Impact of Microstructure of Alternative Al-Si-V-Pd Alloy Films on Interconnect Reliability, Compared to Al-Si-Cu

1994 ◽  
Vol 337 ◽  
Author(s):  
A.G. Dirks ◽  
R.A. Augur ◽  
S. Kordić ◽  
R.A.M. Wolters
Keyword(s):  
Grain Boundaries ◽  
Integrated Circuit ◽  
Void Formation ◽  
Quaternary Alloy ◽  
Alloy Films ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Pd Alloy ◽  
Interconnect Reliability ◽  
Key Issues

ABSTRACTDifficulty during plasma etching and post-etch corrosion are major drawbacks of Al-Si-Cu alloy films, when used for integrated circuit interconnect. Moreover, the relatively large solute mobility of Cu in Al may lead to void formation by precipitate coarsening. As integrated circuit dimensions decrease reliability issues, such as electromigration and mechanical stress voiding, are becoming increasingly important. At present several types of Al alloys are considered as possible alternatives for Al-Si-Cu: Al-Pd, Al-Sc, Al-Pd-Cu, Al-Si-Pd, Al-Si-V, Al-Si-Sc, Al-Si-Pd-Nb, and Al-Si-V-Pd. The latter quaternary alloy has been designed such as to combine the positive aspects of both Pd and V. In comparison with Cu in Al, a) the (low temperature) solid solubility is negligible for Pd and small for V, and b) the mobility is similar for Pd, but very small for V.With transmission-electron microscopy, passivated Al-Si-Cu alloy films have been studied after thermal stressing at 200 °C: ө-Al2Cu coarsening was observed together with void condensation. Lifetests on unpassivated Al-Si-V-Pd alloys at 180 °C and 2xl06A/cm2 have shown an extremely high resistance to electromigration. Electromigration and microstructural data on these quaternary alloys will be presented. These findings suggest how the microstructure is stabilized by the combined action of the V and Pd solute atoms, a) by nm-scale (A1,V) precipitates within the Al grains and b) by small (Al,Pd) particles at the Al grain boundaries. Furthermore, the key issues in terms of reliability related microstructural phenomena are both solute and solvent mobilities in grain interiors as well as along interfaces and grain boundaries. Arguments will be given showing that at low solute concentrations the metals (V and Pd) each by themselves are not effective enough to influence the solvent motion of aluminium along interfaces and grain boundaries significantly. The combination of the two metals, however, was found to be very effective.

The Microstructural Nature of Electromigration and Mechanical Stress Voids in Integratedcircuit Interconnect

1993 ◽  
Vol 309 ◽  
Author(s):  
Jamie H. Rose ◽  
Terry Spooner
Keyword(s):  
Grain Boundary ◽  
Integrated Circuit ◽  
Boundary Diffusion ◽  
Void Formation ◽  
Parallel Line ◽  
Relative Displacement ◽  
Test Conditions ◽  
Line Array ◽  
Interconnect Reliability ◽  
Diffusion Paths

AbstractIt is well known that stress and electromigration induced voiding is of major concern for integrated circuit interconnect reliability. However, there has been little systematiccharacterization of void morphology and crystallography in ever more technologically important narrow, “near-bamboo” conducting lines. Prior reports indicate thatvoids are typically wedge or slit shaped, with failure often associated with slit voids.Void face habit plane is most often reported to be {111}. Wedge and slit void morphology and crystallography have been studied in comb/serpentine and parallel line array test structures. In virtually all cases, void faces are {111} oriented. In contrast to earlier studies, intragranular wedge stress voids have been observed. All electromigration opens were due to slit voids; these were typically intragranular, in contradiction to current theories of void formation, and likely are mechanical fractures. Under accelerated test conditions, non-grain boundary diffusion paths appear to operate at distances of tens of micrometers. Relative displacement between wedge voids and attached grain boundaries occurs where a wedge face lies on a near common {111} plane for the two grains. It is suggested that slit voids are intragranular under both stress and electromigration conditions and likely associated with local interconnect depassivation. Based solely on appearance and crystallography, no void can uniquely be identified as due to stress alone or electromigration alone.

Investigation of Grain Boundaries in an Al-Mg-Si-Cu Alloy

2014 ◽  
Vol 794-796 ◽  
pp. 951-956 ◽  
Author(s):  
Jon Holmestad ◽  
Martin Ervik ◽  
Calin D. Marioara ◽  
John Charles Walmsley
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Transmission Electron Microscopy ◽  
Grain Boundaries ◽  
Solution Heat Treatment ◽  
High Angle ◽  
Corrosion Properties ◽  
X Ray ◽  
Cu Alloy ◽  
Transmission Electron

The grain boundaries of a fibrous Al-Mg-Si-Cu alloy have been investigated with Transmission Electron Microscopy. The compositions have been mapped by Energy Dispersive X-ray Spectroscopy. The alloy has been aged for 12 hours at 155°C after solution heat treatment and is in a slightly underaged condition. The precipitates nucleated on the high angle grain boundaries are coarse, while the precipitates on the low angle grain boundaries are smaller and more numerous. The precipitates on both types of grain boundaries has been identified as Q'-type. Copper is segregated to both the low and high angle grain boundaries. The effect of this segregation will be discussed with regards to the corrosion properties of the alloy.

