Observation of grain superstructure in thin aluminum films by orientation imaging microscopy

The correlation of aluminum alloy reliability data to microstructure has long been the goal of those scientists seeking to model electromigration behavior of interconnects. Traditionally, microstructural information has been acquired through x-ray diffraction , and transmission electron microscopy (TEM). However, each of these techniques is capable of delivering only part of the characterization whole. We describe the application of orientation imaging microscopy (OIM) to thin aluminum alloy films and demonstrate its versatility in providing the key microstructural reliability parameters: namely texture and grain size, as well as providing insight to the microstructure of grain boundaries.OIM was performed on an electromigration test structure (figure 1). The Al-alloy was deposited on titanium and capped with an anti-reflective titanium nitride. Subsequently, the test structure was patterned and capped with a multilayer blanket consisting of silicon nitride (SiN), and SiO2. The structure was annealed after the SOG deposition at 450° C for 90 minutes, seeing no electrical stressing. The die was removed from the package and deprocessed before the OIM was acquired.

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Texture and Microstructure Effects on Electromigration Behavior of Aluminum Metallization

MRS Proceedings ◽

10.1557/proc-225-21 ◽

1991 ◽

Vol 225 ◽

Cited By ~ 10

Author(s):

D. B. Knorr ◽

K. P. Rodbell ◽

D. P. Tracy

Keyword(s):

Grain Size ◽

Standard Deviation ◽

Pure Aluminum ◽

Time To Failure ◽

X Ray Diffraction ◽

Aluminum Films ◽

Failure Data ◽

Transmission Electron ◽

Aluminum Metallization ◽

Microstructure Effects

ABSTRACTPure aluminum films are deposited under a variety of conditions to vary the crystallographic texture. After patterning and annealing at 400°C for 1 hour, electromigration tests are performed at several temperatures. Failure data are compared on the basis of t50 and standard deviation. Microstructure is quantified by transmission electron microscopy for grain size and grain size distribution and by X-ray diffraction for texture. A strong (111) texture significantly improves the electromigration lifetime and decreases the standard deviation in time to failure. This improvement correlates with both the fraction and sharpness of the (111) texture component.

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Emittance of Boehmite and Alumina Films on 6061 Aluminum Alloy Between 295 and 773 K

Journal of Heat Transfer ◽

10.1115/1.2910523 ◽

1991 ◽

Vol 113 (1) ◽

pp. 185-189 ◽

Cited By ~ 1

Author(s):

T. G. Kollie ◽

T. D. Radcliff ◽

F. J. Weaver

Keyword(s):

Aluminum Alloy ◽

National Laboratory ◽

X Ray Diffraction ◽

Anodized Aluminum ◽

Aluminum Films ◽

Oak Ridge ◽

Alumina Films ◽

Loss Of Coolant Accident ◽

Total Hemispherical Emittance ◽

Loss Of Coolant

The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminum alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al2O3·H2O), which dehydrated to alumina (Al2O3) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.

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The Effect of Tungsten on the Nucleation and Growth of thin Aluminum Alloy Films

MRS Proceedings ◽

10.1557/proc-317-227 ◽

1993 ◽

Vol 317 ◽

Author(s):

Bea CAO ◽

N. David Theodore ◽

Hank Shin ◽

Peter Fejes ◽

Les Hendrickson

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Nucleation And Growth ◽

Growth Behavior ◽

Aluminum Films ◽

Surface Energies ◽

Transmission Electron ◽

Thin Aluminum ◽

Scanning Electron

ABSTRACTA variety of alloying elements are currently being investigated for their effects on the mechanical properties and reliability of thin aluminum films. In the present study, scanning electron microscopy and transmission electron microscopy are used to study the nucleation and growth of Al-1.5wt%Cu and Al-1.5wt% Cu-0.2wt% W films. Differences in Microstructure, nucleation and growth behavior are observed and are explained in terms of changes in surface energies and atomic Mobilities.

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The Effect of Collimation On Sputtered Alcusi and Almg Microstructures And Electromigration Failure Characteristics

MRS Proceedings ◽

10.1557/proc-309-87 ◽

1993 ◽

Vol 309 ◽

Cited By ~ 5

Author(s):

Thomas J. Licata ◽

Timothy D. Sullivan ◽

Roy S. Bass ◽

James G. Ryan ◽

David B. Knorr

Keyword(s):

Electron Microscope ◽

Sputter Deposition ◽

Al Alloy ◽

X Ray Diffraction ◽

Failure Characteristics ◽

X Ray ◽

Aspect Ratios ◽

Transmission Electron ◽

Lower Strain ◽

Induced Changes

AbstractIncreasing circuit densities produce higher metal wiring aspect ratios, and more difficult feature fill for damascene processing. One method of extending the use of sputter deposition to challenging aspect ratios is to collimate the sputtered flux using a collimator plate, and to avoid randomizing the collimated flux by using low process pressures corresponding to long sputtered atom mean free paths. In this paper, we discuss our fabrication of damascene AI-0.5Cu-2Si and AI-2Mg wiring using both collimated and uncollimated sputtering, and our observations of collimation-induced changes in Al alloy electromigration and microstructure. Our experiments show that collimation has only a small effect on AlCuSi, but a large effect on AIMg. Specifically, the median time to electromigration failure for collimated AIMg was ∼10X the value for uncollimated AlMg and ∼6X the values for collimated and uncollimated AlCuSi. Transmission electron microscope and x-ray diffraction analyses of these films show that the collimation-induced improvement in AIMg t50 is associated with the formation of smaller, lower strain grains which are clustered in very well-oriented (111) domains. We propose that the advantageous AlMg microstructure results from enhanced texture produced by aspects of the collimated deposition active in the absence of incoherent precipitates.

