An electronic integrated circuit chip includes a first transistor arranged inside and on top of a solid substrate, a second transistor arranged inside and on top of a layer of semiconductor material on insulator having a first thickness, and a third transistor arranged inside and on top of a layer of semiconductor material on insulator having a second thickness. The second thickness is greater than the first thickness. The solid substrate extends underneath the layers of semiconductor material and is insulated from those layers by the insulator.