Development of low-temperature sintering nano-Ag pastes using lowering modulus technologies

This paper will discuss the fundamental study on nano-silver pastes newly developed with a unique approach using MO (Metallo-organic) technology. MO technology provides a low-temperature sintering capability. The nano-silver pastes show high electrical and thermal performance. However, degradation of die shear strength has been found by thermal cycling test due to the fragility of porous sintered structure. To improve the mechanical property, resin reinforcing technology has been developed. By adding special resin to the pastes, the porous area is filled with the resin and the sintered structure is reinforced. Additionally, lowering modulus technology has been developed. By adding thermoplastic resin particles to the pastes, the reliability can be improved because the resin reduces the stress caused by the CTE mismatch between the die and substrate.