Review of Low Dielectric Constant Thick Film Electronic Ceramics Using Hollow Microspheres

1994 ◽  
Vol 372 ◽  
Author(s):  
David W. Kellerman

AbstractHigh speed interconnects for semiconductor devices require low dielectric constant materials to minimize propagation delays and capacitive line loading. Ceramics and thick film materials have been utilized to package these semiconductor devices, however their dielectric constants are prohibitively high. Hollow microspheres have been added to thick film glass and ceramic composite materials to lower the dielectric constant of those materials. This paper will review papers presented on the work done at Digital Equipment Corporation and EMCA-Remex to develop high speed integrated circuit packages with low dielectric constants.Presented will be the development and characterization of the low dielectric constant thick film material, processes used to fabricate devices with the low dielectric constant material, and development of the application of the material to an advanced ceramic integrated circuit package.

2011 ◽  
Vol 2011 (1) ◽  
pp. 000544-000552
Author(s):  
Deepukumar M. Nair ◽  
James Parisi ◽  
K.M. Nair ◽  
Mark McCombs ◽  
Michael Smith ◽  
...  

Low Temperature Co-fired Ceramic (LTCC) material systems have been successfully used in microwave and millimeter wave systems for several years. LTCC has very low dielectric loss, high reliability due to inherent hermeticity; high interconnect density, multilayer processing capability leading to true 3D packaging, and better cost-performance balance. While the medium range dielectric constants (7.00 – 8.00) offered by current tape systems have advantages, it is generally difficult to realize high speed systems and efficient antennas on LTCC, especially at millimeter wave frequencies. The difficulty arises from the reduced signal propagation velocity in high-speed applications, and lower radiation efficiency for antennas, both due to higher dielectric constant. To enable and extend applications of LTCC technology to these subsystems, DuPont has developed a new low dielectric constant LTCC system – DuPont™ GreenTape™ 9K5 - which has a dielectric constant of 5.80 (at 10 GHz) that is compatible with the commercial DuPont™ GreenTape™ 9K7 LTCC System. This is achieved without compromising excellent microwave loss properties of the 9KX GreenTape™ platform. These materials systems enable high-speed, high reliability applications while also realizing efficient antennas on LTCC. This paper presents initial characterization of the new DuPont™ GreenTape™ 9K5 LTCC system consisting of low K dielectric tape, gold and silver conductors to evaluate the effects of chemistry, processing conditions, processing latitude, microstructure, and microwave performance. Test coupons with various transmission and resonating structures are designed, fabricated, and tested for the evaluation of transmission losses and dielectric properties. Stability of the material system over multiple re-fire steps is also examined


MRS Bulletin ◽  
1997 ◽  
Vol 22 (10) ◽  
pp. 33-38 ◽  
Author(s):  
Nigel P. Hacker

Low-dielectric-constant materials (k < 3.0) have the advantage of facilitating manufacture of higher performance integrated-circuit (IC) devices with minimal increases in chip size. The reduced capacitance given by these materials permits shrinkage of spacing between metal lines to below 0.25 μm and the ability to decrease the number of levels of metal in a device. The technologies being considered for low-k applications are chemical vapor deposition (CVD) or spin-on of polymeric materials. For both types of processes, there are methods and materials capable of giving k < 3.0 dielectric stacks. This article will focus on the spin-on approach and discuss the properties of both organic and inorganic spin-on polymers.While CVD SiO2 has been the mainstay of the industry, spin-on materials are appropriate for many dielectric applications. Polyimides have applications as electrical insulators, and traditional spin-on silicates or siloxanes (k > 3.0) have served as planarizing dielectrics during the last 15 years. The newer spin-on polymers have greatly enhanced mechanical, thermal, and chemical properties, exhibiting lower dielectric constants than the traditional materials.


2018 ◽  
Vol 31 (8) ◽  
pp. 986-995
Author(s):  
Lei Wang ◽  
Guifen Gong ◽  
Junyao Shen ◽  
Jinsong Leng

Polyimide (PI)/titanium dioxide (TiO2) composite nanofibers (NFs) with average diameters of 200–250 nm were synthesized via electrospinning. The total number density of dipoles decreased significantly, owing to the porous structures and compact interface between TiO2 NPs and PI matrix. All PI/TiO2 NFs maintain low dielectric constants and losses. For example, the dielectric constants of PI/TiO2-6% NFs are all lower than 2.6, being exposed to temperatures from 25°C to 200°C. Meantime, the dielectric losses of PI/TiO2-6% NFs are below 0.005. For ultraviolet (UV)-light shielding performance, the PI/TiO2 NFs exhibited good UV-light shielding and corresponding anti-photoaging properties. The reason can be ascribed from high UV-light absorption and scattering ability in the TiO2 NPs. The best UV-light absorption (average: 3.71) and corresponding absorption decay (15.13%) were achieved for optimized PI/TiO2-6% NFs. Other fundamental characteristics, such as the thermal stability, mechanical tensile property, and hydrophobicity, were also investigated. Such low dielectric constant PI/TiO2 composite NFs can be alternatively chosen under a longtime UV-light exposing condition.


