A bump bonding process and product are disclosed in which both pressure and heating are used in situations where the temperature should not exceed a predetermined amount, e.g., bonding of a photoconductor array to a module containing electronic processing devices. The bonding process involves eutectic alloying of indium and bismuth, thus allowing welding of the bumps at a temperature substantially below the two metals' melting points. In one version of the invention, bumps (24, 28) on adjacent substrates (20, 26) are directly aligned. In another version, each bump (74) on one substrate (70) is wedged between a pair of bumps (78a, 78b) on the other substrate (76).