Measurement and analysis of Si3N4 particles by infrared spectrum

In this paper, the principle of Attenuated Total Reflection (ATR) is used to test and study the silicon nitride particle samples, and the influence of particle size, shape and crystal phase on its infrared spectral performance is emphatically analyzed. It is found that the larger the particle size of Si₃N₄ is, the more its extinction peak moves to the long wave. The smaller the particle size is, the lower the extreme value of infrared transmission in the characteristic spectrum segment is. For Si₃N₄ particles of the same scale, spherical like particles can obtain lower infrared transmittance, while cylindrical like ones show a wider range of infrared absorption bands. Under the same shape and similar scale, α phase Si₃N₄ particles have better infrared absorption than β phase.