A substrate (1) is formed from a non-electrically conducting material and is for mounting a semiconductor chip (10). The substrate has a semiconductor chip mounting portion (6). A number of first electrically conducting contact portions (5) are formed on the surface of the material and associated with the mounting portion (6). A second electrically conducting contact portion (3) is formed on the surface of the material, and the second electrically conducting contact portion (3) is adapted to be coupled to testing equipment. A number of electrically conducting paths (4) are formed on the surface of the material. The conducting paths (4) electrically connect the second electrically conducting contact portion (3) to a minority of the first electrically conducting contact portions (5).