scholarly journals Influence of Interfacial Delamination on Channel Cracking of Brittle Thin Films

2007 ◽  
Vol 990 ◽  
Author(s):  
Yaoyu Pang ◽  
Rui Huang

ABSTRACTChanneling cracks in low-k dielectrics have been observed to be a key reliability issue for advanced interconnects. The constraint effect of surrounding materials including stacked buffer layers has been studied. This paper analyzes the effect of interfacial delamination on the fracture condition of brittle thin films on elastic substrates. It is found that stable delamination along with the growth of a channel crack is possible only for a specific range of elastic mismatch and interface toughness. An effective energy release rate is defined to account for the influence of interfacial delamination on both the driving force and the fracture resistance, which can be significantly higher than the case assuming no delamination.

Author(s):  
Jason R. Heffelfinger ◽  
C. Barry Carter

Yttria-stabilized zirconia (YSZ) is currently used in a variety of applications including oxygen sensors, fuel cells, coatings for semiconductor lasers, and buffer layers for high-temperature superconducting films. Thin films of YSZ have been grown by metal-organic chemical vapor deposition, electrochemical vapor deposition, pulse-laser deposition (PLD), electron-beam evaporation, and sputtering. In this investigation, PLD was used to grow thin films of YSZ on (100) MgO substrates. This system proves to be an interesting example of relationships between interfaces and extrinsic dislocations in thin films of YSZ.In this experiment, a freshly cleaved (100) MgO substrate surface was prepared for deposition by cleaving a lmm-thick slice from a single-crystal MgO cube. The YSZ target material which contained 10mol% yttria was prepared from powders and sintered to 85% of theoretical density. The laser system used for the depositions was a Lambda Physik 210i excimer laser operating with KrF (λ=248nm, 1Hz repetition rate, average energy per pulse of 100mJ).


1997 ◽  
Vol 473 ◽  
Author(s):  
Michael Lane ◽  
Robert Ware ◽  
Steven Voss ◽  
Qing Ma ◽  
Harry Fujimoto ◽  
...  

ABSTRACTProgressive (or time dependent) debonding of interfaces poses serious problems in interconnect structures involving multilayer thin films stacks. The existence of such subcriticai debonding associated with environmentally assisted crack-growth processes is examined for a TiN/SiO2 interface commonly encountered in interconnect structures. The rate of debond extension is found to be sensitive to the mechanical driving force as well as the interface morphology, chemistry, and yielding of adjacent ductile layers. In order to investigate the effect of interconnect structure, particularly the effect of an adjacent ductile Al-Cu layer, on subcriticai debonding along the TiN/SiO2 interface, a set of samples was prepared with Al-Cu layer thicknesses varying from 0.2–4.0 μm. All other processing conditions remained the same over the entire sample run. Results showed that for a given crack growth velocity, the debond driving force scaled with Al-Cu layer thickness. Normalizing the data by the critical adhesion energy allowed a universal subcriticai debond rate curve to be derived.


2018 ◽  
Author(s):  
K. A. Rubin ◽  
W. Jolley ◽  
Y. Yang

Abstract Scanning Microwave Impedance Microscopy (sMIM) can be used to characterize dielectric thin films and to quantitatively discern film thickness differences. FEM modeling of the sMIM response provides understanding of how to connect the measured sMIM signals to the underlying properties of the dielectric film and its substrate. Modeling shows that sMIM can be used to characterize a range of dielectric film thicknesses spanning both low-k and medium-k dielectric constants. A model system consisting of SiO2 thin films of various thickness on silicon substrates is used to illustrate the technique experimentally.


2014 ◽  
Vol 881-883 ◽  
pp. 1117-1121 ◽  
Author(s):  
Xiang Min Zhao

ZnO thin films with different thickness (the sputtering time of AlN buffer layers was 0 min, 30 min,60 min, and 90 min, respectively) were prepared on Si substrates using radio frequency (RF) magnetron sputtering system.X-ray diffraction (XRD), atomic force microscope (AFM), Hall measurements setup (Hall) were used to analyze the structure, morphology and electrical properties of ZnO films.The results show that growth are still preferred (002) orientation of ZnO thin films with different sputtering time of AlN buffer layer,and for the better growth of ZnO films, the optimal sputtering time is 60 min.


2013 ◽  
Vol 9 (6) ◽  
pp. 723-728 ◽  
Author(s):  
Bhavana N. Joshi ◽  
A. M. Mahajan
Keyword(s):  

2006 ◽  
Vol 914 ◽  
Author(s):  
George Andrew Antonelli ◽  
Tran M. Phung ◽  
Clay D. Mortensen ◽  
David Johnson ◽  
Michael D. Goodner ◽  
...  

