Abstract: A method is provided for making a composite substrate for electronic semiconductor parts. The composite substrate has a metal core, an insulating layer, and a conducting layer. The insulating layer is deposited by chemical vapor deposition in the gaseous phase on the metal core, or by chemical vapor deposition in combination with other techniques, such as plasmaspraying and/or melting. The metal core is comprised of a highly heat-resistant refractory metal, e.g., molybdenum, tungsten, titanium, molybdenum-manganese alloy, or a high-alloy steel having a permeability of about 1.002. The insulating layer is comprised of an inorganic material such as aluminum oxide or aluminum nitride. The conducting layer typically comprises copper.