195A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- conductive structure
- tested
- electromigration
- current
- test
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/2851—Testing of integrated circuits [IC]
- G01R31/2855—Environmental, reliability or burn-in testing
- G01R31/2856—Internal circuit aspects, e.g. built-in test features; Test chips; Measuring material aspects, e.g. electro migration [EM]
- G01R31/2858—Measuring of material aspects, e.g. electro-migration [EM], hot carrier injection
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2648—Characterising semiconductor materials
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/2851—Testing of integrated circuits [IC]
- G01R31/2853—Electrical testing of internal connections or -isolation, e.g. latch-up or chip-to-lead connections
Definitions
- the invention relates to an electromigration test device and an electromigration test method.
- Electromigration is understood to mean the transport of materials within a conductor track under the influence of the electrical current. The material transport takes place in the direction of the flow of electrons. These entrain the lattice atoms of the conductor material due to the so-called electron wind. This material transport can lead to various types of damage. Damage is, for example, so-called voids, i.e. Gaps within the lattice structure, and resulting breaks in the conductor track. Another example are so-called extrusions, i.e. lateral outflows of conductor material from the actual conductor. These extrusions can lead to short circuits between adjacent conductor tracks and thus to the failure of the component.
- the size of electromigration is a parameter that determines the lifespan of the electronic component.
- the strength of the electromigration process depends primarily on the material of the conductor track, the temperature and the electrical current density in the conductor track, the degree of electromigration increasing with increasing temperature and increasing electrical current density.
- the DC component of electrical current density is crucial.
- a symmetrical alternating current hardly influences the strength of the electromigration. Electromigration, which is caused by a symmetrical alternating current, occurs 100 to 1000 times slower than electromigration, which is caused by a direct current [1]. It follows from this that, when an alternating current and a direct current are superimposed, the magnitude of the electromigration is dominated by the electrical current density which is produced by means of the direct current. This can be clearly explained by the fact that the so-called electron wind must have a preferred direction so that it can effectively carry the material of the conductive structure with it in one direction. However, a symmetrical alternating current has no such preferred direction of the electron wind.
- test structures are generally produced together with the actual components on the same substrate and from the same materials as the components.
- the test structures are therefore subject to the same manufacturing processes and can be used to assess the electromigration strength of similar conductor tracks in the end product.
- test structures e.g. metal conductor tracks
- the ceramic housings are put on circuit boards.
- the boards are then arranged in a measuring setup and, placed in a suitable heating furnace, subjected to electromigration tests.
- the test structures are exposed to a constant direct current.
- damage which can be caused by electromigration is, for example, the formation of so-called voids, ie gaps within the lattice structure and resulting interruptions in the conductive structure, for example conductor tracks of an integrated circuit.
- voids ie gaps within the lattice structure and resulting interruptions in the conductive structure, for example conductor tracks of an integrated circuit.
- a simple conductor track with its corresponding connections is used, for example.
- the conductor track is placed under stress, ie increased temperature and increased current density.
- the time that elapses before the test structure fails is measured. This time provides a measure of the strength of the electromigration processes that a component was subject to.
- the average life can 'of the structure is calculated under normal operating conditions.
- a further damage which can be caused by electromigration is, for example, the occurrence of so-called extrusions, ie an outflow of material from the conductor track under the influence of electromigration.
- the extrusions can short circuit and thus lead to the failure of an electronic circuit located on the wafer.
- test structures i.e. Conductive structures, whose susceptibility to electromigration is to be investigated, first have to be prepared for the test.
- the test structures are stated and then reassembled in a test device.
- These steps are both labor intensive and time consuming and therefore costly.
- the boards used for the test device must also be heat-resistant. This means that the temperature can only be increased to around 400 ° C, since there are no boards that can withstand a higher temperature without damage. Only a few boards are available for these temperatures, which can withstand this temperature for a long time. This means that temperatures of more than 350 ° C cannot be handled industrially.
- the stress in other words, the load that can be imposed on the test structure is limited by the limited temperature and thus the tests take a long time until a reliable statement about the extent of electromigration in the test structure can be made.
- test structures are also known in the prior art. With these test structures exploited that the test structures by means of the direct current, which serves as a stress source for the test structure, heats up because of the ohmic resistance of the conductive structure to be tested. This means that an external heating furnace can be omitted in a self-heating test structure.
- J.A. Maiz examines the effect of an asymmetrical current on electromigration. The result is that the equivalent direct current of an asymmetrical current is given by the mean value of the current of the signal.
- the invention is based on the problem of providing a simple test device by means of which the temperature can be regulated without an external oven.
