A stationary target anode (10) of an X-ray device is provided, having stepped high Z button (20). By minimizing the diameter (27) of the central, X-ray producing section of the button (20), and incorporating a thin lip (40) extending therefrom to a diameter approximately twice that of the central portion, internal and interface stresses are minimized. A flexible structure is also provided to support the button/substrate assembly and provide minimal resistance as the substrate radially expands during heating, thereby minimizing induced stress on the target and preventing fatigue and failure of the support target.