High-temperature creep of low-dielectric-constant glass composites

1996 ◽  
Vol 11 (8) ◽  
pp. 2098-2103 ◽  
Author(s):  
Jau-Ho Jean

The constant-stress compressive creep behavior of a low-dielectric constant (low-k) glass composite, containing a low-softening-point borosilicate glass (BSG) and a high-softening-point high silica glass (HSG), has been investigated at 800–950 °C. For all stages of creep, the deformation behavior exhibits linear viscoelasticity, and is controlled by viscous flow of the low-softening-point borosilicate glass. An analytical expression is proposed to describe mathematically the creep behavior of the glass composite, and the results show a fairly good agreement with experimental observations.

1997 ◽  
Vol 12 (10) ◽  
pp. 2743-2750 ◽  
Author(s):  
Jau-Ho Jean ◽  
Chia-Ruey Chang

Camber (curvature) development during cofiring a two-layered structure of Ag film/low-dielectric-constant, low-temperature cofired ceramic (LTCC) green tape has been investigated. At a given thickness of Ag film, both the camber and camber rate decrease linearly with increasing the square thickness of LTCC. Densification mismatch between Ag and LTCC is attributed to be the root cause for the camber generation during cofiring. Mathematical analysis is made to theoretically describe the camber development, and the results show a fairly good agreement with experimental observations.


1999 ◽  
Vol 579 ◽  
Author(s):  
A. Demkov ◽  
R. Liu ◽  
S. Zollner ◽  
D. Werho ◽  
M. Kottke ◽  
...  

ABSTRACTFluorinated silica has a dielectric constant E in the range of 3—3.5, lower than that of F-free SiO2 (ω=4). The reasons behind this reduction are controversial. It is not known whether the electronic or ionic contributions to the overall screening are being diminished upon F doping. To shed more light on this phenomenon we have studied F-doped SiO2 with ab-initio modeling and various characterization techniques. FTIR transmission and spectroscopic ellipsometry give us information about the ionic and electronic contributions to ω Nuclear reaction analysis and Auger spectrometry measure F composition. XPS and FTIR provide information on the atomic structure and stability of the film. We use a large cell of cristobalite to model fluorinated silica theoretically. The ground state geometry is obtained via energy minimization. We calculate the vibrational density of states and find a localized mode (Si-F stretch), in good agreement with FTIR transmission. We analyze the effects of F incorporation on the dielectric properties.


1999 ◽  
Vol 565 ◽  
Author(s):  
Y. Shimogaki ◽  
S. W. Lim ◽  
E. G. Loh ◽  
Y. Nakano ◽  
K. Tada ◽  
...  

AbstractLow dielectric constant F-doped silicon oxide films (SiO:F) can be prepared by adding fluorine source, like as CF4 to the conventional PECVD processes. We could obtain SiO:F films with dielectric constant as low as 2.6 from the reaction mixture of SiH4/N2 O/CF4. The structural changes of the oxides were sensitively detected by Raman spectroscopy. The three-fold ring and network structure of the silicon oxides were selectively decreased by adding fluorine into the film. These structural changes contribute to the decrease ionic polarization of the film, but it was not the major factor for the low dielectric constant. The addition of fluorine was very effective to eliminate the Si-OH in the film and the disappearance of the Si-OH was the key factor to obtain low dielectric constant. A kinetic analysis of the process was also performed to investigate the reaction mechanism. We focused on the effect of gas flow rate, i.e. the residence time of the precursors in the reactor, on growth rate and step coverage of SiO:F films. It revealed that there exists two species to form SiO:F films. One is the reactive species which contributes to increase the growth rate and the other one is the less reactive species which contributes to have uniform step coverage. The same approach was made on the PECVD process to produce low-k C:F films from C2F4, and we found ionic species is the main precursor to form C:F films.


2020 ◽  
Author(s):  
Vedanki ◽  
Chandrabhan Dohare ◽  
Pawan KumarSrivastava ◽  
Premlata Yadav ◽  
Subhasis Ghosh

Sign in / Sign up

Export Citation Format

Share Document