GROWTH OF EPITAXIAL PRO2 THIN-FILMS ON HYDROGEN TERMINATED SI (111) BY PULSED LASER DEPOSITION

A new epitaxial oxide, PrO2, has been grown on Si (111) by pulsed laser deposition. X-ray diffraction shows that films are oriented with the PrO2[111] direction parallel to the substrate [111]. The full width at half maximum for the omega rocking curve on the PrO2 (222) peak is as low as 0.75°, while phi scans indicate in-plane epitaxial alignment to better than one degree. In the best quality films, epitaxy is almost pure type-b epitaxy which is characteristic of epitaxial CaF2 on Si. To achieve epitaxy, it is essential to remove the native silicon oxide from the substrate prior to film growth. This is done at room temperature using a wet-chemical hydrogen-termination procedure.