- the test structure should not undesirably couple the two high temperatures and electrical current density, as occurs in a self-heating test structure according to the prior art.
- An electromigration test device has a direct current source and an alternating current source. Furthermore, the test device has a circuit. This has at least one conductive structure to be tested, which is electrically conductively connected to the direct current source and the alternating current source. Furthermore, the test device has a measuring device that is set up in such a way that it detects an electrical parameter, which parameter is indicative of electromigration in the test structure.
- the alternating voltage source is set up in such a way that it exposes the conductive structure to be tested to an alternating current, independently of a direct current from the direct current source.
- the conductive structure to be tested is heated to a predetermined, preferably adjustable, temperature.
- a method according to the invention for testing a conductive structure for electromigration has the following steps.
- a conductive structure to be tested is electrically coupled to an electrical circuit, which electrical circuit is electrically coupled to a direct current source and an alternating current source.
- the conductive structure to be tested becomes exposed to a direct electrical current, which direct current causes the electromigration within the conductive structure to be tested.
- the method according to the invention has a heating of the conductive structure to be tested by means of an alternating current generated by the alternating voltage source, the alternating current being independent of the direct current which causes the electromigration within the conductive structure to be tested.
- the method according to the invention has the step of detecting an electrical parameter, which parameter is indicative of the electromigration within the conductive structure to be tested.
- a simple test device is provided by means of the device and the method, by means of which the temperature is regulated without using an external oven. This avoids the undesired coupling of the two high temperatures and electrical current density, as occurs in a self-heating test structure according to the prior art.
- the preferably symmetrical, alternating electrical current which is used to heat the conductive structure to be tested, does not itself cause electromigration in the structure to be tested.
- the temperature to which the structure to be tested is exposed can be increased to significantly more than 400 ° C., since only the electrically conductive structure to be examined is heated in the device and the method.
- the circuit board itself is not exposed to an elevated temperature. This also eliminates the problems and restrictions (e.g. heat resistance) that occur with test structures according to the prior art when selecting the boards.
- Another advantage of the device according to the invention over a device according to the prior art is that the fact that the temperature can be brought to higher values means that the individual tests of the conductive structures to be tested can be carried out in a shorter time.
- investigations of electromigration in periods in the range of minutes are possible, preferably in a period of 10 minutes to 100 minutes.
- the short time span enables the tests to be carried out directly on the wafer level. This leads to a further cost saving, since the above-mentioned extensive actions for preparing the conductive structure to be tested are omitted.
- the electromigration test device according to the invention is described in more detail below. Refinements of the electromigration test device also apply to the method for testing a conductive structure for electromigration.
- the electrically conductive parameter is preferably an electrical resistance of the conductive structure to be tested.
- the electromigration test device preferably also has an evaluation unit for determining an electrical power.
- the evaluation unit preferably has a voltage measuring device and a current measuring device.
- the voltage measuring device and the current measuring device are introduced into the circuit in such a way that the current measuring device generates an effective electrical current which is passed through the conductive conductor to be tested Structure flows, measures, and that the voltage measuring device detects an effective electrical voltage which is applied to the conductive structure to be tested.
- the conductive structure to be tested preferably consists of aluminum, copper or an alloy of copper and aluminum or other electrically conductive materials such as gold or silver.
- the test device according to the invention also preferably has a control device.
- the control device is set up in such a way that it controls and / or regulates the AC voltage source in such a way that the temperature of the conductive structure to be tested is set and kept constant at a predetermined level.
- At least some of the components of the test device according to the invention are preferably arranged on a semiconductor wafer.
- the alternating current source is preferably integrated in a pulse generator.
- the DC voltage source is preferably also integrated in the pulse generator. That the pulse generator is preferably designed as an AC power source provided with an offset.
- the alternating voltage source is preferably set up in such a way that it generates an alternating current with a frequency between 1 kHz and 200 kHz, particularly preferably with 5 kHz.
- the electromigration test device additionally has a heating furnace or heating plate, which is set up in such a way that it heats the conductive structure to be tested.
- An offset temperature can be set in the heater. This is preferably about 200 ° C to 250 ° C.
- FIG. 1 shows an electromigration test device according to an exemplary embodiment of the invention
- FIG. 2 shows a measurement curve of a resistance of a conductive structure over time.
- the electromigration test device has a wafer 108 with a conductive structure 100 to be tested.
- the conductive structure to be tested is made of aluminum.
- the test device has a direct current source 101.
- the DC power source 101 is electrically conductively connected to the conductive structure 100 to be tested.
