Synergetic modulations in Ag2CaV4O12 via cation substitution and composite formation to optimize dielectric performances

Low-temperature co-fired ceramics technology (LTCC), as a remarkable integrated technology developed in recent years, has become the mainstream implementation of passive integration. Ceramic materials as the dielectric layers are required to have low sintering temperatures (<900 °C) to facilitate co-firing with conductive materials such as Ag and Cu. Herein, a series of low-firing dielectrics Ag 2- x Na x CaV 4 O 12 ( x = 0.1, 0.2, 0.3, and 0.4) were designed for potential application in LTCC. Such ceramics can be densified at extremely low temperatures (500–540 °C) with high relative densities (>95%), and possess promising dielectric properties ( ε r = 7.3 ∼ 7.5, Q × f = 48,500 ∼ 59,800 GHz, and τ f = −55.3 ∼ −29.4 ppm/°C). CaTiO 3 was added as a τ f compensator to tune the thermal drift of resonance frequency, yielding a near-zero τ f value combined with an ε r = 8.6 and Q × f = 47,100 GHz. Chemical compatibility with silver was also evaluated, rendering their application possible in LTCC.