Ground ring for metal electronic package

The component for an electronic package (10) has a metallic substrate (12) with a surface (16) coated by a dielectric (32). A centrally disposed cavity (22) extends through the dielectric (32) into the metallic substrate (12) to a depth, D1. Circumscribing and abutting this cavity (22) is an annular channel (30) having a depth D2 that is less than D1. A semiconductor device (12) bonded to the base (24) of the cavity (22) is electrically interconnected (46) to both circuit traces (34) formed on the dielectric coating (32) and to the annular channel (30). A method of forming the annular channel (30) is to mechanically mill a precursor annular channel (58) having an outer wall (60) a desired distance from the sidewalls (20) of the metallic substrate (12) and a width substantially greater than the desired width of the annular channel (30). A cavity (22) is then formed in the region circumscribed by the outer wall (60) of the precursor annular channel (58).