- the DC power source 101 serves to put the conductive structure 100 under stress. Ie the electrically conductive structure 100 is exposed to conditions by means of an applied direct current of the direct current source, which accelerate the electromigration in the conductive structure 100. This stress condition is an increased electrical current density compared to normal operation of an electronic component.
- the test device has a pulse generator 102. This is connected between the direct current source 101 and the conductive structure 100 to be tested.
- the pulse generator 102 superimposes a symmetrical alternating current on the direct current, which serves as a stress current.
- the symmetrical alternating current is used to heat the electrically conductive structure by means of an ohmic resistance of the electrically conductive structure 100. Since the pulse generator provides a symmetrical alternating current, electromigration is hardly influenced by the electrical current density which is caused by the alternating current. The only effect of the alternating current is to heat the conductive structure 100 to be tested.
- the temperature set in the exemplary embodiment is 262 ° C. In the exemplary embodiment, the temperature is determined by detecting the increase in thermal resistance of the conductive structure. If necessary, the level of the alternating current is readjusted so that a constant temperature and thus constant stress conditions are maintained for the electrically conductive structure.
- the amount of the alternating current required for heating to this temperature is 23.3 mA.
- the frequency of the alternating current is 5 kHz.
- the direct current, which serves as a stress current, is 0.5 mA.
- the test device has a current measuring device 103.
- the current measuring device 103 is integrated in a circuit 104, which couples the conductive structure 100 to be tested, the direct current source 101 and the pulse generator 102 in an electrically conductive manner.
- the effective current which flows through the conductive structure 100 is detected by means of the current measuring device 103.
- the electrical migration test device has a voltage measuring device 105.
- the Voltage measuring device 105 detects the effective electrical voltage, which drops between a first voltage tap 106 and a second voltage tap 107, of which one of the voltage taps is arranged in the start area and the other voltage tap in the end area of the conductive structure, on the electrically conductive structure 100.
- the electromigration test device has a computer (not shown).
- the computer reads in values detected by the voltage measuring device 105 and the current measuring device 104.
- the computer uses the detected and read-in values to determine a resistance of the conductive structure 100 to be tested.
- the temperature of the conductive structure to be tested (stress temperature) is also determined via the resistance determined in this way.
- the computer is also set up so that it adjusts the level of the alternating current so that the stress temperature is constant.
- the conductive structure 100 to be tested is arranged directly on the wafer level of a semiconductor wafer.
- FIG. 2 shows the course over time of the resistance of the electrically conductive structure 100 to be tested, which resistance was determined using the electromigration test device according to the invention.
- the parameters for determining the resistance were an alternating current of 23.3 mA, which corresponds to a temperature of 262 ° C.
- the applied stress current is 0.5 mA.
- the test was carried out over a period of around 10,000 s. A sudden increase 209 in the determined resistance towards the end of the measurement period can be clearly seen.
- electromigration has caused damage to the electrically conductive structure to be tested, as a result of which one or more voids cause a drastic reduction in the conductive material in the line cross section. This causes the resistance to rise suddenly.
- a test to examine electromigration preferably lasts until a significant increase in electrical resistance is registered.
- the invention provides an electromigration test device which enables a quick, simple and inexpensive test of conductive structures to be tested for electromigration.
- the electromigration test device according to the invention does not require an external heating furnace for heating the conductive structure to be tested.
