Enhanced Sinterability, Thermal Conductivity and Dielectric Constant of Glass-Ceramics with PVA and BN Additions

Abstract

With the rapid development of the microelectronics industry, many efforts have been made to improve glass-ceramics’ sinterability, thermal conductivity, and dielectric properties, which are essential components of electronic materials. In this study, low-alkali borosilicate glass-ceramics with PVA addition and glass-BN composites were prepared and successfully sintered at 770 °C. The phase composition, density, microstructure, thermal conductivity, and dielectric constant were investigated. It was shown that PVA addition contributes to the densification process of glass-ceramics (~88% relative density, with closed/open pores in the microstructure) and improves the thermal conductivity of glass material from 1.489 to 2.453 W/K.m. On the other hand, increasing BN addition improves microstructures by decreasing porosities and thus increasing relative densities. A glass-12 wt. % BN composite sample exhibited almost full densification after sintering and presented apparent and open pores of 2.6 and 0.08%, respectively. A high thermal conductivity value of 3.955 W/K.m and a low dielectric constant of 3.00 (at 5 MHz) were observed in this material. Overall, the resulting glass-ceramic samples showed dielectric constants in the range of 2.40–4.43, providing a potential candidate for various electronic applications.

Effect of Al2O3 and ZrO2 Filler Material on the Microstructural, Thermal and Dielectric Properties of Borosilicate Glass-Ceramics

“…Furthermore, glass-ceramics’ excellent heat conductivity and their composites contribute to this result since no Al 2 O 3 or ZrO 2 degradation was detected due to the sintering temperature and preparation techniques used. According to the previous literature, AlN, Si 3 N 4 , SiC, and BN have also been used instead of Al 2 O 3 and ZrO 2 [ 15 , 21 , 23 , 34 ]. However, glass-ceramics with ZrO 2 additives show a more effective way to contribute to composites than Al 2 O 3 by comparing their thermal conductivity values with different glass-ceramic content [ 35 ].…”

“…Several glass-ceramic systems have been developed for LTCC applications. Among several glass applications, including LTCCs, using boron oxides such as boron trioxide in glass/alumina composites is a new method that has been mentioned previously [ 21 , 22 ]. B 2 O 3 addition to the B 2 O 3 —Al 2 O 3 —SiO 2 glass-ceramic systems provides increased bending strength.…”

“…The densification and properties of glass-ceramics were improved with the addition of 4 wt.% Al 2 O 3 . Adding fillers is an effective method to synthesize solid materials with higher thermal conductivity [ 21 , 23 ]. The addition of BN and PVA to a low-alkali borosilicate glass-ceramic was investigated for its effect of sinterability, thermal conductivity and dielectric constant in a previous study [ 21 ].…”

“…Adding fillers is an effective method to synthesize solid materials with higher thermal conductivity [ 21 , 23 ]. The addition of BN and PVA to a low-alkali borosilicate glass-ceramic was investigated for its effect of sinterability, thermal conductivity and dielectric constant in a previous study [ 21 ]. The thermal conductivity and dielectric constants increased with 12 wt.% BN addition with a nearly fully dense structure.…”

“…The combination of Al 2 O 3 and SiO 2 improves the mechanical and chemical properties; however, at higher temperatures, the mechanical and chemical properties deteriorate [ 27 ]. B 2 O 3 was utilized in the formulation to avoid this issue [ 21 , 28 ]. Apart from the conventional melt-quenching method, a new powder metallurgical route was used to prepare the glass powder.…”