The Effects of the Mechanical Properties of the Confinement Material on Electromigration in Metallic Interconnects

2000 ◽  
Vol 15 (8) ◽  
pp. 1797-1802 ◽  
Author(s):  
Stefan P. Hau-Riege ◽  
Carl V. Thompson

New low-dielectric-constant interlevel dielectrics are being investigated as alternatives to SiO2 for future integrated circuits. In general, these materials have very different mechanical properties from SiO2. In the standard model, electromigration-induced stress evolution caused by changes in the number of available lattice sites in interconnects is described by an effective elastic modulus, B. Finite element calculations were carried out to obtain B as a function of differences in the modulus, E, of interlevel dielectrics, for several stress-free homogeneous dilational strain configurations, for several line aspect ratios, and for different metallization schemes. In contradiction to earlier models, we found that for Cu-based metallization schemes with liners, a decrease in E by nearly two orders of magnitude has a relatively small effect on B, changing it by less than a factor of 2. However, B, and therefore the reliability of Cu interconnects, can be strongly dependent on the modulus and thickness of the liner material.

2000 ◽  
Vol 612 ◽  
Author(s):  
Stefan P. Hau-Riege ◽  
Carl V. Thompson

AbstractNew low-dielectric-constant inter-level dielectrics are being investigated as alternatives to SiO2 for future integrated circuits. In general, these materials have very different mechanical properties from SiO2. In the standard model, electromigration-induced stress evolution caused by changes in the number of available lattice sites in interconnects is described by an effective elastic modulus, B. Finite element calculations have been carried out to obtain B as a function of differences in the modulus, E, of interlevel dielectrics, for several stress-free homogeneous dilational strain configurations, for several line aspect ratios, and for different metallization schemes. In contradiction to earlier models, we find that for Cu-based metallization schemes with liners, a decrease in E by nearly two orders of magnitude has a relatively small effect on B, changing it by less than a factor of 2. However, B, and therefore the reliability of Cu interconnects can be strongly dependent on the modulus and thickness of the liner material.


2003 ◽  
Vol 766 ◽  
Author(s):  
Jin-Heong Yim ◽  
Jung-Bae Kim ◽  
Hyun-Dam Jeong ◽  
Yi-Yeoul Lyu ◽  
Sang Kook Mah ◽  
...  

AbstractPorous low dielectric films containing nano pores (∼20Å) with low dielectric constant (<2.2), have been prepared by using various kinds of cyclodextrin derivatives as porogenic materials. The pore structure such as pore size and interconnectivity can be controlled by changing functional groups of the cyclodextrin derivatives. We found that mechanical properties of porous low-k thin film prepared with mCSSQ (modified cyclic silsesquioxane) precursor and cyclodextrin derivatives were correlated with the pore interconnection length. The longer the interconnection length of nanopores in the thin film, the worse the mechanical properties of the thin film (such as hardness and modulus) even though the pore diameter of the films were microporous (∼2nm).


1994 ◽  
Vol 338 ◽  
Author(s):  
J. J. Clement ◽  
C. V. Thompson ◽  
A. Enver

ABSTRACTAtomic transport due to electromigration in interconnect lines in integrated circuits depends strongly on temperature. Therefore temperature nonuniformities can create sites of atomic flux divergence resulting in material accumulation or depletion leading to failure. The mechanical stress which will evolve at the sites of material flux divergence will oppose the electromigration driving force. A model is developed to describe the stress evolution during electromigration in the presence of temperature nonuniformnities. Solutions of the differential equations describing the electromigration-induced stress buildup are calculated numerically. The solutions are compared to experimental data in the literature.


RSC Advances ◽  
2015 ◽  
Vol 5 (82) ◽  
pp. 66511-66517 ◽  
Author(s):  
Albert S. Lee ◽  
Sung Yeoun Oh ◽  
Seung-Sock Choi ◽  
He Seung Lee ◽  
Seung Sang Hwang ◽  
...  

Low dielectric constant poly(methyl)silsesquioxane spin-on-glass resins incorporating a cyclic precursor exhibited exceptional mechanical properties to withstand CMP processes.


2007 ◽  
Vol 990 ◽  
Author(s):  
Olivier Gourhant ◽  
Vincent Jousseaume ◽  
Laurent Favennec ◽  
Aziz Zenasni ◽  
Patrick Maury ◽  
...  

ABSTRACTThe increase of integrated circuits performances requires ultra-low dielectric constant (ULK) materials to minimize the drawbacks of miniaturization. Amorphous SiOCH are promising candidates for ULK materials as porosity can be introduced via a two steps elaboration. In a first step, organo-silicon species and organic species are co-deposited by PECVD. Then, a thermal annealing, alone or assisted by UV radiation, removes the organic labile phase and creates pore inclusions into the final material. In this work, the extendibility of this porogen approach is investigated in order to lower the dielectric constant. An increase of the porogen loading in hybrid film is studied by tuning the precursors ratio injected in the plasma gas feed. The increase of organic species amount is operated in order to create more pores sites. However, the post-treatment does not lead automatically to higher porosity. Actually, an increase of the porosity is observed only until a porogen loading limit and decreases above this limit. The shrinkage of the film during the post-treatment can explain this limitation. For high ratios of porogen, the film shrinkage increases drastically and leads to a decrease of the porosity finally created. At last, the link between porosity and dielectric constant is enlightened and a minimum in term of K value is reached with both post-treatments: dielectric constant of 2.1 and 2.3 are obtained using respectively thermal treatment and UV curing.


Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1383
Author(s):  
Panpan Zhang ◽  
Lize Zhang ◽  
Ke Zhang ◽  
Jiupeng Zhao ◽  
Yao Li

Due to the high value of its dielectric constant, polyimide does not meet the requirements of the development of integrated circuits and high-frequency printed circuits. The development of novel low dielectric constant polyimide materials for the preparation of flexible copper clad laminates is of theoretical and practical significance in the application of polyimide for 5G communications. In this work, different fluorinated graphene/polyamic acids (FG/PAA) were used as the precursor, and the porous polyimide film was successfully prepared by phase inversion. The dielectric constant of the porous polyimide film is relatively low, being less than 1.7. When the content of fluorinated graphene is 0.5 wt%, the overall dielectric performance of the porous film is the best, with a dielectric constant of 1.56 (10 kHz) and a characteristic breakdown field strength of 56.39 kV/mm. In addition, the mechanical properties of the film are relatively poor, with tensile strengths of 13.87 MPa (0.2 wt%), 13.61 MPa (0.5 wt%), and 6.25 MPa (1.0 wt%), respectively. Therefore, further improving the breakdown resistance and mechanical properties of the porous film is essential for the application of porous ultra-low dielectric polyimide materials.


1998 ◽  
Vol 524 ◽  
Author(s):  
Yanjun Ma ◽  
Hongning Yang ◽  
J. Guo ◽  
C. Sathe ◽  
A. Agui ◽  
...  

ABSTRACTPerformance of future generations of integrated circuits will be limited by the RC delay caused by on-chip interconnections. Overcoming this limitation requires the deployment of new high conductivity metals such as copper and low dielectric constant intermetal dielectrics (IMD). Fluorinated amorphous carbon (a-CFx) is a promising candidate for replacing SiO2 as the IMD. In this paper we investigated the structure and electronic properties of a-CFx thin films using high-resolution x-ray absorption, emission, and photoelectron spectroscopy. The composition and local bonding information were obtained and correlated with deposition conditions. The data suggest that the structure of the a-CFx is mostly of carbon rings and CF2 chains cross-linked with C atoms. The effects of growth temperature on the structure and the thermal stability of the film are discussed.


2005 ◽  
Vol 863 ◽  
Author(s):  
Alok Nandini ◽  
U. Roy ◽  
Zubin P. Patel ◽  
H. Bakhru

AbstractLow-κ dielectrics have to meet stringent requirements in material properties in order to be successfully integrated. A particularly difficult challenge for material development is to obtain a combination of low dielectric constant with good thermal and mechanical properties. Incorporation of low dielectric constant materials such as porous silica based materials as a replacement to conventional dielectrics like SiO2 and use of Cu metallization schemes has become a necessity as critical dimensions of devices decrease. This paper is focused on the challenges in developing materials with low dielectric constant but strong thermo mechanical properties. Thin films of Ultra-Low materials such as porous Methyl Silsesquioxane (MSQ) (κ=2.2) were implanted with argon 1 × 1016 cm-2 dose at energies varying from 20 to 50 keV at room temperature. This work shows that the surface hardness of the porous films can be improved five times as compared to the as-deposited porous films by implanting Ar with 1 × 1016 cm-2 doses at 20 keV, sacrificing only a slight increase (∼9%) in dielectric constant (e.g., from 2.2 to 2.4). The hardness persists after 4500C annealing. In this current work, an ion implantation strategy was pursued to create a SiO2-like surface on MSQ. The effects of implantation parameters on the barrier property and bulk stability of MSQ were then studied. The results reveal one possible route to attain the “zero barrier thickness” requirement for interconnects systems.


2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Dongliang Zhao ◽  
Yujun Zhang ◽  
Hongyu Gong ◽  
Baoxin Zhu ◽  
Xiaoyu Zhang

Si3N4wave-transparent composites with different volume content of BN nanoparticles (BNnp/Si3N4) were prepared by gas pressure sintering at 1800°C in N2atmosphere. The effects of BN nanoparticles on the dielectric and mechanical properties of BNnp/Si3N4composites were investigated. The results showed that the addition of the BN nanoparticles improved the dielectric properties of BNnp/Si3N4composites effectively and decreased the mechanical properties. When the volume content of BN nanoparticles was 10%, the dielectric constant and dielectric loss tangent were 4.31 and 0.006, respectively, and the bending strength and fracture toughness still reached 198.9 MPa and 3.36 MPa·m1/2. The high mechanical properties of BNnp/Si3N4composites with 10% BN nanoparticles were attributed to homogeneously dispersed BN nanoparticles which were embedded in the pores formed by the rod-likeβ-Si3N4.


Sign in / Sign up

Export Citation Format

Share Document