COMPOSITE SUBSTRATE, ELECTRONIC COMPONENT, AND METHOD OF MANUFACTURING COMPOSITE SUBSTRATE AND ELECTRONIC COMPONENT

A composite substrate having silicon substrate with excellent crystallinity and a method of manufacturing the composite substrate and an electronic component using the composite substrate are provided. A composite substrate (1) is configured to bond a support substrate (10) having electrical insulating property, and a silicon substrate (20) which is overlaid on the support substrate (10). The semiconductor substrate (20) of the composite substrate (1) includes a plurality of first regions (20x) in which a device function unit functioning as a semiconductor device is formed, and a second region (20y) located between these first regions (20x). In the semiconductor substrate (20) of the composite substrate (1), an amorphous form (22) containing silicon and a metal is present in the second region (20y).