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Microstructural Evolution and Mechanical Properties of Ultrafine Grained Commercially Pure 1100 Aluminum Alloy Processed by Accumulative Roll-Bonding (ARB)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.625 ◽

2004 ◽

Vol 449-452 ◽

pp. 625-628 ◽

Cited By ~ 17

Author(s):

Yong Suk Kim ◽

T.O. Lee ◽

Dong Hyuk Shin

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Microstructural Evolution ◽

Sliding Wear ◽

Al Alloy ◽

Commercially Pure ◽

Transmission Electron ◽

Ultrafine Grained ◽

Average Grain Size ◽

Accumulated Strain

The ARB process has been carried out up to seven cycles on a commercial purity 1100 aluminum alloy to obtain ultra-fine grains with the average grain size of 500 nm. Microstructural evolution of the ARB processed aluminum alloy was examined by a transmission electron microscopy as a function of accumulated total strain. Mechanical properties including hardness, tensile property, and sliding wear characteristics of the severely deformed Al alloy were also investigated. Grain boundaries of the ARB processed alloy were diffusive and poorly defined after the initial ARB cycles, however they changed to well-defined high angle boundaries with the increase of the accumulated strain. Though hardness and strength of the ARB processed alloy were enhanced significantly, wear resistance of the processed alloy hardly increased. The mechanical properties were discussed in connection with the microstructure.

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Randomly oriented twin domains in electrodeposited silver dendrites

Journal of the Serbian Chemical Society ◽

10.2298/jsc140306045i ◽

2015 ◽

Vol 80 (1) ◽

pp. 107-113 ◽

Cited By ~ 4

Author(s):

Evica Ivanovic ◽

Nebojsa Nikolic ◽

Velimir Radmilovic

Keyword(s):

Electron Microscopy ◽

Orientation Imaging Microscopy ◽

Dark Field ◽

High Angle ◽

Orientation Imaging ◽

Transmission Electron ◽

Annular Dark Field ◽

Silver Dendrites ◽

Z Contrast ◽

Scanning Electron

Silver dendrites were prepared by electrochemical deposition. The structures of Ag dendrites, the type of twins and their distribution were investigated by scanning electron microscopy (SEM), Z-contrast high angle annular dark field transmission electron microscopy (HAADF), and crystallografically sensitive orientation imaging microscopy (OIM). The results revealed that silver dendrites are characterized by the presence of randomly distributed 180? rotational twin domains. The broad surface of dendrites was of the {111} type. Growth directions of the main dendrite stem and all branches were of <112> type.

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A transmission electron microscopy study of hillocks in thin aluminum films

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.585790 ◽

1991 ◽

Vol 9 (1) ◽

pp. 58 ◽

Cited By ~ 64

Author(s):

Fredric Ericson

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Transmission Electron Microscopy Study ◽

Aluminum Films ◽

Transmission Electron ◽

Thin Aluminum

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Quantitative SiGe TEM Elemental Analysis in FinFET Test Structures

ISTFA 2015: Conference Proceedings from the 41st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2015p0120 ◽

2015 ◽

Author(s):

James Demarest ◽

John Bruley

Keyword(s):

Silicon Germanium ◽

Semiconductor Device ◽

Three Dimensional ◽

Test Structure ◽

X Ray Diffraction ◽

X Ray ◽

Device Scaling ◽

Transmission Electron ◽

Calibration Samples ◽

Performance Gains

Abstract As semiconductor device scaling continues to reduce the structure size, device geometries are also changing to three dimensional structures such as finFETs, and the materials which compose the devices are also evolving to obtain additional device performance gains. The material change studied in this paper is the introduction of silicon germanium into the electrically active region of a finFET test structure. The paper demonstrates a quantitative energy dispersive X-ray spectroscopy transmission electron microscopy (TEM) technique through the use of blanket film calibration samples of known concentration characterized by X-ray diffraction. The technique is used to identify a test structure issue which could only be diagnosed with a technique having nanometer spatial resolution and atomic percent sensitivity. The results of the test structure analysis are independently verified by the complementary TEM electron energy loss spectroscopy technique.

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Characterization of Cu-Al alloy/SiO2 interface microstructure

MRS Proceedings ◽

10.1557/proc-615-g7.5.1 ◽

2000 ◽

Vol 615 ◽

Cited By ~ 1

Author(s):

Pei-I Wang ◽

S. P. Murarka ◽

G.-R. Yang ◽

E. Barnat ◽

T.-M. Lu ◽

...

Keyword(s):

Interfacial Layer ◽

Alloy Film ◽

Al Alloy ◽

X Ray Diffraction ◽

Adhesion Promoter ◽

Adhesion Promoters ◽

Barrier Formation ◽

Transmission Electron ◽

Before And After ◽

Sputter Deposited

ABSTRACTCu-Al alloys have been recommended for application as the diffusion barriers/adhesion promoters for advanced copper based metallization schemes. This approach to barrier formation is to generate an ultra-thin interfacial layer through Cu alloying without significantly affecting the resistivity of Cu. In this paper the microstructure of the bilayers of Cu/Cu-5 at%Al and Cu-5 at%Al/Cu sputter deposited on SiO2 before and after thermal annealing is investigated by transmission electron microscopy (TEM). Interfacial layer is observed in both cases. The variation of the resistance of the Cu-Al alloy film is consistent with its microstructure. The x-ray diffraction (XRD) spectra of Cu-5 at%Al on SiO2 shows that the addition of Al into Cu intends to favor the Cu (111) texture. These results will be presented and discussed showing that films of Cu doped with Al appear to act as a suitable barrier and adhesion promoter between SiO2 and Cu.

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