1986 ◽  
Vol 72 ◽  
Author(s):  
G. V. Chandrashekhar ◽  
M. W. Shafer

AbstractDielectric properties have been measured for a series of porous and fully densified silica glasses, prepared by the sol-gel technique starting from Si-methoxide or Si-fume. The results for the partially densified glasses do not show any preferred orientation for porosity. When fully densified (˜2.25 gms/cc) without any prior treatment of the gels, they have dielectric constants of ≥ 6.5 and loss factors of 0.002 at 1 MHz, compared to values of 3.8 and <0.001 for commercial fused silica. There is no corresponding anomaly in the d.c. resistivity. Elemental carbon present to the extent of 400–500 ppm is likely to be the main cause for this enhanced dielectric constant. Extensive cleaning of the gels prior to densification to remove this carbon were not completely successful pointing to the difficulty in preparing high purity, low dielectric constant glasses via the organic sol-gel route at least in the bulk form.


1999 ◽  
Vol 565 ◽  
Author(s):  
T. Aoki ◽  
Y Shimizu ◽  
T. Kikkawa

AbstractA novel spin on material derived from perhydropolysilazane that converts into ultra-low k inorganic films is described in this paper. The obtained films, cured at 400°C in N2 atmosphere, exhibit dielectric constants as low as 1.6 which do not change after holding the wafers in a clean-room mbient for 2 months. Cross-sectional SEM images of the cured films show the aggregation of small granules with diameters ranging from 5 to 30 nm. The films can be obtained by conventional SOG process: spin-coating, baking and curing, without any additional process such as hydrophobic treatment.The average atomic compositions of the films are, Si/O/N/C = 40/55/5/0.5 (atomic %), by XPS analysis. These results indicate that the films have hydrogen silicon oxynitride structures. No evolution of H2O and NH3 was detected by TDS analysis in the temperature range of RT to 800°C. Hydrophobic Si-H and Si-H2 groups remaining in the film might prevent water absorption, resulting in the low dielectric constant.The remainder of Si-H and Si-H2 constituents in the cured films is the result of selective oxidation reactions of perhydropolysilazane in the baking process with the use of a specific catalyst. The structures of the films are tailored by altering the amount of the catalyst. In this study, we also demonstrate the relationship between the effect of the catalyst and the film properties.


1970 ◽  
Vol 23 (5) ◽  
pp. 905 ◽  
Author(s):  
PJ Pearce ◽  
W Strauss

The electrolytic conductance of solutions of potassium chloride and tetrabutyl- ammonium picrate over a range of concentrations have been measured in dioxan-water mixtures containing 0, 25, 50, 70, and 80% dioxan at 25� and pressures up to 1000 and 2500 bars respectively for the two solutes. The solvent concentration range corresponds to a range of dielectric constants of 78.3 (for water) to 11.98 (80% dioxan). The association of KCl in solutions of low dielectric constant is reduced by increasing pressure, so that the conductances of the solutions of finite concentration are not reduced as much by pressure as at infinite dilution. In contrast to this, the solutions of the tetrabutylammonium picrate are wholly dissociated even in very low dielectric constant solvents, as is shown by the limited concentration dependence of the conductance pressure characteristics.


2012 ◽  
Vol 262 ◽  
pp. 448-453 ◽  
Author(s):  
Jian Yong Lv ◽  
Yan Meng ◽  
Li Fan He ◽  
Teng Qiu ◽  
Xiao Yu Li ◽  
...  

A novel fluorine containing epoxy 4-fluoro-4′,4″-diepoxypropoxy triphenyl methane (FDE) was designed and synthesized. The synthesized epoxy was cured by methyl nadic anhydride (MNA) and diglycidyl ether of bisphenol A (DGEBA) was chosen for comparison. Both glass transfer temperature (Tg) and 5% weight loss degradation temperature (Td5%) of cured FDE are over 60°C higher than that of DGEBA. Dielectric constants of the cured FDE at 106 Hz and 107 Hz are 3.09 and 2.91, comparing to 3.50 and 3.24 of the cured DGEBA, respectively. Furthermore, water absorption of the cured FDE is lower than that of DGBEA.


2001 ◽  
Vol 390 (1-2) ◽  
pp. 113-118 ◽  
Author(s):  
Chang Shil Yang ◽  
Kyoung Suk Oh ◽  
Jai Yon Ryu ◽  
Doo Chul Kim ◽  
Jing Shou-Yong ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document