AbstractThe electrical and mechanical properties of low-k dielectric materials have received a great deal of attention in recent years; however, measurements of thermal properties such as the coefficient of thermal expansion remain minimal. This absence of data is due in part to the limited number of experimental techniques capable of measuring this parameter. Even when data does exist, it has generally not been collected on samples of a thickness relevant to current and future integrated processes. We present a procedure for using x-ray reflectivity to measure the coefficient of thermal expansion of sub-micron dielectric thin films. In particular, we elucidate the thin film mechanics required to extract this parameter for a supported film as opposed to a free-standing film. Results of measurements for a series of plasma-enhanced chemical vapor deposited and spin-on low-k dielectric thin films will be provided and compared.


MRS Advances ◽  
2016 ◽  
Vol 1 (37) ◽  
pp. 2635-2640 ◽  
Author(s):  
Adele Moatti ◽  
Reza Bayati ◽  
Srinivasa Rao Singamaneni ◽  
Jagdish Narayan

ABSTRACTBi-epitaxial VO2 thin films with [011] out-of-plane orientation were integrated with Si(100) substrates through TiO2/TiN buffer layers. At the first step, TiN is grown epitaxially on Si(100), where a cube-on-cube epitaxy is achieved. Then, TiN was oxidized in-situ ending up having epitaxial r-TiO2. Finally, VO2 was deposited on top of TiO2. The alignment across the interfaces was stablished as VO2(011)║TiO2(110)║TiN(100)║Si(100) and VO2(110) /VO2(010)║TiO2(011)║TiN(112)║Si(112). The inter-planar spacing of VO2(010) and TiO2(011) equal to 2.26 and 2.50 Å, respectively. This results in a 9.78% tensile misfit strain in VO2(010) lattice which relaxes through 9/10 alteration domains with a frequency factor of 0.5, according to the domain matching epitaxy paradigm. Also, the inter-planar spacing of VO2(011) and TiO2(011) equals to 3.19 and 2.50 Å, respectively. This results in a 27.6% compressive misfit strain in VO2(011) lattice which relaxes through 3/4 alteration domains with a frequency factor of 0.57. We studied semiconductor to metal transition characteristics of VO2/TiO2/TiN/Si heterostructures and established a correlation between intrinsic defects and magnetic properties.


1992 ◽  
Vol 275 ◽  
Author(s):  
G. Cui ◽  
C. P. Beetz ◽  
B. A. Lincoln ◽  
P. S. Kirlin

ABSTRACTThe deposition of in-situ YBa2CU3O7-δ Superconducting films on polycrystalline diamond thin films has been demonstrated for the first time. Three different composite buffer layer systems have been explored for this purpose: (1) Diamond/Zr/YSZ/YBCO, (2) Diamond/Si3N4/YSZ/YBCO, and (3) Diamond/SiO2/YSZ/YBCO. The Zr was deposited by dc sputtering on the diamond films at 450 to 820 °C. The YSZ was deposited by reactive on-axis rf sputtering at 680 to 750 °C. The Si3N4 and SiO2 were also deposited by on-axis rf sputtering at 400 to 700 °C. YBCO films were grown on the buffer layers by off-axis rf sputtering at substrate temperatures between 690 °C and 750 °C. In all cases, the as-deposited YBCO films were superconducting above 77 K. This demonstration enables the fabrication of low heat capacity, fast response time bolometric IR detectors and paves the way for the use of HTSC on diamond for interconnect layers in multichip modules.


2013 ◽  
Vol 364 ◽  
pp. 30-33 ◽  
Author(s):  
Norihiro Suzuki ◽  
Kentaro Kaneko ◽  
Shizuo Fujita

2002 ◽  
Vol 17 (7) ◽  
pp. 1863-1870 ◽  
Author(s):  
Richard P. Vinci ◽  
Stefanie A. Forrest ◽  
John C. Bravman

Wafer curvature was used to study the thermal–mechanical behavior of 1-μm Cu thin films capped with a 100-nm-thick Si3N4 layer. These films were grown with either a Ta or a Si3N4 underlayer. Films on Si3N4 that were exposed to oxygen at the film/capping layer interface or at the center of the copper layer exhibited Bauschinger-like yielding at low stress. Stacks deposited under continuous vacuum, with a Ta underlayer, with carbon exposure at the upper surface of the copper film, or with oxygen exposure of only the underlayer did not demonstrate the anomalous yielding. Preferential diffusion of oxygen into copper grain boundaries or interfaces is the likely cause of the early yield behavior. Possible mechanisms include an increase in interface adhesion due to the presence of oxygen in solution and diffusion-induced dislocation glide as an additional driving force for dislocation motion at low applied stress.


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