Effect of Cu Migration in a Field Induced Dielectric Failure

AbstractFor the study of dielectric failures by Cu migration, TDDB (time dependent dielectric breakdown) and 1-D FDM simulation was carried out. We tested TDDB using a simple MIS structure with no barrier Cu electrode. From our TDDB results, the TTF's in the acceleration condition and the characteristic parameter of TDDB were obtained. In the simulation parts, 1-D FDM simulation was accomplished considering space charge effect due to Cu ions.The objective of TDDB is to predict of TTF (time to failure) in the service condition form the results of an accelerating condition. The characteristic of TTF's follows E model in the accelerating condition, in the service condition, the deviation from E model was observed. This different characteristic of TTF can be explained by the mechanism of Cu migration enhanced by an applied E field. Our simulation and TDDB results reveal that the deviation from E model does not mean the change of failure mechanism, but it shows the characteristics of Cu migration.

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950 Volt 4H-SiC MOSFETs: DC and Transient Performance and Gate Oxide Reliability

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.1131 ◽

2008 ◽

Vol 600-603 ◽

pp. 1131-1134 ◽

Cited By ~ 2

Author(s):

Kevin Matocha ◽

Zachary Stum ◽

Steve Arthur ◽

Greg Dunne ◽

Ljubisa Stevanovic

Keyword(s):

Electric Field ◽

Applied Electric Field ◽

Dielectric Breakdown ◽

Gate Oxide ◽

Time Dependent ◽

Time To Failure ◽

Time Dependent Dielectric Breakdown ◽

Oxide Reliability ◽

Blocking Voltage ◽

Mean Time

SiC vertical MOSFETs were fabricated and characterized to achieve a blocking voltage of 950 Volts and a specific on-resistance of 8.4 mW-cm2. Extrapolations of time-dependent dielectric breakdown measurements versus applied electric field indicate that the gate oxide mean-time to failure is approximately 105 hours at 250°C.

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Time-Dependent Dielectric Breakdown of Thermal Oxides on 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.675 ◽

2007 ◽

Vol 556-557 ◽

pp. 675-678 ◽

Cited By ~ 9

Author(s):

Kevin Matocha ◽

Richard Beaupre

Keyword(s):

Electric Fields ◽

Dielectric Breakdown ◽

Time Dependent ◽

Time To Failure ◽

Mean Time To Failure ◽

Failure Times ◽

Time Dependent Dielectric Breakdown ◽

Mean Time ◽

Nordheim Tunneling ◽

Thermally Grown

Thermal oxides on 4H-SiC are characterized using time-dependent dielectric breakdown techniques at electric fields between 6 and 10 MV/cm. At 250°C, oxides thermally-grown using N2O with NO annealing achieve a mean time to failure (MTTF) of 2300 hours at 6 MV/cm. Oxides grown in steam with NO annealing show approximately four times longer MTTF than N2O-grown oxides. At electric fields greater than 8 MV/cm, Fowler-Nordheim tunneling significantly reduces the expected failure times. For this reason, extrapolation of mean-time to failure at low fields must be performed by datapoints measured at lower electric fields.

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Time Dependent Dielectric Breakdown and Time to Failure Analysis of 4H-SiC Power MOSFET

10.7567/ssdm.2010.p-14-15l ◽

2010 ◽

Author(s):

S. Bose

Keyword(s):

Failure Analysis ◽

Dielectric Breakdown ◽

Time Dependent ◽

Time To Failure ◽

Power Mosfet ◽

Time Dependent Dielectric Breakdown

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Assessment of Reliability of cap layers used in Cu-Black DiamondTM Interconnects

MRS Proceedings ◽

10.1557/proc-766-e2.9 ◽

2003 ◽

Vol 766 ◽

Author(s):

Ahila Krishnamoorthy ◽

N.Y. Huang ◽

Shu-Yunn Chong

Keyword(s):

Dielectric Layer ◽

Dielectric Breakdown ◽

Copper Ions ◽

Dielectric Strength ◽

Time Dependent ◽

Breakdown Field ◽

Field Range ◽

Time Dependent Dielectric Breakdown ◽

Voltage Ramp ◽

Low K

AbstractBlack DiamondTM. (BD) is one of the primary candidates for use in copper-low k integration. Although BD is SiO2 based, it is vastly different from oxide in terms of dielectric strength and reliability. One of the main reliability concerns is the drift of copper ions under electric field to the surrounding dielectric layer and this is evaluated by voltage ramp (V-ramp) and time dependent dielectric breakdown (TDDB). Metal 1 and Metal 2 intralevel comb structures with different metal widths and spaces were chosen for dielectric breakdown studies. Breakdown field of individual test structures were obtained from V-ramp tests in the temperature range of 30 to 150°C. TDDB was performed in the field range 0.5 – 2 MV/cm. From the leakage between combs at the same level (either metal 1 or metal 2) Cu drift through SiC/BD or SiN/BD interface was characterized. It was found that Cu/barrier and barrier/low k interfaces functioned as easy paths for copper drift thereby shorting the lines. Cu/SiC was found to provide a better interface than Cu/SiN.

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