Interfacial structures between aluminum nitride and Cu–P–Sn–Ni brazing alloy with Ti film

Abstract

Control of Ag electro chemical migration is crucial for long-term reliability of electrical components in high-voltage applications. In this work, Cu was bonded onto an AlN substrate at temperatures between 650 °C and 950 °C for 1 h using a Ag Free Cu-P-Sn-Ni brazing filler metal with Ti as an active metal addition. The interfacial structure between the Cu and the AlN and the mechanical properties of the bond were both investigated. Three different phases which contain Ti and O were observed during the growth process of the Cu/AlN interfacial reaction layer: an amorphous P-Ti-O phase, an amorphous Ti-O phase and rutile, TiO2. The most stable Cu/AlN interfacial structure occurred when rutile was present, and where a particular orientation relationship with AlN was observed: TiO2 (101)//AlN (0001), TiO2[010]//AlN [1120 ]. The probability of Cu/AlN interfacial fracture decreased as the bonding temperature was increased. Cu/AlN interfacial fracture was completely suppressed above 850 °C where rutile was the dominant phase at the Cu/AlN interface.

Enhanced shear strength of Cu/AlN/Cu gradient materials with continuous and quasi‐continuous interfacial structures

“…2 Liao et al 3 used a W-Cu composite with a lower coefficient of thermal expansion (CTE) instead of pure Cu to form the joint with AlN, which can prevent mechanical failures at the interface resulting from mismatched CTE between Cu and AlN. The maximum average tensile strength for the joints reached 26.76 MPa at 800 • C. Terasaki et al 4 utilized a kind of Ag-free Cu-P-Sn-Ni brazing alloy with Ti as an active metal addition to joining Cu and AlN. They found that Cu/AlN interfacial fracture was completely suppressed above 850 • C, where rutile was the dominant phase at the Cu/AlN interface.…”

“…The maximum average tensile strength for the joints reached 26.76 MPa at 800°C. Terasaki et al 4 . utilized a kind of Ag‐free Cu–P–Sn–Ni brazing alloy with Ti as an active metal addition to joining Cu and AlN.…”

Development of a Novel Low-Silver Cu-P Brazing Filler Metal Bearing Sn

“…In addition, the melting temperature of Cu-P brazing filler metal is still too high to braze copper alloys with low melting points, such as brass. Therefore, several novel Cu-P brazing filler metals have been developed, such as Cu-P-Ni [5,6], Cu-P-Ag [7], Cu-P-Sn [8,9], Cu-P-Zr [10] and Cu-P-RE (rare earth) [11], some of which have been used in the manufacturing industry for brazing copper alloys.…”