Effect of cooling rate after hot pressing on electrical conductivity of Si3N4-ceramics with TiO2 and TiH2 additives

Abstract

It has been established that cooling rate after hot pressing has influence on microstructure, electrical conductivity and charge storage in Si3N4 ceramics with TiO2 and TiH2 additives, which can be used as substrates for the large capacity microassemblies by Flip-Chip technology. It was shown that the critical cooling rate is 30°C/min for the Si3N4-TiO2and 50°C/min for the Si3N4-TiH2 ceramics. Electrical conductivity is structurally sensitive property, strongly connected with evolution of Si3N4 microstructure. The best properties are typical for Si3N4 ceramics characterized by mono-trap state level with the activation energy of about 0.8 eV, obtained at the characteristic cooling rates.

Keywords

• Sialon
• Titanium oxide
• Titanium hydride
• Hot pressing
• Cooling rate
• d.c. conductivity