Structure and Composition Analysis of MBE Grown Ga2O3(Gd2O3) thin films on Si

• Main Authors: Mong-Chi Hang, 杭孟琦
• Other Authors: J. Raynien Kwo
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/83228497211157629990

碩士 === 國立清華大學 === 物理學系 === 94 === The current trend of Si CMOS scaling calls for replacing SiO2 with high k dielectrics in gate related applications. Excellent electrical properties and thermodynamic stability of the Ga2O3(Gd2O3)/GaAs hetero-structures are demonstrated in our previous work. Recently, we have extended our studies of employing high k materials Ga2O3(Gd2O3) to passivity Si surface by our in-situ molecular beam epitaxy (MBE) growth method. Composition of the as grown film was analyzed by X-ray photoelectron spectroscopy analysis. The X-ray photoelectron spectroscopy result implies the composition of the deposited films on Si substrate can be separated into three layers. These include a main Gd2O3 films, a gadolinium silicate interfacial layer at oxide/substrate interface, and a mixture of Ga2O3 and Gd2O3 layer on the surface. Studies using X-ray reflectivity measurement have shown the thickness of three layers and the roughness at their interfaces. Structural and morphological studies were carried out by high-resolution X-ray diffraction. High-quality nano-scale single-crystal Gd2O3 films have been grown epitaxially on Si (111) with a lattice mismatch of <1%. The structure of the Gd2O3 films is a cubic phase.