Deviations from Ideal Decagonal Symmetry in Electron Diffraction Patterns of the “Decagonal” Phase in the Al-Co-Cu Alloy System

1991 ◽  
Vol 49 ◽  
pp. 914-915
Author(s):  
Atul S. Ramani ◽  
Earle R. Ryba ◽  
Paul R. Howell
Keyword(s):  
Electron Microscope ◽  
Alloy System ◽  
Nominal Composition ◽  
Dimensional Lattice ◽  
3 Dimensional ◽  
Decagonal Phase ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Lattice Periodicity ◽  
Diffraction Patterns

The “decagonal” phase in the Al-Co-Cu system of nominal composition Al65CO15Cu20 first discovered by He et al. is especially suitable as a topic of investigation since it has been claimed that it is thermodynamically stable and is reported to be periodic in the dimension perpendicular to the plane of quasiperiodic 10-fold symmetry. It can thus be expected that it is an important link between fully periodic and fully quasiperiodic phases. In the present paper, we report important findings of our transmission electron microscope (TEM) study that concern deviations from ideal decagonal symmetry of selected area diffraction patterns (SADPs) obtained from several “decagonal” phase crystals and also observation of a lattice of main reflections on the 10-fold and 2-fold SADPs that implies complete 3-dimensional lattice periodicity and the fundamentally incommensurate nature of the “decagonal” phase. We also present diffraction evidence for a new transition phase that can be classified as being one-dimensionally quasiperiodic if the lattice of main reflections is ignored.

Characterization of RF Sputtered ZnO Piezoelectric Films Using Transmission Electron Microscope

1975 ◽  
Vol 33 ◽  
pp. 86-87
Author(s):  
Kemining W. Yeh ◽  
Richard S. Muller ◽  
Wei-Kuo Wu ◽  
Jack Washburn
Keyword(s):  
Integrated Circuit ◽  
Acoustic Waves ◽  
New Technology ◽  
Surface Acoustic Waves ◽  
Electromechanical Properties ◽  
Leading Role ◽  
Saw Devices ◽  
Transmission Electron ◽  
High Degree

Considerable and continuing interest has been shown in the thin film transducer fabrication for surface acoustic waves (SAW) in the past few years. Due to the high degree of miniaturization, compatibility with silicon integrated circuit technology, simplicity and ease of design, this new technology has played an important role in the design of new devices for communications and signal processing. Among the commonly used piezoelectric thin films, ZnO generally yields superior electromechanical properties and is expected to play a leading role in the development of SAW devices.

Ion thinning of integrated circuit transverse specimens for transmission electron microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1426-1427
Author(s):  
F. Shaapur
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Integrated Circuit ◽  
Substrate Surface ◽  
Homogeneous Material ◽  
Material System ◽  
Ion Milling ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Motion Profile

Non-uniform ion-thinning of heterogenous material structures has constituted a fundamental difficulty in preparation of specimens for transmission electron microscopy (TEM). A variety of corrective procedures have been developed and reported for reducing or eliminating the effect. Some of these techniques are applicable to any non-homogeneous material system and others only to unidirectionalfy heterogeneous samples. Recently, a procedure of the latter type has been developed which is mainly based on a new motion profile for the specimen rotation during ion-milling. This motion profile consists of reversing partial revolutions (RPR) within a fixed sector which is centered around a direction perpendicular to the specimen heterogeneity axis. The ion-milling results obtained through this technique, as studied on a number of thin film cross-sectional TEM (XTEM) specimens, have proved to be superior to those produced via other procedures.XTEM specimens from integrated circuit (IC) devices essentially form a complex unidirectional nonhomogeneous structure. The presence of a variety of mostly lateral features at different levels along the substrate surface (consisting of conductors, semiconductors, and insulators) generally cause non-uniform results if ion-thinned conventionally.

The formation of low temperature Cu3Si in Ag(Cu)/Si structure upon annealing and its effects on adhesion and resistivity

2003 ◽  
Vol 766 ◽  
Author(s):  
Sungjin Hong ◽  
Seob Lee ◽  
Yeonkyu Ko ◽  
Jaegab Lee
Keyword(s):  
Low Temperature ◽  
Auger Electron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Si Substrate ◽  
Copper Silicide ◽  
Alloy Films ◽  
Cu Alloy ◽  
Cu Film ◽  
Rapid Drop

AbstractThe annealing of Ag(40 at.% Cu) alloy films deposited on a Si substrate at 200 – 800 oC in vacuum has been conducted to investigate the formation of Cu3Si at the Ag-Si interface and its effects on adhesion and resistivity of Ag(Cu)/Si structure. Auger electron spectroscopy(AES) analysis showed that annealing at 200°C allowed a diffusion of Cu to the Si surface, leading to the significant reduction in Cu concentration in Ag(Cu) film and thus causing a rapid drop in resistivity. In addition, the segregated Cu to the Si surface reacts with Si, forming a continuous copper silicide at the Ag(Cu)/Si interface, which can contribute to an enhanced adhesion of Ag(Cu)/Si annealed at 200 oC. However, as the temperature increases above 300°C, the adhesion tends to decrease, which may be attributed to the agglomeration of copper silicide beginning at around 300°C.