- the embodiment according to the invention does not show the disadvantage of the self-heating test structures according to the prior art, that the two parameters temperature and electrical current density, which influence the electromigration in the conductive structure to be tested, are coupled.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- General Engineering & Computer Science (AREA)
- Testing Or Measuring Of Semiconductors Or The Like (AREA)
- Testing Of Individual Semiconductor Devices (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10228284 | 2002-06-25 | ||
DE10228284 | 2002-06-25 | ||
PCT/DE2003/002112 WO2004001432A1 (de) | 2002-06-25 | 2003-06-25 | Elektromigrations-testvorrichtung und elektromigrations-testverfahren |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1516195A1 true EP1516195A1 (de) | 2005-03-23 |
Family
ID=29795873
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP03740110A Withdrawn EP1516195A1 (de) | 2002-06-25 | 2003-06-25 | Elektromigrations-testvorrichtung und elektromigrations-testverfahren |
Country Status (6)
Country | Link |
---|---|
US (1) | US20060125494A1 (de) |
EP (1) | EP1516195A1 (de) |
JP (1) | JP2005536871A (de) |
CN (1) | CN100412561C (de) |
TW (1) | TWI221908B (de) |
WO (1) | WO2004001432A1 (de) |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7187160B2 (en) * | 2005-07-26 | 2007-03-06 | Higgins James C | Systems and methods for measuring an RMS voltage |
EP1978371A1 (de) | 2007-04-02 | 2008-10-08 | Nxp B.V. | Vorrichtungen und Verfahren zur Überprüfung und Bewertung von Elektromigration |
CN101295002B (zh) * | 2007-04-24 | 2010-09-29 | 中芯国际集成电路制造(上海)有限公司 | 互连线失效检测方法 |
CN101493497B (zh) * | 2008-01-24 | 2011-04-20 | 中芯国际集成电路制造(上海)有限公司 | 一种可提高测试效率的应力迁移测试方法 |
JP2012043924A (ja) * | 2010-08-18 | 2012-03-01 | Sharp Corp | Ledの信頼性評価方法および評価用チップ |
US10732216B2 (en) * | 2012-10-30 | 2020-08-04 | Fifth Electronics Research Institute Of Ministry Of Industry And Information Technology | Method and device of remaining life prediction for electromigration failure |
CN102955121B (zh) * | 2012-10-30 | 2014-11-19 | 工业和信息化部电子第五研究所 | 一种电迁移失效的剩余寿命预测方法和装置 |
US9851397B2 (en) * | 2015-03-02 | 2017-12-26 | Globalfoundries Inc. | Electromigration testing of interconnect analogues having bottom-connected sensory pins |
US9753076B2 (en) | 2016-01-28 | 2017-09-05 | International Business Machines Corporation | Voltage rail monitoring to detect electromigration |
CN106449460B (zh) * | 2016-10-26 | 2019-09-17 | 上海华力微电子有限公司 | 恒温电迁移测试中的电流加速因子评估方法 |
CN107063891B (zh) * | 2017-04-10 | 2023-04-11 | 河南科技大学 | 一种用于热电复合场下电迁移的装置及方法 |
CN107064571B (zh) * | 2017-04-10 | 2023-03-14 | 河南科技大学 | 一种方便装卸测试式样的导电装置及恒温电迁移实验装置 |
DE102020204733A1 (de) * | 2020-04-15 | 2021-10-21 | Robert Bosch Gesellschaft mit beschränkter Haftung | Testvorrichtung, Steuergerätesystem und Verfahren zum Testen |
CN113327864B (zh) * | 2021-04-28 | 2022-06-07 | 长江存储科技有限责任公司 | 一种应力迁移的可靠性评估方法、装置及*** |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4483629A (en) * | 1983-01-05 | 1984-11-20 | Syracuse University | Dynamic testing of electrical conductors |
US5291142A (en) * | 1992-05-08 | 1994-03-01 | Tadahiro Ohmi | Method and apparatus for measuring the resistance of conductive materials due to electromigration |
US5625288A (en) * | 1993-10-22 | 1997-04-29 | Sandia Corporation | On-clip high frequency reliability and failure test structures |
EP0907085A1 (de) * | 1997-10-03 | 1999-04-07 | Interuniversitair Microelektronica Centrum Vzw | Verfahren zum Messen von Wiederstandsänderungen durch Elektromigration |
US6223686B1 (en) * | 1998-02-06 | 2001-05-01 | Shimadzu Corporation | Apparatus for forming a thin film by plasma chemical vapor deposition |
JP2002026099A (ja) * | 2000-07-12 | 2002-01-25 | Nec Kyushu Ltd | エレクトロマイグレーション評価回路 |
-
2003
- 2003-06-19 TW TW092116720A patent/TWI221908B/zh not_active IP Right Cessation
- 2003-06-25 CN CNB038148048A patent/CN100412561C/zh not_active Expired - Fee Related
- 2003-06-25 US US10/519,659 patent/US20060125494A1/en not_active Abandoned
- 2003-06-25 EP EP03740110A patent/EP1516195A1/de not_active Withdrawn
- 2003-06-25 JP JP2004514570A patent/JP2005536871A/ja active Pending
- 2003-06-25 WO PCT/DE2003/002112 patent/WO2004001432A1/de not_active Application Discontinuation
Non-Patent Citations (2)
Title |
---|
None * |
See also references of WO2004001432A1 * |
Also Published As
Publication number | Publication date |
---|---|
TWI221908B (en) | 2004-10-11 |
TW200403441A (en) | 2004-03-01 |
CN1662823A (zh) | 2005-08-31 |
US20060125494A1 (en) | 2006-06-15 |
CN100412561C (zh) | 2008-08-20 |
JP2005536871A (ja) | 2005-12-02 |
WO2004001432A1 (de) | 2003-12-31 |
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