A method of bonding a first substrate to a second substrate includes disposing a first high melting point metal layer onto a first substrate, disposing a first low melting point metal layer onto the first high melting point metal layer, disposing a second high melting point metal layer onto a second substrate, and disposing a second low melting point metal layer onto the second high melting point metal layer. The method further includes applying precursor metal particles onto the first and/or second low melting point metal layers, positioning the first and second low melting point metal layers such that the precursor metal particles contact both the first and second low melting point metal layers, and bonding the first substrate to the second substrate by heating the precursor metal particles and each metal layer to form an intermetallic alloy bonding layer between the first and second substrates.

A solder paste includes a flux and powder mixed with the flux, where the powder includes first powder and second powder mixed with each other. The first powder may be a tin (Sn) and at least one metal dissolved in the tin (Sn), and the second powder may be a copper (Cu) powder, the surface of which is coated with silver (Ag).

A preform structure for soldering a semiconductor chip arrangement includes a carbon fiber composite sheet and a solder layer formed over the carbon fiber composite sheet.

A preform structure for soldering a semiconductor chip arrangement includes a carbon fiber composite sheet and a solder layer formed over the carbon fiber composite sheet.