A method of creating an electrical connection involves providing a pair of contacts (808,810) each on one of two different chips (802,804), the pair of contacts defining a volume therebetween, the volume containing at least two compositions each having melting points, the compositions having been selected such that heating to a first temperature will cause a change in at least one of the at least two compositions such that the change will result in a new composition having a new composition melting point of a second temperature, greater than the first temperature and the melting point of at least a first of the at least two compositions, and heating the pair of contacts and the at least two compositions to the first temperature. The method is useful in the manufacture of chip stacks where maintaining a solder hierarchy is important, the method allowing the same composition for joining chip contacts to be used at each chip-chip interface.