Substrate for alternative semiconductor die configurations

A method of assembling semiconductor devices with semiconductor dies of alternative configurations, the method comprising:

• providing a substrate panel having an array of internal electrical contact elements on a first face for connection to the semiconductor dies, fiducial markings on the first face for guiding apparatus performing operations on the first face of the substrate panel, and an array of external electrical contact elements on a second face, opposite the first face, for connection to external electrical circuitry, wherein the internal and external electrical contact elements are aligned and electrically connected through the substrate panel by respective vias;
• placing and mounting an array of semiconductor dies of a selected configuration on the first face of the substrate panel using the fiducial markings, each of the semiconductor dies having bonding pads;
• electrically connecting the internal electrical contact elements of the substrate panel with the bonding pads of the semiconductor dies;
• and
• singulating the substrate panel with the semiconductor dies using the fiducial markings;
• wherein the fiducial markings include main fiducial markings located proximate to an outer perimeter of the substrate panel and at corners thereof, and an array of subsidiary fiducial markings corresponding to arrays of semiconductor dies of the different alternative configurations, wherein the array of subsidiary fiducial markings extends in two orthogonal dimensions and has a pitch that is a sub-multiple of a pitch of the arrays of semiconductor dies of different alternative configurations, and wherein the internal electrical contact elements are disposed in orthogonal rows, and adjacent rows thereof have a spacing equal to the pitch of the subsidiary fiducial markings.