Atomic and Electronic Structure of Boron-Doped Diamond Grain Boundaries Studied by Arhvtem and ab-Initio Calculation

2003 ◽  
Vol 764 ◽  
Author(s):  
Hiroyuki Togawa ◽  
Hideki Ichinose
Keyword(s):  
Ab Initio ◽  
Grain Boundaries ◽  
Ab Initio Calculation ◽  
Structure Model ◽  
Boron Doped Diamond ◽  
Boron Doped ◽  
Transmission Electron ◽  
Diamond Grain ◽  
Electron Energy Loss ◽  
Atomic And Electronic Structure

AbstractAtomic resolution high-voltage transmission electron microscopy and electron energy loss spectroscopy were performed on grain boundaries of boron-doped diamond, cooperated with the ab-initio calculation. Segregated boron in the {112}∑3 boundary was caught by the EELS spectra. The change in atomic structure of the segregated boundary was successfully observed from the image by ARHVTEM. Based on the ARHVTEM image, a segregted structure model was proposed.

TEM Sample Preparation Tricks for Advanced DRAMs

2015 ◽  
Author(s):  
Ching Shan Sung ◽  
Hsiu Ting Lee ◽  
Jian Shing Luo
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Sample Preparation ◽  
Integrated Circuit ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Tem Analysis ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Characterization Of Materials

Abstract Transmission electron microscopy (TEM) plays an important role in the structural analysis and characterization of materials for process evaluation and failure analysis in the integrated circuit (IC) industry as device shrinkage continues. It is well known that a high quality TEM sample is one of the keys which enables to facilitate successful TEM analysis. This paper demonstrates a few examples to show the tricks on positioning, protection deposition, sample dicing, and focused ion beam milling of the TEM sample preparation for advanced DRAMs. The micro-structures of the devices and samples architectures were observed by using cross sectional transmission electron microscopy, scanning electron microscopy, and optical microscopy. Following these tricks can help readers to prepare TEM samples with higher quality and efficiency.

A Methodology to Reduce Ion Beam Induced Damage in TEM Specimens Prepared by FIB

2002 ◽  
Author(s):  
Chin Kai Liu ◽  
Chi Jen. Chen ◽  
Jeh Yan.Chiou ◽  
David Su
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Sample Preparation ◽  
Integrated Circuit ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Specimen Preparation ◽  
Tem Analysis ◽  
Sensitive Issue ◽  
Transmission Electron

Abstract Focused ion beam (FIB) has become a useful tool in the Integrated Circuit (IC) industry, It is playing an important role in Failure Analysis (FA), circuit repair and Transmission Electron Microscopy (TEM) specimen preparation. In particular, preparation of TEM samples using FIB has become popular within the last ten years [1]; the progress in this field is well documented. Given the usefulness of FIB, “Artifact” however is a very sensitive issue in TEM inspections. The ability to identify those artifacts in TEM analysis is an important as to understanding the significance of pictures In this paper, we will describe how to measure the damages introduced by FIB sample preparation and introduce a better way to prevent such kind of artifacts.

Sample Preparation and Preservation for TEM Analysis of Copper Interconnect Integrated Circuit

2004 ◽  
Author(s):  
Qiang Gao ◽  
Mark Zhang ◽  
Ming Li ◽  
Chorng Niou ◽  
W.T. Kary Chien
Keyword(s):  
Integrated Circuit ◽  
Thermal Exposure ◽  
Ambient Atmosphere ◽  
Ion Milling ◽  
Tem Analysis ◽  
Single Beam ◽  
Copper Interconnect ◽  
Beam Modulation ◽  
Area Of Interest ◽  
Transmission Electron

Abstract This paper examines copper-interconnect integrated circuit transmission electron microscope (TEM) sample contamination. It investigates the deterioration of the sample during ion milling and storage and introduces prevention techniques. The paper discusses copper grain agglomeration issues barrier/seed step coverage checking. The high temperature needed for epoxy solidifying was found to be harmful to sidewall coverage checking of seed. Single beam modulation using a glass dummy can efficiently prevent contamination of the area of interest in a TEM sample during ion milling. Adoption of special low-temperature cure epoxy resin can greatly reduce thermal exposure of the sample and prevent severe agglomeration of copper seed on via sidewall. TEM samples containing copper will deteriorate when stored in ordinary driers and sulphur contamination was found at the deteriorated point on the sample. Isolation of the sample from the ambient atmosphere has been verified to be very effective in protecting the TEM sample from deterioration.

Sign in / Sign up

Export Citation Format

Share Document